Effects of temperature, and age of siliques, on hybrid embryo yield from interspecific crosses between Brassica napus and B. oleracea var. alboglabra

摘要

Reciprocal crosses were made between Brassica napus (AACC) and B. oleracea var. alboglabra (CC) with the objective of broadening genetic diversity in B. napus. An ovule culture technique was applied to obtain interspecific hybrid plants, and the efficiency of this technique was investigated between 6 and 16 days after pollination (DAP) under two temperature conditions,20/15°C and 15/10°C (dayight). Due to interspecific crossability barriers, a low total number of interspecific hybrid embryos/plants were obtained. Data were therefore pooled across plants and a chi-square test applied for statistical analysis.Response to temperature differed depending on which species was the female parent. Using B. oleracea var. alboglabra as the female parent, a significantly greater number of hybrid embryos were obtained from plants grown at 20/15°C, and between 12-16 DAP. With B. napus as the female parent, hybrid embryo numbers were greatest at 15/10°C, and 14-16 DAP. Thus, for this particular cross, the rate of interspecific hybrid production depends greatly on the interaction between the female parent and the growing temperature. The slower growing parent, B. oleracea var. alboglabra, was more productive in generating interspecific hybrids under higher temperatures.