Effects of Bacillus velezensis strain BAC03 in promoting plant growth

摘要

Bacillus velezensis (formerly referred to as Bacillus amyloliquefaciens) strain BAC03 is a plant growth promoting rhizobacterium. It has shown to be antagonistic against Streptomyces scabies in our previous studies, but its efficacy on plant growth promotion needs to be determined. In this study, BAC03 was tested for potential growth promotion on nine selected types of plants, including beet, carrot, cucumber, pepper, potato, radish, squash, tomato, and turnip, at the concentration of 105 colony forming unit cm (3) potting mix under greenhouse conditions. Results showed that BAC03 increased the growth of some tested plants at various levels in different plant parts. Application of BAC03 at 10 days after planting was associated in radish with the highest biomass gain compared to applications at other stages. Multiple applications of BAC03 giving the same total amount of inoculum resulted in higher weights of radish roots and leaves. That BAC03 produced indole-3-acetic acid and ammonia, as well as showed a 1-aminocyclopropane-1-car boxylate deaminase activity may be related to plant growth promotion. Acetoin and 2,3-butanediol were detected as major components of the volatile released from BAC03 by using gas chromatography-mass spectrometry analysis. (C) 2016 Elsevier Inc. All rights reserved.