Parâmetros agronômicos e bromatológicos de variedades de milho grão e silagem em sistema orgânico

Abstract

Maize is one of the most cultivated cereal in the world for its wide range of use in food, feed and industrial use. The production of grain and maize silage in organic system is essencial for the production of organic meat, milk and eggs, because this cereal makes up most of the rations and roughages used in a animal feed The objective was to evaluate the agronomic performance and bromatological parameters of silage of five commercial varieties (AL Avaré, AL Bandeirante, Cativerde 02, AL Piratininga and UFVM 200 - Soberano) and two maize landraces (Santa Rita 1 and Santa Rita 2), in two locations with climatic conditions and different altitudes (Araras / SP, 665 m altitude and Muzambinho / MG, 1100 m altitude) in organic production system. The experiment was carried out in a randomized block design in a 2x7 factorial with four replications. For evaluating the agronomic performance, was measured stalk diameter, plants height, insertion height of the upper ear, leaf number above the upper ear, Falker index of total chlorophyll, leaf nitrogen content, number of rows per ear, number of grain by row and grains per ear, lodging, final stand, 1000 grain weight and productivity. For the evaluation of bromatological parameters of silages was evaluated the productivity of green (GM) and dry matter (DM) and percentage of total dry matter (TDM), acid detergent fiber (ADF), neutral detergent fiber (NDF), crude protein (CP), mineral matter (MM), ether extract (EE), total carbohydrates (CHOT), and non-fiber carbohydrates (NFC) in silage. By results obtained, it was concluded that the agronomic performance of corn grain and the production of green and dry matter silages were influenced by environmental conditions, especially temperature and solar radiation, with better results in Muzambinho. But the environmental conditions not affected the bromatological parameters of silages, which were suitable for all varieties, in both locations. Under the experimental conditions, the landraces showed agronomic performance and bromatological parameters of silage similar to that of commercial varieties in two locations evaluated, indicating that they can be used in commercial crops under organic management.