{"id":25328,"date":"2020-12-23T05:08:22","date_gmt":"2020-12-23T05:08:22","guid":{"rendered":"https:\/\/samacheer-kalvi.com\/?p=25328"},"modified":"2021-12-06T15:56:24","modified_gmt":"2021-12-06T10:26:24","slug":"samacheer-kalvi-12th-bio-botany-guide-chapter-9","status":"publish","type":"post","link":"https:\/\/samacheer-kalvi.com\/samacheer-kalvi-12th-bio-botany-guide-chapter-9\/","title":{"rendered":"Samacheer Kalvi 12th Bio Botany Guide Chapter 9 Plant Breeding"},"content":{"rendered":"

Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Bio Botany Guide<\/a> Pdf Chapter 9 Plant Breeding Text Book Back Questions and Answers, Notes.<\/p>\n

Tamilnadu Samacheer Kalvi 12th Bio Botany Solutions Chapter 9 Plant Breeding<\/h2>\n

12th Bio Botany Guide Plant Breeding Text Book Back Questions and Answers<\/h3>\n

I. Choose the correct answer<\/span><\/p>\n

Question 1.
\nAssertion : Genetic variation provides the raw material for selection.
\nReason : Genetic variations are differences in genotypes of the individuals.
\na) Assertion is right and reason is wrong.
\nb) Assertion is wrong and reason is right.
\nc) Both reason and assertion is right.
\nd) Both reason and assertion is wrong.
\nAnswer:
\nb) Assertion is wrong and reason is right.<\/p>\n

Question 2.
\nWhile studying the history of domestication of various cultivated plants ………………. were recognized earlier.
\na) Centres of origin
\nb) Centres of domestication
\nc) Centres of hybrid
\nd) Centres of variation
\nAnswer:
\na) Centres of origin<\/p>\n

\"<\/p>\n

Question 3.
\nPick out the odd pair …………..
\na) Mass selection – Morphological characters
\nb) Purline selection – Repeated self pollination
\nc) Clonal selection \u2014 Sexually propagated
\nd) Natural selection – Involves nature
\nAnswer:
\nc) Clonal selection – Sexually propagated<\/p>\n

Question 4.
\nMatch Column I with Column II
\n\"Samacheer
\nAnswer:
\nb) i -III, ii-I, iii-IV, iv-II<\/p>\n

Question 5.
\nThe quickest method of plant breeding is
\na) Introduction
\nb) Selection
\nc) Hybridization
\nd) Mutation breeding
\nAnswer:
\nb) Selection<\/p>\n

\"<\/p>\n

Question 6.
\nDesired improved variety of economically useful crops are raised by
\na) Natural selection
\nb) hybridization
\nc) mutation
\nd) biofertilisers
\nAnswer:
\nb) hybridization<\/p>\n

Question 7.
\nPlants having similar genotypes produced by plant breeding are called
\na) clone
\nb) haploid
\nc) autopolyploid
\nd) genome
\nAnswer:
\na) clone<\/p>\n

Question 8.
\nImporting better varieties and plants from outside and acclimatising them to local environment is called
\na) cloning
\nb) heterosis
\nc) selection
\nd) introduction
\nAnswer:
\nd) Introduction<\/p>\n

\"<\/p>\n

Question 9.
\nDwarfing gene of wheat is
\na) pal 1
\nb) Atomita 1
\nc) Norin 10
\nd) pelita 2
\nAnswer:
\nc) Norin 10<\/p>\n

Question 10.
\nCrosses between the plants of the same variety are called
\na) interspecific
\nb) inter varietal
\nc) intra varietal
\nd) inter generic
\nAnswer:
\nc) Intra varietal<\/p>\n

Question 11.
\nProgeny obtained as a result of repeat self pollination a cross pollinated crop to called
\na) pure line
\nb) pedigree line
\nc) inbreed line
\nd) heterosis
\nAnswer:
\nb) Pure line<\/p>\n

\"<\/p>\n

Question 12.
\nJaya and Ratna are the semi dwarf varieties of
\na) wheat
\nb) rice
\nc) cowpea
\nd) mustard
\nAnswer:
\nb) Rice<\/p>\n

Question 13.
\nWhich one of the following are the species that are crossed to give sugarcane varieties with high sugar, high yield, thick stems and ability to grow in the sugarcane belt of North India?
\na) Saccharum robustum and Saccharum officinarum
\nb) Saccharum barberi and Saccharum officinarum
\nc) Saccharum sinense and Saccharum officinarum
\nd) Saccharum barberi and Saccharum robustum
\nAnswer:
\nb)Saccharum barberi and Saccharum officinarum<\/p>\n

Question 14.
\nMatch column I (crop) with column II (Corresponding disease resistant variety) and select the correct option from the given codes.
\n\"Samacheer
\nAnswer:
\nb) I-(ii), II-(i), IH-(iii), IV-(iv)<\/p>\n

\"<\/p>\n

Question 15.
\nA Wheat variety, Atlas 66 which has been used as a donor for improving cultivated wheat, which is rich in
\na) iron
\nb) carbohydrates
\nc) proteins
\nd) vitamins
\nAnswer:
\nc) proteins<\/p>\n

Question 16.
\nWhich one of the following crop varieties correct matches with its resistance to a disease<\/p>\n\n\n\n\n\n\n\n
Variety<\/td>\nResistance to disease<\/td>\n<\/tr>\n
a. Pusa Komal<\/td>\nBacterial blight<\/td>\n<\/tr>\n
b. Pusa Sadabahar<\/td>\nWhite rust<\/td>\n<\/tr>\n
c. Pusa Shubhra<\/td>\nChilli mosaic virus<\/td>\n<\/tr>\n
d. Brassica<\/td>\nPusa swarnim<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Answer:
\na) Pusa Komal – Bacterial blight<\/p>\n

Question 17.
\nWhich of the following is incorrectly paired?
\na) Wheat – Himgiri
\nb) Milch breed – Sahiwal
\nc) Rice – Ratna
\nd) Pusa Komal – Brassica
\nAnswer:
\nd) Pusa Komal – Brassica<\/p>\n

\"<\/p>\n

Question 18.
\nMatch list I with list II<\/p>\n\n\n\n\n\n\n\n\n
List I<\/td>\nList II<\/td>\n<\/tr>\n
Biofertilizer<\/td>\nOrganisms<\/td>\n<\/tr>\n
i. Free living N2<\/td>\na. Aspergillus<\/td>\n<\/tr>\n
ii. Symbiotic N2<\/td>\nb. Arnanita<\/td>\n<\/tr>\n
iii. P Solubilizing<\/td>\nc. Anabaena azollae<\/td>\n<\/tr>\n
iv. P Mobilizingd.<\/td>\nd. Azotobactor<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

a. i c, ii a, iii b, iv d
\nb. i d, ii c, iii a, iv b
\nc. i a, ii c, iii b, iv d,
\nd. i b, ii a, iii d, iv c
\nAnswer:
\nb. i d, ii c, iii a, iv b<\/p>\n

Question 19.
\nDifferentiate primary introduction from secondary introduction
\nAnswer:<\/p>\n\n\n\n\n\n
Primary introduction<\/td>\nSecondary introduction<\/td>\n<\/tr>\n
1. The introduced Variety is well adapted to the new environment.
\n2. There is no alternation to the original genotype<\/td>\n		1. The introduced Variety is subjected to selection
\n2. The introduced Variety is subjected to selection
\n3. That variety is hybridized with a local variety to transfer one or a few characters to them.<\/td>\n<\/tr>\n
\n

–<\/p>\n<\/td>\n

Example :
\nTea varieties collected from china and North East India initially grown in Botanical garden of kolkate from which appropriate clones have selected and introduced to different parts of India.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Question 20.
\nHow are microbial innoculants used to increase the soil fertility?
\nAnswer:<\/p>\n

Biofertilizers or microbial innoculants are defined as preparations containing living cells or latent cells of efficient strains of microorganisms that help crop plants uptake of nutrients by their interactions in the rhizosphere when applied through seed or soil.<\/p>\n

They are efficient in fixing nitrogen, solubilising phosphate and decomposing cellulose. They are designed to improve the soil fertility, plant growth, and also the number and biological activity of beneficial microorganisms in the soil. They are ecofriendly organic agro inputs and are more efficient and cost effective than chemical fertilizers.<\/p>\n

\"<\/p>\n

Question 21.
\nWhat are the different types of hybridization?
\nAnswer:
\nTypes of hybridization:<\/p>\n

(i) Intravarietal hybridization:
\nThe cross between the plants of same variety. such crosses are useful only in the self. pollinated crops.<\/p>\n

(ii) Intervarietal hybridization:
\nThe cross between the plants belonging to two different varieties of the same species and is also known as intraspecific hybridization.<\/p>\n

(iii) Interspecific hybridization:
\nThe cross between the plants belonging to different species belonging to the same genus is also called intragenic hybridization.
\nExample:
\nGossypium hirsutum
\nGossypium arboreum<\/p>\n

(v) Intergeneric hybridization:<\/p>\n

    \n
  • The crosses are made between the plants belonging to two different genera.<\/li>\n
  • The disadvantages are hybrid sterility time consuming and expensive procedure.
    \nExample : Raphanobrassica x Triticale<\/li>\n<\/ul>\n

    Question 22.
    \nExplain the best suited type followed by plant breeders at present?
    \nAnswer:
    \nMutation breeding represents a new method of conventional breeding procedures as they have the advantage of improving the defect without losing an agronomic and quality character in agriculture and crop improvement. Mutation means the sudden heritable changes in the genotype or phenotype of an organism. Gene mutations are of considerable importance in plant breeding as they provide essential inputs for evolution as well as for recombination and selection. It is the only method for improving seedless crops.<\/p>\n

