In vitro Evaluation of Certain Fungicides Against Botrytis cinerea Isolates the Causal Pathogen of Gray Mold Disease on Tomato

Efficiency of fungicides; Teldor 50%SC, Nowton 50% SC, Toledo 43% EC, Kenzo 50% WG and Suntop El-nasr 70% WP against tomato gray mold disease was conducted In vitro tests. The sensitivity of Botrytis cinerea isolates to tested fungicides differed significantly according to their aggressiveness. The lowest pathogenicity isolate BcI-3 ranked as the most susceptible isolate, while the highest pathogenicity isolate BcB-2 was the least susceptible isolate to the tested fungicides. Medium effective concentrations (EC50) of the tested fungicides indicated that Teldor 50%SC was the superior fungicides against mycelial growth of the all tested isolates, while Suntop El-nasr 70% WP was the inferior one. The EC50 values of the tested fungicides for mycelial growth of the least aggressive isolate (BcI-3) were less than that of the other tested isolates. Under greenhouse condition, all tested fungicides were control gray mold disease on tomato. Data revealed that when tested fungicides treated as curative or protective, were effective in reducing the disease severity of gray mold produced from the most and least aggressive isolates. Tested fungicides Teldor 50% SC and Toledo 43% EC gave excellent control of gray mold disease when applied as protective or curative. All tested fungicides, expect Suntop El-nasr 70% WP, were effective in controlling gray mold as curative treatement.