摘要
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 selfing 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.
出处
《广西植物》
CAS
CSCD
北大核心
2011年第2期160-166,共7页
Guihaia
基金
国家重点基础研究发展计划(2007CB411600)~~
关键词
凤仙花科
传粉
繁育系统
雌雄异熟
柱头运动
雌雄干扰
Balsaminaceae
pollination
breeding system
dichogamy
stigma movement
male-female interference