Ascomycetous isolates promote soil biological and nutritional attributes in corn and soybeans in sandy and clayey soils

Abstract

Biological inputs are environmentally friendly agriculture practices for conserving natural resources in the face of the world's increasing demand for food, fiber and biofuels. The effects of beneficial non-mycorrhizal fungi on soil and plants are multifactorial and mostly unknown. In this regard, we aimed to assess the effects of five ascomycetous isolates, namely Beauveria bassiana, Metarhizium anisopliae, Pochonia chlamydosporia, Purpureocillium lilacinum and Trichoderma asperellum, on the biology and fertility of sandy and clayey soils from the Cerrado biome under corn and soybeans grown in a greenhouse. The fungal treatments produced some differences in soil microbial biomass, enzyme activity and fertility and consistently promoted arbuscular mycorrhiza (AM) colonization in both soils under corn and soybeans. Fungal applications significantly increased colonization efficacy of arbuscular mycorrhiza fungi (AMF) by 28%–72% in corn and from 57% to 105% in soybeans, relative to a control. A combination of principal component analysis and correlation analysis showed that applications of any of the five ascomycetous fungi increased AM colonization, and shoot concentrations of P, K, S and Cu in the corn assays, and shoot concentrations of K and phosphatase and fluorescein diacetate hydrolysis activity in the soil of the soybean assays. Thus, the application of fungal isolates, with the stimulation of root colonization, nutrient absorption and soil biological activity, may have effects on soil function and quality in the medium and long term. These findings can contribute to the development and adoption of more sustainable agricultural practices.