%0 Journal Article %A YUAN Yuan %A ZHANG Hong %A SU Daolahu %A ZHENG Rong %A SHI Lingling %A WU Huiling %T Biocontrol Effect of Streptomyces sp. S-101 against Cucumber Wilt %D 2019 %R 10.16409/j.cnki.2095-039x.2019.05.025 %J Chinese Journal of Biological Control %P 813-820 %V 35 %N 5 %X In order to obtain efficient biocontrol bacteria against cucumber wilt, the microorganisms in the vegetation root soil near Qinghai Lake were isolated and screened. The activity of antagonistic bacteria and its control effect on cucumber wilt disease were determined. Streptomyces sp. strain S-101 was isolated and screened by plate confrontation method and its antagonism against different plant pathogens was investigated. The results showed that the strain had good effect on several pathogenic fungi, among which the inhibition rates on Fusarium oxysporum f. sp. cucumebrium and Colletotrichum gloeosporioides were 53.3% and 45.5%, respectively. Based on morphological observation and 16S rDNA sequence analysis, the strain S-101 was preliminarily identified as Streptomyces luridus. Pot experiment showed that the fermentation broth displayed significant control effect on cucumber wilt with the efficacy of 57.11%.The strain S-101-GFP was able to colonize at the roots of cucumber. With the increase of colonization days, the number of labeled bacteria decreased from 1×108 cfu/g to 1×106 cfu/g. The number of colonies dropped rapidly in 0-14 days, fell slowly in 21-28 days and maintained a stable amount in 28-35 days at 1×106 cfu/g. Therefore, strain S-101 is a potential biocontrol strain against cucumber wilt, and has the application value of being developed into microbial fungicide. %U http://www.zgswfz.com.cn/EN/10.16409/j.cnki.2095-039x.2019.05.025