Diversity of Bacillus spp. from soybean phyllosphere as potential antagonist agents for Xanthomonas axonopodis pv. glycines causal of pustule disease

Pustule disease caused by Xanthomonas axonopodis pv. glycines (Xag) is an important disease in soybean. Bacteria from soybean phyllosphere is one of the potential biological agents against this disease. This is because the microorganisms have similarity. This study aimed to determine the diversity and species of bacteria from the soybean phyllosphere that have potential as biological agents. The research was carried out by morphological observation, physiological-biochemical testing, and molecularly with BOX AIR primer. Molecular identification was carried out by amplifying the 16S-rRNA gene with 27F and 1492R primers. The results showed that 11 isolates could inhibit Xag in vitro which showed morphological, biochemical, and molecular diversity. These bacteria were identified as Bacillus spp. which consisted of 4 groups, namely Bacillus siamensis, B. subtilis. B. amyloliquifaction and B. velezensis. The diversity of phyllosphere bacteria allows them to be used as biological agents because they do not inhibit each other and have diverse living abilities in various environmental conditions. © 2021, Society for Indonesian Biodiversity. All rights reserved.