Abstract: 【Abstract】 Objective To research the molluscicidal effect, active components, thermal stability and light stab-ility of endophyte LL3026 （Colletotrichum sp.） from Buddleia lindleyana. Methods The molluscicidal effect of LL3026 against Oncomelania hupensis was determined as referring to the WHO guidelines for laboratory molluscicidal test, and the control experiments were performed with 1 mg/L niclosamide or dechlorinated tap water. The active components from LL3026 were extracted by different polar solvents. The thermal stability and light stability of its extracellular moiety was examined at different temperature （30-100 ℃）, different time （30-150 min） and different illumination time （1-9 d）. Results Immersion test showed that the LC50 values for the LL3026 broth were 50.11, 3.43, and 1.55 mg/L for 24, 48, and 72 h, respectively. The ether extract of LL3026 broth showed the best molluscicidal activity compared with other fractions. Treated with 25 mg/L ether extract for 24, 48, and 72 h, the mortality of O. hupensis was 100%. The molluscicidal activity of LL3026 broth had no change at 80 ℃ for 120 min, and the snail mortality was 100%. A 48 h exposure to LL3026 broth which placed in an artificial climate box with 3 600 lx illumination for 9 d resulted in 86.7% snail mortality. Conclusion The fractions extracted from endophyte LL3026 isolated from B. lindleyana shows molluscicidal effect to O. hupensis.

Key words: Buddleia lindleyana, Endophyte, LL3026, Oncomelania hupensis, Molluscicide