关键词: 草莓根腐病, 新棒状拟盘多毛孢, 贝莱斯芽胞杆菌, 解淀粉芽胞杆菌, 枯草芽胞杆菌

Abstract: In order to obtain the antagonistic bacteria to Neopestalotiopsis clavispora, three strains of antagonistic bacteria were identified, namely Bacillus velezensis-17, Bacillus amyloliquefacen-27 and Bacillus subtilis-Y1-7, and the plate confrontation test of indoor target pathogens and the broad-spectrum verification test of biocontrol effect were performed in this paper. The microscopical observation of 10×4  and 10×10 times of the edge mycelium of the bacteriostatic circle was carried out to detect whether the metabolites of the three biocontrol bacteria contained the promoting biomass and lipopeptide active antiviral substances such as indoleacetic acid (IAA) and iron carrier. The pot and field experiments were designed to detect the effects of disease prevention, growth promotion and production increase. The results showed that: the three biocontrol strains had antagonistic effects on the target pathogens and other six pathogens, such as Botrytiscinerea Pers., and the mycelia on the edge of the inhibition zone appeared deformities such as thinning, twisting and increasing branches. The results of color test of fermentation broth showed that IAA and iron carrier were produced by the tested strains, and the crude extracellular extract of the tested strains had the effect of antagonizing N. clavispora. The above results preliminarily proved that the three biocontrol strains had the potential of promoting growth and disease resistance. Pot experiments showed that the prevention effect was better than the therapeutic effect, and the prevention effect of complex antagonistic bacteria was better than each single one, the control effect could be 73.68%. Field experiments showed it was better on both disease control and yield increasing with complex bacteria, the control effect reached 57.18%~66.00% and the yield increase of per hectare reached 12.97%~37.99%. Pot and field experiments showed that the three strains of biocontrol bacteria had the effect of promoting growth, disease control and increasing production respectively, and the compound effect of three strains of biocontrol bacteria was the best.

Key words: strawberry root rot, Neopestalotiopsis clavispora, Bacillus velezensis, Bacillus amyloliquefacen, Bacillus subtilis