Abbo Azza Siddig, Idris Mohamed Osman, ElBalla Mustafa Ali
The effect of tomato variety (open-pollinated and hybrid), nitrogen form (urea and ammonium nitrate) and the application time of the fungicide Ridomil Gold® MZ 68% on early blight disease of tomato was evaluated. A field trial was conducted for three consecutive growing seasons (2006/07, 2007/08 and 2008/09). In the growing seasons, early blight symptoms showed up naturally 12 weeks after sowing. The application of the fungicide at the onset of the disease significantly (P ≤ 0.05) reduced disease incidence and increased tomato yield. Regarding disease incidence; the combination of the hybrid variety (Star 9008), use of ammonium nitrate fertilizer as a source of nitrogen and application of Ridomil Gold at the onset of the disease was significantly (P ≤ 0.05) superior to all other combinations included in the experiment.