Biological control of phytophagous arthropods in the physic nut tree Jatropha curcas L. in Brazil

Jatropha curcas has a high biofuel oil content, which could replace polluting fuels, and has great potential for large scale monoculture cultivation in the conventional system. We explored the occurrence, spatial distribution and the functional response of the main phytophagous species of this plant and their natural enemies to explore the potential for conservative biological control. We began sampling phytophagous species and predators when J. curcas plants were six months old. The most common species of phytophagous insects were nymphs and adults of Empoasca kraemeri, followed by Frankliniella schultzei and Myzus persicae. Among the predators, Ricoseius loxocheles, Iphiseioides zuluagai, Araneidae, larvae and adults of Psyllobora vigintimaculata and Anthicus sp. were the most frequently encountered. The most common parasitoids were the families Encyrtidae and Braconidae. The highest densities of E. kraemeri and F. schultzei on the edges of the J. curcas crop follow spatial patterns similar to those of their natural enemies I. zuluagai and Anthicus sp. These arthropods can be considered efficient predators of immature stages of E. kraemeri and F. schultzei on J. curcas.麻疯树（Jatropha curcas）生物燃料油含量颇高，可替代污染性燃料，且在常规种植体系下具备大规模单一种植的巨大潜力。本研究探究了该植物主要植食性物种及其天敌的发生规律、空间分布特征与功能响应，以期明确保护型生物防治的应用潜力。当麻疯树植株生长至6个月龄时，我们启动了植食性物种与捕食性天敌的采样工作。最为常见的植食性昆虫为克氏小绿叶蝉（Empoasca kraemeri）的若虫与成虫，其次为花蓟马（Frankliniella schultzei）与桃蚜（Myzus persicae）。捕食性天敌中，最为常见的类群包括Ricoseius loxocheles、祖鲁伊氏绥螨（Iphiseioides zuluagai）、园蛛科（Araneidae）、二十星菌瓢虫（Psyllobora vigintimaculata）的幼虫与成虫，以及蚁形甲属（Anthicus sp.）昆虫。最为常见的寄生性天敌类群为跳小蜂科（Encyrtidae）与茧蜂科（Braconidae）。麻疯树种植园边缘的克氏小绿叶蝉与花蓟马种群密度最高，其空间分布模式与天敌祖鲁伊氏绥螨及蚁形甲属昆虫的分布模式高度相似。上述节肢动物可被视为麻疯树种植园中克氏小绿叶蝉与花蓟马各发育阶段的高效捕食性天敌。