Walzer Andreas, Schausberger Peter
Institute of Plant Protection, Department of Applied Plant Sciences and Plant Biotechnology, University of Natural Resources and Applied Life Sciences, 1190 Vienna, Austria.
Biol J Linn Soc Lond. 2011 Mar;102(3):650-660. doi: 10.1111/j.1095-8312.2010.01593.x.
We studied developmental plasticity under food stress in three female-biased size dimorphic predatory mite species, Phytoseiulus persimilis, Neoseiulus californicus, and Amblyseius andersoni. All three species prey on two-spotted spider mites but differ in the degree of adaptation to this prey. Phytoseiulus persimilis is a specialized spider mite predator, N. californicus is a generalist with a preference for spider mites, and A. andersoni is a broad generalist. Immature predators were offered prey patches of varying density and their survival chances, dispersal tendencies, age and size at maturity measured. Amblyseius andersoni dispersed earlier from and had lower survival chances in low density prey patches than N. californicus and P. persimilis. Age at maturity was not affected by prey density in the generalist A. andersoni, whereas both the specialist P. persimilis and the generalist N. californicus accelerated development at low prey densities. Species-specific plasticity in age at maturity reflects opposite survival strategies when confronted with limited prey: to prematurely leave and search for other food (A. andersoni) or to stay and accelerate development (P. persimilis, N. californicus). In all species, size at maturity was more plastic in females than males, indicating that males incur higher fitness costs from deviations from optimal body size.
我们研究了三种雌性偏多的体型二态性捕食螨类，即智利小植绥螨、加州新小绥螨和安德森钝绥螨，在食物胁迫下的发育可塑性。这三种捕食螨均以二斑叶螨为食，但对这种猎物的适应程度有所不同。智利小植绥螨是一种专门捕食叶螨的捕食者，加州新小绥螨是一种偏好叶螨的广食性捕食者，而安德森钝绥螨是一种宽泛的广食性捕食者。为未成熟的捕食螨提供不同密度的猎物斑块，并测量它们的生存机会、扩散倾向、成熟时的年龄和体型。与加州新小绥螨和智利小植绥螨相比，安德森钝绥螨在低密度猎物斑块中更早扩散，且生存机会更低。广食性的安德森钝绥螨成熟时的年龄不受猎物密度的影响，而专门捕食者智利小植绥螨和广食性的加州新小绥螨在低猎物密度下都会加速发育。成熟时年龄的物种特异性可塑性反映了在面对有限猎物时相反的生存策略：过早离开并寻找其他食物（安德森钝绥螨）或留下来加速发育（智利小植绥螨、加州新小绥螨）。在所有物种中，雌性成熟时的体型比雄性更具可塑性，这表明雄性偏离最佳体型会产生更高的适合度成本。
