紫花地丁开放花与闭锁花的发育及可溶性糖与淀粉含量的研究

The Study on Dimorphic Flower Development and the Soluble Sugar and Starch Content in Viola philippica

紫花地丁(Viola philippica)为典型的两型花自花受精植物,具有开放花和闭锁花混合繁育系统。通过对开放花和闭锁花花芽形态发育的比较发现:开放花与闭锁花在花芽发育早期形态相似,4轮花器官原基均正常发生。出现明显差异的时期为4轮花器官原基形成以后,小孢子发育时期为产孢细胞阶段,开放花的5个花瓣与5枚雄蕊继续发育,每个雄蕊有4个花药室;而闭锁花只有2枚雄蕊继续发育,每个雄蕊有2个花药室,其余雄蕊与所有的花瓣依然为器官原基状态,不再发育。通过对花芽与叶片可溶性糖与淀粉含量的检测发现,花器官原基形成之后,开放花与闭锁花形态出现明显差异阶段开始,随着花芽的发育,可溶性糖与淀粉含量均呈上升趋势,且开放花花芽中的含量均明显高于对应发育阶段闭锁花花芽;而开放花植株的叶片可溶性糖与淀粉含量均低于闭锁花植株叶片,说明开放花所需要的能量高于闭锁花,推测可溶性糖与淀粉含量的差异与两型花发育有一定的关系。

Viola philippica is a typical dimorphic cleistogamous species with the chasmogamouscleistogamous mixed breeding system. No visible morphological difference were found between chasmogamous and cleistogamous flower development before 4 rounds floral organs primordium formation. The development stage of significant difference appeared at the stage of the sporogenous cell after floral organs primordium occurred. During late developmental stage of flower buds,5 petals and 5 stamens were all continue growing,and each anther had 4 locules in chasmogamous flower. But only 2 stamens continued development,other stamens and all petals still stayed the primordium state,and each anther had 2 locules in cleistogamous flower. The content of soluble sugars and starch in the floral buds was on the up trend with the development of flower in chasmogamous and cleistogamous plants from the second stage to the fifth stage. The content of either soluble sugars or starch in chasmogamous flowers was all higher than the cleistogamous flowers in corresponding development stage. But the content of soluble sugars and starch in the leaf of chasmogamous plants were less than the leaves of cleistogamous plants. The results showed that the investment of energy in chasmogamous flowers was higher than the cleistogamous flowers. We suspected there were some correlation between the content of soluble sugars and starch and the dimorphic flower development.