The use of synthetic varieties is more beneficial than single-cross or double-cross hybrids. The reasons are-
A. Yield of synthetic varieties is higher than hybrids
B. Farmers can save their own produce as seeds and no need to buy new seeds every year
C. Synthetic varieties have wider adaptability than hybrids
D. No need to make fresh crosses every year to produce seeds
Choose the correct answer from the options given below:
A. Yield of synthetic varieties is higher than hybrids
B. Farmers can save their own produce as seeds and no need to buy new seeds every year
C. Synthetic varieties have wider adaptability than hybrids
D. No need to make fresh crosses every year to produce seeds
Choose the correct answer from the options given below:
Show Hint
- A, B and D only
- B, C, and D only
- A, C, and D only
- A, B, and C only
The Correct Option is B
Solution and Explanation
A synthetic variety is developed by intercrossing a set of inbred lines or clones that have been evaluated for general combining ability (GCA). Once developed, the variety is maintained by open pollination.
Step 2: Detailed Explanation:
Let us analyze each of the reasons provided:
- Statement A: Hybrids utilize maximum heterosis (specific combining ability), whereas synthetic varieties rely on general combining ability and exhibit lower heterosis. Thus, the yield of synthetic varieties is generally lower than that of single-cross or double-cross hybrids. Statement A is incorrect.
- Statement B: Because synthetic varieties are genetically heterogeneous, inbreeding depression in subsequent generations is minimal. Farmers can save seed from their harvest to replant for several generations without a severe drop in yield, unlike hybrids where new seeds must be purchased annually. Statement B is correct.
- Statement C: Synthetic varieties consist of a diverse mixture of genotypes, providing them with a buffered genetic base. This gives them wider adaptability across different environments and seasons compared to genetically uniform hybrids. Statement C is correct.
- Statement D: Synthetic varieties are maintained via open pollination in isolation. There is no need to perform controlled crosses every year to produce seed, making seed production simple and inexpensive. Statement D is correct.
Thus, statements B, C, and D are the correct reasons.
Step 3: Final Answer:
Hence, the correct answer is B, C, and D only.
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Choose the correct answer from the options given below:
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