珍稀濒危物种格木传粉方式和交配系统的初步研究

Preliminary Studies on Pollination and Mating System of Rare and Endangered Plant Erythrophleum fordii Oliv.

摘要:

为研究格木(Erythrophleum fordii Oliv.)的传粉方式和交配系统,在鼎湖山国家级自然保护区对珍稀濒危树种格木进行野外观察, 花的微器官(花粉和柱头)用扫描电镜观察,并进行控制授粉实验和遗传分析。结果表明,格木具有颜色亮丽和散发香味的总状花序,格木花粉包被厚重的粘性物质,柱头没有易于捕获花粉的结构,风媒传粉没有坐果,推断格木应该是通过虫媒传播花粉,或者主要是通过虫媒传播。遗传分析和在不同繁殖环境的两棵目标树的坐果情况表明,格木偶尔可以自交产生后代,但异交占据着绝对的优势,鼎湖山格木种群的异交率达到90.6%。格木传粉方式和交配系统的研究有利于对格木进行保护和保育。

关键词:格木;传粉方式;交配系统;遗传分析

Abstract:

Although a few efforts have been taken to conserve rare and endangered species Erythropleum fordii Olive., information about its pollination and mating system still remains unknown. The pollination and mating system of E. fordii through performing the field observation, SEM observation of pollen and stigma, controlled pollination experiment and genetic analyses in Dinghushan Nature Reserve, China were studied. Erythrophleum fordii has brightly colorful inflorescences and sends forth delicate odor, its pollen is coated by strong mucous substance and its stigmas have not specific structure for pollen capturing, and meanwhile the inflorescences pollinated by wind did not fruit at all, therefore it was inferred that E. fordii might be entomophilous. According to genetic analyses and fruiting of two object trees under contrasting reproductive situations, E. fordii can be selfing occasionally but out-crossing is dominant with out-crossing rate in the Dinghushan E. fordii community for 90.6%. This preliminary elucidation of pollination and mating system would benefit the conservation of E. fordii.

Key words:Erythrophleum fordii;Pollination;Mating system;Genetic analysis