摘要
[目的]对甜瓜采后主要致腐微生物进行分离鉴定,并筛选出防腐效果最佳的拮抗菌株,丰富甜瓜采后保鲜拮抗菌资源。[方法]利用组织块分离法在腐烂的甜瓜果实中分离致腐菌,采用梯度稀释法从甜瓜种植地土壤分离拮抗菌,通过平板对峙法筛选出拮抗作用较强的生防菌,并通过形态学观察、生理生化测定、生物学鉴定确定其种属,测定拮抗菌对菌丝生长及分生孢子萌发的作用,明确拮抗菌对致腐菌的防治效果。[结果]本研究分离出1株主要病原菌CH-3,通过对ITS、tef和tub基因序列进行BLAST比对及系统发育分析,结合菌落形态特征观察,病原菌CH-3鉴定为尖孢镰刀菌。从甜瓜种植地土壤中分离得到67株细菌,通过拮抗试验得到3株抑菌活性很强的拮抗菌,分别为BG-1、BG-2和BG-3,选取抑菌效果更好的BG-2作为供试菌株,结合生理生化测定、菌落和菌体形态特征观察及16S rDNA、gyrB和rpoB基因序列分析结果,明确拮抗菌BG-2为贝莱斯芽孢杆菌。致病性测定结果表明,致腐菌CH-3对甜瓜有致病性,拮抗菌BG-2对甜瓜致腐菌尖孢镰刀菌CH-3孢子萌发、菌丝生长的相对抑制率分别为90.00%、60.11%。[结论]获得1株拮抗效果最佳的拮抗菌BG-2,鉴定为贝莱斯芽孢杆菌,分离到1株甜瓜主要致腐菌CH-3,鉴定为尖孢镰刀菌。贝莱斯芽孢杆菌BG-2对尖孢镰刀菌CH-3有较强的拮抗作用,致腐菌CH-3对甜瓜有致病性,拮抗菌BG-2能有效抑制甜瓜致腐菌尖孢镰刀菌CH-3孢子萌发和菌丝生长,且拮抗菌浓度越高对孢子萌发的抑制效果越好,在甜瓜采后贮藏及生物保鲜中具有潜在的应用价值。
[Objective]The main spoilage microorganisms in postharvest melon were isolated and identified,and the antagonistic strains with the best preservative effect were screened to enrich the antagonistic bacteria resources for postharvest preservation of melon.[Method]In the study,the tissue block separation method was used to isolate the spoilage bacteria in the rotting melon fruit,and the gradient dilution method was used to isolate the antagonistic bacteria from the soil of the melon planting area.The biocontrol bacteria with strong antagonistic effect were screened by the plate confrontation method,and the species were determined by morphological observation,physiological and biochemi-cal determination and biological identification.The effect of antagonistic bacteria on mycelial growth and conidia germination was determined to clarify the control effect of antagonistic bacteria on spoilage bacteria.[Result]In the study,a major pathogen CH-3 was isolated.Through BLAST alignment and phylogenetic analysis of ITS,tef and tub gene sequences,combined with the observation of colony morphological char-acteristics,the pathogen CH-3 was identified as Fusarium oxysporum.67 strains of bacteria were isolated from the soil of muskmelon planting area.Three strains of antagonistic bacteria with strong antibacterial activity were obtained by antagonistic test,which were BG-1,BG-2 and BG-3,respectively.BG-2 with better antibacterial effect was selected as the test strain,Combined with physiological and biochemical determi-nation,colony and bacterial morphological characteristics observation and 16S rDNA,gyrB and rpoB gene sequence analysis results,the antag-onistic bacteria BG-2 was identified as Bacillus velezensis.The results of pathogenicity test showed that the pathogenic fungus CH-3 was patho-genic to melon.The relative inhibition rates of BG-2 on spore germination and mycelial growth of F.oxysporum CH-3 were 90.00% and 60.11%,respectively.[Conclusion]An antagonistic strain BG-2 with the best antagonistic effect is obtained and
作者
管力慧
牛新湘
刘萍
杨红梅
楚敏
包慧芳
王宁
詹发强
林青
杨蓉
龙宣杞
娄恺
史应武
GUAN Li-hui;NIU Xin-xiang;LIU Ping;YANG Hong-mei;CHU Min;BAO Hui-fang;WANG Ning;ZHAN Fa-qiang;LIN Qing;YANG Rong;LONG Xuan-qi;LOU Kai;SHI Ying-wu(Institute of Microbiology,Xinjang Academy of Agricultural Sciences,Urumqi 830091,China;Cllege of Life Sciences and Technology Xinjiang University,Urumqi 830052,China;Xinjiang Special Environmental Microbiology Laboratory,Urumqi 830091,China;Institute of Soil Fertilizer and Agricultural Water Conservation,Xinjiang Academy of Agricultural Sciences,Urumqi 830091,China;Key Laboratory of Northwest Oasis Agricultural Environment,Ministry of Agriculture and Rural Affairs,Urumqi 830091,China)
出处
《西南农业学报》
CSCD
北大核心
2024年第4期796-804,共9页
Southwest China Journal of Agricultural Sciences
基金
国家自然科学基金地区科学基金项目(31860024)
新疆维吾尔自治区重点研发项目(2021B02004、2022B02053-2、2022A 02005)
国家重点研发项目(2022YFD1400304)。
关键词
甜瓜
致腐菌
拮抗菌
分离
鉴定
Melon
Rotting fungi
Antagonistic bacteria
Isolation
Identification
