Five Trichoderma isolates and two bacterial bioagents, six different plant extracts - compared to five commercial fungicides; were tested individually and in combinations in in vitro and in vivo against white rot disease of cucumber caused by Sclerotinia sclerotiorum. All tested bioagents, plant extracts, and fungicides caused
significant growth reduction of S. sclerotiorum. Trichoderma hamatum caused the highest reduction followed by T. viride and T. harzianum. Bacillus subtilis was better than Pseudomonas fluorescens in reducing growth of S. sclerotiorum, meanwhile, all
tested biocides reduced the mycelial growth and sclerotia formation at their highest concentrations. Also, both linear growth and production of sclerotia of S. sclerotiorum were significantly reduced by all tested plant extracts compared to control. Moreover,
all fungicides caused complete inhibition of growth and sclerotial formation of S. sclerotiorum. Under greenhouse conditions, T. album and T. harzianum-2 were the best effective treatments for disease management followed by B. subtilis and P. fluorescens. Neem was the best effective plant extract as it reduced disease incidence and severity and it gave increased fresh and dry weight of shoot and root followed by onion and lemongrass. Moreover, the highest reductions of disease incidence and severity were obtained in case of Bellis and Onest 70%. While, all the tested commercial biocides significantly reduced white rot disease incidence and severity, as well as increased the fresh and dry weight of shoot and root. Applying variety of combinations of the previous tested management methods as integrated management
approaches resulted in the significance of all tested combinations in the reduction of
white rot disease incidence and severity, as well as the improvement of some growth characters |
