| Wheat sharp eye-spot, caused by Rhizoctonia cerealis, is an important soil-borne wheat disease in the middle and lower valley of Yangtze River. A large number of studies have shown that Pseudomonas spp. is an important inhabited bacterium in wheat rhizosphere, and it has inbibitory effect on many soilbrone plant pahogens.Thitry-seven strains isolated from wheat rhizosphere in Jiangyan city of Jiangsu Province were used in this experiment. In vitro tests revealed that 10 (T4,T8,T19,T22,T23,Ct10,Ct14,Ct22,Ct26,Ct28) bacterial strains have obvious antagonistic activities against Rhizoctonia cerealis . These 10 strains were identified as fluorscenct Pseudomonas based on molecular systematic analysis and physiological and biochemical tests, and in which T4,T8,T19,T22,Ct10,Ct22,Ct28,Ct14 were determined as Pseudomonas migulae, T23 was P. poae and Ct26 was P. putida.The main reason of fluorscenct Pseudomonas can suppress many soilbrone plant diseases is that they can produce multiple antibiotics including pyoluteorin, pyrrolnitrin, 2,4-diacetylphloroglucinol, and phenoxazine. The antifungal metabolites among these 10 strains were analysed. The results indicated that all 10 strains produced siderophore and proteinase, but none of them produced Pyrrolnitrin and Pyoluteorin. The strain of T4,T22,T23,Ct26 and Ct28 produced 2,4-DAPG, T4,T8 and Ct28 produced PCA, T22and T23 produced HCN, and there have 6 strains produced chitinase except T8,T23,Ct10,Ct26.It is valuable to determine the control efficiency of fluorscenct Pseudomonas to wheat sharp eyespot and the colonization ability of antagonistic bacteria in the rhizosphere of wheat. The biocontrol assays carried out at seedling stage in greenhouse. The results demonstrated that all of the 10 strains can decrease disease index of wheat eyespot. Among them, the Ct26 was most effective. The studying on colonization ability of these bacteria revealed that all of strains can colonize in wheat rhizosphere for 45 days or long.
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