Optimum cultivation conditions for mass production of antagonistic bacterium Pseudomonas azotoformans HC5 effective in antagonistic of brown blotch disease caused by Pseudomonas tolaasii

This study was conducted to investigate optimum conditions for mass production of antagonistic microbes Pseudomonas azotoformans HC5.P. azotoformans HC5 is a potent biological control agent to control brown blotch disease caused by Pseudomonas tolaasii.This markedly showed the antagonistic activity against P. tolaasii, the most destructive pathogen of cultivated mushrooms.To define the optimum conditions for the mass production of the P. azotoformans HC5, we have investigated optimum culture conditions and effects of various nutrient source on the bacterial growth.The optimum initial pH and temperature were determined as pH 6.0 and 15 o C, respectively.The optimal concentration of medium elements for the growth of pathogen inhibitor bacterium was determined as follows: 0.6% adonitol, 1.5% yeast extract, 0.8% NH 4 H 2 PO 4 , 5mM MgSO 4 , and 0.2% asparagine.