(1973)International Symposium on Factors Determining the Behavior of Plant Pathogens in Soil International Symposium on Factors Determining the Behavior of Plant Pathogens in Soil International Symposium on Factors Determining the Behavior of Plant Pathogens in Soil,Berkeley,Cali International Symposium on Factors Determining the Behavior of Plant Pathogens in Soil,Berkeley,Calif