大豆杂交中伪杂种产生的原因分析

Analysis on Reasons for False Hybrid Seeds of Soybean

有性杂交是目前大豆育种的主要途径,但大豆存在花器小,人工去雄授粉易伤柱头,伪杂种率高,杂交成活率低等不利因素。为了改进大豆杂交相关工作环节,提高杂交效率,采用整体去雄技术在大豆盛花期早晨的不同时间段去雄及早晨与下午去雄后用新鲜叶片包扎与不包扎处理,在不进行人工授粉前提下,根据结荚情况来分析伪杂种产生的主要原因。结果表明:在不同时间及不同包扎处理情况下,大豆去雄后不授粉均存在伪杂交现象,但去雄后包扎处理伪杂交较低;早晨去雄不授粉的时间越早伪杂交越低;不管包扎与否,下午去雄均比早晨去雄伪杂交低;去雄不授粉包扎处理时,不管下午还是早晨去雄,包扎均比不包扎伪杂交低。因此,黄淮海区域大豆早晨用整体去雄技术进行有性杂交是可行的,但去雄时间应在6∶30之前,并要以下午去雄为主,去雄后最好用新鲜叶片包扎处理。

Sexual hybridization is the main way in soybean breeding.However,there are several unfavorable factors during soybean crossing.For example,small flower organs,stigmas are easily broken during emasculation,high false hybrid rate and low hybrid survival rate.In order to improve the crossing procedure and increase the crossing efficiency,we analyzed the false hybrid rates after totally emasculating but not pollinating soybean flowers at different times in the blooming mornings,or after totally emasculating but not pollinating soybean flowers with or without wrapping leaves in the morning and afternoon.The results showed that false hybridization could always happen after emasculating but not pollinating soybean flowers at different emasculating times with or without leaf-wrapped treatments.Leaf-wrapped treatment resulted in a lower false hybrid rate after emasculation.The false hybrid rate was lower after the emasculation in the afternoon than in the morning.We emasculated soybean flowers earlier in the morning;the false hybrid rate was lower.Therefore,in the Huanghuaihai region,it is feasible to do hybridization in the morning,but the total emasculation in the morning should be finished before 6∶30.However,it is better to emasculate soybean flowers in the afternoon and wrap emasculated flowers with leaves.