一种简便分离香蕉枯萎病菌的选择性培养基

A New Selective Medium to Simplify Isolation of Fusarium oxysporum f.sp.cubense

为探寻在非无菌操作下能从土壤中快速且大量分离检测香蕉枯萎病菌,研制了一种用于检测香蕉枯萎病病原菌的选择性培养基-PCEA,其成分为:马铃薯200g,CuSO4·5H2O0.5g,MgSO4·7H2O0.6g,KH2PO40.1g,敌克松结晶粉(75%)3g,硫酸链霉素0.75g,95%酒精10mL,水1000mL,pH5.8,琼脂18～20g。该培养基与其它常见分离培养基相比,无需无菌操作,且成分简单、检测率显著,抑菌效果好,病菌在其上生长快、菌落典型,是一种较为理想的选择性培养基。

A new selective medium, PCEA, for simple mass isolation of Fusarium oxysporum f. sp. cubense （FOC） from the soil was developed for daily detection. The medium consisted of the following ents per liter distilled water： Potato 200 g, CuSO4.5H2O 0.5 g, MgSO4.7H2O 0.6g,KH2PO4 0.1 g, 75% fenaminosulf 3 g, streptomycin sulfate 0.75 g, 95% ethanol 10mL, pH adjusted to 5.8, and agar 18-20 g. Compared to other selective mediums, this medium was simple and quick to isolate spores from naturally infested soil while rarely contaminated by other microorganisms. The colonies of FOC on the medium were large and white colored, and the mean recovery rate of FOC inoculated in the soil was upto 89.5%. In fact, supplemented with various antibiotics, antifungal substance and nutrients, this selective medium was prepared easily but not necessarily in sterilized conditions. It was simple in ingredients, high in recovery rate and better in inhibitory effect. The FOC grew fast with typical colonies on this medium and is hence believed a better selective medium for daily detection of FOC.