| Summary: | 碩士 === 國立高雄師範大學 === 生物科技系 === 99 === The research is focus on 14 bacteria strain which were isolated from mud. In this study the bacteria were identified by physiological character and polymerase chain reaction (PCR) though amplification and sequencing of the 16S rRNA gene, 16S-23S internal transcribed space (ITS) region and specific gene. Bacillus amyloliquefacien (A1) and Pseudomonas sp. (A6) were selected to further analyze and evaluate. The enzymes activities, protease、β-glucanase and chitinase, were highest at one day after incubation of A1 and A6. The highest inhibition activity of A1 was obtained for against Ralstonia solanacearum with 1.2 cm radius of inhibition circle. Confrontational inhibition、oppressed inhibition and supernatant inhibition were used to test inhibition activities to fungi. The result showed that A1 were able to inhibit many plant pathogenic fungi, especially Botryodiplodia theobromae Pat. and Alternaria brassicae (BERK) Sacc. In chemical pesticides test, the effectiveness of fungicides indicated that poly-dithiocarbamate had worst effect to A1, the survival rate was below 30%. The effectiveness of bactericides indicated that copper compounds and antibiotic pesticide had worst effect to A1, the survival rate below 60%. The effectiveness of insecticides indicated that pyridine organothiophosphate、organophosphorous and aliphatic amide organothiophosphate had worst effect to A1, the survival rate below 70%. The effectiveness of most weedicides had worst effect to A1, and surfactant had no effect to A1. The highest inhibition activity of A6 was obtained for against Ralstonia solanacearum with 0.8 cm radius of inhibition circle. In addition, A6 were not able to infect 9 species crops in Cucurbitaceae、Solanaceae、Brassicaceae and Poaceae. In bioassay A6 was able to inhibit the infection of Ralstonia solanacearum in tomato crop. Finally, in PGPR test, the result of One-way ANOVA analysis for cucumber treated with A6 had statistically significant difference at leaves numbers、maximum leaf and root dry weight, and the result of One-way ANOVA analysis for tomato treated with A6 also had statistically significant difference at plant height and branch numbers.
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