Select out the odd one with respect to discovery of plant growth regulators ?

Options

A. Coleoptile of oat – Auxin
B. Bakane disease – GA
C. Yeast extract – cytokinin
D. Ripened Grapes – Ethylene

Answer

To solve the question of selecting the odd one out with respect to the discovery of plant growth regulators, we need to analyze the options provided (though they are not explicitly listed in the transcript). Here’s a step-by-step approach to arrive at the solution:

### Step 1: Understand Plant Growth Regulators
Plant growth regulators, also known as plant hormones, are substances that regulate various aspects of plant growth and development. The major types include auxins, cytokinins, gibberellins, abscisic acid, and ethylene.

### Step 2: Identify Key Discoveries Related to Each Hormone
- **Auxins**: Discovered through experiments with coleoptiles (the protective sheath covering the emerging shoot in grasses). The bending of coleoptiles towards light (phototropism) was a key observation.
- **Cytokinins**: Discovered in relation to cell division and growth, particularly noted in the context of plant tissue culture and the promotion of shoot formation.
- **Ethylene**: Recognized for its role in the ripening of fruits, particularly in relation to ripe grapes.

### Step 3: Analyze the Context of Each Discovery
Each of these hormones has a specific context or mechanism through which they were discovered:
- Auxins were discovered through light response (phototropism).
- Cytokinins were linked to cell division and growth in tissue culture.
- Ethylene was discovered through its effect on fruit ripening.

### Step 4: Identify the Odd One Out
To find the odd one out, we need to look for a hormone that does not fit the pattern of discovery or mechanism:
- If one of the options relates to a different mechanism or is not primarily associated with growth regulation in the same way as the others, that would be the odd one out.

### Conclusion
Without the specific options provided in the question, it is challenging to definitively identify the odd one out. However, based on the context given in the transcript, if we assume that all options relate to the plant hormones mentioned, the odd one could be one that does not fit the growth regulation theme or is not primarily recognized for its role in plant growth.