Effect of environmental factors and Sclerotium cepivorum isolate on sclerotial degradation and biological control of white rot by Trichoderma

摘要: Laboratory assays demonstrated that two isolates of Trichoderma viride and one isolate pseudokoningii degraded up to 80% sclerotia four Sclerotium cepivorum in a silty clay soil, also 60% three other soil types. Relationships were defined between the degree sclerotial degradation by T. both temperature water potential. Sclerotia 10 25°C at −0·00012 MPa, but there was little activity 5°C or −4 MPa. Degradation S. occurred absence potentials approaching saturation. Experiments using onion seedling bioassays showed efficacy for control white rot same selection soils variable, significant disease overall. The importance environmental factors pathogen relation effective biological is discussed.