Class 12th Biology 2018 Set1 Delhi Board Paper Solution
Question 9
You have obtained a high yielding variety of tomato. Name and explain the procedure that ensures retention of the desired characteristics repeatedly in large populations of future generations of the tomato crop.
Answer
Plant breeding is the purposeful manipulation of plant species in order to create desired plant types which are better suited for cultivation, give better yields and are disease resistant. Main steps in breeding a new genetic variety of a crop:
(a) Collection of variability
(b) Evaluation and selection of parents
(c) Cross hybridisation among selected parents
(d) Selection and testing of superior recombinants
(e) Testing, release and commercialisation of new cultivars
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