    \"<\/p>\n

    Question 23.
    \nWrite a note on heterosis.
    \nAnswer:<\/p>\n

      \n
    • The superiority of the FI hybrid in performance over its parents is called heterosis or hybird vigour.<\/li>\n
    • G.H. Shull was the first scientist to use the term heterosis in 1912.<\/li>\n
    • Heterosis are of the following types.<\/li>\n
    • Euheterosis, Mutational Euheterosis, Balanced Euheterosis and Pseudoheterosis<\/li>\n<\/ul>\n

      (i) Euheterosis:
      \nThis is the true heterrosis which is inherited and is further classified as.<\/p>\n

      (a) Mutational Euheteosis:
      \nSimplest type of euheterosis and results from the sheltering or eliminating of the deleterious unfavourable often lethal, recessive, mutant genes by their adaptively superior dominant alleles in cross pollinated crops.<\/p>\n

      (b) Balanced Euheterosis :
      \nwell balanced gene combinations which is more adaptive to environmental conditions and agricultural usefulness.<\/p>\n

      (ii) Psuedohetrosis:
      \nAlso termed as luxuriance progeny possess superiority over parents in vegetative growth but not in yield and adaptation usually sterile or poorly fertile.<\/p>\n

      Question 24.
      \nList out the new breeding techniques involved in developing new traits in plant breeding.
      \nAnswer:
      \nNew Breeding Techniques (NBT) are a collection of methods that could increase and accelerate the development of new traits in plant breeding. These techniques often involve genome editing, to modify DNA at specific locations within the plants to produce new traits in crop plants. The various methods of achieving these changes in traits include the following.<\/p>\n

        \n
      • Cutting and modifying the genome during the repair process by tools like CRISPR \/Cas.<\/li>\n
      • Genome editing to introduce changes in a few base pairs using a technique called Oligonucleotide-directed mutagenesis (ODM).<\/li>\n
      • Transferring a gene from an identical or closely related species (cisgenesis).<\/li>\n
      • Organizing processes that alter gene activity without altering the DNA itself (epigenetic methods)<\/li>\n<\/ul>\n

        \"<\/p>\n

        12th Bio Botany Guide Plant Breeding Additional Important Questions and Answers<\/h3>\n

        I. Match the Following<\/span><\/p>\n

        Question 1.<\/p>\n\n\n\n\n\n\n\n
        Column A<\/td>\nColumn B<\/td>\n<\/tr>\n
        a. Darwins’s evolutionary theory<\/td>\nI. Origin of Cultivated plants<\/td>\n<\/tr>\n
        b. Vavilov<\/td>\nII. 12 mega gene centres<\/td>\n<\/tr>\n
        c. Zhukovsky<\/td>\nIII. 12 main geographic centres<\/td>\n<\/tr>\n
        d. De candolle<\/td>\nIV. Natural selection and Hybridization<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        A) a – iv, b – iii, c – ii, d – i
        \nB) a – iv, b – ii, c – iii, d – i
        \nC) a – ii, b – i, c – iv, d – iii
        \nD) a – i, b – iv, c – ii, d – iii
        \nAnswer:
        \nA) a – iv, b – iii, c – ii, d – i<\/p>\n

        Question 2.<\/p>\n\n\n\n\n\n\n\n
        Column A<\/td>\nColumn B<\/td>\n<\/tr>\n
        a. Green Revolution<\/td>\nI. Muller and stadler<\/td>\n<\/tr>\n
        b. Mutation Breeding<\/td>\nII. G.H. Shull<\/td>\n<\/tr>\n
        c. Heterosis<\/td>\nIII. William S. Gaud<\/td>\n<\/tr>\n
        d. Director of IARI<\/td>\nIV. Dr.B.P. Pal<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        A) a – ii, b – iii, c-iv, d-i
        \nB) a – iii, b-ii, c-i, d-iv
        \nc) a – iii, b – i, c-ii, d-iv
        \nD) a – i, b-iv c-iii, d-ii
        \nAnswer:
        \nc) a – iii, b – i, c – i, d – iv<\/p>\n

        \"<\/p>\n

        Question 3.<\/p>\n\n\n\n\n\n\n\n
        Column A<\/td>\nColumn B<\/td>\n<\/tr>\n
        a. Mesoamerica<\/td>\nI. Sesame<\/td>\n<\/tr>\n
        b. South East Asia<\/td>\nII. Bamboo<\/td>\n<\/tr>\n
        c. Abyssinian<\/td>\nIII. Guava<\/td>\n<\/tr>\n
        d. China<\/td>\nIV. Hemp<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        A) a – ii, b – iii, c- i, d – iv
        \nB) a – i, b – ii, c – iv, d – iii
        \nc) a – iv, b – i, c – ii, d – iii
        \nD) a – iii, b – iv c – i, d – iv
        \nAnswer:
        \nD) a – iii, b – iv c – i, d – iv<\/p>\n

        Question 4.<\/p>\n\n\n\n\n\n\n\n
        Column A<\/td>\nColumn B<\/td>\n<\/tr>\n
        a. Atomic Garden<\/td>\nI. Dwarfing Genes<\/td>\n<\/tr>\n
        b. Protein Enriched<\/td>\nII. Caesium 137<\/td>\n<\/tr>\n
        c. Vitamin C Entiched<\/td>\nIII. French Peas<\/td>\n<\/tr>\n
        d. Norin 10<\/td>\nIV. Bitter Gourd<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        A) a – i, b – ii, c – iv, d – iii
        \nB) a – ii, b – iii, c – iv, d – i
        \nc) a – iii, b – iv, c – i, d – iii
        \nD) a – iv, b – i, c – iii, d – ii
        \nAnswer:
        \nB) a – ii, b – iii, c – iv, d – i<\/p>\n

        \"<\/p>\n

        II. Choose the Odd man Out<\/span><\/p>\n

        Question 1.
        \na) Rhizoblum
        \nb) Azolla
        \nc) Trichoderma
        \nd) Arbuscular mycorhizae
        \nAnswer:
        \nc) Trichoderma<\/p>\n

        Question 2.
        \na) Anabaena
        \nb) Amanita
        \nc) Nostoc
        \nd) Azospirillum
        \nAnswer:
        \nb) Amanita<\/p>\n

        Question 3.
        \na) Natural selection
        \nb) Mass selection
        \nc) Purelinc selection
        \nd) Clonal selection
        \nAnswer:
        \na) Natural selection<\/p>\n

        Question 4.
        \na) Cesium
        \nb) Nitromethyl
        \nc) Urea
        \nd) X-ray
        \nAnswer:
        \nd) X-ray<\/p>\n

        \"<\/p>\n

        III. Choose the incorrect Pair<\/span><\/p>\n

        Question 1.<\/p>\n\n\n\n\n\n\n\n
        Column A<\/td>\nColumn B<\/td>\n<\/tr>\n
        a. China<\/td>\n1. Bamboo<\/td>\n<\/tr>\n
        b. South East Asia<\/td>\n2. Coconut<\/td>\n<\/tr>\n
        c. Ethiopia<\/td>\n3. Castor<\/td>\n<\/tr>\n
        d. South America<\/td>\n4. Onion<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        Answer:
        \nd) South America – Onion<\/p>\n

        Question 2.<\/p>\n\n\n\n\n\n\n\n
        Column A<\/td>\nColumn B<\/td>\n<\/tr>\n
        a. C.T.Patel<\/td>\n1. First Cotton hybrid<\/td>\n<\/tr>\n
        b. Dr. B.P. Pal<\/td>\n2. Superior disease resistant wheat<\/td>\n<\/tr>\n
        c. Dr. K. Ramiah<\/td>\n3. Wheat breeder<\/td>\n<\/tr>\n
        d. Sir. T.S. Venkataraman<\/td>\n4. Sugar cane breeder<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        Answer:
        \nC) Dr. K. Ramiah – Wheat breeder<\/p>\n

        \"<\/p>\n

        Question 3.<\/p>\n\n\n\n\n\n\n\n
        Column A<\/td>\nColumn B<\/td>\n<\/tr>\n
        a. N2 Fixing Bacteria<\/td>\n1. Bacillus<\/td>\n<\/tr>\n
        b. Fungi<\/td>\n2. Penicillium<\/td>\n<\/tr>\n
        c. Bacillus<\/td>\n3. Silicate and Zinc Solubilizers<\/td>\n<\/tr>\n
        d. Symbiotic<\/td>\n4. Rhizobium<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        Answer:
        \na) N2 Fixing Bacteria – Bacillus<\/p>\n

        Question 4.<\/p>\n\n\n\n\n\n\n\n
        Column A<\/td>\nColumn B<\/td>\n<\/tr>\n
        a. Free Living fungi<\/td>\n1. Trichoderma<\/td>\n<\/tr>\n
        b.Entomopathogenic<\/td>\n2. Beauveria<\/td>\n<\/tr>\n
        c. Green Manuring<\/td>\n3. Sonora – 63<\/td>\n<\/tr>\n
        d. Green Leaf Manure<\/td>\n4. Cassia fistula<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        Answer:
        \nc) Green Manuring – Sonora – 63<\/p>\n

        \"<\/p>\n

        IV. Choose the incorrect Pair<\/span><\/p>\n

        Question 5.<\/p>\n\n\n\n\n\n\n\n
        Column A<\/td>\nColumn B<\/td>\n<\/tr>\n
        a. Domestication wheat<\/td>\n1. 1926<\/td>\n<\/tr>\n
        b. Blast resistant Rice<\/td>\n2. 1940<\/td>\n<\/tr>\n
        c. Insect Resistant Cotton<\/td>\n3. 1903<\/td>\n<\/tr>\n
        d. Waxy Corn<\/td>\n4. 1953<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        Answer:
        \nb) Blast resistant Rice -1940<\/p>\n

        Question 6.<\/p>\n\n\n\n\n\n\n\n
        Column A<\/td>\nColumn B<\/td>\n<\/tr>\n
        a. Green Manuring<\/td>\n1. Tephrosia purpurea<\/td>\n<\/tr>\n
        b. Rhizoctonia Solani<\/td>\n2. Potato<\/td>\n<\/tr>\n
        c. Rice Variety<\/td>\n3. Sonora 64<\/td>\n<\/tr>\n
        d. Ectomycorrhiza<\/td>\n4. Nostoc<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        Answer:
        \na) Green Manuring – Tephrosia purpurea<\/p>\n

