Bacillus velezensis strain MBY2, a potential agent for the management of crown gall disease

Abstract

The reduction of the use chemical pesticides in agriculture is gaining importance as an objective of decision-makers in both politics and economics. Consequently, the development of technically efficient and economically affordable alternatives as, e.g., biological control agents or practices is highly solicited. Crown gall disease of dicotyledonous plants is caused by ubiquitous soil borne pathogenic bacteria of the Agrobacterium tumefaciens species complex, that comprises the species Agrobacterium fabrum and represents a globally relevant plant protection problem. Within the framework of a screening program for bacterial Agrobacterium antagonists a total of 14 strains were isolated from Tunisian soil samples and assayed for antagonistic activity against pathogenic agrobacteria. One particularly promising isolate, termed strain MBY2, was studied more in depth. Using a Multilocus Sequence Analysis (MLSA) approach, the isolate was assigned to the taxonomic species Bacillus velezensis. Strain MBY2 was shown to display antagonistic effects against the pathogenic A. fabrum strain C58 in vitro and to significantly decrease pathogen populations under sterile and non-sterile soil conditions as well as in the rhizosphere of maize and, to a lower extent, tomato plants. Moreover, the ability of B. velezensis MBY2 to reduce C58-induced gall development has been demonstrated in vivo on stems of tomato and almond plants. The present study describes B. velezensis MBY2 as a newly discovered strain holding potential as a biological agent for crown gall disease management.

Bacillus velezensis FX-6 suppresses the infection of Botrytis cinerea and increases the biomass of tomato plants

“…For instance, Chen et al [ 28 ] reported that B . velezensis LM2303 had strong antagonist activity against Fusarium head blight; the study of Ben Gharsa et al [ 29 ] describes that B . velezensis strain MBY2 can be used as a biological agent for crown gall disease management; Chen et al [ 30 ] reported that B .…”

Native Bacillus paralicheniformis isolate as a potential agent for phytopathogenic nematodes control

“…PCR amplification of marker genes was performed using OnePCR ™ Ultra Supermix with Fluorescent Dye (Bio-Helix) according to the methodology described by Ben Gharsa et al (2021) with some modifications. The primer pairs used for the 16S rRNA , gyrA , and groEL genes are detailed in Table 1 .…”

Isolation and Identification of Bacteria of Genus Bacillus from Composting Urban Solid Waste and Palm Forest in Northern Peru

“…Genomic DNA was extracted using a DNA Miniprep Kit (ZymoBIOMICS, California, USA) following the manufacturer’s instructions. The primer combination for the three markers was as follows: for 16S, GM3F (5′-AGAGTTTGATCMTGGC-3′) and GM4R (5′-TACCTTGTTACGACTT-3′) [ 29 ]; for gyr A, 42f (5′-CAGTCAGGAAATGCGTACGTCCTT-3′) and 1066 (5′-CAAGGTAATGCTCCAGGCATTGCT-3′) [ 30 ]; and for rpoB, 2292f (5′-GACGTGGGATGGCTACAACT-3′) and 3354r (5′-ATTGTCGCCTTTAACGATGG-3′) [ 31 ]. Each marker was amplified using polymerase chain reaction (PCR) with MasterMix (Promega, Madison, WI, USA) in the following reaction mixture: 10 ng of DNA and 0.25–0.5 pmol of the forward and reverse primers in a total volume of 10 μL.…”