In vitro fungicide-insensitive profiles of Sclerotinia homoeocarpa populations from Pennsylvania and the surrounding region. - Plant Disease, 103(2), p.214-222, 2019 .

Repeated fungicide applications are typically required to provide adequate control of dollar spot on golf courses and may shift Sclerotinia homoeocarpa populations from sensitive to insensitive or resistant to an active ingredient. The objective of this study was to characterize the geographic distribution of fungicide-insensitive, fungicide-resistant, and multiple fungicide insensitive (MFI)S. homoeocarpa populations on golf courses in Pennsylvania and the surrounding region. S. homoeocarpa isolates (n = 681)were collected from 45 different golf courses or research facilities. Each isolate was evaluated in vitro against propiconazole, iprodione, boscalid, and thiophanate-methyl using discriminatory concentrations of 0.1, 1.0, 1,000, and 1,000 µg of active ingredient per milliliter of PDA, respectively. Relative mycelial growth (RMG)values were used to determine sensitivity or insensitivity based on comparison with a baseline population. Of the 681 isolates evaluated, 81, 80, and 85 percent exhibited reduced sensitivity to boscalid, iprodione, and propiconazole, respectively. A total of 41


ARABIDOPSIS PROTEIN
BACTERIAL DNA
HISTONE
T DNA
T-DNA