        \"<\/p>\n

        Question 7<\/p>\n\n\n\n\n\n\n\n
        Column A<\/td>\nColumn B<\/td>\n<\/tr>\n
        a. Mutational Breeding<\/td>\n1. Triticale<\/td>\n<\/tr>\n
        b. Polyploid Breeding<\/td>\n2. Atomita -2<\/td>\n<\/tr>\n
        c. M.S. Swaminathan<\/td>\n3. TN 1 – hybrid rice<\/td>\n<\/tr>\n
        d. Jaya and Ratna<\/td>\n4. Semi dwarf wheat<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        Answer:
        \nc) M.S. Swaminathan – TN 1 – hybrid rice<\/p>\n

        Question 8.<\/p>\n\n\n\n\n\n\n\n
        Column A<\/td>\nColumn B<\/td>\n<\/tr>\n
        a. Wheat<\/td>\n1. Pusa komal<\/td>\n<\/tr>\n
        b. Cow pea<\/td>\n2. pusa sadabahar<\/td>\n<\/tr>\n
        c. Brassica<\/td>\n3. Himgiri<\/td>\n<\/tr>\n
        d. Cauliflower<\/td>\n4. Pusa shubhra<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        Answer:
        \nd) Cauliflower – Pusa shubhra<\/p>\n

        \"<\/p>\n

        V. Assertion and Reason<\/span><\/p>\n

        Question 1.
        \nAssertion : Growing of green manure crops and use of these crops as manure is called Green Manuring.
        \nReason : It helps to increase the nitrogen in the soil.
        \na) A & R are true.
        \nb) A & R are Wrong.
        \nc) A is true and R is Wrong.
        \nd) A is wrong and R is true.
        \nAnswer:
        \na) A & R are true.<\/p>\n

        Question 2.
        \nAssertion : Dr. M.S. Swaminathan is called “Father of green revolution in India.
        \nReason : He strived hard for conservation of traditional rice varities.
        \na) Both A & R is True.
        \nb) Both A & R is Wrong.
        \nc) A is True and R is Wrong.
        \nd) A is wrong and R is True.
        \nAnswer:
        \nc) A is True and R is Wrong<\/p>\n

        \"<\/p>\n

        Question 3.
        \nAssertion(A): A variety formed by pure line selection method shows more homozggosity with respect to all genes.
        \nReason(R): The pure line plants are produced by asexual method of vegetative propagation method.
        \na) (A) is correct; (R) is wrong
        \nb) (A) is wrong; (R) is correct
        \nc) (A) is correct; (R) does not explain
        \nd) (A) is correct; (R) explain (A)
        \nAnswer:
        \na) (A) is correct; (R) is wrong<\/p>\n

        Question 4.
        \nAssertion : Earliest record of Agriculture is found in the fertile Crescent region in and around River Nile
        \nReason : Approximately 12000, years ago Fertile crescent region is in and around. Tigris and Euphrates river.
        \na) Both A & R are True.
        \nb) Both A & R are Wrong.
        \nc) A is True and R is Wrong.
        \nd) A is Wrong and R is True.
        \nAnswer:
        \nd) A is Wrong and R is True<\/p>\n

        \"<\/p>\n

        VI. Choose the Correct Statements<\/span><\/p>\n

        Question 1.
        \na) Vavilov Studied 247 Cultivated plants
        \nb) Zhukovsky divided the whole world into 12 mega gene centres.
        \nc) Valvilo intially propose 12 main geographic centres of origin
        \nd) Harlan put forward the concept of mega gene centre for the origin of cultivated plants
        \nAnswer:
        \nb) Zhukovsky divided the whole world into 12 mega gene centres<\/p>\n

        Question 2.
        \na) Foxtail mullet was domesticated by India
        \nb) Wheat & Pea war domesticated by Ethiopia.
        \nc) Castor and Coffee was domesticated by central East
        \nd) Tomato & Pineapple was domesticated by south America
        \nAnswer:
        \nd) Tomato & Pineapple was domesticated by south America<\/p>\n

        \"<\/p>\n

        Question 3.
        \na) Seaweeds has more than 70 minerals vitamins and enzymes
        \nb) Trichoderma is a parasitic fungi.
        \nc) Rhizobium is a pathogenic bacteria
        \nd) Azolla is submerged water fern
        \nAnswer:
        \na) Seaweeds has more than 70 minerals vitamins and enzymes<\/p>\n

        Question 4.
        \na) Hirngiri is a wheat variety that is resistant to Bacterial blight disease.
        \nb) A Variety of CowPea, Pusakomal is resistent to Hill bunt disease.
        \nc) Pusa shubra is a cauliflower variety that is resistant to Black rot disease
        \nd) Pusa swarnim is a variety of Brassica that is resistent to TMV disease
        \nAnswer:
        \nc) Pusa shubra is a cauliflower variety that is resistant to Black disease<\/p>\n

        \"<\/p>\n

        VII. Choose the incorrect Statements<\/span><\/p>\n

        Question 1.
        \na) Mr. Jayaraman was a disciple of Dr. Nammalvar
        \nb) Normal E. Borlaug was awarded Noble prize for peace in 1970.
        \nc) M.S. Swaminathan produced the first semidwarf fertiliser responsive hybrid variety of rice TN 1..
        \nd) Green revolution the term was Coined by Muller
        \nAnswer:
        \nd) Green revolution the term was Coined by Muller<\/p>\n

        Question 2.
        \nThe disadvantage of pureline selection is
        \na) It is difficult to distinguish between hereditary variation from environmental variation.
        \nb) New genotypes are never created so they are less stable to environmental fluctuations
        \nc) The genotype is unchanged for a long period of time.
        \nd) The plants show more heterozygosity.
        \nAnswer:
        \nc) The genotype is unchanged for a long period of time.<\/p>\n

        Question 3.
        \nThe possible changes in the plant species due to domestication are
        \na) Adaptation to a greater diversity of environments.
        \nb) Uniform flowering and fruiting.
        \nc) Drop in Yield
        \nd) Change in breeding system
        \nAnswer:
        \nc) Drop in yield<\/p>\n

        \"<\/p>\n

        Question 4.
        \na) Rhizobiurn is best suited for the wheat fields.
        \nb) Azolla that fixes the atmospheric nitrogen along with blue green algae.
        \nc) Arbuscular mycorrhizae also assures water availability
        \ncl) Sea weed liquid fertilizer improves resistance of plants to frost and disease.
        \nAnswer:
        \na) Rhizobium is best suited for the wheat fields<\/p>\n

        VIII. Choose the correct answer.<\/span><\/p>\n

        Question 1.
        \nThe domesticated crop of Mesoamerica is …………………..
        \na) Tomato
        \nb) Pine apple
        \nc) Sweet Potato
        \nd) Rubber
        \nAnswer:
        \na) Tomato<\/p>\n

        Question 2.
        \nThe domesticated plant of the chiloe centre.
        \na) Maize
        \nb)Potato
        \nc) Tobacco
        \nd) Olive
        \nAnswer:
        \na) Maize<\/p>\n

        \"<\/p>\n

        Question 3.
        \nThe domesticated plant of the Near East is______
        \na) Rye
        \nb) Rice
        \nc) hemp
        \nd) Cotton
        \nAnswer:
        \na) Rye<\/p>\n

        Question 4.
        \nName the rice variety with saline tolerance and pest resistance.
        \na) Wild-type rice
        \nb) Atomita – 2
        \nc) Dwarf rice variety
        \nd) Golden rice
        \nAnswer:
        \nb) Atomita -2<\/p>\n

        Question 5.
        \nBiofertilizers could be also called as …………………
        \na) Viral inoculants
        \nb) Myco inoculants
        \nc) Protozoan inoculants
        \nd) Bacterial Inoculants
        \nAnswer:
        \nd) Bacterial Inoculants<\/p>\n

        \"<\/p>\n

        Question 6.
        \nBeauveria species act as a parasite on …………… species.
        \na) Mammals
        \nb) Aves
        \nc) Arthropod
        \nd) Amphibians
        \nAnswer:
        \nc) Arthropod<\/p>\n

        Question 7.
        \nDamping off of ……………. is caused by Rhizoctonia solani.
        \na) Tomato
        \nb) Potato
        \nc) Millet
        \nd) Maize
        \nAnswer:
        \na) Tomato<\/p>\n

        Question 8.
        \nPongamia pinnata is an important plant species useful for ………………. manure.
        \na) Organic
        \nb) Potassium rich
        \nc) Green leaf
        \nd) Calcium rich
        \nAnswer:
        \nc) Green leaf<\/p>\n

        \"<\/p>\n

        Question 9.
        \nMatch the following and find the correct answer
        \n(i) Rhizobium – (A) Water ferm
        \n(ii) Trichoderma – (B) Green manuring
        \n(iii) Azolla – (C) Symbiotic bacterium
        \n(iv) Crotolaria – (D) Free living fungus
        \na) (i) B; (ii) C; (iii) D; (iv) A
        \nb) (i) C; (ii) D; (iii) B; (iv) A
        \nc) (i) C; (ii) D; (iii) A; (iv) B
        \nd) (i) B; (ii) D; (iii) C; (iv) A
        \nAnswer:
        \nc) (i) C; (ii) D; (iii) A; (iv) B<\/p>\n

        Question 10.
        \nMore Vigorous hybrid corn was developed in _______
        \na) 1926
        \nb) 1943
        \nc) 1950
        \nd) 1936
        \nAnswer:
        \na) 1926<\/p>\n

        Question 11.
        \nIn 10,000 BC Domestication of ……………….. was done.
        \na) Maize
        \nb) Paddy
        \nc) Wheat
        \nd) Sugar cane
        \nAnswer:
        \nc) Wheat<\/p>\n

