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

Four experiments were conductedto evaluate the efficacy of biological andchemical treatments to control gummy stemblight of cucumber caused by Didymellabryoniae (Auersw.) Rehm under greenhouseconditions. 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 (Rhodosporidiumdiobovatum Newell & Hunter), Quadra 137, andDecree® reduced lesion lengths compared withthe control in one experiment only. Nosignificant differences in lesion lengths wereobserved between RootShield®, calcium nitrate,Quadra 136, SoilGard®, Mycostop®, andinoculated control in three experiments.Azoxystrobin, BASF 516, and Prestop® hadsignificantly less percentage of plants withD. bryoniae infection than treatmentswith yeast, Quadra 137, Quadra 136,RootShield®, SoilGard®, Mycostop®, Decree®,calcium nitrate, and the control. These resultssuggest the potential of BASF 516,azoxystrobin, and Prestop® applied as apreventative treatments to control gummy stemblight on greenhouse cucumbers.