辽宁省稻水象甲若干生物学特性变异观察及其机制探讨

Several Variations on the Biology of Rice Water Weevil,Lissorhoptrus oryzophilus and the Mechanism Discussion in Liaoning Province

外来害虫稻水象甲入侵辽宁省30余年,形成分布广泛和稳定的种群。据观察,其生物学特性发生系列明显变异,与早期(2001~2007年)的比较,成虫体色变暗;个体平均重量减少了15%~16.55%;迁移能力明显减弱,表现在新成虫的展开鞘翅个体的比例大量降低,趋光上灯数量大量减少,主要越冬场所分布带离最近稻田的距离明显缩短;成虫的饲养寿命变短了近22%,平均产卵量减少了48%。依据生物进化与生物衰退理论分析认为,这些生物学特性变异的属性为“种群衰退”,其主要原因是环境因素的变化,尤其是农药胁迫增强引起的。

Alien insect pest rice water weevil,Lissorhoptrus oryzophilus has invaded Liaoning Province more than 30 years.They distributed widely and established stable population.By observation,their biology have occurred a series variations.Compare with early stage(2001~2007),rice water weevil in present stage(2019~2022)showed:the body color of adults become darker,and the body weight reduced 15%~16.55%;in artificial rearing,average longevity of adults shortened near 22%,and egg laying amount reduced 48%;the activity of new adults weakened obviously;the hibernal sites were nearer paddy rice field,concentrated in 0~10 m nearby rice field.According to biological evolution,theory of bio-depression and population depression,these variations of rice water weevil in Liaoning Province were typical marks of population depression.It was considered that the cause should be environment changes in especially strength of stress of pesticides.