通过对峨眉山特有种侧穗凤仙花的开花生物学特性、花器官结构、传粉者种类和访花行为、繁育系统、花粉胚珠比(P/O)及花粉活力的研究.发现居群之间花的寿命变化比较大,它们的雄蕊期长,雌/雄蕊期比为0.12～0.17;花粉胚珠比达到4.6万,花粉在开花第一天有很高的活力(＞90%);传粉者为熊蜂和天蛾,熊蜂包括贞洁熊蜂、白背熊蜂;存在盗蜜者灰熊蜂.侧穗凤仙花是自交亲和的异交植物,能通过雌雄异熟和独特的花部结构来避免自交及雌雄干扰.侧穗凤仙花存在柱头运动现象,并通过柱头运动增强了雌性功能.由于昆虫访花频率很低,侧穗凤仙花自然结果率(26%)很低,人工授粉明显增加了结果率(42%),说明侧穗凤仙花的低结果率可能和传粉者限制有关.%Pollination ecology and the breeding system of Impatiens lateristachys, a species endemic to the Emei Mountain were studied. The floral phenology,floral structure,pollen-ovule ratio(P/O),pollen viability,floral visitors and their behavior,and the breeding system were observed and determined. The flowering phase of the protandrous I. lateristachys lasted for a long time. The life span of an individual changed between the populations, but the female phase-male phase ratio was similar(0. 12-0. 17). The pollen/ovule ratio was 460 thousand,and pollen viability (MTT test)was at high level on the first day(>90 ％). The primary pollinators were Bombus festivus Smith and B.parthenius Richards;secondary pollinators were hawk moth;and B. grahami Frison was nectar gatherer. I lateristachys was a self-compatible species,its special floral structure and protandrous character could avoid selling and intrafloral male-female interference very well. The stigma movement of I. lateristachys was responsible for enhancing the function of the female. Fruit set was relatively low(26 ％ )under natural conditions, but hand-pollination increased the fruit set(42 ％). And the pollinator visitation rate(0. 2-2. 0)was significantly lower than that of other congeneric species(7. 1-8. 9),indicating that the fruit set may be limited by the shortage of pollinators.
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