大豆品种自贡冬豆花芽分化及开花逆转过程的形态解剖学研究

研究了光周期反应敏感的晚熟大豆Glycine max (L.) Merr.]品种自贡冬豆在正常花芽分化和开花逆转过程中的解剖学特征。光周期处理包括连续短日照（SD, 12 h）、连续长日照（LD, 16 h）和13 d短日后转入长日(SD13d-LD)3种。结果表明, 自贡冬豆在连续短日条件下可正常开花结实；经13 d短日照处理后移至长日照下约50％的植株发生开花逆转，另外50％的植株形成短的顶端花序；在连续长日照下保持营养生长。短日照不仅促进大豆的生殖发育, 而且加快出叶速度。短日处理3 d基部叶腋开始分化花芽；13 d顶端分生组织开始分化花序，19 d顶端花序分化结束，29 d植株开花。SD13-LD处理，在移至长日照的最初14 d内，顶端分生组织继续分化花原基，但分化速度比连续短日处理慢，分化出的花芽数目少。长日处理20 d（出苗后33 d）左右，约50％植株的顶端分生组织逆转到营养器官的分化。在连续长日条件下，顶端分生组织一直分化叶片。还讨论了叶片和花器官的同源性。

Morphology and Anatomy of the Differentiation of Flower Buds and the Process of Flowering Reversion in Soybean cv. Zigongdongdou

he morphological and anatomical changes during floral development and flowering reversion of Zigongdongdou,a late-maturing and photoperiod-sensitive soybean cultivar,were investigated to identify anatomic characteristics of floral development in soybean.The following photoperiod treatments were conducted to obtain different developmental status and morphological changes:(1) Continuous short days(SD,12 h);(2) Continuous long days(LD,16 h);and(3) SD for 13 days and then LD(SD13d-LD).The results showed that Zigongdongdou plants normally bloomed and podded in continuous SD.About 50% of plants in SD13d-LD treatment reversed from reproductive development to vegetative growth,and other plants in this treatment bore short terminal racemes.In continuous LD,all plants kept vegetative status.SD not only promoted reproductive development of soybean plants but increased the appearing rate of leaves as well.In SD treatment,the first floral primordia were found in basal axil of plants at Day 3,and the apical meristem began to initiate raceme at Day 13.At Day 19,the terminal flower primordia were first found in apex.At Day 29,plants began to bloom.Plants in the treatment of SD13d-LD kept initiating floral primordia within the first fourteen days after transferred from SD to LD, but the initiating rate was slower and the number of floral primordia was fewer than that in continuous SD.About half of plants reversed to initiate vegetative organs after transferring to LD for 20 days(33 days after emergence).While in continuous LD,the apical meristem only produced leaves.The homology of leaves and floral organs was also discussed in this paper.