Question

Which combination of strategies forms the basis of in vivo haploid induction technologies in plants?
A. induction of parthenogenesis
B. culture of anthers or ovules
C. use of paternal inducer lines
D. uniparental genome elimination
Choose the correct answer from the options given below:

• A. A, B and C only
• B. B, C and D only
• C. A, C and D only
• D. B, and D only

Hint:

To solve this, focus on the distinction between {in vivo} (in the plant) and {in vitro} (in the lab). Any mention of "culture" (like anther culture) immediately points to an {in vitro} method.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
The question asks to identify the methods used for in vivo haploid induction. In vivo means the process occurs within a living plant, as opposed to in vitro, which means "in glass" (i.e., in a lab culture).
Step 2: Detailed Explanation:
Let's analyze each strategy:
A. induction of parthenogenesis: This is the development of an embryo from an unfertilized egg. This process occurs naturally or can be induced in vivo within the ovule of the parent plant. (Correct - In vivo)
B. culture of anthers or ovules: This involves excising plant parts (anthers or ovules) and growing them on an artificial medium in a lab. This is the definition of an in vitro technique. (Incorrect - In vitro)
C. use of paternal inducer lines: This is a modern technique, especially in maize, where pollination by a special "inducer" line triggers the development of a haploid embryo from the female gamete. The entire process up to embryo formation happens in vivo on the mother plant. (Correct - In vivo)
D. uniparental genome elimination: This is the biological mechanism that underlies haploid induction through paternal inducer lines and also through distant hybridization. After fertilization, the chromosomes of one parent are selectively eliminated from the zygote. This elimination process occurs in vivo during the early stages of embryo development. (Correct - In vivo)
Therefore, the combination of strategies that form the basis of in vivo haploid induction are A, C, and D.
Step 3: Final Answer:
The correct combination is A, C and D only.