The production of almonds and pistachios in California’s Central Valley employs insecticides for the management of their primary pest, navel orangeworm. The pyrethroid Bifenthrin is commonly used, and now a strain of Amyelois transitella Walker (Lepidoptera: Pyralidae) (R347) obtained from Kern County almond orchards with a history of Bifenthrin use has acquired >110-fold resistance toward pyrethroids. One method to improve control is to use additives and spray adjuvants, which are applied simultaneously with an insecticide to increase coverage and/or duration of control. We tested 2 levels of the naturally occurring clay Kaolin as an additive, alone and in combination with either Bifenthrin or the diamide Chlorantraniliprole, to determine if it could reduce feeding damage and decrease survival of pyrethroid-resistant A. transitella on almonds in the laboratory and improve the efficacy of Chlorantraniliprole in the field. Larval performance was measured for the strains R347 and ALM (34.7-fold resistance compared to susceptible lab strain) reared on treated almonds. Strain R347 had 1.9-fold greater survival and caused 1.3-fold more feeding damage than strain ALM across all treatments, although both strains were susceptible to the combination of Kaolin + insecticide. Kaolin synergized Bifenthrin for R347, decreasing survival by 10.0%. Kaolin did not reduce feeding damage for either strain. When combined with insecticide, feeding damage was similar to insecticide alone, but the addition of Kaolin to the insecticide generally decreased survival more than the insecticide alone. In the field, the addition of Kaolin to Chlorantraniprole during application helped retain activity against this challenging pest.

中文翻译：

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高岭土作为抗杀虫剂脐橙虫（鳞翅目：螟科）的管理替代品

加州中央山谷的杏仁和开心果生产使用杀虫剂来控制主要害虫——脐橙虫。拟除虫菊酯联苯菊酯是常用的，现在从具有联苯菊酯使用历史的克恩县杏仁园获得的一种Amyeloistransitella Walker菌株（鳞翅目：Pyralidae）（R347）已经获得了对拟除虫菊酯>110倍的抗性。改善控制的一种方法是使用添加剂和喷雾助剂，它们与杀虫剂同时施用以增加覆盖范围和/或控制持续时间。我们测试了 2 个浓度的天然粘土高岭土作为添加剂，单独使用以及与联苯菊酯或二酰胺氯虫苯甲酰胺结合使用，以确定它是否可以在实验室中减少摄食损害并降低拟除虫菊酯抗性 A.transitella 在杏仁上的存活率，以及提高氯虫苯甲酰胺的现场药效。测量了在处理过的杏仁上饲养的 R347 和 ALM 菌株的幼虫性能（与易感实验室菌株相比，耐药性为 34.7 倍）。在所有处理中，R347 菌株的存活率比 ALM 菌株高 1.9 倍，造成的摄食损害多 1.3 倍，尽管这两种菌株都对高岭土 + 杀虫剂的组合敏感。高岭土与联苯菊酯对 R347 有协同作用，使存活率降低 10.0%。高岭土并没有减少这两种菌株的进食损害。当与杀虫剂结合使用时，摄食损害与单独使用杀虫剂相似，但在杀虫剂中添加高岭土通常比单独使用杀虫剂更能降低存活率。在田间，在施用过程中向氯虫酰胺中添加高岭土有助于保持针对这种具有挑战性的害虫的活性。