毛菍传粉生物学研究

为探讨毛菍(Melastoma sanguineum Sims.)传粉生物学特性，对海南霸王岭国家级自然保护区林缘、林内和林隙3个生境内毛菍的花期、花部形态、访花昆虫等进行观察，同时对其繁育系统相关指标进行了测定。结果表明：毛菍无花蜜分泌；花瓣对访花昆虫有吸引作用；访花昆虫主要有蜂类、食蚜蝇类和丽金龟类；主要传粉昆虫有木蜂、熊蜂，其中木蜂传粉活动最为活跃，为最有效传粉昆虫。毛菍具典型的异型雄蕊，长、短雄蕊在传粉过程中具有明确的功能分化，推测这是毛菍保证传粉成功的策略。毛菍为自交亲和的异交种，需要昆虫传粉；人工自交和异交均具有较高的坐果率；不存在无融合生殖、主动自花授粉和滞后自交的生殖保障现象；其繁育系统是兼性自交。昼夜温差较小和相对湿度较高的林内和林隙生境有利于延长群体花期；光照充足、温度相对较高的林缘生境，花朵发育较快，柱头可授性的时间稍早。花粉、传粉者和环境条件是制约毛菍野外传粉效率的主要因素。

Studies on Pollination Biology of Melastoma sanguineum Sims (Melastomataceae)

In order to understand the pollination characteristics of Melastoma sanguineum Sims., the florescence, floral character, visiting insects of M. sanguineum grown in three habitats were observed in Bawangling National Nature Reserve, and the indexes related to breeding system were determined. There is no nectar secreted throughout the whole florescence. The petals play the role in attracting insect visitors. Apoidea, Syrphidae, Tutelidae and etc. are the main flower-visiting insects, while carpenter bees and bumble bees are the main pollinators, and carpenter bees are the most effective pollinators. The flowers have heteromorphic stamens, of which the long and short stamens have clear functional differentiation in the pollination process, suggesting that it is the pollination strategy of M. sanguineum. Melastoma sanguineum is a self-compatible out-crossing species. The fruit setting rates are significantly high in both artificially out-crossed and self-pollinated flowers. There is no reproductive security phenomenon, such as apomixis, active self-pollination and lag self-crossed, and pollinators are necessary for M. sanguineum. Its breeding system is typical facultative inbred type. The habitats with low temperature difference between day and night, and high relative humidity, such as in forest and forest gap, are better for prolong blooming period of population, while development of flowers in forest edge with sufficient sunlight and high temperature is fast and stigma receptivity is early. So, the pollen, pollinators and environment condition are main factors effecting pollination of M. sanguineum in the field.