马铃薯疮痂病病原菌的分离鉴定及其生长特性分析

Isolation and Identification of Pathogen of Potato Scab and Its Growth Characteristics from Zepu Area in Xinjiang

【目的】研究新疆喀什泽普县阿依库勒乡马铃薯疮痂病病原菌的种类及其生长特性。【方法】采用组织分离法结合柯赫氏法则、显微形态和16S rDNA等方法,分离鉴定马铃薯疮痂病病原菌;分析菌株对不同碳源、氮源的利用能力,以及不同pH的生长能力。【结果】新疆泽普马铃薯疮痂病的病原菌为疮痂链霉菌(Streptomyces acidiscabies),产白色光滑呈自由弯曲状的孢子,能产生黑色素和可溶性色素,可利用葡萄糖等8种碳源和甲硫氨酸(Met)和组氨酸(His)2种氮源,接种健康马铃薯块茎上能产生网纹状甚至凹陷裂口状病斑。【结论】该地区马铃薯疮痂病病原菌最适生长温度为30℃,pH为7,最适碳氮源为葡萄糖和甲硫氨酸,全黑暗利于菌株的生长。

【Objective】The purpose of this study is to determine the species and growth characteristics of potato scab pathogen in Aikule Township,Kashgar Prefecture,Xinjiang,for the potato scab disease affected the yield and quality of potato seriously,and caused great losses to potato industry,especially to virus-free seed potato in Xinjiang.【Method】The pathogen was isolated and identified by tissue separation method combined with Koch's rule,microscopic morphology and 16 S rDNA.Then different carbon sources and nitrogen sources were selected to test its growth characteristics.【Result】Based on its morphological characteristics and 16S rDNA sequence,the pathogen of this disease was identified as Streptomyces acidiscabies from this area,which produced white-smooth curved spores with melanin and soluble pigment.Eight kinds of the carbon sources and two kinds of nitrogen sources were tested its growth period,such as glucose,methionine(Met)and histidine(His)etc.It could produce reticulate netlike scab after inoculatedon healthy potato tubers by smearing the tuber skin with spores suspension.The optimum growth temperature was 30℃,the pH was 7,and the optimum carbon and nitrogen sources were glucose and methionine separately.【Conclusion】The pathogen of the potato scab are isolated and identified from this area,and its growth characteristics were proved in this study,which would be the beneficial research basis for controlling this disease in Xinjiang.