Aspectos agronômicos e qualidade de silagens mistas oriundas dos consórcios de milho e crotalárias

Abstract

This study aimed to evaluate the agronomic characteristics and nutritional value of single maize (SM), maize + C. juncea (MCJ), maize + C. spectabilis (MCS), maize + C. ochroleuca (MCO) in two spatial arrangements (A1 = 45 cm between rows, with maize and legume on the same line; A2 = 45 cm between rows, with maize and legume in alternating line). The end products of the fermentation, microbial population and nutritional value of the silages derived from the intercrops were evaluated too. The experiment was divided into two tests: Test 1 - evaluation of productivity, morphological composition and nutritional value of intercropping. Test 2 - evaluation of fermentation products, microbial populations, aerobic stability and nutritional value of mixed silages from intercropping. The lowest total maize production was found for MCJ (8,280 kg/ha) due to the higher proportion of legume obtained in this intercropping (39.8%). Higher yields of dry matter (13,094 kg/ha) and stem ratios (275.6 g/kg) were found in the A2 test for SM. The lowest proportion of maize leaves was found in the A2 arrangement (167.4 g/kg). The highest proportion of legume leaf was found in the MCS intercropping (369.6 g/kg). The highest levels of crude protein (95.1 g/kg) and acid detergent fiber (340.6 g/kg) were described in the MCJ intercropping, however these results did not reflect directly in the dry matter digestibility (754.4 g/kg). The inclusion of legume up to the analyzed levels did not affect the production of acids. Higher NNH3 levels (159.0 g/kg) were found in MCJ silages. The highest crude protein levels were described in the MCS silages (97.5 g/kg). The values of neutral detergent fiber and acid detergent fiber were higher for all legume treatments, however, there was no interference in the in vitro dry matter digestibility. The mean stability break times ranged from 32 to 40 hours for temperature, and 40 to 48 hours for pH. It is concluded that the use of C. juncea sown in the maize line could maximize productivity per area, without reducing the fermentation quality of the silage.