The Research On Pollination And Reproductive Strategy Of An Orchid Pleione Formosana

Pleione formosana is an endangered orchid species. Due to natural disasters and man-made interference, its survival and development are extremely distured. Therefore, the investigation of its distribution and survival status is needed to promote the conservation and exploration of Pleione formosana. In this paper, a field investigation and experimental observation of2successive years has been done to ascertain the resources distribution of Pleione formosana in Fujian province, its resource distribution, population characteristics, pollination mechanism, breeding system, and population reproductive strategies were revealed. The main research results are as the following:(1) Based on the field investigation,9new distribution sites have been found in Fujian province. They are in LingTongYan, MeiHuaShan, DaiYunShan, HeiYingTan, JiuXianShan, ShiNiuShan, BaiYunShan and FouZiYan.(2) Pleione formosana does not show self incompatibility or cross incompatibility. Since the flowers can not automatically fertilizate, pollinators are needed for pollination.(3) The pollinating insects of Pleione formosana are Bombioxylocopa chinensis and Bombus trifasciatus. The color of Pleione formosana is pink to pale purple, attracting insects to visiting flowers. While Pleione formosana almost has no nectar, its labellum is interspersed with yellow, red or brown markings which are almost like the nectar, attracting pollinators to entering labellum for pollination. The pollination mechanism of Pleione formosana is a typical food deception.(4) The effective pollination behaviors in Pleione formosana populations are few, and the natural seed setting rate of Pleione formosana is low, the RRS is between0.01-0.03.(5)The reproductive strategies of Pleione formosana:Under normal circumstances, the population’s reproduction mainly follows seed propagation mode. But it affected by the environment. Asexual reproduction method can give population new individuals, but its primary role is as the continuation of life to keep the number of individuals and make the population existing. Sexual reproduction and asexual reproduction are combined to adapt to the changes in the surrounding environment, to ensure the continuation and development of the population. Since the living requirement of Pleione formosana is harsh, which is also largely affected by environmental changes and the artificial picking, there is still a lot of uncertainties for the survival and development of the existing populations.