Since the 1980s Tetranychus urticae Koch has dominated Australian cotton due to its ability to develop resistance. Here we give screening data for a range of chemicals tested against T. urticae including abamectin, bifenthrin, diafenthiuron, etoxazole and propargite and speculate why abamectin resistance emerged without warning. Abamectin resistance was not detected in T. urticae in Australian cotton before season 2007–2008 when a few resistant individuals were detected in a single strain. Resistance was detected again in season 2010–2011 and continued to be detected in every subsequent season comprising 80% of strains tested in 2018–2019. We speculate the reason may relate to prophylactic abamectin use to prevent mite flare with Creontiades dilutes Stål mirid sprays. With the introduction of transgenic Bt-cotton, spraying significantly reduced and anecdotally Tetranychus lambi became more abundant. Although T. lambi may now be more common than T. urticae its response to chemical controls is completely unknown. Tetranychus lambi conspecific dose responses were established to support resistance monitoring against abamectin, diafenthiuron and propargite that generated discriminating dose (DD) estimates of 0.0007 g/L abamectin, 0.03 g/L diafenthiuron and 0.7 g/L propargite. These DD were used in season 2018–2019 but resistance was not detected against any product including abamectin. The reason why T. lambi may now dominate despite T. urticae being still resistant is speculated and thought related to the progressive reduction in insecticide use in Australian cotton and/or the changing weed complex in the transgenic cotton era.

自20世纪80年代二斑叶螨科赫占据了主导地位澳棉，由于其产生耐药性的能力。在这里，我们给出了一系列针对测试化学品的筛选数据T.螨包括阿维菌素，联苯菊酯，丁醚脲，乙螨唑和克螨特，并猜测为什么阿维菌素的耐药出现无预警。在2007–2008年季节之前，在澳大利亚棉花的荨麻疹中未检测到阿维菌素抗药性，当时在单个菌株中检测到一些抗药性个体。在2010-2011年季节再次检测到耐药性，并在随后的每个季节继续检测到耐药性，其中包括2018-2019年测试的菌株的80％。我们推测原因可能与预防性使用阿维菌素预防螨虫爆发有关。Creontiades稀释Stål喷雾剂。随着转基因Bt棉的引入，喷洒量明显减少，并且奇特的Tetranychus lambi变得更加丰富。虽然T.兰比现在可能超过普通T.螨及其化学反应控制是完全陌生的。建立了Tetranychus lambi同种剂量反应，以支持对阿维菌素，地芬硫龙和炔丙基的抗性监测，产生的辨别剂量（DD）估计为0.0007 g / L阿维菌素，0.03 g / L泛芬丁酮和0.7 g / L丙炔。这些DD在2018-2019赛季使用，但未检测到对任何产品（包括阿维菌素）的抗药性。之所以T.兰比据推测，尽管可能存在荨麻疹，但仍可能占主导地位，并认为这与澳大利亚棉花中杀虫剂使用的逐步减少和/或转基因棉花时代杂草复合体的变化有关。