Chemical control of tomato early blight caused by Alternaria solani using certain fungicides and chemical inducers

Eight isolates were isolated from tomato plants identified as Alternaria solani were involved in pathogenicity tests which resulted in definite symptoms of early blight disease of tomatoes. Four antioxidant compounds were tested against both aggressive and non-aggressive isolates, salicylic acid showed high efficacy in reducing growth of A. solani even as linear growth in vitro or as disease severity in vivo followed by citric acid and catechol respectively, while, ascorbic acid showed lowest effect. On the other hand, laboratory and greenhouse experiments were carried out to evaluated four fungicides for their inhibitory effect on the growth of A. solani aggressive and non-aggressive isolates. Bellis fungicide recorded the best result in controlling the disease either in vitro or in vivo as compared to other fungicides and control. Amistar-top and luna experience exhibited intermediate effect on the fungus isolate, and the lest order was achieved by folio- gold fungicide. In general, fungicides were more effective in controlling the disease than the tested antioxidants but, environmental pollution and hazardous effect, on human health must be considered