A plant species A has a diploid number of chromosomes as 12. Another plant species B has a diploid chromosome number off 16. The allopolyploid developed. By hybridization of A and B shall have a diploid chromosome number as

Options

A. 14
B. 28
C. 40
D. 58

Answer

To solve the problem of determining the diploid chromosome number of the allopolyploid developed from the hybridization of two plant species A and B, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Diploid Numbers**:
- For plant species A, the diploid number (2N) is given as 12.
- For plant species B, the diploid number (2N) is given as 16.

2. **Determine the Haploid Numbers**:
- The haploid number (N) is half of the diploid number.
- For species A:
\[ N_A = \frac{2N_A}{2} = \frac{12}{2} = 6 \]
- For species B:
\[ N_B = \frac{2N_B}{2} = \frac{16}{2} = 8 \]

3. **Combine the Haploid Numbers**:
- In allopolyploidy, the haploid sets from both species combine.
- Therefore, the total haploid number in the hybrid will be:
\[ N_{hybrid} = N_A + N_B = 6 + 8 = 14 \]

4. **Calculate the Diploid Number of the Hybrid**:
- Since the diploid number is twice the haploid number, we calculate:
\[ 2N_{hybrid} = 2 \times N_{hybrid} = 2 \times 14 = 28 \]

5. **Final Answer**:
- The diploid chromosome number of the allopolyploid developed from the hybridization of species A and B is 28.

### Summary:
The diploid chromosome number of the allopolyploid developed from the hybridization of species A (12) and species B (16) is **28**.

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