夏蜡梅和光叶红蜡梅花发育特性和柱头可授性

对蜡梅科Calycanthaceae夏蜡梅属Sinocalycanthus夏蜡梅Sinocalycanthus chinensis和美国蜡梅属Calycanthus光叶红蜡梅Calycanthus floridusvar.oblongifolius的花发育进程进行了观察,同时利用活体花粉萌发法对其柱头可授性进行了检测。结果表明,夏蜡梅和光叶红蜡梅花发育进程均可以分为：紧蕾期、大蕾期、松蕾期、花开放而花药未裂和花开放花药开裂等5个时期,各个时期间隔1～2d,晴朗、高温天气将加速花的发育;雄蕊和退化雄蕊的发育进程从紧蕾期到花开放散粉阶段为直立到平展再到合拢状,这种花部动态变化特征有利于异交;两者的柱头可授期均为7～8d,到花开放而花药未裂阶段达到最强。光叶红蜡梅和夏蜡梅花发育特性基本相似,只有柱头的发育和花药的生长存在一定的差异。

Flower development and pistil receptivity in Sinocalycanthus chinensis and Calycanthus floridus var.oblongifolius

The flower development process and pistil receptivity of Sinocalycanthus chinensis and Calycanthus floridus var. oblongifolius were studied by macroscopic observation and using an in vivo pollen germination method. Flower development stages, consisting of a） small flower buds, b） large flower buds, c） relaxed flower buds, d） blooming but anther not dehisced, and e） blooming with anther dehisced, as well as pistil receptivity were almost consistent, whereas pistil development and anther growth differed slightly. Each stage interval was 1 - 2 d with higher temperatures accelerating development. From the small flower bud stage to blooming with anther dehisced, stamens and staminodes were erect, expanding, and then folding. Pistil receptivity period for these two species was 7 - 8 d, and receptivity was strongest at the blooming but anther not dehisced stage. This flower structure and its relative movement facilitated to outcrossing.