        \"<\/p>\n

        Question 12.
        \nThe newly introduced plant was carefully examined by the process called …………….
        \na) PCR Method
        \nb) Dots Method
        \nc) Cisgenesid
        \nd) Quarantine
        \nAnswer:
        \nd) Quarantine<\/p>\n

        Question 13.
        \nNational Bureau of plant Genetic Resources is located at ……………….
        \na) Rangpuri
        \nb) Andhra
        \nc) Pune
        \nd) Bihar
        \nAnswer:
        \na) Rangpuri<\/p>\n

        Question 14.
        \nHereditary Variation cannot be distinguished from environmental variation in ………………
        \na) Pureline selection
        \nb) Clonal Selection
        \nc) Mass Selection
        \nd) Hybridization
        \nAnswer:
        \nc) Mass Selection<\/p>\n

        \"<\/p>\n

        Question 15.
        \nJohannsen in 1903 coined the word.
        \na) Clonal Selection
        \nb) Pure line
        \nc) Mass Selection
        \nd) Heterosis
        \nAnswer:
        \nb) Pure line<\/p>\n

        Question 16.
        \nWhich one of the following is a biopesticide?
        \na) Azolla
        \nb) Rhizobium
        \nc) Beauveria
        \nd) Hevea
        \nAnswer:
        \nc) Beauveria<\/p>\n

        \"<\/p>\n

        Question 17.
        \n…………….. is the best suited measure for maintaining hybrid vigour.
        \na) Asexual reproduction
        \nb) Vegetative Propagation
        \nc) Grafting
        \nd) Cutting
        \nAnswer:
        \nb) Vegetative Propagation<\/p>\n

        Question 18.
        \n…………. is also termed as luxuriance.
        \na) Euheterosis
        \nb) Heterosis
        \nc) Mutational heterosis
        \nd) Pseudo heterosis
        \nAnswer:
        \nd) Pseudo heterosis<\/p>\n

        Question 19.
        \nMuller and Stadler coined the term ………………….
        \na) Mutation Breeding
        \nb) Modern Breeding
        \nc) Plant Breeding
        \nd) Poly ploidy
        \nAnswer:
        \na) Mutation Breeding<\/p>\n

        \"<\/p>\n

        Question 20.
        \nMutation Breeding is the only method of improving …………… crops.
        \na) Multi seeded
        \nb) single seeded
        \nC) seedless
        \nd) Nutritional
        \nAnswer:
        \nc) seedless<\/p>\n

        Question 21.
        \nBose Research institute at Calcutta is the first …………. in India.
        \na) Botanical garden
        \nb) planatorium
        \nc) Zoological park
        \nd) Gamma garden
        \nAnswer:
        \nd) Gamma garden<\/p>\n

        Question 22.
        \nWhich one of the following selection method takes longer time in bringing about desired variation?
        \na) clonal selection
        \nb) Mass selection
        \nc) pureline selection
        \nd) Natural selection
        \nAnswer:
        \nd) Natural selection<\/p>\n

        \"<\/p>\n

        Question 23.
        \n(A) was originally grown in North India
        \n(B) was orginally grown in South India
        \na) (A) Saccharum officinarum (B) Saccharum bareri
        \nb) (A) Saccharu bareri (B) Saccharum officinarum
        \nc) (A) Saccharum coarctatum (B) Saccharum alopecuroidum
        \nd) (A) Saccharum alopecuroidum (B) Saccharu coarctatum
        \nAnswer:
        \nb) (A) Saccharu bareri (B) Saccharum officinarum<\/p>\n

        Question 24.
        \nGreen revolution is the ………………. Agricultural revolution.
        \na) Third
        \nb) second
        \nc) third
        \nd) fourth
        \nAnswer:
        \na) Third<\/p>\n

        Question 25.
        \n…………….. received the national award for best genome saviour. .
        \na) Nel jeyaraman
        \nb) C.T.Patel
        \nc) Dr.B.P.Pal
        \nd) N.G.P.Rao
        \nAnswer:
        \na) Nel jeyaraman<\/p>\n

        \"<\/p>\n

        Question 26.
        \n……………. is the breeding of crops for improved nutritional quality
        \na) Plant Breeding
        \nb) Heterosis
        \nc) Mutation
        \nd) Biofortification
        \nAnswer:
        \nd) Biofortification<\/p>\n

        Question 27.
        \nHigh aspartic acid maize leads to resistance to ………………….
        \na) aphids
        \nb) jassids
        \nc) maize stem borer
        \nd) leaf roller
        \nAnswer:
        \nc) maize stem borer<\/p>\n

        Question 28.
        \nWhich one of the following is not a free living N2 fixing organism?
        \na) Anabaena azollae
        \nb)Azotobacter
        \nc) Clostridium
        \nd) Nostoc
        \nAnswer:
        \nc) Clostridium<\/p>\n

        \"<\/p>\n

        IX. Fill in the blanks.<\/span><\/p>\n

        1. De candolle in his ……………. studied 247 caltivated plants.
        \nAnswer:
        \nOrigen of cultivated plants<\/p>\n

        2. Bamboo eas demesticated by ……………….
        \nAnswer:
        \nChina<\/p>\n

        3. He was an eminet Sorghum breeder,devoloped World’s first hybrid of Sorghum CSH-1.
        \nAnswer:
        \nN.G.P.Rao.<\/p>\n

        \"<\/p>\n

        4. ……………… is used as a biofertilizer for wetland rice cultivation
        \nAnswer:
        \nAzolla.<\/p>\n

        5. Vavilov in the year ………………. converted 8 main geographic centres of origin to 12
        \nAnswer:
        \n1935<\/p>\n

        6. Harlan says that the centre of crop plants means the places of ……………… origin of the crop plants.
        \nAnswer:
        \nAgricultural<\/p>\n

        7. The ……………… was domesticate only in the Chiloe centre
        \nAnswer:
        \nPotato<\/p>\n

        \"<\/p>\n

        8. ………………. could be also called as Bioinoculants
        \nAnswer:
        \nBiofertilizers<\/p>\n

        9. C.T.Patel devoloped World’s first …………….. hybrid
        \nAnswer:
        \nCotton<\/p>\n

        10. Choudhary ram dhan made …………….. as punjab granary of India.
        \nAnswer:
        \nWheat<\/p>\n

        11. Azdla is used as biofertiliser for wetland rice cultivation and is known to contribute …………….\/ha\/crop.
        \nAnswer:
        \n40-60 kg<\/p>\n

        \"<\/p>\n

        12. …………….. is Associated with Phycomycetous fungi and angiosperm roots.
        \nAnswer:
        \nArbuscular Mycorhizzoe<\/p>\n

        13. ……………… contains Auxin,Cytokinin and Gibberellins
        \nAnswer:
        \nSeaweed liquid fertiliser<\/p>\n

        14. ……………… species are free living fungi that are common in soil and root ecosystem
        \nAnswer:
        \nTrichoderma<\/p>\n

        15. Damping of tomato is caused by ……………..
        \nAnswer:
        \nRhizoctonia Solani<\/p>\n

        \"<\/p>\n

        16. It is one of the most important green manure crops
        \nAnswer:
        \nTephrosia Purpurea<\/p>\n

        17. The double helix structure of DNA was identified by ……………. and …………….
        \nAnswer:
        \nJames Watson,Francis Crick<\/p>\n

        18. By 2050 we will …………….. need more food to feed the rapid growing population.
        \nAnswer:
        \n50%<\/p>\n

        19. Crop domestication started early during ……………….
        \nAnswer:
        \n10,000 Bc<\/p>\n

        20. ………………. Corn was developed using targetted breeding.
        \nAnswer:
        \nWaxy<\/p>\n

        \"<\/p>\n

        21. Rice variety of ……………. introduced from Philippines
        \nAnswer:
        \nIR8<\/p>\n

        22. NBPGR is located in Chennai at …………………..
        \nAnswer:
        \nMeenembakkan<\/p>\n

        23. Introduced plants get adapted to the new environment is called as ……………….
        \nAnswer:
        \nAcclimatization<\/p>\n

        24. Tea varieties collected from China and North East India initially grown in Botanical garden of ……………….
        \nAnswer:
        \nKolkatta
        \nSelection<\/p>\n

        \"<\/p>\n

        25. ______ is the oldest and basic method of plant breeding
        \nAnswer:
        \nPreliminary<\/p>\n

        26. In clonal selection …………… yield trial takes place during 3rd year.
        \nAnswer:
        \nIntrageneric<\/p>\n

        27. Interspecific hybridization is also called as _____
        \nAnswer:
        \nhybridization<\/p>\n

        28. Green revolution scheme began in ……………. in 1940’s.
        \nAnswer:
        \nMexico<\/p>\n

        \"<\/p>\n

        29. In 2005 …………….. organized a first ever traditional paddy seed festival in his farm as an individual.
        \nAnswer:
        \nNel jayaraman<\/p>\n

        30. …………… is a cleaving protein.
        \nAnswer:
        \nCas9<\/p>\n

        X. Two Marks<\/span><\/p>\n

        Question 1.
        \nWhat is Economic Botany?
        \nAnswer:
        \nIt is the study of the relationship between people and economically important plants.<\/p>\n

        Question 2.
        \nWhen did people started practising Agriculture?
        \nAnswer:<\/p>\n

          \n
        • Archeological evidence for earliest record of agriculture is found in the fertile crescent region in and around Tigris and Euphrates river valleys, approximate about 12,000 years
          \nago<\/li>\n<\/ul>\n

          Question 3.
          \nWhat was the contribution by De Candolle towards agriculture?
          \nAnswer:<\/p>\n

            \n
          • He studied 247 cultivated plant species.<\/li>\n
          • He attempted to solve the mystery about the anscestral form, region of domestication and history.<\/li>\n<\/ul>\n

            \"<\/p>\n

            Question 4.
            \nHow many geographic centres were proposed by vavilov?
            \nAnswer:<\/p>\n

