桃采后褐腐病生防酵母菌的筛选及鉴定

为筛选对由美澳型核果褐腐病菌(Monilinia fructicola)引起的桃褐腐病具有抑制作用的酵母菌株,采用平板对峙的试验方法,从新疆北部12个地区分离的102株酵母菌中筛选出7株对桃褐腐病菌具有显著抑制作用的酵母菌株,其中菌株EEQS-7D拮抗活性最强,该菌株对桃褐腐病菌的抑菌率达78.90%。人为打孔接种活体试验结果表明,该菌株可显著降低桃褐腐病发病程度,抑制率达51.83%。生防相关性状检测结果显示,该菌株能够产生蛋白酶,透明圈直径达到34.5 mm,说明EEQS-7D主要通过分泌蛋白酶达到抑制桃褐腐病的效果。通过对菌株EEQS-7D的形态特征观察、生理生化测试以及26S r DNA序列分析,鉴定该菌株为出芽短梗霉(Aureobasidium pullulans)。

Screening and Identification of Yeast Strains to Control Brown Rot of Postharvest Peaches

In order to choose yeast strains with strong antagonistic activity against Monilinia fructicola,which causes peach brown rot,7 yeast strains were selected by the dural culture method from 102 yeast strains collected from 12 sampling sites in northern Xinjiang.In particular,the strain EEQS-7D was the best among these 7 strains,which reduced the growth of M.fructicola by 78.90％.The result of in vivo test illustrated that this strain could significantly reduce the incidence of brown rot on peaches by 51.83％.The strain was capable of producing protease,and the transparent circle diameter reached 34.5 mm,which indicated that EEQS-7D could inhibit peach brown rot disease mainly by secreting protease.The strain EEQS-7D was identified as Aureobasidium pullulans based on its morphological observation,physiological and biochemical determination and 26S rDNA sequence analysis.