Efficiency of Desiccation, Decomposition and Release of Nutrients in the Biomass of Forage Plants of the Genus Brachiaria After Intercropping with Sorghum in Integrated Systems for Soybean Productivity

Abstract

ABSTRACT The implementation of more sustainable soil management strategies, such as the use of cover crop for no-till system with crop rotation, can help increase nutrient use efficiency and consequently decrease the use of mineral fertilizers for agriculture. In this context, the objective was to evaluate the efficiency of desiccation, decomposition and release of nutrients in the biomass of forage plants of the genus Brachiaria after intercropping with sorghum in integrated systems for soybean productivity. The experiment was conducted in the field in two agricultural seasons in randomized block design with four repetitions. The treatments consisted of biomass obtained after sorghum intercropping with forage plants of the Brachiaria genus (Brachiaria ruziziensis, Brachiaria brizantha cv. Marandu, Brachiaria brizantha cv. Xaraés, Brachiaria brizantha cv. BRS Piatã, Brachiaria brizantha cv. BRS Paiaguás, Brachiaria cv. BRS Ipyporã), sorghum biomass in monoculture, which after cutting for grain production, remained fallow for one year and an additional soybean treatment without soil cover biomass. The results showed that Cropping systems on sorghum and forage biomass resulted in a 25.64% increase in soybean yields compared to soybeans grown without soil cover. The use of tropical forage as a cover crop in integrated systems proved to be an efficient technique for biomass production, in order to minimize the effect of water deficit during soybean development, and nutrient cycling, which resulted in the replacement of mineral potassium fertilization for the no-till soybean system, by making better use of soil nutrients and contributing to greater sustainability.