              \n
            • Initially he proposed eight main geographic centres of origin.<\/li>\n
            • Later by dividing few centres into two or three centres and added a new centre USA.<\/li>\n
            • Thus making the 8 centres of Origin into 12.<\/li>\n<\/ul>\n

              Question 5.
              \nDefine Biofertilizers.
              \nAnswer:<\/p>\n

                \n
              • It is defined as preparations containing living cells of efficient strains of micro organisms that help in crop yield.<\/li>\n<\/ul>\n

                Question 6.
                \nWhat is component of seaweed liquid fertilizer?
                \nAnswer:<\/p>\n

                  \n
                • It contains Cytokinin, Gibberellins, and auxin a part from macro & micro nutrients.<\/li>\n
                • It has Alginates, Carbohydrate, 70 types of minerals, Vitaming and enzymes.<\/li>\n<\/ul>\n

                  \"<\/p>\n

                  Question 7.
                  \nTrichoderma has been recognised as bio\u00accontrol agent – Give Reasons.
                  \nAnswer:<\/p>\n

                    \n
                  • It control plant diseases<\/li>\n
                  • Ability to enhance root growth.<\/li>\n
                  • Increases crop productivity.<\/li>\n
                  • Provides resistance to abiotic stress.<\/li>\n
                  • Helps in uptake and use of nutrients.<\/li>\n<\/ul>\n

                    Question 8.
                    \nWhat is plant introduction?
                    \nAnswer:<\/p>\n

                      \n
                    • Introduction of genotypes from a place where it is normally grown to a new place.<\/li>\n
                    • eg. IR & Rice from Philippines.<\/li>\n<\/ul>\n

                      Question 9.
                      \nDefine Acclimatization?
                      \nAnswer:<\/p>\n

                        \n
                      • The adjustment or adaptation of the introduced plant in the changed environment is called acclimatization.<\/li>\n<\/ul>\n

                        \"<\/p>\n

                        Question 10.
                        \nWhat is Quarantine?
                        \nAnswer:<\/p>\n

                          \n
                        • All the introduced Crop must be free from presence of weeds, insects and disease causing Organisms.<\/li>\n
                        • It has to be carefully examined by the process called quarantine.<\/li>\n
                        • A strict isolation imposed to prevent the spread of disease.<\/li>\n<\/ul>\n

                          Question 11.
                          \nWhat is Natural Selection?
                          \nAnswer:<\/p>\n

                            \n
                          • This is a rule in the nature.<\/li>\n
                          • It results in evolution reflected in the Darwinian’s principle survival of the fittest.<\/li>\n
                          • It takes longer time to bring about desired Variation.<\/li>\n<\/ul>\n

                            Question 12.
                            \nWhat is Arificial Selection?
                            \nAnswer:<\/p>\n

                              \n
                            • It is a human involved process.<\/li>\n
                            • Having better crop from a mixed population.<\/li>\n
                            • The individuals differ in character.<\/li>\n<\/ul>\n

                              \"<\/p>\n

                              Question 13.
                              \nName the three types of Artificial Selection.
                              \nAnswer:
                              \na) Mass Selection,
                              \nb) Pureline Selection,
                              \nc) Clonal Selection<\/p>\n

                              Question 14.
                              \nWhat is Emasculation
                              \nAnswer:<\/p>\n

                                \n
                              • It is a process of removal of anthers to prevent self pollination before the opening of a flower.<\/li>\n<\/ul>\n

                                Question 15.
                                \nWhat are the various types of Mutagens?
                                \nAnswer:<\/p>\n

                                  \n
                                • Physical Mutagen – UV short wave, X-ray, Alpha, Beta and Gamma Waves.<\/li>\n
                                • Chemical Mutagen – Cesium, Ethylmethane sulfonate Nitromethyl and Urea.<\/li>\n<\/ul>\n

                                  \"<\/p>\n

                                  Question 16.
                                  \nWhat is Gamma Garden?
                                  \nAnswer:<\/p>\n

                                    \n
                                  • It is a form of mutation breeding.<\/li>\n
                                  • The Radioactive sources are cobalt – 60 and Caesium -137<\/li>\n
                                  • The first Gamma Garden in India is Bose Research institute at Calcutta.<\/li>\n<\/ul>\n

                                    Question 17.
                                    \nWhat are the benefits of polyploidy?
                                    \nAnswer:<\/p>\n

                                      \n
                                    • It often exhibit increase hybrid vigour.<\/li>\n
                                    • Increase the tolerance to both biotic and abiotic stresses<\/li>\n<\/ul>\n

                                      Question 18.
                                      \nHow Polyploidy can be induced? List out the products achieved through polyploidy.
                                      \nAnswer:<\/p>\n

                                        \n
                                      • Polyploidy can be induced by the use of cochicine to double the chromosome number.<\/li>\n
                                      • Seedless Tomato, Apple, Watermelon and orange.<\/li>\n<\/ul>\n

                                        \"<\/p>\n

                                        Question 19.
                                        \nDefine Green Revolution.
                                        \nAnswer:<\/p>\n

                                          \n
                                        • It is the cumulative result of a series of research, development, innovation and technology transfer initiatives in Agriculture.<\/li>\n<\/ul>\n

                                          Question 20.
                                          \nWrite about the contribution of Dr. M.S.Swaminathan in mutation breeding.
                                          \nAnswer:<\/p>\n

                                            \n
                                          • He is the pioneer mutation breeder.<\/li>\n
                                          • He has produce sharbati Sonora is the amber grain coloured variety of wheat.<\/li>\n
                                          • He is responsible for green revolution in India.<\/li>\n<\/ul>\n

                                            Question 21.
                                            \nWhat are the objectives considered in Breeding to improve the nutritional quality of plants?
                                            \nAnswer:
                                            \nTo improve protein, oil, vitamin, Micronutrient and mineral content and quality<\/p>\n

                                            \"<\/p>\n

                                            Question 22.
                                            \nTabulate certain crops and the pest resistant Variety?
                                            \nAnswer:<\/p>\n\n\n\n\n
                                            Crop<\/td>\nVariety<\/td>\nInsect pests<\/td>\n<\/tr>\n
                                            Brasica (rapeseed mustard)
                                            \nFlat been
                                            \nOkra (Bhindi)<\/td>\n                                            		Pusa Gaurav
                                            \nPusa Sem 2, Pusa Sem 3
                                            \nPusa Sawani, Pusa A<\/td>\n                                            		Aphids
                                            \nJassids, aphids and fruit borer
                                            \nShoot and Fruit borer<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

                                            Question 23.
                                            \nExpand the following.
                                            \nAnswer:<\/p>\n

                                              \n
                                            • CRISPR – Clustered Regularly Interspaced short Palindromic Repeats<\/li>\n
                                            • ODM – Oligonucleotide – Directed Mutagenesis.<\/li>\n<\/ul>\n

                                              Question 24.
                                              \nWhich method of artificial vegetative reproduction is good in plants. Give reason for your answer.
                                              \nAnswer:
                                              \nTissue culture is the modern artifical reproductive technique.<\/p>\n

                                              Reasons:<\/p>\n

                                                \n
                                              • \u00a0large scale production of clones (genitically uniform population) from the callus tissue – developed from the chosen explant cells (invitro)<\/li>\n
                                              • Both crop and tree species useful in forestry can be produced with desirable characters in large numbers with in a short span of time.<\/li>\n<\/ul>\n

                                                \"<\/p>\n

                                                Question 25.
                                                \nWhat are the advantages of rice field?
                                                \nAnswer:<\/p>\n

                                                  \n
                                                • Azolla is a free floating water fern that fixes atmospheric nitrogen in association with nitrogen fixing blue green algae. Anabaena azolla.<\/li>\n
                                                • It is used as a bio-fertilizer for wetland rice cultivation and is known to contribute 40-60 kh\/hal\/crop.<\/li>\n<\/ul>\n

                                                  Question 26.
                                                  \nWrite the any three names of plant species useful in green manure?
                                                  \nAnswer:<\/p>\n

                                                    \n
                                                  • Cassia fistula<\/li>\n
                                                  • Sesbania grandiflora<\/li>\n
                                                  • Azadirachta indica<\/li>\n<\/ul>\n

                                                    Question 27.
                                                    \nWhat is Bio-pesticides with example
                                                    \nAnswer:
                                                    \nBio-pesticides are biologically based agents used for the control of plant pests.
                                                    \nExample: Trichoderma.<\/p>\n

                                                    \"<\/p>\n

                                                    XI. Differentiate Type Questions<\/span><\/p>\n

                                                    Question 1.
                                                    \nDifferentiate Biofertilizers and Green manuring
                                                    \nAnswer:<\/p>\n\n\n\n\n\n\n
                                                    \n

                                                    Biofertilizers<\/p>\n<\/td>\n

                                                    		\n

                                                    Green Manure<\/p>\n<\/td>\n<\/tr>\n

                                                    It is defined aspreparations containing living or latent cells of efficient strains of micro organisms<\/td>\nIt is defined as the growing of green manure crops and use of these crops directly in the field by ploughing<\/td>\n<\/tr>\n
                                                    It helps the crops uptake of nutrients, when they are applied through seed or soil.<\/td>\nIt helps in increasing the content of nitrogen in the soil.<\/td>\n<\/tr>\n
                                                    In improve soil fertility and ecofriendly<\/td>\nIt helps in improving the structure and physical properties of the soil.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

                                                    Question 2.
                                                    \nDifferentiate Pureline selection and clonal selection
                                                    \nAnswer:<\/p>\n\n\n\n\n\n
                                                    Pureline Selection<\/td>\nClonal Selection<\/td>\n<\/tr>\n
                                                    It is a collection of plant obtained as a result of repeated self pollination from a single homozygous individual.<\/td>\nIt is asexually propagated and the clonal selection is employed to select improved variety from a mixed population.<\/td>\n<\/tr>\n
                                                    The progeny shows more. homozygosity with respect to all genes.<\/td>\nThe progeny resemble in genetic constitution with the parent plant as they are mitotically divided<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

