Canonical correlations of maize yield components with biological and chemical soil indicators in a subtropical climate

Understanding the interaction between chemical and biological soil variables and their impact on the agronomic performance of agricultural crops is critical for enhancing management practices and promoting sustainability in agriculture. Thus, this study aimed to identify canonical correlations between chemical and biological soil variables and the yield components of maize under a subtropical climate in Brazil. Six experiments were conducted, with planting carried out in two different seasons across three locations. Four experiments occurred in rainfed areas, while two utilized pivot irrigation during the 2020/2021 growing season. Three hybrids were sown with three replications in each experiment. All 54 experimental units were evaluated for chemical and biological soil variables, as well as maize yield components. A canonical correlation analysis was conducted between the groups of variables, along with a test for comparing means for the yield components. The planting in two different seasons was exclusively employed to increase the variability of the interaction among the evaluated variables and was not considered in the analyses and interpretations. The results underscore the profound influence of soil and climatic conditions on the interaction between variables, as observed through the canonical correlation. In the irrigated location, a significant correlation between chemical and biological soil variables was observed, accompanied by the highest means in yield components. This emphasizes the need for balanced fertilization to stimulate soil biological activity and enhance grain production. Conversely, in non-irrigated locations, a significant correlation between biological soil variables and yield components was found. Strategies aimed at mitigating the effects of water deficit, such as the addition of plant materials and crop rotation, emerge as viable alternatives. These practices promote the activity of soil microbiota, expanding benefits such as nutrient cycling, with consequential impacts on grain productivity.