Abstract:

Objective To study the predatory capacity of Culex fuscanus on Aedes albopictus and the relevant influencing factors. Methods Culex fuscanus and Ae. albopictus larvae were collected in the field. Densities of Cx. fuscanus and Ae. albopictus larvae were recorded and the relationship between densities and the predatory capacity of Cx. fuscanus was studied. The surviving status of Ae. albopictus at different temperature and in water inhabited by Cx. fuscanus was investigated. Results When the density of prey fell in a certain range [under 25 Ae. albopictus larvae/(Cx. fuscanus larva·d)], the daily predation by Cx. fuscanus larvae was positively correlated with the density of Ae. albopictus (R=0.942, P<0.01), and the highest number of caught Ae. albopictus larvae was 55.86, as calculated by the Holling's disc equation. When the density of prey remained consistent, the daily predation by Cx. fuscanus larvae was negatively correlated with the density of its own (R=-0.943, P<0.01). Cx. fuscanus larvae could change the quality of water to reduce the survival rate of Ae. albopictus larvae (χ²=8.661, P=0.002). Significant difference in high temperature tolerance was observed between Ae. albopictus and Ae. albopictus larvae (t=7.365, P<0.01). Conclusion The biological control capability of Cx. fuscanus on Ae. albopictus is affected by many factors including temperature and densities of Ae. albopictus and Cx. fuscanus. Further studies are needed to evaluate the actual field efficacy of biological control. Predation of Ae. albopictus by Cx. fuscanus can be used as an attempt of biological control.

Key words: Culex fuscanus, Predation, Aedes albopictus, Larva

摘要：

目的 观察褐尾库蚊对白纹伊蚊的捕食能力及影响因素。方法 采集自然环境下的褐尾库蚊和白纹伊蚊幼虫,观察白纹伊蚊幼虫密度、褐尾库蚊幼虫自身密度与其捕食白纹伊蚊的关系;观察被褐尾库蚊孳生的水体及温度对白纹伊蚊的影响。结果 在一定的猎物密度范围内〔猎物密度25条白纹伊蚊幼虫/(褐尾库蚊幼虫·d)以内〕,褐尾库蚊幼虫的日捕食量和白纹伊蚊幼虫密度呈正相关(R=0.942,P<0.01),根据Holling圆盘方程算出捕食上限为55.86条。猎物密度一定时,褐尾库蚊幼虫的日捕食量和自身密度呈负相关(R=-0.943,P<0.01)。褐尾库蚊幼虫可通过改变水质降低白纹伊蚊幼虫存活率(χ²=8.661,P=0.002)。褐尾库蚊幼虫和白纹伊蚊幼虫对高温的耐受能力差异有统计学意义(t=7.365,P<0.01)。结论 褐尾库蚊对于白纹伊蚊的生物防治能力受温度、白纹伊蚊密度和褐尾库蚊密度等影响,其实际生物防治能力需要通过进一步实验来评价其生物防治的实际效果。利用褐尾库蚊捕食白纹伊蚊可作为生物防制的一种尝试。

关键词: 褐尾库蚊, 捕食, 白纹伊蚊, 幼虫