Seedlings of cashew trees of the brazilian cerrado inoculated with arbuscular mycorrhizal fungi and phosphate-solubilizing microorganisms

Abstract

Soil microbiota carries out important functions in ecosystems, since it influences growth, mineral nutrition and plant health. Phosphorus (P) is the most limiting nutrient in tropical soils and P-solubilizing microorganisms (PSMs) and the arbuscular mycorrhizal fungi (AMF) are the most important groups of the soil microbial community. The aim of this study was to evaluate the effect of inoculating PSMs and AMF on the development of cashew trees (Anacardium othonianum Rizzini) from the Brazilian Cerrado growing on different substrates. An experiment was carried out in a greenhouse and the experimental design was completely randomized with a factorial 4 × 2 arrangement of treatments: PSMs, AMF, PSMs + AMF and the control. In addition, two substrates were used: a pure one with a sandy loam texture and a mixture of clay loam and clayish textures. Twelve replicates were performed. Data were subjected to an analysis of variance, and means were compared with the Tukey test (p£0.05). The co-inoculation with PSMs and AMF resulted in greater height and shoot dry matter of seedlings compared to isolated inoculations with these organisms. Seedlings increased height and shoot fresh and dry matter when grown in a mixture of substrates (soil with clay loam and clay textures). The use of a mixture of substrates also resulted in a greater symbiotic efficiency of Glomus etunicatum.