Influence of agro‐environmental pollutants on a biocontrol strain of Bacillus velezensis

Abstract

Metal- and pesticide-tolerant biocontrol agents are preferred in integrated pest management, as such strains can be applied in combination with different pesticides. The Bacillus velezensis strain SZMC 6161J proved to be sensitive to copper, nickel, zinc, and cadmium, while manganese elevated its growth. At concentrations higher than 1 mmol L , zinc and iron inhibited the chymotrypsin-like activity of this strain. In addition, trypsin-like protease and palmitoyl esterase activities were insensitive to all tested heavy metals in the applied concentration range. We studied the effects of some widely used herbicides and fungicides on the growth of this strain. The presence of sulfonylurea herbicides, like bensulfuron-methyl, cinosulfuron, chlorsulfuron, ethoxysulfuron, triasulfuron, and primisulfuron-methyl strongly inhibited the biomass production of the strain even at the concentration of 6.25 mg L . Glyphosate also inhibited the growth above 30 mg L . Similarly, contact fungicides like captan, maneb, mancozeb, and thiram resulted in total inhibition at the concentration as low as 6.25 mg L . Interestingly, the sterol-biosynthesis-inhibiting fungicides imazalil, fenarimol, penconazole, and tebuconazole also proved to be potent inhibitors. Heavy metal- and fungicide-tolerant strains were isolated from the parental strain and their antagonistic abilities were evaluated. There was no substantial difference between the antagonism capability of wild-type strain and the resistant mutants.

Expression regulation of chitin‐binding protein and metal‐binding peptide in new Bacillus velezensis: MALDI‐TOF MS/MS analysis

“…Also, it has been able to tolerate some metals with high concentrations, and its growth inhibited at 8 mM lead(II) nitrate, 7 mM calcium chloride dihydrate, 5 mM potassium dichromate(VI), 3 mM nickel(II) chloride hexahydrate, and manganese(II) chloride and 2 mM copper(II) sulfate pentahydrate, while in another study, B. velezensis SZMC 6161J was isolated from the rhizosphere of a tomato plant and could grow in the presence of 0.1 mM copper, manganese, nickel, and iron. B. velezensis SZMC 6161J was sensitive to cadmium and zinc [34] as our isolate could not grow on cadmium nitrate tetrahydrate and mercury(II) chloride, and had low resistance to cobalt(II) chloride hexahydrate and zinc sulfate heptahydrate.…”

Perspectives on the microorganism of extreme environments and their applications

“…Thermophiles like Bacillus sp. have applications in many industries, e.g., aliphatic and aromatic hydrocarbons and synthetic dyes can be removed by thermophiles ( Vörös et al., al.,2019 ; Orellana et al., 2018 ). Petroleum industries and oil spills can result in contamination of soil and groundwater as they release harmful substances such as polycyclic aromatic hydrocarbons and long-chain alkanes (C10 to C32) which can be decontaminated by certain strains of extremophiles, namely Bacillus, Thermus, and Geobacillus ( Sun et al., 2015 ; Jeong and Choi, 2020 ).…”

Screening for production of amylase and protease by locally-isolated Bacillus spp. from soil collected in Taguig City and Clark Freeport Zone, Philippines

“…Its presence in the CRK1 sample may be attributed to its potential tolerance to the edaphic conditions. A paper has previously reported a heavy metal-tolerant protease from a B. velezensis strain isolated from the rhizosphere of tomato plant 27 .…”