桑卷叶枯病病原菌的形态特征与分离培养条件

Morphological Characters and Separation Culture Condition of Pathogenic Fungus Causing Mulberry Leaf Burn Disease

桑卷叶枯病是桑树的主要真菌病害之一。采用常规的微生物学试验方法观察病原菌桑单胞枝霉菌(Hormodendrummori Yendo)的形态并研究病原菌的分离培养条件。结果表明,病原菌在PDA培养基上生长良好,形成白色圆形凸状菌落,并能产生大量的暗蓝褐色分生孢子梗和淡灰色分生孢子;菌丝的生长温度为8～40℃,产生分生孢子的温度为10～38℃,分生孢子的致死温度为50～55℃,菌丝生长和分生孢子产生的最适温度为25～30℃;适合菌丝生长的pH为4.5～11.0,最适pH为6～7;相对湿度大有利于菌丝生长和分生孢子的产生与萌发;连续光照可促进产孢。以上结果信息可供研究桑卷叶枯病病原菌的危害特点和建立病害的有效防治方法参考。

Mulberry leaf burn is one of the major fungus diseases in mulberry. Using conventional microbiological experimental methods, morphology of the pathogen Hormodendrum mori Yendo was observed and its separation culture condition was studied. The results showed that the pathogen grew well on PDA medium, forming white round convex colonies with large amount of dark blue conidiophores and grayish conidia. Temperature for hypha growth was 8 -40℃, for conidium formation 10 -38 ℃, and for conidium lethality 50 -55 ℃. The optimum temperature for hypha growth and conidium formation was 25 -30 ℃. pH value for hypha growth was 4.5 - 11.0 with the optimum pH value of 6 -7. High humidity was favorable to growth of hypha, formation and germination of conidia. Continuous illumination could promote sporogenesis of the fungus. The above results provide good reference for studying characteristics of H. mori and developing effective measures to control mulberry leaf burn.