RENDIMENTO DE CULTURAS AGRÍCOLAS E DECOMPOSIÇÃO DE PALHADA EM SISTEMAS INTEGRADOS DE PRODUÇÃO

Abstract

For the success of no-tillage system it is essential that the soil has straw in quantity and quality, so the consortium is an option. The objective of this work was to evaluate cover plants and consortia of agricultural crops with forage and the subsequent decomposition of these straws in integrated production systems. The project was carried out for two years in the agricultural crops of 2018 and 2019 in Rio VerdeGO and Montividiu-GO municipalities. The evaluated treatments were: 1) Corn in monoculture; 2) Corn intercropped with Urochloa ruziziensis; 3) Sorghum intercropped with U. ruziziensis; 4) Sorghum in monoculture; 5) Corn intercropped with U. brizantha cv. Marandu; 6) Corn intercropped with U. brizantha cv. BRS Paiaguás, in the first study and 1) Corn in monoculture; 2) Corn intercropped with Urochloa ruziziensis; 3) U. ruziziensis in monoculture; 4) Sorghum intercropped with U. ruziziensis; 5) Sorghum in monoculture; 6) Corn intercropped with U. brizantha cv. Marandu; 7) U. brizantha cv. Marandu single; 8) Corn intercropped with U. brizantha cv. BRS Paiaguás; 9) U. brizantha cv. BRS Paiaguás single; 10) Sunflower intercropped with U. ruziziensis; 11) Crotalaria spectabilis; 12) Millet; 13) Mix (Milheto, C. spectabilis and U. ruziziensis), in the second study. The grain yield of grain crops, the dry mass yield of cover crops and the decomposition of different straws were quantified during the soybean cycle sown in the following harvest. When any effect was considered significant (p <0.05), the means were obtained by the method of least squares and compared by Tukey test, at 5% probability, using the statistical software R. After harvesting agricultural crops and desiccation of the cover plants, the soybean culture was sown and nylon bags with samples were installed in the area for the evaluation of vegetable residues decomposition. These samples were taken at 30, 60, 90 and 120 days, obtaining the decomposition curve for each one. The sorghum consortium with U. ruziziensis did not affect the grain yield of the crop when late planting was used showing to be an efficient type of consortium for both locations. The corn consortium with U. ruziziensis stood out in Rio Verde-GO and the corn consortium with U. brizantha cv. BRS Paiaguás in Montividiu-GO, being intercropping options for late planting. The late planting of the consortia associated with a smaller plant population of agricultural culture may have favored the forages in the competition, mainly in the corn. Thus, it is recommended to plant these consortia during the most favorable planting conditions, so that the agricultural culture can stand out in the competition and not have an influence on grain yield. Regarding biomass production, among the consortia, corn with U. brizantha cv. Marandu produced the largest amount of biomass. Among the straws that most remained in the final soybean cycle was corn intercropped with U. brizantha cv. Paiáguas. The coorn straw in monoculture showed the longest half-life.