Male Sterility in Inbred Lines for Hybrid Seed Production

Question:

Why is the cytoplasm being sterile important for male sterility in the male-fertile inbred lines used to produce hybrid F1 seed?

Answer:

The cytoplasm being sterile is necessary for male sterility in the inbred lines used to produce hybrid F1 seed. The male-sterile trait is incorporated into inbred lines to produce hybrid F1 seed on a commercial scale. The cytoplasm plays a crucial role in determining whether a plant is male-fertile or male-sterile in the context of inbred lines used for hybrid seed production. Male sterility is a desirable trait in these inbred lines as it facilitates the production of hybrid F1 seed.

Male sterility in inbred lines is a common strategy used in agriculture to produce hybrid seeds on a large scale. In the case of onions, male sterility is controlled by the interaction of a chromosomal allele pair hh and "sterile" (S) cytoplasm. When this combination is present, plants exhibit male sterility, which is desired for hybrid seed production.

If the cytoplasm is fertile instead of sterile in the male-fertile inbred lines, it would result in male-fertile plants. This would be unfavorable for hybrid seed production because fertile pollen production could lead to self-fertilization within the inbred lines, reducing the yield of hybrid F1 seed.

Therefore, the presence of the "sterile" cytoplasm is crucial for maintaining male sterility in the inbred lines and ensuring the successful production of hybrid F1 seed. By incorporating the male-sterile trait into inbred lines with sterile cytoplasm, breeders can produce hybrid seeds efficiently and effectively.

In conclusion, the cytoplasm being sterile is important for male sterility in the male-fertile inbred lines used for hybrid seed production to maximize the yield of hybrid F1 seed.