NEW WAYS FOR CONTROLLING ONION WHITE ROT DISEASE (Sclerotium ceviporum) IN NORTH EGYPT

Sclerotium cepivorum, is worldwide destructive soil borne fungal pathogen and has been reported attacking onion and other Allium species causing considerable damage to the host under congenial environments in Egypt and other regions. Recently, this species was isolated from North Egypt after long settlement in south Egypt. Many attempts were used to control onion white rot disease caused by this pathogen. In the present study three fungicides viz. procimidone (sumisclex?25), vinclozolin (ronilan) and tolclofos-methyl (rizolex) were used against Sclerotium cepivorum and compared with a range of non chemical treatments including five antagonistic fungi, two antagonistic bacteria, two essential oils and fine red onion waste (ROW) in naturally infested area to evaluate their effects on the incidence and severity of onion white rot disease under field conditions. Among all fungicides tested, it was found that sumisclex?25 was the best chemical treatment giving 14.81% reduction in disease incidence and 13.38% severity. While, Gliocladium virens achieved the best results of reducing disease incidence giving 8.89% and disease severity by 8.38%. On the other hand, Pseudomonas fluorescens and Bacillus subtilis reduced disease incidence, giving 21.48 and 22.96%, respectively and high reduction in disease severity by 19.01 and 21.23% respectively. Among all tested essential oils, cinnamon oil considered the best treatment giving 32.59% disease incidence and 28.88% severity. While, ROW was the best treatment reducing the disease incidence, giving 8.15% disease severity.see more