                                                    \"<\/p>\n

                                                    Question 3.
                                                    \nDifferentiate Mutation Breeding and Polyploid Breeding
                                                    \nAnswer:<\/p>\n\n\n\n\n\n
                                                    Mutation Breeding<\/td>\nPolyploid Breeding<\/td>\n<\/tr>\n
                                                    Mutation means the sudden heritable changes in the genotype or phenotype<\/td>\nThe plants which possess more than two sets of chromosomes are called polyploids.<\/td>\n<\/tr>\n
                                                    It is of considerable importance in plant breeding as they provide essential inputs for evolution as well as for recombination and selection.<\/td>\nPoly ploidy often exhibit increased hybrid vigour and increased heterozygosity.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

                                                    Question 4.
                                                    \nDifferentiate Intervarietal and Interspecific Hybridization.
                                                    \nAnswer:<\/p>\n\n\n\n\n\n
                                                    Intervarietal Hybridization<\/td>\nInterspecific Hybridization<\/td>\n<\/tr>\n
                                                    The cross between the plants of two different varieties of the same species.<\/td>\nThe cross between the plants of two different species.<\/td>\n<\/tr>\n
                                                    This technique has been the basis of improving self pollinated as well as cross pollinated crops.<\/td>\nIt is commonly used for transferring the beneficial genes from one species to another.<\/p>\n

                                                     <\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

                                                    \"<\/p>\n

                                                    XII. Three marks<\/span><\/p>\n

                                                    Question 1.
                                                    \nWhat are the fields involved in Economic Botany?
                                                    \nAnswer:<\/p>\n

                                                      \n
                                                    • Agronomy, Anthropology, Archaeology, Chemistry, trade and commerce.<\/li>\n<\/ul>\n

                                                      Question 2.
                                                      \nDefine Domestication.
                                                      \nAnswer:<\/p>\n

                                                        \n
                                                      • It is the process of bringing a plant species under the control of humans and gradually changing it through careful selection.<\/li>\n<\/ul>\n

                                                        Question 3.
                                                        \nWhat is Organic Agriculture?
                                                        \nAnswer:<\/p>\n

                                                          \n
                                                        • It is as alternative agricultural system.<\/li>\n
                                                        • It is due to rapidly changing farming practices.<\/li>\n
                                                        • It is a production system that sustains the health of the soils, ecosystems and people.<\/li>\n
                                                        • It is based on ecological processes biodiversity and cycles adapted to local conditions<\/li>\n<\/ul>\n

                                                          \"<\/p>\n

                                                          Question 4.
                                                          \nWrite about the role played by Beauveria as a Bio-pesticide
                                                          \nAnswer:<\/p>\n

                                                            \n
                                                          • It is an entomo-pathogenic fungi<\/li>\n
                                                          • It acts as a parasite on various arthropod that causes white muscardine disease.<\/li>\n
                                                          • It also controls datnping off of tomato caused by Rhizoctonia Solani.<\/li>\n<\/ul>\n

                                                            Question 5.
                                                            \nDifferentiate Green manuring and Green leaf manuring.
                                                            \nGreen Manuring<\/p>\n

                                                              \n
                                                            • Growing of green manure crops and use these crops directly in the field by ploughing.<\/li>\n
                                                            • It increases the nitrogen in the soil.<\/li>\n
                                                            • It helps to improve the physical property of the soil.
                                                              \neg. Crotalaria juncea.<\/li>\n<\/ul>\n

                                                              Green Leaf Manuring<\/p>\n

                                                                \n
                                                              • Application of green leaves twigs, shrubs, plants growing in wasteland and field bunds.<\/li>\n
                                                              • The important plant species useful for green leaf manure are – cassia fistula. Delonix regia.<\/li>\n<\/ul>\n

                                                                \"<\/p>\n

                                                                Question 6.
                                                                \nDefine plant breeding
                                                                \nAnswer:<\/p>\n

                                                                  \n
                                                                • Plant breeding is the science of improvement of crop varities with higher yield better quality, resistance to diseases and shorter durations which are suitable to particular environment.<\/li>\n<\/ul>\n

                                                                  Question 7.
                                                                  \nWhat is the plan of thrid Agricultural Revolution
                                                                  \nAnswer:
                                                                  \nThe Green revolution or thrid Agricultural Revolution is the intensive plan of 1960’s to increase crop yield in developing countries by introducing the high yielding, resistant varieties, increased irrigation facilities, fertilizer application and better agricultural management.<\/p>\n

                                                                  Question 8.
                                                                  \nDraw a flow chart showing the steps involved in plant Breeding.
                                                                  \nAnswer:
                                                                  \nThe main steps in plant breeding are given below
                                                                  \n\"Samacheer<\/p>\n

                                                                  Question 9.
                                                                  \nWrite about NBPG R
                                                                  \nAnswer:<\/p>\n

                                                                    \n
                                                                  • It is responsible for introduction and maintence of germplasm of various agricultural and horticultural station in our country.<\/li>\n
                                                                  • It is also responsible for maintenance of plant materials of botanical and medicinal interest.<\/li>\n
                                                                  • It is located at Rangpuri\/New Delhi with four regional station at Amristar, Kolkata, Mumbai and Chennai.<\/li>\n<\/ul>\n

                                                                    \"<\/p>\n

                                                                    Question 10.
                                                                    \nDraw the Schematic difference between Mass & Pureline selection.
                                                                    \nAnswer:
                                                                    \n\"Samacheer<\/p>\n

                                                                    Question 11.
                                                                    \nWhat is hybridization?
                                                                    \nAnswer:<\/p>\n

                                                                      \n
                                                                    • Hybridization is the method of producing new crop verities by crossing of plants that are genetically different.<\/li>\n
                                                                    • It offers improvement in crop by combining the desirable character of two or more varities.<\/li>\n
                                                                    • The first natural hybridization was observed by Cotton Mather in maize.<\/li>\n<\/ul>\n

                                                                      Question 12.
                                                                      \nA type of Heterosis is called as Pseudoheterosis – Why?
                                                                      \nAnswer:<\/p>\n

                                                                        \n
                                                                      • It is called as pseudoheterosis because the progeny is superior over parents by vegetative growth.<\/li>\n
                                                                      • They are usually sterile.<\/li>\n
                                                                      • It is also called as Luxuriance.<\/li>\n<\/ul>\n

                                                                        \"<\/p>\n

                                                                        Question 13.
                                                                        \nTabulate certain crop variety and the disease to which they are resistant.
                                                                        \nAnswer:<\/p>\n\n\n\n\n\n\n\n\n
                                                                        Crop<\/td>\nVariety<\/td>\nResistance to diseases<\/td>\n<\/tr>\n
                                                                        Wheat<\/td>\nHimgiri<\/td>\nLeaf and Stripe rust, hill bunt<\/td>\n<\/tr>\n
                                                                        Brassica<\/td>\nPusa swarnim (Kara rai)<\/td>\nWhite rust<\/td>\n<\/tr>\n
                                                                        Cauliflower<\/td>\nPusa Shubhra, Pusa snowball K-1<\/td>\nBlack rot and curl blight black rot.<\/td>\n<\/tr>\n
                                                                        Cowpea<\/td>\nPusa Komal<\/td>\nBacterial blight<\/td>\n<\/tr>\n
                                                                        Chilli<\/td>\nPusa Sadabahar<\/td>\nChilly mosaic virus, Tobacco mosaic virus and Leaf curl.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

                                                                        Question 14.
                                                                        \nWhat is Norm 10?<\/p>\n

                                                                          \n
                                                                        • It is dwarfing genes with high photosynthetic rate and increases the respiratory activity.<\/li>\n
                                                                        • Gonjiro Inazuka was scientist, who selected the Semi- dwarf wheat variety – Norm 1o.<\/li>\n
                                                                        • This variety helped one billion lives from hunger and starvation.<\/li>\n<\/ul>\n

                                                                          Question 15.
                                                                          \nHow can we develop resistance to Insect pests in plants?<\/p>\n

                                                                            \n
                                                                          • Insect resistance in host crop plants may be due to morphological, biochemical 0r physiological characteristics.<\/li>\n
                                                                          • Hairy leaves in plants – Jassids in cotton
                                                                            \n– Cereal leaf bettle in wheat.<\/li>\n
                                                                          • Solids Stem – Stem sawfly.
                                                                            \nSmooth leaves and nectar less cotton – Bol worms.
                                                                            \nHigh aspartic acid, low nitrogen and sugar content – Maize stem borers.<\/li>\n<\/ul>\n

                                                                            \"<\/p>\n

                                                                            Question 16.
                                                                            \nWhat are the plant breeding tools used to improve the crop varieties?
                                                                            \nAnswer:<\/p>\n

                                                                              \n
                                                                            • Genetic Engineering, plant tissue culture, protoplasmic fusion, Molecular marking and DNA finger printing.<\/li>\n<\/ul>\n

                                                                              Question 17.
                                                                              \nDefine mutation breeding?
                                                                              \nAnswer:
                                                                              \nMutation means the sudden heritable changes in the genotype or phenotype of an organism.<\/p>\n

                                                                              Question 18.
                                                                              \nWhat is Bio-fortification?
                                                                              \nAnswer:
                                                                              \nBreeding crops with higher levels of vitamins and minerals or higher protein and healthier fats is the most practical means to improve public health.<\/p>\n

                                                                              \"<\/p>\n

                                                                              Question 19.
                                                                              \nComment on sugercane.
                                                                              \nAnswer:<\/p>\n

                                                                                \n
                                                                              • Saccharum bareri was originally grown in north India.<\/li>\n
                                                                              • It is poor sugar content and yield.<\/li>\n
                                                                              • Tropical canes grown in south India saccharurn officinarum had thicker stems and higher sugar content.<\/li>\n
                                                                              • It did not grow well in North India<\/li>\n
                                                                              • These two species were successfully crossed to get sugar cane varieties combining the desirable qualities of high yield thick stems high sugar and ability to grows in the sugar cane areas of North India.<\/li>\n<\/ul>\n

