Initial growth and phosphorus and nitrogen uptake of Enterolobium contortisiliquum inoculated with arbuscular mycorrhizal fungi

Abstract

Enterolobium contortisiliquum is a leguminous tree that associates by symbiosis with arbuscular mycorrhizal fungi (AMF) and can be used to recover degraded areas. Therefore, the aim of this work was to evaluate the effects of AMF inoculation, supply of phosphorus (P), and rate of nitrogen (N) and P absorption in E. contortisiliquum. The variables were analyzed into randomized blocks with factorial design 5 x 3, in which the factors were levels of P (0, 50, 100, 200, and 400 mg kg^-1), and inoculation with AMF (Gigaspora margarita and native population in soil), or non-inoculation (control treatment), with four repetitions in each treatment. The highest mycorrhizal colonization (35%) occurred in seedlings inoculated with G. margarita. Plants inoculated with G. margarita and under P supply of 0 and 50 mg kg^-1 exhibited increase in height of 19.5% and 7.4%, respectively, compared to the control treatment. P levels in aerial part of plants inoculated with G. margarita, under levels of 0, 50, 100 and 400 mg kg^-1of P presented high increment of 198%, 108%, 181% and 106%, respectively, compared to the control. The control treatment, without any P supply, seedlings inoculated with G. margarita exhibited high colonization efficiency (34.89%) and high mycorrhizal dependence (25.53%).