Indonesian

Abstract

Saputra R, Arwiyanto T, Wibowo A. 2015. Antagonistic activity assay of some isolates of Bacillus spp. against Bacterial Wilt Diseases (Ralstonia solanacearum) in some varieties of tomato and it’s identification. Pros Sem Nas Masy Biodiv Indon 1: 1116-1122. Ralstonia solanacearum is an important bacterial plant pathogen that frequently attacks in tomato plants and causes wilt disease. A great number effort has practiced minimizing this disease such as farming practices, the use of chemical pesticides and the development of resistant varieties, however, all showed limited success. Due to the limited effectiveness of some of these controls, yet bacterial wilt disease remains a serious problem economically. Therefore, biological control is still a great concern today. Of the many antagonistic bacteria, Bacillus spp. and Pseudomonas spp. are the most widely used in the biological control of plant diseases. The purposes of this study were to identify Bacillus spp. and investigate the capability of Bacillus isolates to suppress the development of bacterial wilt in tomato plants. The research was conducted at the Laboratory of Plant Bacteriology and greenhouse, Department of Plant Pest and Diseases, Faculty of Agriculture, UGM. Bacillus isolates were isolated from the rhizosphere of tomato plants. Based on the results of the study, six isolates of Bacillus showed diverse capabilities in suppressing the development of bacterial wilt disease, but Bacillus sp. isolate Ba-1 demonstrated the ability tends to be better than the other isolates. The biochemical identification results revealed that six isolates of Bacillus have similar properties. Homology of Bacillus sp. isolate Ba-1 by 16S rRNA gene of BLAST result showed this bacterium is closely related with Bacillus licheniformis strain DSM 13T (NR 118996) as the homology between them was 99%.