由Phomopsis destruens引起之甘藷基腐病

Occurrence of Foot Rot Disease of Sweet Potato Caused by Phomopsis destruens in Taiwan

黃巧雯(C. W. Huang) ； 莊明富(M. F. Chuang) ； 曾顯雄(S. S. Tzean) ； 楊宏仁(H. R. Yang) ； 倪蕙芳(H. F. Ni)

《植物病理學會刊》 21卷1期 (2012/03) Pp. 47-52

https://doi.org/10.6649/PPB.201203_21(1).0006

摘要

甘藷基腐病於2008~2011年間於台灣之甘藷田陸續發現，受害植株地上部生長勢衰落、葉片黃化枯萎、藤蔓乾枯死亡，由於乾枯部位緊鄰塊根生長處，因此導致罹病植株幾乎完全無法生產塊根，且由本病害亦會感染塊根組織部位，造成水浸狀影響甘藷品質。本研究自罹病病株莖蔓分離得到菌株（SPPD-1），以PDA培養時，該菌菌絲生長緩慢，於25℃下培養20天後，培養基呈現淡褐色，菌落稍有皺摺、邊緣不整形。本菌會產生兩型分生孢子，其中一型為單孢、透明無色、圓筒狀或卵形、兩端具有圓形油滴之甲型分生孢子（α-conidia），於罹病組織或人工培養過程中皆會產生；另一型則為次紡錘型，具有多細油滴、一端突尖或圓鈍，另端稍呈截頭狀，一邊略彎之丙型分生孢子（γ-conidia），僅偶爾於罹病組織上發現，以PDA培養時並未產生絲狀或一端彎曲之乙型分生孢子。依據本病害之病徵表現、病原菌形態特徵、分子標記及文獻資料比對，將此菌鑑定為Phomopsis destruens (Harter) Boerema。經人工接種孢子懸浮液於台農57號甘藷健康苗後，發現P. destruens對甘藷具有病原性，為引起甘藷基腐病之病原菌。本病害描述及病原記錄為台灣病害之首報。

關鍵字

甘藷 ； 基腐病 ； Phomopsis destruens

並列摘要

Foot rot disease of sweet potato (Ipomoea batatas) was found in major sweet potato production areas in Taiwan during 2008-2011. The symptoms include yellowing of leaves, necrotic lesions on vine, wilting of the sweet potato plants. The fungus isolated from diseased tissue grew slowly. The fungal colony could produce brown pigments and diffused into the agar medium cultured on PDA at 25°C for 20 days, and also displayed slightly zonate, sulcate and wavy edge. The fungus generated two types of conidia from stromatic pycnidia. One type conidia were one-celled, hyaline, oblong or oval, 2-guttulated α-conidia; the other type conidia were clavate subcylindrical slightly curved γ-conidia only found on diseased host tissues. The causative fungus was identified as Phomopsis destruens (Harter) Boerema based on symptoms, morphological characteristics and ITS rDNA sequence blasting on NCBI GenBank database. The pathogenicity test of P. destruens toward sweet potato host was proved and fulfilled the Koch's postulates. To our knowledge, this is the first report on the occurrence of foot rot disease of sweet potato caused by Phomopsis destruens in Taiwan.

並列關鍵字

Sweet potato ； Ipomoea batatas ； Foot rot ； Phomopsis destruens