Épocas de corte e cultivares na composição mineral de feno de soja [Glycine max (L.) Merrill]

Abstract

The aim of the present investigation was to verify the influence of cutting periods on mineral composition of soybean hay. The experiment was conducted in Lavras, MG, Brazil, in the agricultural year 2001/02, on a typical Dystrophic Latosol. An experimental design in casualized blocks in factorial scheme 2 x 5 with three repetitions was employed, with two soybean cultivars MG/BR 46 (Conquista) and M-Soy 8400, and five cutting periods (stages R2, R3, R4, R5 and R6). Cutting periods have strongly influenced all the evaluated minerals, and significant interaction between cutting times and cultivars have been detected in P and K accumulation. On the whole, as cutting period was delayed, all minerals showed higher accumulation. Cultivar M-Soy 8400 showed higher K and Zn accumulation than MG/BR 46 (Conquista), standing out as the best option for hay production. According to the experimental results, development stage R4 presented the best cutting period for hay production, providing higher mineral accumulation and earlier clearance of harvest area.