Department of Plant Pathology, University of Kentucky, Lexington, Kentucky 40546.
Appl Environ Microbiol. 1985 Mar;49(3):568-71. doi: 10.1128/aem.49.3.568-571.1985.
The presence of an endophytic fungus, Acremonium coenophialum, in tall fescue (Festuca arundinacea) deterred aphid feeding by Rhopalosiphum padi and Schizaphis graminum. Both species of aphid were unable to survive when confined to endophyte-infected tall fescue plants. Feeding deterrents and toxic factors to R. padi and Oncopeltus fasciatus, large milkweed bug, were primarily associated with a methanol extract obtained when endophyte-infected tall fescue seed was serially extracted with hexane, ethyl acetate, and methanol. The concentrations of pyrrolizidine alkaloids were determined to be 30 to 100 times greater in the methanol extract than in the hexane and ethyl acetate extracts.
内生真菌 Acremonium coenophialum 的存在抑制了禾叶虻 Rhopalosiphum padi 和禾谷缢管蚜 Schizaphis graminum 的取食。当这两种蚜虫被限制在感染内生真菌的高羊茅植物中时,它们都无法存活。对禾叶虻和大草蛉 Oncopeltus fasciatus 的取食抑制因子和有毒因子主要与用正己烷、乙酸乙酯和甲醇依次提取感染内生真菌的高羊茅种子获得的甲醇提取物有关。在甲醇提取物中的吡咯里西啶生物碱的浓度比在正己烷和乙酸乙酯提取物中的浓度高 30 到 100 倍。