Estratégias na ensilagem de milho : modalidades de cultivo consorciado com capins e acondicionamento em função da maturação do grão e tempo de armazenamento

Abstract

Forage conservation through silage has undergone many advances in recent years. the cultivation of forage crops through intercropping and the implementation of packaging techniques are some of the recent strategies that have been gaining prominence in the conservation practices. In this sense, the objective was to characterize sowing modalities in intercropped cultivation and silage packaging methods depending on maturation stages and storage time. To achieve this, two experiments were carried out. One of them, composed of grass cultivar factors (Marandu palisadegrass and Mombasa guinea grass) and sowing modalities (simultaneous sowing in the row and between the row, simultaneous sowing of a double row of grass between the corn row and delayed sowing between the row after corn emergence). The second experiment focused on studying the crop maturation factors at harvest at maturation (stages R3 – Kernel Milk Stage, R4 – Kernel Dough Stage, R5 – Kernel Dent Stage and R6 – Physiological Maturity Stage) and silage storage time (0, 2, 7, 14, 21, 30 and 60 days), both under different forms of conditioning during ensiling (conventional and vacuum). Agronomic and productive analyzes were carried out on the cultivation in both trials, as well as fermentative analyzes on the ensilage and bromatological composition of the silages produced. In general, silages with good characteristics and bromatological composition were obtained. In the first work, simultaneous or lagged semesters can be recommended as consortium cultivation strategies. The Mombaça cultivar presented higher (P<0.05) values of forage buffering capacity and lower (P<0.05) ammonia nitrogen content of silage in different sowing methods. In the second work, the harvesting and ensiling of corn at different stages of maturation was based on plants with structural changes in terms of the green leaf and ear throughout the cycle. The R5 stage stands out for maintaining dry matter (DM) content. Between stages R3 and R6, the DM content showed average variations of 19.78 and 43.36% and 18.49 and 42.16% in conventional and vacuum packaging, respectively. Under the same conditions, crude protein levels reduced from 8.30 to 6.70% and 8.38 to 6.77%. Longer storage times promote significant changes (P<0.05) in terms of reducing neutral detergent

fiber and increasing starch in conventional silage and in disposable bottles. The average pH of the silages was 4.28 and 3.88 in conventional packaging and in the vacuum cleaner, respectively. Aerobic stability is directly influenced by the stage of maturation, varying between 32.25 and 60 hours in conventional packaging and 28.50 and 60 hours in vacuum packaging. Thermal conditioning can be recommended for silage harvested later, under appropriate pH values (3.90) and dry matter recovery (97.29).