Effect of Chlorothalonil and Famoxadone + Cymoxanil in control of early blight disease of tomato under field conditions

Effect of chlorothalonil (Daconil SC 725) and famoxadone + cymoxanil (Equation Pro WG %52. 5) fungicides in control of Early Blight disease of tomato were evaluated under field conditions. The experiments were carried out in a Randomized Complete Blocks Design (RCB) with eight treatments and four replications during two years in Karaj. Experimental plots inoculated with causal organism at the beginning of flowering stage. Spraying of plots was started by early symptoms seen and continued with 5، 7 and 10 days intervals. Disease Severity Index (DSI) assigned by Foliage Protection Percentage (FPP) with causal agent by using Horsfall and Barratt method، before each spraying، and the later assessing was done 14 days after last spraying. Yield of each plot was measured، and numbers of fruits for each plant were counted. Analysis of variance of two years data، were done at Randomized Complete Blocks Design (RCB) by SAS software، and means were compared with Duncan multiple range test. Area under the Disease Progress Curve (AUDPC) was calculated using five separate disease assessments data، and effects of treatments on disease progress were also studied. The results revealed that there were significant differences between treatments in DSI in all assessments، AUDPC and yield but there was no significant difference between treatments in number of fruits. Also the results for 5th assessment and AUDPC in both study years showed that Daconil SC 725 (3 L/ha) and Equation Pro (450 g/ha) with lowest mean based on DSI were the best treatments to control of Tomato Early blight disease. Daconil SC 725 (3 L/ha) and Equation Pro (450 g/ha) were decreased DSI by 80. 26 and 80. 6 percent in compare to control، respectively. In terms of mean fruit weight، Equation Pro (450 g/ha) and Daconil SC 725 (3 L/ha) were increased yield 65. 03 and 64. 17 percent in compare to control، respectively، and were the best treatments.