Cultivos extremes ou misturas de forrageiras perenes de inverno para o sudoeste do Paraná

Abstract

The objective of this study was to evaluate the productive and qualitative performance of perennial winter pastures formed by forage species from the Poaceae, Fabaceae, and Asteraceae families, grown as monocultures and in mixtures, under the edaphoclimatic conditions of Southwestern Paraná, Brazil. The experiment was conducted in a randomized complete block design with eight treatments and four replications, evaluated over two consecutive agricultural years (2023 and 2024). The treatments consisted of Festuca cv. Aurora; Festuca cv. Fortuna; Festuca cv. Epagri 312; Festuca cv. Rizar; perennial oat cv. Santa Vitória; and Dactylis glomerata cv. INIA Aurus. The mixtures were Festuca + white clover cv. Estanzuela Zapicán + birdsfoot trefoil cv. São Gabriel, and Dactylis + white clover + chicory cv. Puna II. Productive and bromatological variables were evaluated, including dry matter yield, number of cuts, pasture utilization period, canopy height, light interception, tiller population density, and forage chemical composition, allowing an integrated characterization of pasture performance throughout the experimental period. Productive assessments were carried out during the entire forage utilization cycle, while bromatological composition was determined from representative treatment samples. The data were subjected to analysis of variance considering the effects of treatments, agricultural years, and the treatment × year interaction, adopting a 5% significance level. The results showed a significant effect of forage strategies for most analyzed variables, indicating that pasture botanical composition directly influences the productive and structural performance of perennial winter forage systems. Overall, mixtures showed superior performance compared to monocultures, especially for variables related to forage production and utilization. The mixtures composed of Dactylis glomerata + white clover + chicory and Festuca + white clover + birdsfoot trefoil stood out, presenting the highest dry matter yields, greater number of cuts, and longer pasture utilization periods, demonstrating higher productive stability and better temporal distribution of production throughout the experimental period. The agricultural year effect was significant for productive variables, with higher averages observed in 2024, highlighting the influence of environmental conditions on forage growth and biomass accumulation. Regarding bromatological composition, mixtures showed higher crude protein contents and lower fiber concentrations compared to grass monocultures, reflecting greater nutritional value of the produced forage. In general, the results indicate that botanical diversification through the use of perennial winter forage mixtures is an efficient strategy to simultaneously increase productivity, nutritional quality, and productive stability of pastures, contributing to the sustainability of livestock systems in Southwestern Paraná.