Pinus greggii ENGELM.: RESPUESTA A LA INOCULACIÓN MICORRÍCICA CONTROLADA Y A LA FERTILIZACIÓN EN VIVERO

In Mexico, Pinus greggii Engelm. in nursery must reach morphological and physiological standards set by the Mexican Standard for the Certification of the Operation of Forest Nurseries (NMX-AA-170-SCFI-2016), where nutrition and the presence of mycorrhizae are emphasized. The objective this study was to evaluate the growth of Pinus greggii in the nursery stage, based on mycorrhizal inoculation with two commercial products and a controlled release fertilizer in two doses. The hypothesis was that at least a combination of type of inoculant and fertilization dose would favor the growth of the plants in a greater proportion. The experimental design consisted of complete randomized blocks with nine treatments. Data were analyzed with ANOVA and the means of treatments were compared with the Tukey test. At 11 months after sowing, morphological variables, quality indices, percentage of survival and mycorrhization were analyzed. In addition, the developed ectomycorrhizae were characterized. Survival ranged from 64 to 99%, with the highest percentages in treatments inoculated only with native or exotic fungi. Plants showed significant differences in morphological variables; the combined treatments, regardless of the dose or type of inoculant, showed better results. The percentage of mycorrhizal colonization ranged from 37 to 63%, and the treatments with better response were those inoculated with spores of exotic fungi and fertilized (both doses). The diversity of fungal spores contained in the commercial inoculants did not coincide with the fungal species that established symbiosis with P. greggii. Thus, the addition of controlled release fertilizer and inoculation with commercial products resulted in quality plant production.