Evaluation of the inhibitory effect of some fungicides on Fusarium wilt disease in greenhouse cucumber

Fusarium oxysporum f.sp. cucumerinum, the causal agent of Fusarium wilt is one of the most important diseases, which results in extensive damages to greenhouse cucumber every year. This pathogen is able to infect plants at all growth stages, decreases plant quality, and subsequently leads to plant death. This investigation was conducted to propose an appropriate fungicide in an efficient dosage for managing cucumber Fusarium wilt. The efficiency of different dosages of biological, organic and chemical fungicides on fungal growth inhibition was evaluated in vitro. These fungicides were included Amistar Xtra (0.75, 1 and 1.25 l/hectare), Tachigaren (2, 2.5 and 3 l/hectare), Uniform (1, 1.5 and 2 l/hectare), Lamardor (1.5, 2 and 2.5 l/hectare), Thiophanate-methyl (1, 1.5 and 2 kg/ hectare), Fusar (1.5, 2 and 2.5 l/hectare) and Trianum P. The EC50 of all fungicides calculated first, then varying doses of fungicides were prepared and added to PDA culture. A 0.5-cm diameter PDA plug containing mycelia of the fungus was placed in the center of each plate. After a week of incubation at 26oC, the fungal growth in different treatments was evaluated and compared. Theresults showed that Amistar extra (1.25 l/hectare) had the most efficient inhibitory effect (more than 98%) on fungus growth in vitro. All experiences have been done in 4 replications. Statistical analysis was performed using SAS ver.9.2 and Duncan test was used to show significant differences among treatments. The efficient treatments thathad the highest fungal growth inhibitory effects will select to apply in greenhouse condition