牛樟扦插苗之兩種新病害

Two New Diseases on Cinnamomum kanehirai Cuttings

張東柱(Tun-Tschu Chang)

《林業試驗所研究報告季刊》 7卷3期 (1992/09) Pp. 231-236

https://doi.org/10.7075/BTFRI.199209.0231

摘要

牛樟根腐病與葉枯病普遍發生在牛樟扦插苗上。罹患根腐病的苗其根部壞疽腐爛呈黃褐色，最後因根部腐爛而全株萎凋死亡。其病原菌經分離與鑑定證實是Pythium splendens。罹患葉枯病的植株其葉部初期出現大小不一圓形或不規則形的黃褐色至黑褐色病斑，當高濕時呈水浸狀，最後葉枯落葉，幼芽枯死導致苗死亡。其病原菌經分離與鑑定證實是Cylindrocladium clavatum。將上述兩種病原菌分別接種到其為害的部位，均可產生與自然界發生病害相同的病徵。經分離接種的病組織也可獲得相同種的病原菌。 P. splendens之最適生長溫度為30℃，而C. clavatum的最適生長溫度為25℃。C. clavatum在臺灣首次被發現。

關鍵字

牛樟扦插苗 ； 根腐病 ； 葉枯病 ； Pythium splendens ； Cylindrocladium clavatum

並列摘要

Root rot disease and leaf blight disease were commonly observed on Cinnamomum kanehirai Hey, cuttings. The root rot cuttings became dark brown and appeared root lesion, rat and eventually death of cuttings due to disfunction of root transportation. The disease was reproduced by artificial inoculation of the cuttings with the culture of Pythium splendens isolated from the diseased roots. P. splendens was reisolated from diseased tissues of inoculated roots. The leaf blight cuttings appeared leaf necrosis and water soaked spats with round to irrugular blight at various sizes reselling in defoliation, die back and death of cuttings. The disease was reproduced by artificial inoculation of the cuttings with conidia of Cylindrocladium clavatum isolated from diseased leaves. C. clavatum was reisolated from diseased tissues of inoculated leaves. Optimum temperature foe growth of P. splendens and C. clavatum was 30℃ and 25℃, respectively. C. clavatum was new to Taiwan.

並列關鍵字

Cinnamomum kanehirai cuttings ； root rot ； leaf blight ； Pythium splendens ； Cylindrocladium clavatum