In mung bean , resistance to yellow mosaic virus and powdery mildew were induced by

Options

A. Polyploidy
B. Mutations
C. Selection
D. Hybridisation

Answer

### Step-by-Step Solution:

1. **Identify the Problem**: The question asks about the method used to induce resistance to yellow mosaic virus and powdery mildew in mung bean plants.

2. **Understand the Context**: Yellow mosaic virus and powdery mildew are diseases that affect mung bean crops. Resistance to these diseases is crucial for improving crop yield and sustainability.

3. **Consider the Methods of Induction**: There are various methods to induce resistance in plants, including:
- **Mutation Breeding**: This involves inducing mutations in the plant's genome to create variations that may confer resistance to diseases.
- **Selection**: This process involves choosing plants with desirable traits for further breeding.
- **Hybridization**: This is the crossing of different species or varieties to produce hybrids with superior traits.
- **Polyploidy**: This refers to the condition of having more than two complete sets of chromosomes, which can lead to increased vigor in plants.

4. **Focus on the Relevant Method**: In the case of mung bean, the resistance to yellow mosaic virus and powdery mildew is specifically induced through mutation breeding. This method creates genetic variations that can lead to disease resistance.

5. **Conclude the Answer**: Therefore, the correct answer is that resistance to yellow mosaic virus and powdery mildew in mung bean was induced by **mutation breeding**.

### Final Answer:
In mung bean, resistance to yellow mosaic virus and powdery mildew was induced by **mutation breeding**.

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