Summary: | 碩士 === 國立中興大學 === 植物病理學系 === 89 === 柒、英文摘要
A total of one hundred and seventy five strains of yellow-pigmented bacteria were isolated from twenty-two crop species and four weed plant species at different localities in Taiwan. Among them, 106 strains were Gram negative, and the other 69 strains were Gram positive. Based on Biolog identification system, 61 strains of Gram negative bacteria were identified as species in Actinobacillus, Burkholderia, Chryseobacterium, Enterobacter, Erwinia, Flavimonas, Haemophilus, Pantoea, Pseudomonas, Sphingomonas, Stenotrophomonas, and Xanthomonas. Thirteen strains of Gram positive bacteria were identified as species in Corynebacterium, Curtobacterium, Kytococcus, Microbacterium, Micrococcus, and Staphylococcus. There were 17 strains of Pantoea agglomerans isolated in this study. Utilization of carbon sources by these 17 strains of P. agglomerans were examined with the Biolog GN2 Microplate. The results revealed that among the 95 carbon sources tested, all these 17 strains could utilize 40 carbon sources; and varied in the utilization of 37 carbon sources; in addition, they all did not utilize the other 18 carbon sources. When DNAs from P. agglomerans strains isolated in this study were used as templates, no specific DNA fragment was amplified by PCR with primer pairs etzⅠL/etzⅠR, which are specific to cytokinin biosynthesis gene (etz) of P. agglomerans pv. gypsophilae. Most strains of P. agglomerans isolated showed inhibitory effect on the growth of phytopathogenic bacteria tested. The relative disease index of bacterial spot on leaves of sweet pepper co-inoculated with cell suspensions of X. axonopodis pv. vesicatoria XVT40 and P. agglomerans Yh93 or Yh95 was significantly lower than that of the control plants on which the plants were inoculated with X. axonopodis pv. vesicatoria XVT40 only.
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