TY - JOUR T1 - Root disease of Castanea species and some coniferous and broadleaf nursery stocks, caused by Phytophthora cinnamomi JF - Phytopathology Y1 - 1945 A1 - Crandall, B.S. A1 - G.F. Gravatt A1 - M.M. Ryan AB -

The fungus, Phytophthora cinnamomi Rands, is responsible for a destructive root rot of Chestnut and Chinkapin trees (Castanea spp.) in the United States. The author gives an outline of the work leading to the identification of the fungus, and reports on inoculation and field tests that have proved its pathogenicity on Chestnut and other hosts. The fungus causes a similar root disease in forest-tree nursery stock. Infection has been observed in the nursery on twenty broadleaf and coniferous species. Field and greenhouse inoculation tests have demonstrated the susceptibility to the disease of European Chestnut (Castanea sativa). The Asiatic species, C. crenata, C. mollissima, C. henryi, and C. seguinii, however, show a high degree of resistance. It seems probable that root rot of this type has been responsible for the recession of the American Chestnut in some areas of the United States. No satisfactory control measures have been evolved. Hybrid varieties resistant to both blight and root rot are being developed by crossing American Chestnut and Chinkapins with Asiatic species.

VL - 35 ER -