Khun Kim Khuy, Ash Gavin J, Stevens Mark M, Huwer Ruth K, Wilson Bree A L
Faculty of Agronomy, Royal University of Agriculture, P.O. Box 2696, Dangkor District, Phnom Penh, Cambodia; Centre for Crop Health, Institute for Life Sciences and the Environment, University of Southern Queensland, Queensland 4350, Australia.
Centre for Crop Health, Institute for Life Sciences and the Environment, University of Southern Queensland, Queensland 4350, Australia.
J Invertebr Pathol. 2020 Jul;174:107437. doi: 10.1016/j.jip.2020.107437. Epub 2020 Jun 25.
Macadamia seed weevil, Kuschelorhynchus macadamiae Jennings and Oberprieler, is a major pest of macadamia in eastern Australia, causing yield losses of up to 15%. Current control methods involve two applications of acephate per season but more recently have moved to a single application of indoxacarb, combined with the collection and destruction of fallen nuts that contain developing larvae. As a first step towards reducing the dependence of the industry on synthetic insecticides, we tested six isolates of M. anisopliae, six isolates of B. bassiana and one commercial B. bassiana product (Velifer® biological insecticide) against adult macadamia seed weevil under laboratory conditions. All isolates were pathogenic against adult weevils with M. anisopliae accession ECS1/BRIP 70272 and B. bassiana accession B27/BRIP 70267 causing 97.5% and 92.5% mortality 12 days after being treated at 1 × 10 conidia/mL. Isolates ECS1/BRIP 70272 and B27/BRIP 70267 had the shortest LT values of 5.13 days and 5.37 days respectively. The median lethal concentrations (LC) for ECS1/BRIP 70272 and B27/BRIP 70267 were 1.48 × 10 and 1.65 × 10 conidia/mL respectively. Results of this study indicate that M. anisopliae accession ECS1/BRIP 70272 and B. bassiana accession B27/BRIP 70267 have considerable potential for K. macadamiae control, and should be developed into biological insecticides for integration into macadamia pest management programs.
澳洲坚果种子象甲，即Kuschelorhynchus macadamiae Jennings和Oberprieler，是澳大利亚东部澳洲坚果的主要害虫，可导致高达15%的产量损失。目前的防治方法是每季使用两次乙酰甲胺磷，但最近已改为单次使用茚虫威，并结合收集和销毁含有发育中幼虫的落果。作为该行业减少对合成杀虫剂依赖的第一步，我们在实验室条件下测试了六种绿僵菌分离株、六种白僵菌分离株和一种市售白僵菌产品（Velifer®生物杀虫剂）对成年澳洲坚果种子象甲的防治效果。所有分离株对成年象甲均有致病性，绿僵菌菌株ECS1/BRIP 70272和白僵菌菌株B27/BRIP 70267在以1×10分生孢子/毫升处理12天后，死亡率分别为97.5%和92.5%。菌株ECS1/BRIP 70272和B27/BRIP 70267的最短致死时间（LT）分别为5.13天和5.37天。ECS1/BRIP 70272和B27/BRIP 70267的半数致死浓度（LC）分别为1.48×10和1.65×10分生孢子/毫升。本研究结果表明，绿僵菌菌株ECS1/BRIP 70272和白僵菌菌株B27/BRIP 70267在防治澳洲坚果种子象甲方面具有很大潜力，应开发成生物杀虫剂，纳入澳洲坚果害虫管理计划。
