Evaluation of Chinese chestnut cultivars for resistance to Cryphonectria parasitica.

Seedlings of 13 Chinese chestnut cultivars were inoculated with and evaluated for resistance to Cryphonectria parasitica. Canker widths differed among the cultivars. Cankers increased for 1 week after inoculation but gradually constricted through callus formation; cankers on American chestnut controls expanded at a rate of 0.6 ± 0.3 mm per day until stems were girdled. Isolates of C. parasitica caused differential responses in Chinese and American chestnut.