Seed biopriming with indigenous endophytic bacteria isolated from Wakatobi rocky soil to promote the growth of onion (Allium ascalonicum L.)

Abstract

The realization of sustainable agriculture requires continuous research which can reduce the use of chemical fertilizers. This research was carry out to obtain the potential indigenous endophytic bacteria isolated from onion planted on rock soil of Wakatobi district in Southeast Sulawesi. The study conducted using a completely randomized design (CRD) consisting of 9 isolates. Germination was recorded daily until 14 days. At the same time, isolates evaluated for their ability to solubilize phosphate, fix N and synthesize IAA. Results showed that the seed treatments using endophytic bacteria significantly increased viability onion seeds, in term of germination increases in germination percentage. Almost all endophytic bacteria isolate tested were able to solubilize phosphate, fix N and synthesize IAA. From this study, Ke03 isolates showed the best performance and were able to increase germination percentage, root length and number of onion roots reaching 145%, 46% and 78% respectively, as compared to controls. The ability of Ke03 isolates to increase onion germination correlated with the ability of this isolate to synthesize IAA (80.33 ppm). Further research is needed to evaluate whether this isolate is effective in increasing the growth and yield of onions in the field.