Class 12th Biology 2014 Set1 Delhi Board Paper Solution
Question 23
(a) Name the tropical sugar cane variety grown in South India. How has it helped in improving the sugar cane quality grown in North India?
(b) Identify 'a', 'b' and 'c' in the following table:
| No | Crop | Variety | Insect Pests |
| 1 | Brassica | Pusa Gaurav | (a) |
| 2 | Flat bean | Pusa Sem 2 Pusa sem 3 |
(b) |
| 3 | (c) | Pusa Sawani Pusa A-4 |
Shoot and fruit borer |
Answer
(i) The tropical sugarcane variety grown in Southern India is Saccharum officinarum which has a thicker stem and high sugar content; however, it cannot grow in Northern India. Saccharum barberi is a natively grown in Northern India.
These two varieties were crossed to get the desirable qualities of both (higher sugar content, thicker stem and the ability to grow in Northern India).
(ii)
| No | Crop | Variety | Insect Pests |
| 1 | Brassica | Pusa Gaurav | Aphids |
| 2 | Flat bean | Pusa Sem 2 Pusa sem 3 |
Jassids and fruit borer |
| 3 | Okra (Bhindi) | Pusa Sawani Pusa A-4 |
Shoot and fruit borer |
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