3种芽孢杆菌菌剂对黄瓜枯萎病的防效及其作用机制初探

以含有黄瓜枯萎病病原菌(尖孢镰刀菌)的病土为材料,采用盆栽试验研究巨大芽孢杆菌B213、多粘类芽孢杆菌B207和枯草芽孢杆菌B204单独或联合施用对黄瓜枯萎病的防效,并对其作用机制进行初步分析。结果显示:3种芽孢杆菌单独或组合施用后均可有效抑制黄瓜枯萎病的发生,并显著增加黄瓜植株的生物量,且三菌剂联用双菌剂联用单菌剂施用。在黄瓜幼苗移栽后35 d,与对照组相比,三菌剂联用组黄瓜枯萎病的发病率降低了79.99%;植株干质量提高了6.92倍;植株抗性酶如苯丙氨酸解氨酶、多酚氧化酶、过氧化物酶活性分别提高了60.02%、28.90%和108.60%;根际土壤尖孢镰刀菌数量下降了2个数量级。该防病促生效果可能与这3种芽孢杆菌对病原菌的拮抗作用、溶磷能力以及吲哚乙酸、蛋白酶、几丁质酶和嗜铁素的分泌能力有关。

Control effect of three Bacillus strains on cucumberfusarium wilt and its mechanism

The pot experiment with the soil containing pathogens of Fusarium oxysporum f. sp. was conducted to study the effects of Bacillus megaterium B213,Bacillus polymyxa B207,and Bacillus subtilis B204 alone or in combination on cucumber fusarium wilt and its mechanism. The results showed that the three microbial agents alone or in combination effectively inhibited the occurrence of cucumber fusarium wilt and significantly increased the biomass of cucumber. The effect of the two microbial agents in combination was better than that of single microbial agent. The effect of the three microbial agents in combination was better than that of the two microbial agents. Compared with the control group,the incidence of cucumber fusarium wilt in the three-agent combination group when cucumber seedlings were transplanted 35 days ago reduced by 79.99%; the dry weight of cucumber plants increased by 6.92 times; the activities of plant resistance enzymes including acid lyase,polyphenol oxidase,and peroxidase increased by 60.02%,28.90%,and 108.60% respectively; the number of rhizosphere soil Fusarium oxysporum decreased by 2 orders of magnitude. The effect of disease prevention and growth promoting may be related to the antagonism on the pathogenic bacteria,the ability to dissolve phosphorus,and the secretory ability of indoleacetic acid,protease,chitinase and ferrophilin of these three Bacillus species.