茶皂素、生石灰等防治稻田福寿螺的效果评估

福寿螺已成为我国南方局部稻区严重危害水稻的有害生物,为解决常用的化学杀螺剂污染环境和农产品的问题,分别在室内和大田环境下研究了生石灰、碳酸氢铵、茶麸和茶皂素4种替代物质防治福寿螺的效果。茶皂素、茶麸和生石灰对稻田福寿螺有很好的防治作用。在室内试验中40 mg/L和50 mg/L茶皂素处理在48 h 即达到了100%的防效;在大田试验中茶皂素6.0 g/m²的处理在第4天、1.5 g/m²的处理在第16天均达到了100%的防治效果,且速效性和持效性也显著优于其它物质。30 g/m²和45 g/m²的茶麸处理以及45 g/m²的生石灰处理在大田试验第16天的防治效果也在80%以上。这3种物质对稻田稗草还有很好的抑制作用。碳酸氢铵对福寿螺防治效果较差,且能促进稻田稗草的发生。研究结果表明,茶皂素、茶麸和生石灰可作为化学杀螺剂的替代物质在大田中推广应用。

Evaluation of the controlling Pomacea canaliculata with calcium oxide, ammonium bicarbonate, Camellia oleifera powder and tea saponin

Pomacea canaliculata (Lamarck) is one of the most serious pests to the rice production area in southern China. In order to solve the problem caused by synthetic chemical molluscicides which are extremely toxic to the environment and agricultural products, we studied the efficiency of controlling P.canaliculata with four kinds of substitutes, calcium oxide, ammonium bicarbonate, Camellia oleifera powder and tea saponin, in laboratory and plot. The results indicated that the better control efficiency achieved using tea saponin, C.oleifera powder and calcium oxide. The mortality of snails achieved to 100% when the concentration of tea saponin was 40 mg/L and 50 mg/L, and treated for 48 h in laboratory. In the plot, mortality of snails were 100% using tea saponin at 6.0 g/m² with 4 days or 1.5 g/m² lasted 16 days. The quick-acting and lasting effect were better than those of other substitutes. Control efficiencies of C.oleifera powder at 30 g/m² and 45 g/m² and calcium oxide treatment at 45 g/m² are over 80% after 15 days. In addition, these three kinds of substitutes can control the Echinochloa crusgalli (L.) Beauv effectively in the rice paddy. Ammonium bicarbonate was less effective on controlling P.canaliculata, and can promote the occurrence of E.crusgalli. We concluded that tea saponin, C.oleifera powder and calcium oxide can be used as the substitutes of synthetic chemical molluscicides for contro- lling P.canaliculata in the rice paddy.