Pollination Ecology of Caesalpinia crista （Leguminosae： Caesalpinioideae）

The flowering phenology, pollination ecology and breeding system of Caesa/pinia crista L.were studied in Dinghushan Nature Reserve, Guangdong, China. The species started blooming in Februaryor March, then last till late April. It took about one week from first flower appearance to its full blooming,which lasted for 2-4 d. The pollen-ovule ratio was 18 000~500. The breeding system was self-incompatible,and protogynous xenogamy. Hymenoptera constituted the major group of pollinators. The pollination typeis ambophily, the species could be pollinated by wind if the pollinators were unavailable: this is the firstrecord of ambophily in the genus Caesalpinia. The floral structure adaptation to the pollinating behavior ofcarpenter bees was described. The influences of artificial treatments in pollination biological studies onthe flowering and fruiting of the plants were also discussed.