FLORAL BIOLOGY, HUMMINGBIRD POLLINATION AND FRUIT PRODUCTION OF TRUMPET CREEPER (CAMPSIS RADICANS, BIGNONIACEAE)

摘要: Trumpet creeper is self-incompatible and bears long, tubular, orange flowers from June to September. Flowering peaks rapidly, then declines continues at low levels for several weeks. The initial burst of flowering may attract pollinators that return even during subsequent reduced flowering. Most open before noon nectar production totals 110 ,l 26% sucrose equivalents per flower, an exceptionally high a temperate zone plant. Production ceases within 20-30 hr flower opening, but corollas persist days serve pollinators. Effective pollination reduces the period stigma receptivity speeds closing lobes. Only 1-9Wo produced mature fruits four sites in Illinois Missouri. Roughly 400 pollen grains had be deposited on receptive cause fruit development beyond abortion. At two sites, 17% 89% stigmas received over grains. Assuming 50% were same plant, one site was clearly pollinator limited, second have been. Ruby-throated Hummingbirds (Archilochus colubris) ten times as much visit honeybees (Apis mellifera) bumblebees (Bombus spp.). Fruit set highest where rubythroat visitation most frequent. appears primarily adapted hummingbird pollination, can also adequately pollinated by bumblebees. This first attempts relate pollen-depositing capabilities any plant requirements production. Several characteristics suggest trumpet densities (often called traplining) its presumed original, woodland, habitat.