                                                                                XIII. Five Marks<\/span><\/p>\n

                                                                                Question 1.
                                                                                \nWhat are the possible changes in the plant due to domestication?
                                                                                \nAnswer:<\/p>\n

                                                                                  \n
                                                                                • Adaption to the environmental alteration.<\/li>\n
                                                                                • Adaption to wider geographical range.<\/li>\n
                                                                                • Uniformity in flowering and fruiting.<\/li>\n
                                                                                • Increased size of fruits and seeds.<\/li>\n
                                                                                • Change in breeding system.<\/li>\n
                                                                                • Increase in yield.<\/li>\n
                                                                                • Increased resistance for disease and pest.<\/li>\n
                                                                                • Developing seedless parthenocarpic fruit.<\/li>\n
                                                                                • Enhancing the taste and nutritional composition.<\/li>\n<\/ul>\n

                                                                                  Question 2.
                                                                                  \nEnumerate the History of Agriculture:
                                                                                  \nAnswer:<\/p>\n

                                                                                    \n
                                                                                  • 1807 – Alexander Yon Humboldt considered that original & source of most and their origin is an importable secret.<\/li>\n
                                                                                  • 1868 – Darwin’s theory proposed that natural selection and hybridization led to the origin of cultivate plants.<\/li>\n
                                                                                  • 1883 – De Candolle studied 247 cultivated plants species and was able to find the ancestral form, region of domestication and history.<\/li>\n
                                                                                  • 1887-1943 – Vavilov studied about the diverse forms of plants based on various criteria like morphology,cytology etc., He proposed 8 geographic centres and later developed it to 12 centres.<\/li>\n
                                                                                  • 1968 – Zhukovsky put forward the concept of mega gene and divided the whole world into 12 mega gene centres.<\/li>\n
                                                                                  • 1971 – Harlen believed that agriculture originated independently in three different areas.
                                                                                    \n– There were non centres are the area were the crop has been shifted.<\/li>\n<\/ul>\n

                                                                                    \"<\/p>\n

                                                                                    Question 3.
                                                                                    \nTabulate the vavilov’s centres of crop origin and crop domesticated.
                                                                                    \nAnswer:
                                                                                    \nVavilov’s centres of crop origin and crops domesticated.<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
                                                                                    Vavilov’s centre of crop origin<\/td>\nCrops domesticated<\/td>\n<\/tr>\n
                                                                                    1. China<\/td>\nFoxtail millet, soybean, bamboo, onion, .crucifers<\/td>\n<\/tr>\n
                                                                                    2. India<\/td>\nRice, Sugarcane, mango, orange, eggplant, sesame<\/td>\n<\/tr>\n
                                                                                    2a. South East Asia<\/td>\nRice, banana, coconut, clove, hemp.<\/td>\n<\/tr>\n
                                                                                    3. Central East<\/td>\nWheat, pea, hemp, cotton, etc.,<\/td>\n<\/tr>\n
                                                                                    4. The Near East<\/td>\nWheat, rye, many subtropical and tropical fruits<\/td>\n<\/tr>\n
                                                                                    5. Mediterranean<\/td>\nOlive, vegetables, oil, yielding plants, wheats<\/td>\n<\/tr>\n
                                                                                    6. Ethiopia (Abyssinian)<\/td>\nWheat, barley, sesame, castor, coffee<\/td>\n<\/tr>\n
                                                                                    7. Mesomerica (South Mexican & central American centre)<\/td>\nMaize, bean, sweet potato, papaya, guava,
                                                                                    \ntobacco<\/td>\n<\/tr>\n
                                                                                    8. South America<\/td>\nTomato, pine-apple<\/td>\n<\/tr>\n
                                                                                    8a. South America<\/td>\nPotato<\/td>\n<\/tr>\n
                                                                                    8b. The Brazilian-Paraguayan centre<\/td>\nGroundnut, cashew nut, pine apple, peppers, rubber.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

                                                                                    Question 4.
                                                                                    \nWrite an essay on Indian plant Breeders.
                                                                                    \nAnswer:<\/p>\n

                                                                                      \n
                                                                                    • Dr.M.S.Swaminathan- He is pioneer in mutation breeder.<\/li>\n
                                                                                    • Sir.T.S.Venkatraman- An eminent sugarcane breeder.<\/li>\n
                                                                                    • Dr.B.P.Pal-Developed superior disease resistant varieties of wheat<\/li>\n
                                                                                    • Dr.K.Ramiah- Eminent Rice Breeder.
                                                                                      \nN.G.P.Rao-An eminent sorghum breeder, developed world’s first hybrid of sorghum (CSH-1).<\/li>\n
                                                                                    • C.T.Patel-Developed world’s first cotton hybrid.<\/li>\n
                                                                                    • Choudhary Ram Dhan – wheat breeder,developed C-591 wheat which made Punjab as wheat granary of india.<\/li>\n<\/ul>\n

                                                                                      \"<\/p>\n

                                                                                      Question 5.
                                                                                      \nDifferentiate Rhizobium from Azolla as bio-fertilizers.
                                                                                      \nAnswer:<\/p>\n

                                                                                        \n
                                                                                      • Bio-fertilizers could also be called as microbial cultures or bacteria) fertilizers.<\/li>\n
                                                                                      • They are efficient in fixing nitrogen improve soil fertility, eco-friendly and cost effective.<\/li>\n<\/ul>\n

                                                                                        Rhizobium:<\/p>\n

                                                                                          \n
                                                                                        • It resides in the root nodules of leguminous plants.<\/li>\n
                                                                                        • It fixes the atmospheric Nitrogen.<\/li>\n
                                                                                        • It increases yield of paddy by 15-40%<\/li>\n<\/ul>\n

                                                                                          Azolla:<\/p>\n

                                                                                            \n
                                                                                          • Free floating water fern, with blue green algae fixes the Nitrogrn.<\/li>\n
                                                                                          • It increases the yield of rice.<\/li>\n
                                                                                          • It decomposes quickly.<\/li>\n<\/ul>\n

                                                                                            Arbuscular Mycorrhizae:<\/p>\n

                                                                                              \n
                                                                                            • They can dissolve the phosphates found in the soil.<\/li>\n
                                                                                            • It provides strength to resist disease, germ and unfavourable weather.<\/li>\n<\/ul>\n

                                                                                              Seaweed Liquid Fertilizer:<\/p>\n

                                                                                                \n
                                                                                              • It contains cytokinin, gibberellins and Auxin<\/li>\n
                                                                                              • Most of it are made from kelp ( Brown Algae).<\/li>\n
                                                                                              • The alginates in it react with metals in soil and retain moisture for a long time.<\/li>\n
                                                                                              • They have more than 70 minerals vitamin and enzymes.<\/li>\n
                                                                                              • Seeds soaked in seaweed germinate rapidly.<\/li>\n<\/ul>\n

                                                                                                Question 6.
                                                                                                \nTabulate the classification of Biofertilizers.
                                                                                                \nAnswer:
                                                                                                \n\"Samacheer<\/p>\n

                                                                                                Question 7.
                                                                                                \nDiscuss about Biopesticides in detail.
                                                                                                \nAnswer:<\/p>\n

                                                                                                  \n
                                                                                                • They are biologically based agents used for the control of plant pests.<\/li>\n
                                                                                                • They are ecofriendly , Non – toxic and cheaper the chemical pesticide.<\/li>\n<\/ul>\n

                                                                                                  Trichoderma:<\/p>\n

                                                                                                    \n
                                                                                                  • They are free living fungi in the soil.<\/li>\n
                                                                                                  • They control plant disease.<\/li>\n
                                                                                                  • It has the ability to enhance root growth development.<\/li>\n
                                                                                                  • Increases the crop productivity.<\/li>\n
                                                                                                  • It helps in resisting Abiotic stress.<\/li>\n
                                                                                                  • It increases the uptake and use of nutrients.<\/li>\n<\/ul>\n

                                                                                                    Beauveria:<\/p>\n

                                                                                                      \n
                                                                                                    • It is an entomo – pathogenic fungus<\/li>\n
                                                                                                    • It parasitse arthropods that cause white muscardine and controls damping off of tomato<\/li>\n<\/ul>\n

                                                                                                      \"<\/p>\n

                                                                                                      Question 8.
                                                                                                      \nEnumerate the objectives of plant Breeding.
                                                                                                      \nAnswer:<\/p>\n

                                                                                                        \n
                                                                                                      • To increase yield, Vigour and fertility of the crop.<\/li>\n
                                                                                                      • To increase tolerance to environmental condition, Salinity, Temperature and drought.<\/li>\n
                                                                                                      • To prevent premature falling of buds fruits etc.,<\/li>\n
                                                                                                      • To improve the maturation of both the male and female gametes at the same time.<\/li>\n
                                                                                                      • To develop resistance to pathogens and pests.<\/li>\n
                                                                                                      • To develop photosensitive and thermos – Sensitive Varieties.<\/li>\n<\/ul>\n

                                                                                                        Question 9.
                                                                                                        \nDiscuss about the types of selection.
                                                                                                        \nAnswer:<\/p>\n

                                                                                                          \n
                                                                                                        • Selection is the oldest and basic method of plant breeding.<\/li>\n
                                                                                                        • There are two main types of selection – Natural and Artificial.<\/li>\n<\/ul>\n

                                                                                                          Natural Selection:<\/p>\n

                                                                                                            \n
                                                                                                          • It occurs naturally.<\/li>\n
                                                                                                          • It takes longer time in bringing about desired variation.<\/li>\n
                                                                                                          • It reflected the Darwinian principle.<\/li>\n<\/ul>\n

                                                                                                            Artificial Selection:<\/p>\n

                                                                                                              \n
                                                                                                            • It is a human involved process.<\/li>\n
                                                                                                            • Producing better crop from a mixed population.<\/li>\n<\/ul>\n

