Effect of pesticides on the growth and secreted chymotrypsin-like activity of a biocontrol strain of bacillus amyloliquefaciens

Absztrakt

Biocontrol is an alternative approach to reduce the harmful effects of pathogen species in the agriculture.
Pesticide-tolerant biocontrol agents are preferred in the integrated pest management because they can be
applied together with different fungicides, herbicides and insecticides. A potent biocontrol agent, Bacillus
amyloliquefaciens SZMC 22206 strain was isolated and studied previously. It was revealed, that the
extracellular chymotrypsin-like protease and fengycin secretion of the strain resulted its antagonistic effect.
The aim of our present study was to analyse the effect of different pesticides on the growth and activity of the
extracellular chymotrypsin-like proteases of this Bacillus strain. The tested pesticides were a fungicide
(carbendazim), and three frequently used herbicides (linuron, chlortoluron and 2,4-dichlorophenoxyacetic
acid). The tested Bacillus strain was able to grow in the presence of the pesticides, but the activities of the
extracellular chymotrypsin-like proteases were significantly reduced in some cases.