Endo- and Ectomycorrhizal Associations in Five Populus Species

Abstract

Vozzo, J. A. (Forest Tree Seed Lab., USDA Forest Serv. Starkville, Miss. 39759) and E. HACSKAYLO (Northeast. Forest Exp. Sta., USDA Forest Serv., Beltsville, Md. 20705). Endoand ectomycorrhizal associations in five Populus species. Bull. Torrey Bot. Club 101: 182-186. 1974.-After inoculation with mycorrhizal fungi in soil, Populus fremontii, P. grandidentata, and P. tremuloides formed ectomycorrhizae; P. heterophylla formed no mycorrhizae; P. deltoides and P. deltoides var. occidentalis formed both ectoand endomycorrhizae. Spores isolated from endomycorrhizal P. deltoides appear to be Endogone species. Respiration rates of P. deltoides were 2.8 pl 02/mg/hr for nonmycorrhizal roots and 3.0 gl for endomycorrhizae. Histochemical differences in the two kinds of roots suggest that protein synthesis is more active with mycorrhizae than with nonmycorrhizal roots.