Which statement is not correct :-

Options

A. Plastid inheritance in mirabilis jalapa is a true example of cytoplasmic inheritance
B. Inheritance of cytogene occurs only through female
C. In cytoplasmic inheritance, reciprocal cross can affect results
D. True cytoplasmic inheritance is due to karyogene

Answer

To determine which statement is not correct regarding cytoplasmic inheritance, we will analyze each statement provided in the question step by step.

### Step-by-Step Solution:

1. **Understanding Plastid Inheritance**:
- The first statement mentions that plastid inheritance in *Mirabilis jalapa* is a true example of cytoplasmic inheritance.
- **Analysis**: This statement is correct because plastids, which include chloroplasts, are inherited maternally (from the female gamete) and are indeed examples of cytoplasmic inheritance.

2. **Inheritance of Cytogenes**:
- The second statement claims that the inheritance of cytogenes occurs only through the female.
- **Analysis**: This statement is also correct. Cytogenes are genes located in the cytoplasm, and they are inherited from the mother, making this a case of maternal inheritance.

3. **Reciprocal Cross in Cytoplasmic Inheritance**:
- The third statement states that in cytoplasmic inheritance, reciprocal crosses can affect the result.
- **Analysis**: This statement is true. In cytoplasmic inheritance, the traits are often determined by the maternal parent, and reciprocal crosses can yield different results due to the maternal contribution.

4. **Cytoplasmic Inheritance and Chirogenes**:
- The fourth statement asserts that true cytoplasmic inheritance occurs due to chirogenes.
- **Analysis**: This statement is incorrect. Chirogenes are nuclear genes, not cytoplasmic genes. Cytoplasmic inheritance is due to cytogenes, which are inherited through the cytoplasm from the female parent.

### Conclusion:
The statement that is not correct is the fourth one: "True cytoplasmic inheritance occurs due to chirogenes."