ABSTRACT

Most flowering plants are visited by various pollinator insects. To understand floral specialization for pollinators, the relative importance of different flower visitors to the focal plant species should be revealed. In the present study, we observed the insects that visited the orchid Platanthera hologlottis throughout the day and night using interval timer photography to reveal the relative importance of diurnal and nocturnal flower visitors. We observed visitation by both diurnal (e.g. the butterfly Ochlodes ochraceus) and nocturnal (e.g. the moth Thysanoplusia intermixta) insects and examined their relative contribution to fruit production and pollinarium removal experimentally. Results showed that the fitness was higher in flowers visited by nocturnal insects than in those visited by diurnal insects. These results suggest that the floral traits of P. hologlottis may be specialized for nocturnal flower visitors rather than diurnal flower visitors.

摘要

大多数开花植物都受到各种传粉昆虫的访问。为了了解授粉媒介的花卉专长，应该揭示出不同的花卉访客对重点植物物种的相对重要性。在本研究中，我们使用间隔定时摄影观察了白天和黑夜全天访问兰花Platanthera hologlottis的昆虫，以揭示昼夜访客的相对重要性。我们观察到白天（例如蝴蝶Ochlodes ochraceus）和夜间（例如蛾Thysanoplusia intermixta）的访问）昆虫，并通过实验检查了它们对水果生产和去除花粉的相对贡献。结果表明，夜间昆虫访问的花朵的健康度高于昼夜昆虫访问的花朵。这些结果表明，P。hologlottis的花性状可能专门针对夜间花客，而不是昼夜花客。