目的 观察新型灭螺药10%氯代水杨胺可湿性粉剂(LDS)对浙江省山丘地区钉螺和有螺环境的灭螺效果,为现场推广应用提供科学依据。方法 采用浓度0.1、0.2、0.4、0.6、0.8 mg/L的LDS分别进行实验室和现场浸杀法灭螺,采用浓度0.2、0.4、0.6、0.8、1.0 g/m2的LDS分别进行实验室喷洒法、现场喷洒法和撒粉法灭螺,同时设50%氯硝柳胺乙醇胺盐可湿性粉剂(WPN)药物对照和清水对照,观察药物的灭螺效果。结果 室内和现场浸杀试验LDS 0.1 mg/L浓度组,浸杀1 d钉螺死亡率分别达100%和95%以上,与WPN药物对照组相比差异无统计学意义(P＞0.05);室内喷洒灭螺LDS 0.8 g/m2浓度组,喷洒1 d钉螺死亡率＞95%,现场喷洒灭螺LDS 0.2 g/m2浓度组,喷洒3 d钉螺死亡率＞85%,现场撒粉灭螺LDS 0.4 g/m2浓度组,撒粉后1 d钉螺死亡率＞85%。各LDS试验组钉螺死亡率随着药物浓度的升高和作用时间的延长而升高。结论10% LDS对浙江省山丘地区钉螺和有螺环境具有较好的灭螺效果。

Objective To observe the molluscicidal effect of a novel molluscicide, 10% wettable powder of quinoid-2′,5-dichloro-4′-nitrosalicylanilide (LDS), on Oncomelania hupensis from the mountainous areas in Zhejiang province, China in the laboratory and field and to provide a scientific basis for the application of LDS in the field. Methods O. hupensis was immersed in 0.1, 0.2, 0.4, 0.6, or 0.8 mg/L LDS in the laboratory and field; 0.2, 0.4, 0.6, 0.8, or 1.0 g/m2 LDS was sprayed onto O. hupensis in the laboratory and field, or powder form of LDS was scattered onto O. hupensis in the field. Meanwhile, 50% wettable powder of niclosamide ethanolamine salt (WPN) and clean water were used as controls. The molluscicidal effects were evaluated. Results O. hupensis had mortality rates of 100% and over 95% after being immersed in 0.1 mg/L LDS for one day in the laboratory and field, respectively, with no significant differences compared without O. hupensis treated with WPN (P＞0.05). O. hupensis had a mortality of over 95% after being sprayed with 0.8 g/m2 LDS for one day in the laboratory, a mortality of over 85% after being sprayed with 0.2 g/m2 LDS for three days in the field, and a mortality of over 85% after being scattered with 0.4 g/m2 LDS powder for one day in the field. The mortality of O. hupensis increased as the concentration of LDS rose and the exposure to LDS was prolonged. Conclusion LDS (10%) has a good molluscicidal effect on O. hupensis from mountainous areas of Zhejiang province in the laboratory and field.