Evaluation of biological and chemical treatments for control of gummy stem blight on cucumber plants grown hydroponically in greenhouses

摘要

Four experiments were conducted to evaluate the efficacy of biological and chemical treatments to control gummy stem blight of cucumber caused by Didymella bryoniae (Auersw.) Rehm under greenhouse conditions. The treatments BASF 516, azoxystrobin, and Prestop (biological agent) controlled the disease when applied as preventative sprays on lesions caused by D. bryoniae on cucumbers in three experiments. Treatments with the yeast (Rhodosporidium diobovatum Newell & Hunter), Quadra 137, and Decree reduced lesion lengths compared with the control in one experiment only. No significant differences in lesion lengths were observed between RootShield, calcium nitrate, Quadra 136, SoilGard, Mycostop, and inoculated control in three experiments. Azoxystrobin, BASF 516, and Prestop had significantly less percentage of plants with D. bryoniae infection than treatments with yeast, Quadra 137, Quadra 136, RootShield, SoilGard, Mycostop, Decree, calcium nitrate, and the control. These results suggest the potential of BASF 516, azoxystrobin, and Prestop applied as a preventative treatments to control gummy stem blight on greenhouse cucumbers.