Bacillus strains with potential for growth promotion and control of white mold in soybean

• Published in: Biológia Vol. 77; no. 11; pp. 3305 - 3317
• Main Authors: Duré, Laís Mayara Melo, Galeano, Rodrigo Mattos Silva, Viana, Thianny Fernanda Carrelo, Roque, Cassiano Garcia, Matias, Rosemary, Paggi, Gecele Matos, Corrêa, Bianca Obes, da Silva Brasil, Marivaine
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01-11-2022; Springer Nature B.V
• Subjects: Antiinfectives and antibacterials; Bacillus; Biological control; Biomedical and Life Sciences; Cell Biology; Cultivars; Disease control; Fungi; Genes; Greenhouses; In vitro methods and tests; In vivo methods and tests; Inoculation; Life Sciences; Microbiology; Mold; Original Article; Phytopathogenic fungi; Plant growth; Plant Sciences; Soybeans; Strains (organisms); White mold; Zoology; Microbiolization; Inoculation; Rhizobacteria; Antibiosis; Biocontrol
• ISSN: 1336-9563; 0006-3088; 1336-9563
• DOI: 10.1007/s11756-022-01186-5

Plant growth-promoting rhizobacteria (PGPR) are known to stimulate the biocontrol of phytopathogenic bacteria and fungi, induce plant growth, and increase the yield of important economic crops. In this study, we evaluated in vivo, the ability of
Bacillus
strains to control soybean white mold disease and promote the growth of soybean plants under greenhouse conditions. Initially, 27
Bacillus
strains were analyzed by PCR for the presence of genes encoding antimicrobial molecules, followed by in vitro tests of the positive strains against four phytopathogenic fungi,
Sclerotinia sclerotiorum
,
Macrophomina phaseolina
,
Rhizoctonia solani
, and
Colletotrichum truncatum
. The bacterial strains that returned positive results for antimicrobial genes were evaluated in vivo for their growth promoting capacity in soybean cultivars Potencia RR and M6210 IPRO, and white mold control in soybean plants. The results showed that eight strains presented the genes
bamD
,
ituD
, and
fenF
, while the
bacAB
gene was observed in 16 of all tested
Bacillus
strains. The greenhouse experiment showed that the inoculation of the strain VBN02 was the best treatment for increasing fresh shoot biomass of the soybean M6210 IPRO and Potencia RR cultivar in the single inoculation in relation to the control (111.9% and 103.57%, respectively). Co-inoculation of soybean inoculant and VBE01 was the superior treatment for increasing fresh shoot and root mass in both the cultivars. Two other strains, VBE05 and VBE01, reduced the disease progression of white mold by 39.1% and 37.5%, respectively. In conclusion, our results showed that the
Bacillus
strains have potential for biocontrol of white mold and for promoting the growth of soybean plants.