Prado Julia, Quesada Carlos, Gosney Michael, Mickelbart Michael V, Sadof Clifford
Department of Entomology, Purdue University, West Lafayette, IN 47907-2089.
Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47907-2089. Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907-2089.
J Econ Entomol. 2015 Jun;108(3):1221-7. doi: 10.1093/jee/tov105. Epub 2015 May 6.
Although leaf nitrogen (N) has been shown to increase the suitability of hosts to herbivorous arthropods, the responses of these pests to N fertilization on susceptible and resistant host plants are not well characterized. This study determined how different rates of N fertilization affected injury caused by the potato leafhopper (Empoasca fabae Harris) and the abundance of maple spider mite (Oligonychus aceris (Shimer)) on 'Red Sunset' red maple (Acer rubrum) and 'Autumn Blaze' Freeman maple (Acer×freemanii) during two years in Indiana. N fertilization increased leaf N concentration in both maple cultivars, albeit to a lesser extent during the second year of the study. Overall, Red Sunset maples were more susceptible to E. fabae injury than Autumn Blaze, whereas Autumn Blaze maples supported higher populations of O. aceris. Differences in populations of O. aceris were attributed to differences between communities of stigmaeid and phytoseiid mites on each cultivar. Injury caused by E. fabae increased with N fertilization in a dose-dependent manner in both cultivars. Although N fertilization increased the abundance of O. aceris on both maple cultivars, there was no difference between the 20 and 40 g rates. We suggest the capacity of N fertilization to increase O. aceris on maples could be limited at higher trophic levels by the community of predatory mites.
尽管叶片氮素（N）已被证明会增加寄主对植食性节肢动物的适宜性，但这些害虫在易感和抗性寄主植物上对氮肥的反应尚未得到充分描述。本研究确定了不同氮肥施用量如何影响马铃薯叶蝉（Empoasca fabae Harris）造成的伤害以及印第安纳州两年间‘红日落’红枫（Acer rubrum）和‘秋焰’弗里曼枫（Acer×freemanii）上枫木红叶螨（Oligonychus aceris (Shimer)）的数量。氮肥增加了两个枫木品种叶片中的氮浓度，尽管在研究的第二年增幅较小。总体而言，‘红日落’枫比‘秋焰’枫更容易受到马铃薯叶蝉的伤害，而‘秋焰’枫上的枫木红叶螨数量更多。枫木红叶螨数量的差异归因于每个品种上跗线螨和植绥螨群落的差异。两个品种中，马铃薯叶蝉造成的伤害均随氮肥施用量的增加呈剂量依赖性增加。尽管氮肥增加了两个枫木品种上枫木红叶螨的数量，但20克和40克施用量之间没有差异。我们认为，在较高营养水平上，氮肥增加枫木上枫木红叶螨数量的能力可能受到捕食螨群落的限制。
