Effect of related physical factors on niclosamide molluscicide

Objective To find the effect of related physical factors on niclosamide molluscicide by experiment and to guide the practical work.Methods Molluscicidal experiments of niclosamide powder and 1% niclosamide solution were done respectively in laboratory after being insolated in sunshine for 6,12,24,48 and 72 h.Niclosamide without insolation was control group.SPSS11.0 software was used for analysis.LC50 of each groups in different time were counted.Results The insolation time was longer,the lower molluscicidal effects and higher LC50 values were observed in both experimental groups.At 0.125 mg/L concentration,there were statistically significant differences on the snail death rates between powder group and control in 48 h and 72 h,as well as that between 1% solution group and control group in 24,48 and 72 h.All P values were 0.044.Conclusion Sunshine affects molluscicidal effect of niclosamide obviously.In order to increase molluscicidal effect,the drug must contact snail sufficiently and early in the practical operation.