中文摘要：

实验采用平板对峙法，从黄萎病发生严重的棉田中的健康植株根际土壤中分离筛选到11株对棉花黄萎病致病菌Verticillium dahliaeKleb（Vd）具有拮抗效果的菌株，抑菌率在51．8％和87．4％之间，经培养滤液抑菌率试验复筛，选择抑菌效果较好的3株菌株进行盆栽试验。结果表明：在施用拮抗菌摇床培养液（VS）、有机肥（VF）和两者结合（VFS）的3个处理中，VFS效果最显著，防病率达57％，植株生理性状显著改善，根际可培养微生物数量发生显著变化，细菌数量增加7．3～13．4倍、放线菌数量增加3．2～5．9倍，病原菌微菌核数量下降34％。结合生理生化和16SrDNA技术鉴定，初步确定供试的2株菌为死谷芽孢杆菌（Bacillus vallismortis），1株菌为枯草芽孢杆菌（Bacillus subtilis）。研究表明拮抗菌与有机肥共同施用不仅可以起到防病的作用，而且可以使棉花连作土壤微生物区系向健康、合理的方向发展。本文首次报道了死谷芽孢杆菌对棉花黄萎病有抑制作用。

英文摘要：

In an experiment using the flat-stand method, 11 strains of bacteria antagonistic against VerticiUium dahliae Kleb （Vd） were isolated from healthy cotton plants growing in cotton fields seriously infected with verticillium wilt. Their verticillium inhabiting rates ranged from 70% to 87.4%. Cotton Verticillium wilt disease was effectively suppressed by 57% over the control by application of a mixture of the antagonistic bacteria along with organic fertilizer. Microbial communities were significantly changed in cotton rhizospheric soils in Treatment VS （application of mixed antagonistic strain solution）, Treatment VF （organic manure）, and Treatment VFS （strain solution plus organic manure）, among which Treatment VFS was the highest in disease inhabiting rate, reaching 57%. Significant increase in population of bac- teria and actinomyces and decrease in population of pathogen microsclerotia were found in these treatments, as compared with that in the control. Based on the physiological and biochemical determination and the 16S rDNA sequence analysis, HJ-5 and DF-15 strains were identified as Bacillus vallismortis, while DF-14 strain as Bacillus subtilis. This is the first paper that reports Bacillus vallismortis is antibiotic against Verticillium dahliae.