Growth and fungal persistence by Quercus rubra inoculated with ectomycorrhizal fungi and planted on a clear-cutting and strip mine

Abstract

Quercus rubra seedlings were grown in a greenhouse in media inoculated with and without vegetative hyphae of the ectomycorrhizal fungi Pisolithus tinctorius, Cenococcum geophilum, Scleroderma auranteum, and Rhizopogon nigrescens. Some seedlings were also inoculated with basidiospores of P. tinctorius and S. auranteum in the greenhouse. Rhizopogon nigrescens did not infect the seedlings during greenhouse production. Seedlings were planted and grown for two seasons on clear-cut and strip-mine sites. Some nonmycorrhizal seedlings were inoculated with basidiospores at planting. Seedling growth after one season on the clear-cut site was positive for all P. tinctorius, C. geophilum, and vegetative S. auranteum inoculations and significant differences in growth occurred among inoculation treatments. Root-core samples after one season showed that 80–100% of the seedlings on the clear-cut site had fungal persistence of assigned fungal species from all fungal inoculations except that no ectomycorrhizae were evident with seedlings field inoculated with basidiospores. Growth after two seasons on the clear-cut site was significantly different among treatments but not significantly different on the strip-mine site. Excavated root systems after two seasons showed that 0–100% of the seedlings on the clear-cut and strip-mine sites had fungal retention of assigned fungal species and ectomycorrhizae from basidiospore chip inoculations.