POLLINATION ECOLOGY OF DERRIS TRIFOLIATA LOUR. (FABACEAE)

摘要

Derris trifoliata is a deciduous woody climber. It is a hermaphroditic, self-compatible species with mixed breeding system. The flowers are specialized and exhibit explosive pollination mechanism which is adapted for tripping and subsequent pollination by insects. The short- and long-tongued bees trip the flowers and hence the plant is melittophilous. Autogamy is a mode of pollination but fruit set rate in this mode is negligible suggesting that its breeding system is essentially vector-dependent. Flower bud abortion rate is 29%. In this species,1-3 seeds are produced per pod although the ovary contains 6 ovules. The recorded natural fruit set rates, ovule abortion, fruit abortion and reduced seed set rate were considered to be related to the pollination rate, elimination of genetically inferior seeds prior to their maturation and to the availability of nutrient resources to the parent plant.