Trichoderma atroviride como condicionador biológico em solos de diferentes texturas sob soja e milho

Abstract

Sustainable agriculture aims to reduce the harmful effects and prevent the degradation of soils caused by improper management. One method exercised in the field of research, for example, corresponds to soil conditioners to increase the potentials of physical, chemical and biological form. In this sense, the study proposed to evaluate the potential of the fungus Trichoderma atroviride ATROV14 as a soil conditioner. The hypothesis of the work indicates that the fungus T. atroviride ATROV14 optimizes the fertility and increases the enzymatic activity and the carbon of the microbial biomass, as well as the arbuscular mycorrhizal colonization. Therefore, the research was conducted in a greenhouse, using an entirely randomized design and in the format of four distinct trials - clay soil with soybean cultivar; clay soil with corn cultivar; sandy soil with soybean cultivar, and sandy soil with corn cultivar - in this case, each trial was arranged with two treatments (with and without inoculation of T. atroviride ATROV14) and eight repetitions each. The soil received inoculations with distilled water for the controls (no inoculation) and with T. atrioviride ATROV14 for the treatments with fungus. After plant growth to the flowering stage, soil was collected for fertility, microbial biomass carbon, respirometry, β-glucoside activity, phosphatase, arisulfatase, and fluorescein diacetate hydrolysis, while roots were collected to evaluate arbuscular mycorrhizal colonization. As for the results, the clayey soil with T. atroviride application and corn cultivation showed an increase in organic matter, CTC and C-org compared to the control without microbial application; in the sandy soil and corn cultivation trial, root mass and soil pH increased; and, in the sandy soil and soybean cultivation trial, soil P and Ca indexes increased when T. atroviride was applied. On the other hand, the use of T. atroviride resulted in the decrease of some variables, such as: enzymatic activity of β-glucosidase, pH, Sb, CEC and Mg in the test on clay soil and soybean cultivated soil; the enzymatic activity of FDA in the test on clay soil and corn cultivated soil; pH in the test on sandy soil and soybean cultivated soil; and Zn in the test on sandy soil and corn cultivated soil. Thus, T. atroviride ATROV14 gives different results depending on the crop and soil texture.