桃树根部内生真菌ZJ-4的分离鉴定及其对桃褐腐病的抑制效果

自桃树根部组织中分离能够防治桃褐腐病害的内生拮抗真菌,并从细胞学水平对其抑制机理进行了初步的探究。采用两点对峙法筛选抑制桃褐腐病菌Monilinia fructicola的内生拮抗真菌,通过菌落形态学特点观察及ITS基因测序分析,初步鉴定内生拮抗真菌的系统发育学地位;采用果实离体实验检测内生拮抗真菌的抗菌效果;使用电子显微镜观察被内生拮抗真菌抑制的桃褐腐病菌丝、孢子的形态以及细胞结构的变化。分离得到的内生真菌ZJ-4对桃褐腐病防效高且稳定,初步鉴定为篮状菌属Talaromyces;果实离体试验表明,内生真菌ZJ-4明显降低了桃褐腐病的发病率;通过电子显微镜观察到被内生真菌ZJ-4抑制的桃褐腐病菌丝及孢子表面粗糙凹陷,畸形现象严重,胞质溶胶收缩凝聚,细胞内部出现大量的空腔。本研究筛选的ZJ-4对桃褐腐病原菌的生长有明显的抑制作用,为开发应用该菌株提供参考。

Isolation and identification of Endophytic Fungus ZJ-4 from Peach Roots and Its Inhibitory Effect against Monilinia fructicola

The antagonistic endophytic fungi against peach brown rot (Monilinia fructicola) were selected from the roots of peach trees and carried out initially deep probe on their inhibitory mechanism at cytological level. Two points confrontation method was adopted to screen out the endophytic fungi against M. fructicola. Adopting observation of their morphological features of colony and analysis of ITS gene sequencing their phylogenetic sites were initially identified. The inhibitory effect of endophytic fungi were tested using fruits in vitro experiment, the change of mycelia, spore morphology, and cellular structure of peach brown rot were observed under electron microscope. The controlling effect of the isolated and obtained endophytic fungus ZJ-4 against peach brown rot was high and stable, the ZJ-4 was initially identified as Talaromyces; The in vitro experiment of fruits showed that ZJ-4 reduced the incidence of peach brown rot significantly. Under electron microscopic observation, the mycelia and conidia of M. fructicola inhibited by ZJ-4 was rough concave, and malformation phenomena were serious. The cytosol was condensation and shrinkage, and a large amount of cavities were observed inside the cells. The ZJ-4 screened in this experiment had significant inhibition against the growth of M. fructicola, and laid the theoretical basis to develop and apply the strain.