三種生物性農藥對水稻害蟲防治效果評估

Evaluation of the Controlling Efficacy on Rice Insect Pests with Three Biochemicals

鄭明欽(Ming-Ching Cheng) ； 楊大吉(Ta-Chi Yang)

《花蓮區農業改良場研究彙報》 15期 (1998/03) Pp. 12-19

https://doi.org/10.6957/RBHDAIS.199803.0012

摘要

以苦楝精、大蒜精、蘇力菌等三種生物性農藥於網室及田間探討對水稻縱葉蟲（Cnaphalocrocis medinalis）、稻苞蟲（Borbo cinnara Wallace）及二化螟蟲（Chilo suppressalis Walker）之防治效果，試驗分別於網室內以接蟲處理及直接於田間噴藥進行試驗。於網室內將縱捲葉蟲之3－4齡幼蟲接種於盆栽水稻，每盆種植五株水稻並接蟲五隻，隔日後再以上述資材之不同濃度噴施一次，一週後調查若蟲死亡率，結果以蘇力菌1,000倍之效果達87%最接近化學藥劑之93%，其次為大蒜精500倍之73%；苦楝精之效果較差；對螟蟲之致死率，在處理後一週，以化學藥劑之陶斯松乳劑最佳達90%，其他資材之致死率，僅在20～45%之間。田間試驗自蟲害發生始期開始，每隔一週噴施一次共三次，調查結果顯示生物性農藥防治縱捲葉蟲以蘇力菌之效果較佳，其次為苦楝精，大蒜精500倍最差僅有約50%之防治率；三種資材對稻苞蟲之防治與縱捲葉蟲效果相似；對螟蟲之控制則以蘇力菌及蒜頭精500倍之防治效果接近化學農藥防治方法，苦楝精三種濃度（1,000至3,000倍）之防治效果較差亦不穩定。

關鍵字

水稻 ； 害蟲 ； 生物性農藥

並列摘要

Three bio-chemicals, i.e. 4.5％ Neemix, extracts of garlic and Bacillus thuringinesis, were tested for controlling rice insect pests, Cnaphaloctocis medinalis Guene'e (rice leafroller), Borbo cinnara Wallace (rice skipper) and Chilo suppressalis Walker (rice stem borer) both in laboratory and paddy field conditions. In laboratory test, five 3rd. to 4th. instars larvae of rice leafroller, were caged on rice plants, then were sprayed with different bio-chemicals seperately in the following day. One week after, the mortalities of larvae were determined. The result showed that the lethal effect of Bacillus thuringinesis(87%)which was comparable with that treated by chlorpyrifos (93%). The lethal effect of garlic extract (500-fold) was 73%,while Neemix was not effective for control of rice leafroller. The mortality of rice stem borer by Chlorpyrifos was 90 % and those by the biochemicals were in the range of 20∼45%. In field conditions, the biochemicals were sprayed weekly for three times at the beginning of insect pests occurrence, Bacillus thuringinesis was the most effective for control of rice leafroller, followed by the Neemix. Garlic extract(500-fold) provided only 50% controlling efficiency to rice leafrollers. Similar results were also shown in control of rice skippers with these three biochemicals . The effects of Bacillus thuringinesis and garlic extract(500-fold) against rice stem boer were very close to that by treatment with chlorpyrifos, while Neemix with all three concentrations was less effective and unstable.

並列關鍵字

Rice ； Insect pests ； biochemicals