Regarding transgenic tobacco plants which is resistance to the nematode meloidegyne incognita, the correct statements are
A. The nematode parasite can't infect the transgenic host
B. The nematode parasite can't produce mRNA in host cells
C. The host cells contain the vector Agrobacterium
D. Host cells produce both sense and antisense RNA of a particular gene of the nematode

Options

A. A and C only
B. B and D only
C. D only
D. All of these

Answer

To determine the correct statements regarding transgenic tobacco plants resistant to the nematode Meloidogyne incognita, let's analyze each option step by step:

### Step 1: Understanding Transgenic Tobacco Plants
Transgenic tobacco plants have been genetically modified to express certain traits, in this case, resistance to the nematode Meloidogyne incognita. This is typically achieved by inserting a gene of interest into the plant's genome using a vector, often derived from the bacterium Agrobacterium tumefaciens.

### Step 2: Analyzing Each Statement
- **Statement A:** "The nematode parasite can't infect the transgenic host."
- **Analysis:** This statement is true. The purpose of creating a transgenic plant is to provide resistance against the nematode, meaning that the nematode should not be able to infect the plant.

- **Statement B:** "The nematode parasite can't produce mRNA in host cells."
- **Analysis:** This statement is also true. The transgenic plant produces both sense and antisense RNA that can interfere with the nematode's mRNA synthesis, preventing it from producing necessary proteins for its survival and reproduction.

- **Statement C:** "The host cells contain the vector Agrobacterium."
- **Analysis:** This statement is misleading. While Agrobacterium is used to introduce the gene into the plant cells, it is not present in the host cells after the transformation process. Therefore, this statement is false.

- **Statement D:** "Host cells produce both sense and antisense RNA of a particular gene of the nematode."
- **Analysis:** This statement is true. The transgenic tobacco plants are designed to produce both sense and antisense RNA, which can lead to RNA interference (RNAi) against the nematode's mRNA, effectively blocking its function.

### Conclusion
Based on the analysis:
- **Correct Statements:** A, B, and D are true.
- **Incorrect Statement:** C is false.

### Final Answer
The correct statements regarding transgenic tobacco plants resistant to Meloidogyne incognita are:
- A. The nematode parasite can't infect the transgenic host.
- B. The nematode parasite can't produce mRNA in host cells.
- D. Host cells produce both sense and antisense RNA of a particular gene of the nematode.