蟲生線蟲（Steinernema abbasi）對亞洲玉米螟（Ostrinia furnacalis）之田間殺蟲效果

"Field efficacy of the entomopathogenic nematode, Steinernema abbasi, against the Asian corn borer, Ostrinia furnacalis"

"在實驗室內，利用梯溫（15-26℃）以生體繁殖蟲生線蟲（Steinernema abbasi）；在23-26℃下，將S. abbasi接種於大蠟蛾（Galleria mellonella）幼蟲，至58 h，其感染期幼蟲（infective juveniles; IJs）可引起末齡幼蟲死亡率達100%，顯示由此所得之IJs可用於田間殺蟲效力檢定之用。但在20℃下，此線蟲雖可感染寄主，但無法完成其生活史。在田間試驗中，分別測定此線蟲對亞洲玉米螟（Ostrinia furnacalis）的殺蟲及保護玉米果穗之效果。施用40,000 IJs/ear後，線蟲在玉米穗端部及玉米穗中基部之殺蟲效力分別為81.1及16.8%。施用4,000 IJs/ear一次、兩次或3%加保扶（carbofuran）後，玉米被害粒數皆低於對照組；且三處理組中符合可上市玉米穗率顯著高於未處理之對照組。本試驗結果顯示S. abbasi具有對亞洲玉米螟的殺蟲效果及對玉米品質的保護效果，因此其對亞洲玉米螟具有生物防治之潛力。"

"The in vivo production of the entomopathogenic nematode, Steinernema abbasi, was conducted at a temperature gradient from 15 to 26℃. Its infective juveniles (IJs) produced from the infected larvae of Galleria mellonella at 23-26℃ for 58 h could cause 100% mortality of the last instar, indicating that these IJs were suitable for assaying the insecticidal activity of the nematode. However, they were unable to complete their life cycle at 20℃ although they were infective to host insects. Field trials were carried out to evaluate both the control efficacy and corn protection by the nematode against the Asian corn borer, Ostrinia furnacalis. The larval mortality after applying nematodes at 40,000 IJs/ear to the top end or the middle-bottom part of the ear was 81.1 or 16.8%, respectively. The numbers of kernels injured after applying 4,000 IJs/ear once or twice, or 3% carbofuran were all less than the control, and the marketable ears from the treated plants were significantly higher than those from the control group. These experiments revealed appreciable field efficacy of S. abbasi against O. furnacalis, resulting in corn protection. Therefore, S. abbasi seems to be a potential biocontrol agent for the corn borer."