Native Arbuscular Mycorrhizal Fungi Exhibit Biotechnological Potential in Improvement of Soil Biochemical Quality and in Increasing Yield in Sugarcane Cultivars

The optimization and sustainability of farming systems are essential. The use of biotechnologies, such as the increase in the density of arbuscular mycorrhizal fungi (AMF) propagules, can be an important technique to maximize the effects of fertilizers and benefit the plant and, consequently, increase the biomass and microbial activity in the soil. This study evaluated the effect of inoculation of native AMF on soil biochemical quality and the yield of different sugarcane (Saccharum species hybrids) cultivars. The experiment was conducted in the field following a randomized block experimental design in 6 × 2 factorial arrangements [sugarcane cultivars (CTC 1, CTC 7, CTC 9, CTC 16, SP89-1115, and RB925345) and inoculation of AMF], in two ratoon crops. The native AMF were inoculated through application of inoculum soil in the planting furrow at the time of sowing  the crop. At the end of each ratoon crop, the following traits were evaluated: microbial biomass carbon and nitrogen, soil respiration, enzyme activities (β-glucosidase, urease, phosphatase, and fluorescein diacetate hydrolysis), mycorrhizal colonization and sugarcane yield. The increase in biomass and in microbial activities in relation to inoculation with native AMF led to increases in sugarcane yield, but the more prominent were CTC1, CTC7, and CTC9. The increase in the density of the native AMF by means of inoculation with inoculum soil favored soil biochemical quality and increased the yield of the sugarcane cultivars, regardless of the known yield potential of each cultivar, with reduction in production costs.