BACKGROUNDAcanthacoccus lagerstroemiae (crape myrtle bark scale, CMBS) is an exotic scale insect that feeds on the sap of crape myrtle trees. Heavy infestations of CMBS reduce flowering and honeydew promotes sooty mold growth on the leaves and branches, reducing the aesthetic value of crape myrtle trees in urban landscapes. Lady beetles (Coleoptera: Coccinellidae) are generalist predators that feed on CMBS. Several laboratory and field studies have demonstrated the attraction of lady beetles to olfactory and visual cues. We evaluated lady beetles’ responses to olfactory lures and yellow visual attractants on infested potted and landscape trees to increase natural enemy recruitment and reduce dependence on chemical control methods.RESULTSGas chromatography mass spectrometry analysis showed that limonene is the dominant volatile compound released by crape myrtles infested with CMBS. Limonene and methyl salicylate lures, alone or in combination, failed to reduce CMBS or recruit additional lady beetles to infested trees in all experiments. Yellow rectangular panels placed 1 m above the base of an infested tree recruited up to twofold more lady beetles than control trees; however, this was not statistically significant. A significant reduction in CMBS was observed on infested trees with yellow rectangular panels placed in the canopy.CONCLUSIONYellow rectangular panels are more likely to recruit lady beetles than limonene or methyl salicylate lures in an urban landscape. Management of CMBS is currently achieved using systemic insecticides. This study provides a basis for conservation biological control of CMBS through the recruitment of lady beetles, a significant advancement toward integrated management of this exotic pest. © 2024 Society of Chemical Industry.

中文翻译：

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城市景观紫薇树皮鳞片保护生物防治的嗅觉和视觉线索评价


背景紫薇皮球菌（紫薇树皮鳞片，CMBS）是一种外来的鳞片昆虫，以紫薇树的汁液为食。CMBS 的严重侵扰减少了开花，蜜露促进了叶子和树枝上的烟灰霉菌生长，降低了紫薇树在城市景观中的审美价值。瓢虫（鞘翅目：Coccinellidae）是以 CMBS 为食的多面手捕食者。一些实验室和实地研究表明，瓢虫对嗅觉和视觉线索的吸引力。我们评估了瓢虫对受感染的盆栽和景观树上的嗅觉诱饵和黄色视觉引诱剂的反应，以增加天敌招募并减少对化学防治方法的依赖。结果Gas 色谱质谱分析表明，柠檬烯是紫薇被 CMBS 侵染后释放的主要挥发性化合物。在所有实验中，柠檬烯和水杨酸甲酯诱饵单独或组合使用都未能减少 CMBS 或向受感染的树木招募额外的瓢虫。放置在受侵染树木基部上方 1 m 处的黄色矩形板招募的瓢虫数量是对照树的两倍;然而，这在统计学上并不显著。在树冠中放置黄色矩形面板的受侵染树木上观察到 CMBS 显着减少。结论在城市景观中，矩形板比柠檬烯或水杨酸甲酯诱饵更有可能招募瓢虫。目前使用内吸性杀虫剂来管理 CMBS。这项研究为通过招募瓢虫对 CMBS 进行保护性生物控制提供了基础，这是这种外来害虫综合管理的重大进展。© 2024 化工学会.