撕裂蜡孔菌(Emmia lacerata)SR5抑菌特性及生防潜力评价

Antifungal characteristics and biocontrol potential of Emmia lacerata SR5

【背景】撕裂蜡孔菌(Emmia lacerata)是一种在世界范围内广泛分布的白腐真菌,对植物病原真菌有较好的抑制作用,可作为生防真菌进行开发和利用。【目的】对撕裂蜡孔菌SR5的抑菌能力和胞外产铁载体能力进行测定,挖掘其生防潜力。【方法】采用平板对峙法检测SR5对9种植物病原真菌的抑菌能力,并通过不同浓度的发酵原液测定真菌胞外代谢物的抑菌效果;结合铬天青S(chrome azurol S, CAS)检测法测定真菌产铁载体能力,明确SR5抑菌特性。【结果】SR5以过度生长的方式快速竞争营养和生存空间,拮抗9种植物病原真菌,抑菌率为23.7%–62.7%,对可可毛色二孢(Lasiodiplodia theobromae)的拮抗等级为Ⅳ级,而对其余8种病原真菌的拮抗等级为Ⅲ级,其中对香港丽赤壳(Calonectria hongkongensis)和间座壳(Diaporthe sp.)抑菌效果最佳;CAS检测法表明SR5能产生分泌型铁载体,产铁载体能力中等,最高铁载体活性单位(siderophore unit, SU)为44.1%。【结论】SR5以过度生长方式快速竞争营养和生存空间,而且以分泌胞外抑菌代谢物铁载体的方式发挥生防效应,该研究为撕裂蜡孔菌在生防领域的进一步开发利用提供了理论依据。

[Background]Emmia lacerata,a white-rot fungus with global distribution,has a good inhibitory effect on the fungal pathogens of plants and can be developed as a biocontrol fungus.[Objective]To determine the antifungal ability and siderophore production ability of E.lacerata SR5 and explore its biocontrol potential.[Methods]The antifungal abilities of SR5 against 9 plant pathogens were determined by dual culture method and different concentrations of fermentation supernatants were used to determine the inhibitory effect of the metabolites.The chrome azurol S(CAS)method was employed to determine the siderophore production ability of SR5.[Results]SR5 inhibited 9 plant pathogens quickly in the way of overgrowth by competing for nutrients and survival space,with the inhibition rates of 23.7%–62.7%.It showed the strongest inhibition on Calonectria hongkongensis and Diaporthe sp.,with the antagonism grade IV against Lasiodiplodia theobromae and grade III against the other 8 pathogenic fungi.SR5 demonstrated moderate capacity of producing secretory siderophore,with the highest siderophore unit(SU)of 44.1%.[Conclusion]SR5 plays the role of biocontrol by competing for nutrients and survival space and secreting siderophore,an extracellular anti-microbial metabolite.This study provides a scientific basis for the further development and utilization of E.lacerata in biocontrol.