Cultural characteristics of Botrytis cinerea isolates on potato dextrose agar. (A) Four-day-old (top) and 20-day-old cultures (bottom) of isolates QT5-19, 08168, B05.10, and XN-1 (20 °C). Note difference in colony color, pink for QT5-19, whereas gray for the other three isolates. Note also difference in sclerotial color, orange sclerotia produced by isolate XN-1, whereas black sclerotia produced by isolates 08168 and B05.10; (B) A histogram showing average mycelial growth rates of the four isolates. Means ± S.D. (n = 4) labeled with the same letters are not significantly different at p > 0.05; (C) PCR-based identification of QT5-19 using the B. cinerea-specific primer set Bc-f/Bc-r and the universal primer set ITS1/ITS4. Isolates 08168, B05.10, and XN-1 of B. cinerea were used as reference.