Abstract

Diaphorina citri Kuwayama is a serious insect pest of citrus worldwide due to the capacity to transmit causal agent of the huanglongbing. Mineral oils are recommended in the integrated pest management programs to prevent resistance development. The primary objective of this study was to determine emergence inhibition and antifeedant effect of three mineral oils with similar n-paraffin carbon number against D. citri. The results of topical contact toxicity showed that Antong was the most toxic with 50% lethal concentration value of 189 ng/insect. Each mineral oil at the concentrations of 0.1, 0.2 and 0.5% (v/v) significantly inhibited the emergence of adults from treated fifth-instar nymphs, and 0.5% (v/v) of the oils had a long residue activity that they inhibited over 56% adult emergence up to 10 days. We found significant repellency of D. citri from citrus tree resets that were treated with mineral oils compared with control. 0.5% (v/v) of the mineral oils significantly inhibited feeding of D. citri adults with reduction of 39–68% honeydew, and the nymphs that fed on citrus leaves treated with different concentrations raised heads and upper abdomens to form a half-erect posture. Our studies indicated that mineral oils could effectively reduce or suppress the spread of HLB by repellency and less feeding, as well as emergence inhibition to reduce D. citri populations.

摘要

由于能够传播黄龙病的病原体，柑橘木虱是世界范围内严重的柑橘害虫。综合虫害管理计划中推荐使用矿物油，以防止产生抗药性。本研究的主要目的是确定具有相似正链烷烃碳数的三种矿物油对D. citri的出苗抑制和拒食效果. 局部接触毒性结果表明，安通毒性最强，50%致死浓度值为189纳克/只昆虫。浓度为 0.1、0.2 和 0.5% (v/v) 的每种矿物油均显着抑制经处理的五龄若虫成虫的出现，并且 0.5% (v/v) 的油具有长期残留活性，它们抑制超过 56% 的成虫羽化长达 10 天。我们发现与对照相比，用矿物油处理的柑橘树复位对D. citri有显着的驱避作用。0.5% (v/v) 的矿物油显着抑制了D. citri的摄食成虫减少了 39-68% 的蜜露，若虫以不同浓度处理的柑橘叶为食，抬起头和上腹部，形成半直立姿势。我们的研究表明，矿物油可以通过驱避和减少进食以及出现抑制作用来减少柑橘类果蝇种群，从而有效减少或抑制 HLB 的传播。