摘要
以改良的 Watanabe(1963b)培养基为基础,对稻白叶枯菌在平板培养条件下的营养需求进一步试验,提出了新的稻白叶枯菌培养基。其成分为蔗糖10g、谷氨酸钠5g、蛋氨酸0.1g、磷酸二氢钾1g、氯化铵1g、氯化镁1g、EDTA 螯合的亚铁离子1ppm、琼脂17g 及水1L,pH6.4～6.7。培养基中加入0.5%胰蛋白胨,可以大大促进此菌的生长,而对许多稻种杂菌(包括 Erwinia herbicola)的促进相对不大。再加入0.2%蛋白胨后与其他各类培养基比较,本研究提出的培养基具有回收率高、菌落出现早等优点,适于稻白叶枯菌的分离。
From studies on nutrient repuirements of 4 Chinese strains of Xanthomonas campestris pv.oryzae in a modified Watanabe's medium,a new medium was developed as follows:sucrose(10g),sodium glutamate(5g),methionine (0.1g),KH_2PO_4(1g),NH_4Cl(1g),MgCl_2·6H_2O(1g),Fe^(++)(1ppm)chelated with EDTA, agar(17g)and H_2O(to 1L)(pH 6.4～6.7).The concentration of each ingredient was optimized based on the number of colonies and time requ- ired for their appearance.In this medium,various concentrations of some nutr- ients were compared to be based upon their effects on growth of the patho- gen strains and 34 contaminants from rice materials.Tryptone(5mg/mL)enhan- ced the growth of X.c.oryzae more than that of many contaminants,including Erwinia herbicola.Peptone(2mg/mL)stimulated growth of X.c.oryzae without promoting excessive contamination.When compared with other media reported for X.c.oryzae,the new medium enriched with tryptone and peptone rendered the highest recovery and earliest appearance of colonies of this bacterium.
关键词
水稻
白叶枯病菌
分离
培养基
Xanthomonas campestris pv.oryzae
selective medium
