Stepwise-Selected Bacillus amyloliquefaciens and B. subtilis Strains from Composted Aromatic Plant Waste Able to Control Soil-Borne Diseases

Abstract

In the present study, 133 bacterial isolates from 11 composted aromatic plant wastes were selected for their ability to inhibit the mycelial growth of the soil-borne phytopathogenic fungi Sclerotinia minor and Rhizoctonia solani. Successively, a subset of 35 from them were further characterized for their ability to control, in vivo, rocket damping-off caused by the two fungi. Moreover, the isolates were characterized for morphology of the colonies, Gram reaction, siderophore production, P-solubilization and for the presence of antimicrobial lipopeptide genes in the genome. The screening for the in vitro antagonisms showed a mycelial growth reduction ranging between 31.7% and 56.1% for R. solani and 34.4% and 59.4% for S. minor. All the isolates were not able to produce siderophores and some of them were able to solubilize P. The isolates contained two or more of the five lipoproteins coding genes investigated in this study. The most promising isolates were identified at species level by 16S-rRNA partial gene sequence analysis and were grouped in two main clusters related to Bacillus subtilis and Bacillus amyloliquefaciens reference strains. Results indicated that Bacillus isolates from compost are good candidates for application in the biocontrol of cultivated plants.

Characterization of Soil Bacteria with Potential to Degrade Benzoate and Antagonistic to Fungal and Bacterial Phytopathogens

“…None of the strains inhibited the growth of Pantoea agglomerans ATCC 27155TM (formerly Erwinia herbicola ATCC 27155). Bacillus subtilis and B. amyloliquefaciens were among 133 bacterial strains from 11 composted aromatic plant wastes isolated for their ability to inhibit the growth of the mycelium of soil phytopathogenic fungi Sclerotinia minor and Rhizoctonia solani [ 38 ]. Gram-positive bacteria Bacillus spp.…”

Effects of Organic Additives on Chemical, Microbiological and Plant Pathogen Suppressive Properties of Aerated Municipal Waste Compost Teas

“…Actually, plate counts retrieved microbial populations, such as Pseudomonas spp. and Bacillus spp., associated to the biological control of plant pathogens [43,44]. As expected, additives modulated both the structure and composition of CT communities: molasses stimulated microbial shifts more than whey, likely due to sugar content.…”

GROWTH PROMOTION OF GENETICALLY IMPROVED Pinus taeda SEEDLINGS BY INOCULATION WITH SPECIES OF Bacillus.

“…Overall, Bacillus species are fundamentally known to promote plant growth by production of biofilms and action against root pathogens (Chen et al, 2016;Altaf et al, 2017;Zaccardelli et al, 2020). However, a broader range of plant growth-promoting mechanisms has been suggested, especially, for B. amyloliquefaciens.…”