Onion white rot (OWR) is a serious disease of Allium spp. caused by the sclerotium-forming fungus Sclerotium cepivorum. In this study, the efficacy of soil amendment with vegetarian or animal manure compost and mixed of them with or without adding bioagents i.e. T. harzianum and P. fluorescens compared with Folicur fungicide under greenhouse and field conditions were evaluated. Dipping onion transplants in T. harzianum or P. fluorescens before transplanted in amendment soil with vegetarian compost at the rate of 10 and 20% reduced the percentage of the OWR incidence and increased both bulbs fresh and dry weight more than animal and mixed composts under greenhouse conditions. The combination between vegetarian compost (10%) and dipping treatment of either T. harzianum or P. fluorescens were the most suppressive in this regard. Under field conditions combining T. harzianum, P. fluorescens and Folicur with or without compost enhanced control of white rot disease and bulbs yield of onion compared with using biological agent alone. The combination of T. harzianum, P. fluorescens and/or Folicur fungicide alone or combined with vegetarian compost applied as soil amendment or foliar spraying of compost extract (10%) twice for two months from planting exhibited a decrease on white rot disease incidence and increased the bulbs yield in Gharbiya and Qalubiya locations. |
