RNGR.net is sponsored by the USDA Forest Service and Southern Regional Extension Forestry and is a colloborative effort between these two agencies.

U.S. Department of Agriculture USDA Forest Service Southern Regional Extension Forestry Southern Regional Extension Forestry

Skip to content. | Skip to navigation

Home → Publications → American Chestnut Proceedings → 1978 → Virulence of Endothia Parasitica Isolated from Surviving American Chestnut Trees

Virulence of Endothia Parasitica Isolated from Surviving American Chestnut Trees

Large surviving American chestnut trees may possess blight resistance if they are not infected with American hypovirulent strains of Endothia parasitica. To investigate this, isolates of E. parasitica were obtained in 1975, 1976 and 1977 from cankered tissues of large, surviving and small American chestnut trees (Castanea dentata), and from cankered Chinese chestnut trees (C. mollissima) growing in the Appalachian region. These tissue isolates and single-conidium progeny of tissue isolates were examined for pigment production, linear growth rate in vitro, tannin utilization and pathogenicity on disease-free American chestnut stump sprouts. A large variation in pathogenicity among isolates was observed. Most isolates from surviving American chestnut trees were moderately or highly pathogenic, when comparisons were made to two isolates from blight-killed American chestnut trees and a European-derived hypovirulent isolate, Ep43. Some isolates from a large American chestnut tree in Virginia were hypo-virulent ( weakly pathogenic).


Download this file:

PDF document Download this file — PDF document, 449Kb

Details

Author(s): Gary J. Griffin

Publication: American Chestnut Proceedings - 1978