Abstract: Effect of the extracts from Sapium sebiferum and Pterocarya stenoptera leaves on physiological and biochemical functions of Oncomelania hupensis is studied under natural conditions.The results show that in comparing with beach ecosystem, the glycogen and total protein contents in O.hupensis from P.stenoptera and S.seoprum ecosystems are respectively decreased by 36.3 and 55.7%,27.5 and 54.5%.Specific activities of glutamic-oxalacetic transaminase (GOT) and glutamicpyruvic transaminase(GPT) are increased by 2.7 and 2.6 times, and their mortalities by 62 and 41%,respectively.The relationship between structures and functions of compounds for inhibiting O.hupensis reproduction isdiscussed in this paper.

Key words: Oncomelania hupensis, Pterocarya stenoptera, Sapium sebiferum, Chemical composition, greenhouse, yield, cucumber, nitrogen fertilizer, quality