                                                                                                              a) Mass Selection :<\/p>\n

                                                                                                                \n
                                                                                                              • Large number of plants of similar phenotype are selected and crossed to get a new variety.<\/li>\n
                                                                                                              • After repeated selection for five to six years it is distributed to the farmers.<\/li>\n<\/ul>\n

                                                                                                                b) Pureline Selection:<\/p>\n

                                                                                                                  \n
                                                                                                                • Plants obtained as a result of self pollination from a single homozygous individual.<\/li>\n
                                                                                                                • The progeny shows homozy gosity with respect to all genes.<\/li>\n
                                                                                                                • New Genotypes are never created,<\/li>\n<\/ul>\n

                                                                                                                  c) Clonal Seection:<\/p>\n

                                                                                                                    \n
                                                                                                                  • The progenies that are asexually propagated resembles the parent genetically.<\/li>\n
                                                                                                                  • The progeny is multiplied to form clone.<\/li>\n
                                                                                                                  • The genotype of a clone remains unchanged for a long period of time.<\/li>\n<\/ul>\n

                                                                                                                    \"<\/p>\n

                                                                                                                    Question 10.
                                                                                                                    \nDescribe the steps involved in Hybri-dization.
                                                                                                                    \nAnswer:
                                                                                                                    \na) Selection of Parents :<\/p>\n

                                                                                                                      \n
                                                                                                                    • Male and female plants of desired characters are selected.<\/li>\n
                                                                                                                    • It should be tested for their homozygosity<\/li>\n<\/ul>\n

                                                                                                                      b) Emasculation:<\/p>\n

                                                                                                                        \n
                                                                                                                      • It is removal of anther before blooming.<\/li>\n
                                                                                                                      • It avoids self pollination<\/li>\n<\/ul>\n

                                                                                                                        c) Bagging:
                                                                                                                        \nThe stigma is protected against any undesirable pollen grains, by covering with a bag.<\/p>\n

                                                                                                                        d) Crossing:
                                                                                                                        \nTransfer of pollen grains from selected male flower to the stigma of the emasculated female flower.<\/p>\n

                                                                                                                        e) Harvesting Seeds and Raising Plants :<\/p>\n

                                                                                                                          \n
                                                                                                                        • Due to fertilization seeds form.<\/li>\n
                                                                                                                        • These seeds are grown into a new generation.<\/li>\n<\/ul>\n

                                                                                                                          Question 11.
                                                                                                                          \nDiscuss about the types of heterosis.
                                                                                                                          \nAnswer:
                                                                                                                          \na) Euheterosis:<\/p>\n

                                                                                                                            \n
                                                                                                                          • It is the true heterosis.<\/li>\n
                                                                                                                          • It is inherited<\/li>\n<\/ul>\n

                                                                                                                            b) Mutational Euheterosis :<\/p>\n

                                                                                                                              \n
                                                                                                                            • It is the simplest form.<\/li>\n
                                                                                                                            • Removal of harmful, recessive, mutant genes by superior dominant allele in cross pollinated crops.<\/li>\n<\/ul>\n

                                                                                                                              c) Balanced Euheterosis:<\/p>\n

                                                                                                                                \n
                                                                                                                              • Well balanced gene combination.<\/li>\n
                                                                                                                              • More adaptive to environment and agricultural usefulness.<\/li>\n<\/ul>\n

                                                                                                                                d) Psuedo heterosis :<\/p>\n

                                                                                                                                  \n
                                                                                                                                • Also known as luxuriance.<\/li>\n
                                                                                                                                • Progeny possess superiority over parents in regetative Growth.<\/li>\n
                                                                                                                                • But not in yield & adaptation.<\/li>\n
                                                                                                                                • Usually sterile or poorly fertile.<\/li>\n<\/ul>\n

                                                                                                                                  \"<\/p>\n

                                                                                                                                  Question 12.
                                                                                                                                  \nDescribe polyploid Breeding.
                                                                                                                                  \nAnswer:<\/p>\n

                                                                                                                                    \n
                                                                                                                                  • The plants which posses more than two sets of chromosomes are called Polyploids.<\/li>\n
                                                                                                                                  • It is the major force in the evolution of both wild and cultivated plants.<\/li>\n
                                                                                                                                  • Polyploid of exhibit hybrid vigour.<\/li>\n
                                                                                                                                  • Increases tolerance to biotic and abiotic stresses.<\/li>\n
                                                                                                                                  • Polyploidy results in reduced fertility and producing seedless varieties.<\/li>\n
                                                                                                                                  • If chromosomes is doubled by itself it is autopolyploidy.<\/li>\n
                                                                                                                                  • Triploid condition in Sugarbeets result in Vigour.<\/li>\n
                                                                                                                                  • Colchicine used to double the chromosomes. Eg. Triticale and Raphanobrassica<\/li>\n<\/ul>\n

                                                                                                                                    Question 13,
                                                                                                                                    \nBiofortification is the breeding crops with
                                                                                                                                    \nhigher levels of nutrients. Justify it..
                                                                                                                                    \nAnswer:
                                                                                                                                    \nBreeding of improved nutritional quality like
                                                                                                                                    \n– Protein content and quality.
                                                                                                                                    \n– Oil content and quality
                                                                                                                                    \n– Vitamin Content
                                                                                                                                    \n– Micro & Macro nutrient content.<\/p>\n

                                                                                                                                      \n
                                                                                                                                    • In 2000 – Maize hybrid had twice the nutrient value than the parents.<\/li>\n
                                                                                                                                    • Wheat – Atlass 66 having high protein content.<\/li>\n
                                                                                                                                    • Iron fortified rice can be developed.<\/li>\n
                                                                                                                                    • Vitamin A enriched vegetable.<\/li>\n
                                                                                                                                    • Vitamin C enriched vegetables and iron and calcium crops also developed.<\/li>\n<\/ul>\n

                                                                                                                                      Question 14.
                                                                                                                                      \nEnumerate the New Breeding Techniques.
                                                                                                                                      \nAnswer:<\/p>\n

                                                                                                                                        \n
                                                                                                                                      • It is a collection of methods that could increase the development of new traits in plant breeding.<\/li>\n
                                                                                                                                      • It often involve genome editing.<\/li>\n
                                                                                                                                      • Cutting and modifying the genome during the repair process by tools like CRISPR.<\/li>\n
                                                                                                                                      • Genome editing to introduce changes in few base pairs using a technique called ODM.<\/li>\n
                                                                                                                                      • Transferring a gene from an identical or closely related species (Cisgenesis)<\/li>\n
                                                                                                                                      • Organising process that alter gene activity without altering the DNA itself.<\/li>\n<\/ul>\n

                                                                                                                                        \"<\/p>\n

                                                                                                                                        Question 15.
                                                                                                                                        \nRamu and Somu are farmers. Ramu cultivated the crops by self fertilization method. Somu cultivated the crops from mixed population.
                                                                                                                                        \n(i) Who will get new variety?
                                                                                                                                        \n(ii) Write the advantage and disadvantages of their selection.
                                                                                                                                        \nAnswer:
                                                                                                                                        \n(i) Somu will get the new variety. Because he had selected the mixed population method.<\/p>\n

                                                                                                                                        (ii) Advantages of self fertilization method:
                                                                                                                                        \nThe repeated self pollination from a single homozygous individual produces a variety that shows more homozygosity with respect to all genes.<\/p>\n

                                                                                                                                        (iii) Dis advantages:<\/p>\n

                                                                                                                                          \n
                                                                                                                                        • The major disadvantage of this type is that it never creates new genotypes.<\/li>\n
                                                                                                                                        • The plants produced are also less adaptible and less stable to the environmental fluctuations.<\/li>\n<\/ul>\n

                                                                                                                                          Advantages of Mixed population method
                                                                                                                                          \nIn this method, a large number of plants of similar phenotype (or) morphological characters are selected and their seeds are mixed together to constitute a newer variety’.<\/p>\n

                                                                                                                                          Disadvantages:
                                                                                                                                          \nThe disadvantage of mixed population method is that it is difficult to distinguish the hereditary variation from environmental variation .<\/p>\n

                                                                                                                                          Question 16.
                                                                                                                                          \nMention the benefits of seed treatment?
                                                                                                                                          \nAnswer:<\/p>\n

                                                                                                                                            \n
                                                                                                                                          • Prevents spread of plant disease<\/li>\n
                                                                                                                                          • Protects seed from seedling blights<\/li>\n
                                                                                                                                          • Improves germination<\/li>\n
                                                                                                                                          • Improves germination<\/li>\n
                                                                                                                                          • provides protection from storage insects<\/li>\n
                                                                                                                                          • controls soil insects.<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"

                                                                                                                                            Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Bio Botany Guide Pdf Chapter 9 Plant Breeding Text Book Back Questions and Answers, Notes. Tamilnadu Samacheer Kalvi 12th Bio Botany Solutions Chapter 9 Plant Breeding 12th Bio Botany Guide Plant Breeding Text Book Back Questions and Answers I. Choose the correct answer Question 1. Assertion : …<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"spay_email":""},"categories":[5],"tags":[],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/samacheer-kalvi.com\/wp-json\/wp\/v2\/posts\/25328"}],"collection":[{"href":"https:\/\/samacheer-kalvi.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/samacheer-kalvi.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/samacheer-kalvi.com\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/samacheer-kalvi.com\/wp-json\/wp\/v2\/comments?post=25328"}],"version-history":[{"count":1,"href":"https:\/\/samacheer-kalvi.com\/wp-json\/wp\/v2\/posts\/25328\/revisions"}],"predecessor-version":[{"id":47936,"href":"https:\/\/samacheer-kalvi.com\/wp-json\/wp\/v2\/posts\/25328\/revisions\/47936"}],"wp:attachment":[{"href":"https:\/\/samacheer-kalvi.com\/wp-json\/wp\/v2\/media?parent=25328"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/samacheer-kalvi.com\/wp-json\/wp\/v2\/categories?post=25328"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/samacheer-kalvi.com\/wp-json\/wp\/v2\/tags?post=25328"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}