The growth response of the biocontrol agent Pantoea agglomerans 2066-7 to change in water activity (aw), temperature, and pH was determined in vitro in basic medium. The minimum temperature at which 2066-7 was able to grow was 7°C, and the growth of 2066-7 did not change at varying pH levels (4–10.34). The best growth was obtained at a water activity of 0.98 in all media modified with the four solutes (glucose, glycerol, NaCl and polyethylene glycol). The solute used to reduce water activity had a great influence on bacterial growth, especially at unfavorable conditions (low temperature). This study has defined the range of environmental conditions (aw, pH, and temperature) over which the bacteria may be developed for biological control of plant diseases.
Pantoea agglomerans, ecology, water activity and plant diseases