USDA-ARS, Southeastern Fruit and Tree Nut Research Laboratory, 21 Dunbar Road, Byron, GA 31008, USA.
J Econ Entomol. 2013 Feb;106(1):257-66. doi: 10.1603/ec12302.
Key pecan insect pests include the black pecan aphid, Melanocallis caryaefoliae (Davis), pecan weevil, Curculio caryae (Horn), and stink bugs (Hemiptera: Pentatomidae). Alternative control tactics are needed for management of these pests in organic and conventional systems. Our objective was to evaluate the potential utility of several alternative insecticides including three plant extract formulations, eucalyptus extract, citrus extract-8.92%, and citrus extract-19.4%, and two microbial insecticides, Chromobacterium subtsugae (Martin et al.) and Isaria fumosorosea (Wize). In the laboratory, eucalyptus extract, citrus extract-8.92%, citrus extract-19.4%, and C. subtsugae caused M. caryaefoliae mortality (mortality was reached approximately 78, 83, and 96%, respectively). In field tests, combined applications of I. fumosorosea with eucalyptus extract were synergistic and caused up to 82% mortality in M. caryaefoliae. In laboratory assays focusing on C. caryae suppression, C. subtsugae reduced feeding and oviposition damage, eucalyptus extract and citrus extract-19.4% were ineffective, and antagonism was observed when citrus extract-19.4% was combined with the entomopathogenic nematode, Steinernema carpocapsae (Weiser). In field tests, C. subtsugae reduced C. caryae damage by 55% within the first 3d, and caused 74.5% corrected mortality within 7 d posttreatment. In the laboratory, C. subtsugae and eucalyptus extract did not cause mortality in the brown stink bug, Euschistus servus (Say). Applications of C. subtsugae for suppression of C. caryae, and eucalyptus extract plus I. fumosorosea for control of M. caryaefoliae show promise as alternative insecticides and should be evaluated further.
关键的山核桃虫害包括黑山核桃蚜虫、山核桃叶甲（戴维斯）、山核桃象甲、山核桃小卷蛾（霍恩）和臭虫（半翅目：猎蝽科）。有机和常规系统需要管理这些害虫的替代控制策略。我们的目标是评估几种替代杀虫剂的潜在效用，包括三种植物提取物制剂、桉树提取物、柑橘提取物-8.92%和柑橘提取物-19.4%，以及两种微生物杀虫剂，变色杆菌（马丁等人）和绿僵菌（威泽）。在实验室中，桉树提取物、柑橘提取物-8.92%、柑橘提取物-19.4%和 C. subtsugae 导致 M. caryaefoliae 死亡（死亡率分别约为 78%、83%和 96%）。在田间试验中，绿僵菌与桉树提取物联合应用具有协同作用，可导致山核桃叶甲的死亡率高达 82%。在以抑制 C. caryae 为重点的实验室试验中，变色杆菌减少了取食和产卵损伤，桉树提取物和柑橘提取物-19.4%无效，而柑橘提取物-19.4%与昆虫病原线虫斯氏线虫（Weiser）联合使用时则表现出拮抗作用。在田间试验中，变色杆菌在最初的 3 天内将 C. caryae 的损伤减少了 55%，并在处理后 7 天内造成 74.5%的校正死亡率。在实验室中，变色杆菌和桉树提取物不会导致棕色臭虫 Euschistus servus（塞）死亡。变色杆菌对 C. caryae 的抑制作用，以及桉树提取物加绿僵菌对 M. caryaefoliae 的控制作用，作为替代杀虫剂具有很大的潜力，应进一步评估。
