Department of Phytotechnics, Federal University of Ceará, Fortaleza, Ceará, Brazil.
Faculty of Engineering, Agronomic Engineering program, University of Magdalena, Magdalena, Santa Marta, Colombia.
Exp Appl Acarol. 2024 Dec;93(4):831-845. doi: 10.1007/s10493-024-00964-x. Epub 2024 Sep 25.
Raoiella indica Hirst has rapidly and widely spread throughout the New World since 2004, primarily infesting coconut palms and interacting with the predator Amblyseius largoensis (Muma). Although A. largoensis feeds on R. indica at all stages of development, it cannot naturally reduce its population to levels that do not impact the host plant. Raoiella indica possesses dorsal setae that secrete exudates during all post-embryonic developmental stages, and females have a behavior that deliberately deposits droplets on the freshly laid egg, possibly as a defense strategy against predation in vulnerable stages. In this context, we analyzed whether the presence or absence of droplets in R. indica eggs affects predation using A. largoensis as a biological model. Thus, we evaluated whether some biological and behavioral characteristics of A. largoensis could be affected by the consumption of R. indica egg masses washed or unwashed with water. Also, we performed a chemical analysis of the droplets exuded by R. indica and provided a description of the oviposition behavior of R. indica. The predator showed a higher consumption rate and preference for washed eggs. The results suggest that the exudate droplets have defensive functions, which are incorporated by the female onto the egg during oviposition and subsequently during a patrolling behavior, as they lose their effect after being washed with water. Although the droplets do not prevent the predator from feeding, they reduce the number of R. indica eggs consumed without affecting the growth of A. largoensis.
印度叶螨（Raoiella indica）自 2004 年以来迅速在新世界广泛传播，主要侵害椰子棕榈，并与捕食者宽须螨（Amblyseius largoensis）相互作用。尽管宽须螨在印度叶螨的所有发育阶段都以其为食，但它无法自然地将其种群减少到不对宿主植物造成影响的水平。印度叶螨在所有的胚胎后发育阶段都具有分泌分泌物的背毛，并且雌螨有一种行为，即故意将液滴沉积在新产下的卵上，这可能是一种在脆弱阶段抵御捕食的防御策略。在这种情况下，我们分析了印度叶螨卵中是否存在液滴是否会影响以宽须螨为生物模型的捕食。因此，我们评估了宽须螨的一些生物学和行为特征是否会因食用用水冲洗或未冲洗的印度叶螨卵而受到影响。此外，我们还对印度叶螨分泌的液滴进行了化学分析，并对印度叶螨的产卵行为进行了描述。捕食者对冲洗过的卵表现出更高的消耗率和偏好。结果表明，这些分泌物液滴具有防御功能，这些功能在产卵期间和随后的巡视行为中被雌螨整合到卵上，因为它们在用水冲洗后会失去作用。尽管液滴不会阻止捕食者进食，但它们会减少被消耗的印度叶螨卵的数量，而不会影响宽须螨的生长。
