Production and quality of cover crops in soybean monoculture
Cover crops (CC) are an alternative to improve soil organic matter, capture labile nutrients and minimizing its leaching losses during long-term fallows, typical of agricultural systems with high frequency soybean (Glycine max L. Merr.). The objective was to evaluate the production and nutrient content of different CC in simplified system (soybean monoculture) under no-tillage. CC used were: (T) bread wheat (Triticum aestivum L.), (A) oat (Avena sativa L.), (V) vetch (Vicia sativa L.) and (A+V) oat + vetch. Upon drying the CC was determined: production of total aerial dry matter (MS), biochemical composition (cellulose, hemicellulose and lignin), macro- and micronutrients. Dry matter production in T and A ranged between 7.2 and 11.1 Mg ha-1, differing significantly from V with values between 4.1 and 4.6 Mg ha-1. Carbon concentration did not differ between CC (43-45% C). The amount of N accumulated in aboveground biomass ranged between 102 and 212 kg N ha-1, showing differences only between years. The concentration of structural polymers clearly differ between CC species, where T and A showed higher concentrations of cellulose and hemicellulose regarding V. Conversely, V showed higher concentrations of nonstructural carbohydrates and lignin than grasses. Winter grasses as CC were more efficient in producing MS and therefore more effectives to contribute to increased soil organic matter, promoting the recycling of macro- and micronutrients, preventing the leaching of those most labile.
Wheat-vetch, Biochemical composition
Duval, Matías E.; Galantini, Juan A.; Capurro, Julia E.; Beltrán, Marcelo J. 2017. Producción y calidad de diferentes cultivos de cobertura en monocultivo de soja. Ciencias Agronómicas (FCA-UNR) XXIX 7-13.