Effect of pH, temperature and water activity on the inhibition of Botrytis cinerea by Bacillus amyloliquefaciens isolates

Abstract

A total of 321 bacterial strains were isolated from the rhizosphere of healthy strawberry (Fragaria X ananassa Duch.) plants harvested from different places in Zlaoula area (Larache, Morocco). They were screened by dual testing for in vitro antagonism towards Botrytis cinerea (Bt7). Nine antagonistic strains were retained. Their effectiveness was evaluated according to temperature (5 to 30°C), pH (4 to 10) and water activity (aw, 0.80 to 1). Low values of water activity and acid pH were unfavourable for the growth inhibition. All the isolates were identified to belong to Bacillus amyloliquefaciens.

Key words: Antifungic activity, water activity, Bacillus amyloliquefaciens, Botrytis cinerea, pH, temperature.