Effects of spore inoculation of edible mycorrhizal fungi on the morphological development of Pinus hartwegii seedlings

Abstract

Pinus hartwegii forests have several fungal species with high economic and ecological value; however, the fungus-plant interactions involve in plant’s morphological development, are unknown. The purpose of this study was to evaluate the morphological attributes of P. hartwegii seedlings, inoculated with ectomycorrhizal fungi (EMCF) spore’s solution on greenhouse, and know its effect on this forest specie development. Seedlings were inoculated at four and eight months using three ECMF spore solution in separated treatments: Russula brevipes, Russula emetica and Lactarius deliciosus. After 18 months, seedlings were evaluated through dasometric variables such as height, stem, and crown diameter. Also, biomass was obtained in three structural components (stem, foliage, and root) through dry weight. Additionally, chlorophyll concentration (α and β), carotenes and mortality rate were measured (based on the formula of Trigueros-Bañuelos et al., 2009). Root architecture (number and length of roots) was measured with the EZ-Rhizo program. Dasometric variables showed differences (p=0.05) between fungal treatments, but plant biomass did not show differences between treatments. Correlation between direct variables (stem diameter, height, and crown diameter) and indirect variables (stem, foliage, and root) showed a strong relationship between stem diameter (r² = 0.97) and foliage (r² =0.96). Chlorophylls and carotenes showed no significant relationship between fungal treatments. The annual mortality rate was significantly high (80%) in the three treatments. Roots in L. deliciosus treatment showed a maximum length of 364.93 cm. ECMF are important in P. hartwegii’s development, the greatest efficiency was observed in R. emetica and L. deliciosus treatment.