Bacillus Pumilus引起的山藥細菌性葉斑病

2008年起，陸續在臺北士林、臺中霧峰及南投埔里等山藥栽培地區，發現山藥植株出現不規則形壞疽病斑，且病斑周圍具黃暈，隨後逐漸擴大，嚴重者葉片乾枯萎凋。分離所得細菌，經柯霍氏法則確認具有病原性。進一步進行生理生化、Biolog、脂肪酸組成、專一性引子對聚合酶連鎖反應以及16S rDNA定序等病原菌的生理生化及分子鑑定分析，結果顯示該病原菌為Bacillus pumilus，並根據其引起之病徵，定名為山藥細菌性葉斑病。B. pumilus可於CVP培養基上形成淺凹，致腐試驗顯示該病原菌對山藥塊莖及馬鈴薯塊莖均有致腐能力，對於白菜葉梗則不具致腐能力。測試10種藥劑對B. pumilus菌株的抑制圈大小，依序為歐索林酸、鏈四環黴素、鋅錳乃浦、多保鏈黴素、氫氧化銅、鹼性氯氧化銅、鏈黴素、三元硫酸銅、嘉賜銅及嘉賜黴素等，其中歐索林酸之抑制效果明顯優於其他藥劑。此為全世界首次Bacillus pumilus危害山藥之紀錄。

關鍵字

山藥；葉斑病； Bacillus pumilus ；藥劑感受性

並列摘要

In 2008, a new, moderately sever bacterial leaf spot disease was found on yam (Dioscorea spp.) leaves in commercial plantations throughout the central and northern Taiwan. At early stage, infected leaves showed brownish, water-soaked lesions. Later, the lesions turned black with yellow halos. In severe cases, the diseased leaves become wilted and eventually fall. The causal agent of the disease was isolated and identified to be Bacillus pumilus based on the results obtained from Biolog, fatty acid analysis, polymerase chain reaction with specific primers, and 16S rDNA sequencing. The pathogen is capable of digesting pectate on CVP medium, macerating potato and yam tubers, but it cannot macerate the petioles of Chinese cabbage (Brassica rapa). Disk diffusion tests were conducted and showed that oxolinic acid has better control efficacy in comparison with the other 9 commercial pesticides. This is the first report of Bacillus pumilus that causes yam leaf spot disease in the world.

並列關鍵字

Dioscorea spp. ； leaf spot ； Bacillus pumilus ； agrochemical screening

國際替代計量

Bacillus Pumilus引起的山藥細菌性葉斑病

全文下載

主題瀏覽