[Molluscicidal effect of suspension concentrate of metaldehyde and niclosamide in fields of mountainous areas in Yunnan Province].

ABSTRACT

OBJECTIVE: To evaluate the molluscicidal effect of 26% suspension concentrate of metaldehyde and niclosamide (MNSC) in the fields of mountainous areas in Yunnan Province. METHODS: Some representative Oncomelania snail environments of schistosomiasis endemic regions were selected as study areas in Heqing County, Yunnan Province and 26% MNSC and 50% wettable powder of niclosamide ethanolamine salt (WPN) were used to kill the snails with the mechanical spraying and sprinkler spraying methods respectively. RESULTS: Seven, 15, 30 days after the spraying with the mechanical spraying method, in corn fields, the snail mortality rates were from 88.68% to 92.88% in the MNSC group, and from 89.86% to 90.32% in the WPN group respectively, and in the ditch, the snail mortality rates were from 89.97% to 94.46% in the MNSC group and from 90.08% to 96.74% in the WPN group respectively, and there was no significant difference between the 2 groups (P > 0.05); 7, 15, 30 days after the spraying with the sprinkler spraying method, in corn fields, the snail mortality rates were from 66.14% to 89.11% in the MNSC group, and from 78.40% to 91.22% in the WPN group, respectively, in the ditch, the snail mortality rates were from 84.13% to 94.27% in the MNSC group, and from 85.81% to 95.26% in the WPN group respectively, and there was no significant difference between the 2 groups (P > 0.05). CONCLUSION: 26% MNSC has good molluscicidal effect in the fields of mountainous areas in Yunnan Province