Question

K. J. Kasha and coworkers found that following the cross between Hordeum vulgare \(\times\) Hordeum bulbosum, chromosomes of H. bulbosum were eliminated in early zygotic division, so few days after pollination, embryos can be cultured to get haploids. This method is called as -

• A. Delayed pollination
• B. Distant hybridization
• C. Nucellus culture
• D. Androgenesis

Hint:

When you see a cross between two different species (like {H. vulgare} and {H. bulbosum}), the overarching term for the technique is {Distant Hybridization}. The specific outcome here is haploid production, but the method itself is hybridization.

Answer 1

The Correct Option is B

Step 1: Concept Overview:
The question concerns a technique used to create haploid barley plants (Hordeum vulgare), specifically asking for the name of the method.
Step 2: Detailed Explanation:
The process involves:
An interspecific or distant hybridization between Hordeum vulgare (cultivated barley) and Hordeum bulbosum (a wild relative). This cross between different species is key.
Selective elimination of H. bulbosum chromosomes occurs after fertilization in the developing embryo.
The result is a haploid embryo containing only H. vulgare chromosomes, which is then rescued and cultured in vitro to produce a haploid plant.
This technique leverages distant hybridization to produce haploids via chromosome elimination.
Nucellus culture involves cloning from maternal tissue.
Androgenesis is haploid production derived from male gametes (pollen).
Step 3: Conclusion:
This haploid production method, employing an interspecific cross and subsequent chromosome elimination, exemplifies distant hybridization.