Read the following statements carefully and find out the set of correct statements
a. Suspension culture requires constant stirring at the rate of `100-250` rpm.
b. Development of diseases in a plant depends on the interactions between host genotype and environment, but not on pathogen genotype
c. Black rot of crucifers and red rot of sugarcane are diseasescaused by fungi.
d. It is expected that 125 g of Methylophilus methylotrophus produces 12.5 tonnes of protein per day.

Options

A. b,c
B. a,d
C. b,d
D. c,d

Answer

To determine the set of correct statements from the provided options, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement A**: "Suspension culture requires constant stirring at the rate of 100-250 rpm."
- **Analysis**: Suspension culture involves keeping cells suspended in a liquid medium, which indeed requires constant agitation to maintain uniformity. The typical stirring rate for suspension cultures is between 100 to 250 rpm.
- **Conclusion**: This statement is **correct**.

2. **Statement B**: "Development of diseases in a plant depends on the interactions between host genotype and environment, but not on pathogen genotype."
- **Analysis**: The development of plant diseases is influenced by the interaction of three factors: host genotype, environmental conditions, and pathogen genotype. Therefore, stating that it does not depend on pathogen genotype is incorrect.
- **Conclusion**: This statement is **incorrect**.

3. **Statement C**: "Black rot of crucifers and red rot of sugarcane are diseases caused by fungi."
- **Analysis**: Black rot of crucifers is caused by the bacterium *Xanthomonas*, while red rot of sugarcane is indeed caused by a fungus (*Glomerella*). Since one of the diseases mentioned is caused by bacteria, this statement is incorrect.
- **Conclusion**: This statement is **incorrect**.

4. **Statement D**: "It is expected that 125 g of Methylophilus methylotrophus produces 12.5 tonnes of protein per day."
- **Analysis**: *Methylophilus methylotrophus* is known for its ability to produce a significant amount of protein, and the figure mentioned aligns with its potential as a source of single-cell protein. Therefore, this statement is correct.
- **Conclusion**: This statement is **correct**.

### Summary of Findings:
- **Correct Statements**: A and D
- **Incorrect Statements**: B and C

### Final Answer:
The correct set of statements is A and D.

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