吉祥草的花部器官发生及其系统学意义

利用扫描电镜（SEM）观察了吉祥草（Reineckia carnea）（铃兰科）的花部器官发生发育过程。吉祥草花被片、雄蕊的发生方式是由近轴端向远轴端发生的逆单向型（reversed unidirection）,花发育后期花被片合生形成花被筒,花丝与之贴生。伴随花被片、雄蕊发生,三枚心皮也由近轴向远轴方向相继发生,随后彼此合生发育。花序顶部的花易发生花器官数目变异。结合早期花原基形态以及花器官数目变异情况分析,吉祥草的花被片与雄蕊可能是由共同原基分化而成。从花部器官发生式样和花被筒形成时间两方面比较吉祥草属、白穗花属和铃兰属的特征发现,三属中,铃兰属处于相对进化的位置,而白穗花属比吉祥草属更为原始。

Floral Organogenesis of Reineckia carnea (Convallariaceae) and Its Systematic Significance

The floral organogenesis of Reineckia carnea （Convallariaceae） was observed under scanning electron microscope. The tepal and stamen primordia of R.carnea initiated in a reversed unidirection type. The tepals,partly fused with filaments,formed a short tube at the late stage. Carpel primordia initiated,which overlapped by tepal and stamen primordia,by the same pattern,then fused into a syncarpous gynoecium. The flowers on the tip of inflorescences were prone to vary in floral organ numbers. Considering the floral organogenesis traits of R.carnea in early stages and floral organ number variation,tepals and stamens should differentiate from common primordia. Characters of the floral organogenesis pattern and perianth tube formation time of Reineckia,Speirantha and Convallaria,revealed that Convallaria was more derived among them,and Speirantha was more primitive than Reineckia.