Melampy M N
Peace Corps and INDERENA Conservation Program, Bogota, Colombia.
Oecologia. 1987 Sep;73(2):293-300. doi: 10.1007/BF00377521.
In the eastern Andes of Colombia, the shrub Befaria resinosa (Ericaceae) has peaks of flowering that are separated by extended periods of low flower production. The effect that these fluctuations in flower production have on pollen flow was investigated by using fluorescent dye as a pollen analog. Dye applied to open flowers was dispersed over long distances more often during low flower production than during high flower production. Whether enhanced pollen dispersal during flowering lows is of benefit to individual plants is not clear. The proportion of flowers that set fruit is positively correlated with flower abundance, negating the possibility that increased pollen dispersal results in a higher rate of fruit production due to outbreeding effects. It is also difficult to attribute the pattern of fruit production to changes in pollinator visitation rates, which are negatively correlated with flower abundance in the case of hummingbirds and not correlated at all with flower abundance in the case of insects. An opportunistic, large-bodied hummingbird (Colibri coruscans) visits B. resinosa during high flowering and may be a particularly effective pollinator, accounting for some of the increase in the proportion of flowers setting fruit. Rainfall is positively correlated with flower production and may be an important factor in shaping flowering phenology, but it is not significantly correlated with the proportion of flowers setting fruits. The possibility that low-level flowering may counteract inbreeding that results from peak flowering is discussed.
在哥伦比亚安第斯山脉东部，灌木树脂贝法里亚（杜鹃花科）的开花高峰期之间间隔着长时间的低花量期。通过使用荧光染料作为花粉类似物，研究了这些花量波动对花粉传播的影响。在低花量期，涂抹在开放花朵上的染料比在高花量期更常被远距离传播。尚不清楚开花低谷期花粉传播增强是否对个体植物有益。结果实的花朵比例与花的丰度呈正相关，这排除了由于异交效应导致花粉传播增加从而使果实产量更高的可能性。也很难将果实产量模式归因于传粉者访花率的变化，对于蜂鸟而言，传粉者访花率与花的丰度呈负相关，而对于昆虫而言，传粉者访花率与花的丰度根本不相关。一种机会主义的大体型蜂鸟（闪耀蜂鸟）在高花期会拜访树脂贝法里亚，它可能是一种特别有效的传粉者，这解释了结果实的花朵比例增加的部分原因。降雨量与花的产量呈正相关，可能是塑造开花物候的一个重要因素，但它与结果实的花朵比例没有显著相关性。文中讨论了低水平开花可能抵消高峰期开花导致的近亲繁殖的可能性。
