番茄枯萎病和青枯病拮抗细菌的筛选、评价与鉴定

Screening, Evaluation and Identification of Antagonistic Bacteria against Fusarium oxysporum f. sp. lycopersici and Ralstonia solanacearum

从宁夏银川、江苏沭阳和福建厦门的番茄、辣椒、西瓜等作物根际土壤中,分离纯化获得367株细菌菌株。以番茄枯萎病菌Fusarium oxysporum f.sp.lycopersici和番茄青枯病菌Ralstonia solanacearum为靶标菌,从367株菌株中筛选出对两种病菌皆具有很强拮抗作用的菌株22株。拮抗细菌抑菌物质的研究结果表明:22株拮抗细菌均能分泌蛋白酶;不能分泌几丁质酶;3株细菌能分泌纤维素酶;3株细菌能分泌嗜铁素。盆栽试验结果表明:拮抗细菌PTS-394对番茄枯萎病和青枯病的防效最高,分别为77.4%和80%;菌株H-70、L-1和SJ-280对番茄枯萎病和青枯病的防效均大于60%。对上述4株拮抗细菌进行16S rRNA种属鉴定,均为枯草芽孢杆菌Bacillus subtilis。

Tomato Fusarium wilt and bacterial wilt caused by Fusarium oxysporum and Ralstonia solanacearum are two common diseases throughout tomato-growing areas.Use of antagonistic bacteria to control the diseases can potentially reduce the negative effects of chemical fungicides on vegetable and the environment.Here,we screened and evaluated the control efficiencies of antagonistic bacteria against F.oxysporum f.sp.lycopersici and R.solanacearum in vitro.367 strains were isolated and purified from rhizosphere soil of tomato,pepper and watermelon plant’s in Ningxia,Jiangsu and Fujian provinces.Test on antagonistic ability revealed that 22 strains showed strong and steady antagonism against F.oxysporum and R.solanacearum.All the above 22 strains could produce protease,whereas they could not produce chitinase.Three strains could produce cellulase and siderophore,separately.In pot experiment,strains PTS-394 could control Fusarium wilt and bacterial wilt effectively,with control efficiency of 77.4% and 80%,respectively,and control efficiencies of strains H-70,L-1 and SJ-280 were all above 60%.16S rRNA sequence analysis showed that the four strains were Bacillus subtilis.