Estratégias de manejo de cereais de inverno para produção de forragem verde e silagem

Abstract

This study consisted in agronomic and nutritional evaluation of winter cereals submitted to an integrated management system for mass forage and silage production. The following materials were evaluated: wheat (Triticum aestivum cv. BRS Gralha Azul), barley (Hordeum vulgare cv. BRS Brau), white oat (Avena sativa cv. URS Guará), black oat (Avena strigosa cv. Embrapa 139) and triticale (X Triticosecale cv. IPR 11) in three management strategies: no vegetative stage cuts (T1), a cut (T2), and two cuts (T3), and subsequent production of silage for each treatment. The black oat was the material with high fresh forage mass production (720 kg ha-1) differing only of barley (400 kg ha-1) vegetative stage with a cut, while in forage mass production for silage with the increased number of cuts the production was reduced in the materials, and triticale kept higher yield (P <0.05) to the remaining material (12,317; 11,336 and 5,915 kg ha-1) having high production stability to the management of successive cuts. In the nutritional assessment of the vegetative stage cuts, cereals were similar in the evaluated parameters. In the evaluation of silages, barley showed better results in nutritional value to the system with one and two cuts and higher dry matter recovery rates with white oat for the three cutting managements. For aerobic stability, silages were very similar and were considered to have good stability after opening the silos, with the exception of white and black oat without cuts management. In the assessment of winter cereal silages submitted to different storage times, barley showed higher values (P <0.05) of NDT (558.2; 544.7 e 531.6 g kg DM-1), regardless of time storage, and higher average ruminal disappearance (50.03%) but did not differ of triticale in this regard (48.16%). The storage for more than 60 days brought no benefits for the qualitative parameters of silages of winter cereals.