The Effects of Fungicides on Fusarium Oxysporum F. SP. Lycopersici Associated with Fusarium Wilt of Tomato

Abstract

Tomato fusarium wilt is considered as one of the most important diseases of tomato both in field and greenhouse - grown tomatoes worldwide. In presented research, six fungicides; benomyl, carbendazim, prochloraz, fludioxonil, bromuconazole and azoxys- trobin, were evaluated for their efficacy against the disease casual agent Fusarium oxysporum f. sp. lycopersici in vitro and in vivo. Seven different concentration (0.0001, 0.001, 0.01, 0.1, 1, 10, 100 µg/ml) were used for assessment of their inhibitory activities against the patho- gen through mycelial growth inhibition on potato media. Four concentrations of above mentioned fungicides (0.1, 1. 10 and 100 µg/ml) were tested for controlling Fusarium wilt on tomato plants in glasshouse. Fungal radial growth was measured and median effective con- centration (EC 50 ) values (µg/ml) determined. The result of glasshouse tests revealed a different degree of efficacy of all tested fungicides in reducing disease infestation. Prochloraz and bromuconazole were the most effective fungicides against the pathogen both in vitro and in vivo, followed by benomyl and carbendazim. All other fungicides were less effective. Conserning the application date of fungicides it was shown that they were less effective when applied 7 days after tomato plant infection, compared with 1 day prior infection. No phytotoxic symptoms were observed after the application of prochloraz, bromuconazol and benomyl when used at recommended doses, especially on seedlings. However both fungicides fludioxonil and bromuconazole were shown to be phototoxic to tomato seedlings.