酥梨采后灰霉病生防菌株的鉴定及抑菌作用

Identification and Bacteriostasis of Biocontrol Strains Against Gray Mold from Crisp Pear

以微生物拮抗病原菌是防治病害安全高效的可行手段。通过对果实表面微生物进行筛选鉴定,以期得到一株可以有效抑制灰霉病的生物防治菌株。对拮抗菌株H-1进行形态学特征、生理生化特性分析,结合16S r DNA序列分析和gyrB基因序列分析构建系统发育树;采用平板对峙法结合果实伤口试验考察拮抗菌H-1在体外及梨果表面的抑菌作用。结果表明:经鉴定H-I菌株为贝莱斯芽孢杆菌(Bacillus velezensis);B.velezensis H-1在体外条件下可显著抑制灰葡萄孢霉(Botrytis cinerea)、细极链格孢(Alternaria tenuissima)和串珠镰孢菌(Fusarium verticillioides)的菌丝生长,其中对灰葡萄孢霉菌丝的抑制作用最强;果实伤口试验表明,1×1011CFU/mL的B.velezensis H-1可完全抑制梨果表面灰霉菌生长。由此可见,B.velezensis H-1可以有效抑制梨果采后灰霉病的发生。

It was a safe,efficient and feasible way to control diseases by antagonizing pathogenic bacteria with microor⁃ganisms.Screening and identification of microorganisms on the fruit surface were carried out in order to obtain a biolog⁃ical control strain that can effectively inhibit gray mold.Morphological,physiological and biochemical characteristics of the biocontrol strain H-1 against Botrytis cinerea were analyzed,and combined with the 16S rDNA sequence analy⁃sis and gyrB gene sequence analysis to construct a phylogenetic tree.The antifungal effects of antagonistic H-1 on vi⁃tro and pear fruit surface were determined by plate confrontation method combined with fruit wound experiments.H-1 strain was identified as Bacillus velezensis.B.velezensis H-1 could significantly inhibit the hyphae growth of Botrytis ci⁃nerea,Alternaria tenuissima and Fusarium verticillioides on vitro,among which inhibitory effect on Botrytis cinerida hy⁃phae was the strongest.Fruit wound experiments showed that 1×1011 CFU/mL of B.velezensis H-1 could completely in⁃hibit the growth of Botrymyces on the surface of pear fruit.B.velezensis H-1 could effectively inhibit the occurrence of Botrytis cinerea in postharvest pear fruits.