Impacts of early- and late-seral mycorrhizae during restoration in seasonal tropical forest, Mexico

Disturbance of vegetation and soil may change the species composition of arbuscular mycorrhizal fungi (AMF), which may in turn affect plant species responses to AMF. Seasonal tropical forest in Mexico is undergoing rapid conversion to early-successional forest because of increased wildfire and may require restoration. The responses of six early- and late-successional tree species were tested using early- and late-successional AMF inoculum. The plants were germinated in the shadehouse and received three inoculum treatments: (1) soil from a two-year-old burned site, (2) soil from a mature forest site, or (3) uninoculated controls. They were transplanted as seedlings to a site prepared by burning, and their growth was measured from September 1997 to November 2000. All six species had the greatest growth response to early-seral inoculum, but the response to late-seral inoculum varied. Two tree species, Ceiba pentandra and Guazuma ulmifolia, were smallest with late-seral inoculum, even smaller than the uninocu...