[Molluscicidal effect comparison between TDS and MNSC in field].

Area of Science:

• Agricultural Science
• Environmental Science
• Ecology

Background:

• Schistosomiasis japonica control relies on eliminating snail intermediate hosts.
• Chemical molluscicides like metaldehyde and niclosamide (MNSC) are widely used.
• There is a need for effective and potentially safer molluscicidal alternatives.

Purpose of the Study:

• To evaluate the molluscicidal efficacy of a plant-derived molluscicide, "Luo-wei" (TDS), in a natural environment.
• To compare the field performance of TDS against a standard chemical molluscicide, MNSC.
• To assess the stability and effectiveness of TDS under different application methods.

Main Methods:

• Field study conducted in an ecological area inhabited by Oncomelania hupensis snails.
• Application methods included immersion (2.5 g/m³ for TDS, 2 ml/m³ for MNSC) and spraying (3 g/m² for TDS, 2 ml/m² for MNSC).
• Synchronous design and parallel comparative methods were employed to assess molluscicidal effects.

Main Results:

• TDS achieved a 90.70% snail mortality via immersion and 81.40% after 7 days of spraying.
• MNSC achieved 99.17% mortality via immersion and 66.07% after 1 day of spraying.
• TDS showed lower initial efficacy than MNSC post-spraying but comparable long-term effects.

Conclusions:

• TDS exhibits significant molluscicidal activity and stable efficacy in field conditions.
• The overall molluscicidal effect of TDS is comparable to MNSC.
• TDS presents a viable alternative, though its molluscicidal sensitivity is less potent than MNSC.