一株草莓灰霉病生防菌HN1-3的分离、鉴定及其基因组测序分析OA

[Objective]To provide new resources for microbial control of strawberry gray mold,the biocontrol bacteria with significant control effect on strawberry gray mold were isolated,and whether the strain had growth-promoting ability and broad-spectrum antibacterial activity was detected.Combined with genome analysis,the biocontrol mechanism of the strain was preliminary explored.[Method]Endophytic bacteria of strawberry with significant antagonistic effect were screened by plate confrontation method.The strains were identified by morphological,phys-iological and biochemical,16S rDNA and gyrB sequence analysis.The growth-promoting effect and extracellular enzyme secretion ability of the strain were determined by detection medium,and its bacteriostatic spectrum was determined by plate confrontation method.Functional gene annotation and secondary metabolite analysis were performed by whole genome sequencing.[Result]Through the plate confrontation test,a strain of Burkholderia gladioli HN1-3 with significant antagonistic effect on strawberry gray mold HM was identified,and the inhibition rate was 86.72％.HN1-3 could dissolve phosphorus,fix nitrogen and secrete siderophore,which had the potential to promote the growth of strawberry.The cellulase and chitinase secreted by HN1-3 could swell and distort the mycelium of pathogenic bacteria.The strain HN1-3 had different antagonistic effect on six pathogenic bacteria,such as Colletotrichum gloeosporioides,Colletotrichum fructicola and Fusarium astigmat-ic,and the inhibition rate was from 56.83％to 81.17％.According to functional gene annotation and metabolic system analysis,it was specu-lated that HN1-3 could secrete some hydrolases,proteins related to resistance mechanism and proteins that promoted colonization.At the same time,it could also synthesize antibacterial substances such as Caryoynencin and Rhizomide,and a variety of antibiotics such as Sulfazecin and Enacyloxin ⅡA.[Conclusion]The endophytic bacteria HN1-3 screened in the study has significant growth-promoting effect and broad-spec-trum resistance,which has potential application value for the prevention and control of strawberry gray mold,and provides a new theoretical basis and approach for the biological control of strawberry gray mold.