Dinâmica da produção e valor nutritivo de pastagens do gênero Cynodon consorciadas com amendoim forrageiro estolonífero

Abstract

A study was developed simultaneously in Southwestern of Paraná and the Depressão Central of Rio Grande do Sul, to evaluate the production, structural and botanical components, nutritive value and morphogenetic character (exclusively in Paraná) in pastures of Coastcross-1 and Tifton 85 mixed with forage peanut (0, 25, 50 and 75% of implanted area). The experimental design was factorial (three factors), distributed in a randomized block design with three replications, the factors were cultivars (2), the percentage of area located in the legume (4) and evaluation periods. Forage production was higher for cv. Tifton 85, particulary in the second crop year, however, showed no effect of the increase of forage peanut in deployment of pastures. The increasing area implanted with legumes decreased participation of fractions leaf blade, stem and dead material in pastures. In Paraná, the use of 75% of the area planted with forage peanut promoted approximate 30% of total massa forage legume, unlike Rio Grande do Sul, with the same percentage of inclusion did not exceed 15%. The increasing presence of the forage peanut mass in the system increased the nutritive value of the pasture. In Paraná, the cv. Coastcross-1 showed better nutritive value compared to Tifton 85, and, the inclusion of forage peanut positively changed the crude protein in the leaf blades of grasses studied, from the second year of establishment. The number of green leaves, growth and senescence rate were similar among cultivars, but, cv. Coastcross-1 showed a higher number of expanded leaves and leaf appearance rate and lower phyllochron and leaf lifespan. Lower average daily heat accumulation decreases the development of grasses studied, although more pronounced in cv. Tifton 85.