A multi-criteria approach for the selection of efficient biocontrol agents against Botrytis cinerea on tomato in Algeria

In order to find biocontrol agents that are both efficient against Botrytis cinerea Pers. and adapted to tomato growing conditions in Algeria, 121 bacterial strains were collected from tomato plants and nearby soils in two Bejaia greenhouses. A total of 37 strains were selected based on their ability to grow on agar medium and on their different level of B. cinerea mycelial growth inhibition in dual-culture tests. These strains were identified at the species level and those that corresponded to potential pathogens for humans or mammals were discarded. Among the remaining 25 candidates, three strains were selected among the Pseudomonas genus for their significant protective efficacy against B. cinerea on tomato, their ability to grow at 15–25 °C and their inability to grow at 37 °C. These three strains significantly reduced the development of necrotic lesion and the sporulation of B. cinerea in a dose-dependent manner. This study constitutes a first step towards the biological control of B. cinerea in tomato greenhouses in Algeria.