大白菜种子胎萌性状发生动态及其遗传初探

Preliminary Studies on Occurrence Time,Position and Inheritance Genetics of Seed Vivipary in Chinese Cabbage(Brassica rapa)

以高胎萌材料‘8407’、中度胎萌材料‘夏胜’和弱胎萌材料‘B热’,以及不发生种子胎萌的材料‘92S24’和‘72M’为试材,采用蕾期授粉、花期标记、定期采样方法,统计种子胎萌的发生状况,研究了大白菜种子胎萌现象的发生状况及其遗传规律。结果表明：‘8407’种子胎萌出现于花后14d,而‘夏胜’出现于花后23d,且前者的种子胎萌率极显著高于后者,二者的种子胎萌主要发生于花后26~32d的发育阶段。‘8407’的主枝种子胎萌率高于一次分枝和二次分枝,且主枝角果基部的种子胎萌率显著高于角果中部和顶部;‘夏胜’种子胎萌部位性不明显。根据杂交当代种子胎萌表现的差异,表明无胎萌对胎萌为显性,且胎萌特性同时受到细胞质和细胞核基因的共同调控。

High,middle and low vivipary-susceptible materials of‘8407＇,‘Xiasheng＇,‘B Re＇,and seed vivipary-tolerence of‘92S24＇and ‘72M＇were taken as test materials.By flower bud pollinating,flower labelling and regular interval sampling,the ratio of seed vivipary in Chinese cabbage lines was investigated.The seed vivipary occurrence time,position in the plant and inheritance genetics were studied in the Chinese cabbage.The results showed that,the vivipary of‘8407＇and‘Xiasheng＇occurred at 14 days and 23 days after flowering,respectively,and the former had a higher vivipary ratio than the latter and the main seed viviapry happened from 26 days to 32 days after flowering for both lines.The ratio of main branch was higher than first and second branch in‘8407＇,and the basic seeds in its pods had higher viviparysusceptible character than the seeds in middle and top of pods;whereas no difference in‘Xiasheng＇.By analyzing the ratio of seed vivipary in parent lines and their F1 hybrid,the results showed that no vivipary was dominant to vivipary,and the vivipary in Chinese cabbage was controlled by cytoplast and nucleus genes at the same time.