小桐子花的性别与开花时间的相互关系

The Correlation between Flowering Sequence and Floral Gender in the Inflorescence of Jatropha curcas L. (Euphorbiaceae)

摘要:

通过对小桐子(Jatropha curcas L.)花序上小花的开花顺序和小花性别的观察，发现其聚伞花序中心花的性别与其开花时间相关联，同时还和周围其它小花的性别有很大的相关性。中心花若是在整个花序开花的第一天开放，仅有23.2%的可能是雌花；若在第二天及以后开放，有85%以上的可能为雌花。而中心花的性别又与其它花的性别相关，中心花如为雌花，那么聚伞花序上的其它小花有80%的可能性为雌花；但中心花若为雄花，那么整个聚伞花序上将不会再有雌花。研究小桐子的开花行为及性别控制规律，对于进一步人工调控小桐子花的性别表达，提高小桐子的产量、培育高产稳产品种，具有重要的应用价值。

Abstract:

Through the observation of the flowering sequences and gender of the inflorescence of Jatropha curcas L., the result shows that gender of apical flower has close correlation to flowering time, and also with the gender of other flowers on the same inflorescence. If the apical flower opened on the first day, the possibility of being female flowers is only 23.2%. But if the apical flower opened after the second day, the possibility would be over 85%. Meanwhile, if the apical flower was female, the possibility of inflorescences having other female flowers is 80%. But if the apical flower was male, the inflorescence will have no more female flowers. Understanding of flowering behavior and sex determination mechanism of Jatropha curcus is vital for manigulating gender expression, productivity improving, and breeding of new high productivity variety.