Abstract:

Pomacea canaliculata（golden apple snail）is a major pest of aquatic crops. It has high fecundity and disperses rapidly with water flow. Current control measures rely primarily on chemical molluscicides，which to some extent affect water quality in paddy fields and the safety of other aquatic organisms. Therefore，there is an urgent need to develop efficient and environmentally friendly “green” control strategies against this pest. In this study，we compared the effects of different fertilizer treatments， namely，ammonium bicarbonate applied as base fertilizer，ammonium bicarbonate applied as base fertilizer plus one topdressing， tea seed cake，and tobacco stem organic fertilizer， on snail mortality as well as on rice yield and agronomic traits in paddy fields in Huangyan District，Taizhou City. The results showed that all the tested fertilizer treatments exhibited certain molluscicidal effects. Among them，tea seed cake applied at 300 kg·hm^-2 achieved the highest snail mortality rate of 43.38%. In terms of rice yield，all the tested treatments resulted in higher grain yields compared with the conventional fertilizer control. The highest yield was observed under the tea seed cake treatment at 375 kg·hm^-2，with an increase of 1 521.20 kg·hm^-2（20.37%）over the control，followed by tobacco stem organic fertilizer at 300 kg·hm^-2，which gave a yield increase of 19.83%. Under different application rates of tea seed cake，both the effective panicle number and 1 000-grain weight remained at relatively high levels. The treatment of ammonium bicarbonate as basal fertilizer at 375 kg·hm^-2 showed the highest net benefit increase of 3 345.29 yuan·hm^-2，whereas the three application amounts of ammonium bicarbonate as one basal plus one topdressing all exhibited lower benefit increases than the other fertilizer treatments. Collectively，these findings indicate that the tested fertilizer treatments have promising potential in controlling P. canaliculata while simultaneously improving rice yield and economic returns，thus providing a valuable reference for the green management of this snail in aquatic crop fields.

Key words: fertilizer, Pomacea canaliculata, molluscicidal effects, rice（Oryza sativa）, agronomic trait, yield