Comparison of Pollination Ecology for Koelreuteria paniculata Laxm. between Yantai and Zhangye in China

Koelreuteria paniculata Laxm. shows great potential in ornamental and pharmaceutical fields. To figure out the characteristics of pollination ecology, we investigated the flower characteristics, pollen viability, stigma receptivity, pollen/ovule and breeding system of the K. Paniculata. In addition, we studied the flowering dynamics of the K. paniculata and the frequency and characteristics of activity of the pollinators to detect whether different habitats would influence the process of pollination. Our data show that the flower of K. paniculata is unisexual flower. The anthesis is 5 to 6 days and the stigma is three-split. Both the pollen viability and the stigma receptivity reached thepeak level on day 2 after blossom. The duration of the peak flowering stage in Yantai is longer than that in Zhangye. Therefore, the frequency of the activity of pollinators in Yantai is relatively higher than that in Zhangye. The breeding system of K. paniculata is mainly outcrossing and pollinators play an important role in the pollination.