Class 12th Biology 2017 Set1 Delhi Board Paper Solution
Question 8
In an agricultural field, there is a prevalence of the following organisms and crop diseases which are affecting the crop yield badly:
(a) White rust (b) Leaf and stripe rust (c) Black rot (d) Jussids
Recommend the varieties of crops the farmers should grow to get rid of the existing problem and thus, improve the crop yield.
Answer
Normal varieties of crops are prone to infection by various pathogens which lead to poor growth of crops. To get rid of existing problems, the farmers should grow improved hybrid varieties as these are mostly resistant to most pathogens and give higher yield.
| White rust | Pusa Swarnim (karan rai) | Brassica |
| leaf and stripe rust | Himgiri | Wheat |
| Black rot | Pusa Swarnim, Pusa snowball K-1 | Cauliflower |
| Jassids | Pusa Sem-2 | Flat Bean |
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