Rapid Quantification of Fungicide Effectiveness on Inhibiting Wheat Stripe Rust Pathogen ( f. sp. ).

Wheat stripe rust, caused by f. sp. (), is one of the most important and devastating diseases of wheat; therefore, it is necessary to rapidly and accurately quantify fungicide effectiveness to monitor sensitivity and manage the disease. In this study, a rapid method of quantifying the fungicide effectiveness with detached leaves was developed. The results showed that 0.5% water agar containing 75 μg/ml of 6-benzylaminopurine and filter paper worked the best for maintaining wheat leaves. The disease incidences of different concentrations of spore suspension were compared. When the spore concentrations were 5 and 10 mg/ml, the disease incidences had no significant differences at 12 and 15 days after inoculation ( < 0.05). Fungicide treatment tests revealed that there were no significant differences in the efficacies of triadimefon on rust suppression between detached leaves in the culture dishes and direct spray on seedlings. We also developed a Photoshop software method that can replace the current classification method and accurately measure the proportion of sporulation area on infected leaves. The sensitivity baseline of to triadimefon was estimated as 0.1453 ± 0.0081 μg/ml, and all the values of EC were tested for normal distribution using the Shapiro-Wilk test ( = 0.204). The baseline can be used to test the sensitivity of different isolates to triadimefon.