对濒危植物有效传粉昆虫种类及其传粉行为的主要影响因素进行研究是科学合理地制订保护措施,从而对该物种实施有效保护的一个前提条件。安徽羽叶报春Primula merrilliana为二年生草本,具二型花,是我国特有的珍稀濒危物种。本文对其有效传粉昆虫种类、传粉行为及花朵密度和种群大小对传粉效果的影响进行了研究。结果表明安徽羽叶报春的有效传粉昆虫为截形蜂虻Bombylius major和中华雏蜂虻Anastoechus chinensis,而不是先前认为的蓟马Thrips sp.。花朵密度和种群大小对传粉效果均有显著的影响。高密度的花朵可以提高对有效传粉昆虫的吸引力,传粉昆虫数/天、被访花朵数/天和平均每花的被访次数/天与样方花朵的密度呈正相关关系。柱头所接受的正配花粉数和总花粉数及正配花粉数所占的比例均随种群中植株数目的增加而增加。型比的偏离和传粉昆虫的缺乏可能是导致小种群中传粉不利的主要因素。
In order to make a scientific and practical plan for conservation of an endangered species, it is indispensable to identify the kind of insects effective in legitimate pollination and to clarify the main factors on their pollination behavior. Primula merrilliana, a small biennial rosette herb with distylous flowers, is an endangered and endemic species of China. In this study, the effective pollinators and the effects of flower density and popula- tion size on pollination efficiency were investigated. The results indicated that the primary effective pollinators of this distylous herb were two bee flies, Bombylius major and Anastoechus chinensis rather than Thrips sp., which was previously considered as an effective pollinator for the plant. The density of flowers and the population size were the two main factors that influenced pollination efficiency of P.merrilliana. Flowers with higher density attracted more pollinator visits, particularly in low dense populations. The number of pollinators and flowers visited per day and the average time of a flower visited per day were significantly positively correlated to the density of flowers in the samples. Legitimate pollination and its percentage of total stigmatic pollen loads were higher in larger populations. The biased ratio of short-styled and long-styled flowers and pollinator limitation might be responsible for pollination disadvantages in small populations.