Produtividade de gramíneas forrageiras hibernais em datas de semeadura

Abstract

White oats, Italian ryegrass and double-purpose wheat are species belonging to the Poaceae family, which are among the most commonly used annual cold season forage species in Rio Grande do Sul. Thus, the objective of the study was to evaluate the productivity, growth rate and interviews in first and last cut in different sowing times in the Western Border of RS. The experiment was conducted in the experimental area of the Federal University of Pampa - Campus Itaqui, RS between April and September 2018. The experimental design was a randomized complete block, with four replications, composed of 5 m² plots. The treatments were constituted by the species white oat (IPR Emerald), annual ryegrass (Barjumbo), doublepurpose (BRS Tarumã) and the dates of sowing April 13, May 22 and June 20. Herbage production (kg DM ha-¹), number of days until the first cut, interviews in first and last cut and dry matter accumulation rate (kg DM ha-¹ day-¹) were evaluated in successive cuts. Data were submitted to analysis of variance and comparison of means by Tukey test at 5% of probability. There was a significant difference (P <0.05) for sowing dates for the three species regarding total DM yield and number of cuts, with higher productivity and greater number of cuts at the sowing of April and for wheat at the sowing of May and June. There was a significant difference (P <0.05) for the number of days until the first cut and interval between cuts for the species white oats and ryegrass, being the sowing of May presented the highest number of days. White oats and wheat obtained a larger cycle when sown in April and ryegrass in May. For the accumulation rate, white oats and ryegrass obtained a significant difference (P <0.05) between the cuts, with higher sowing rates in May and June. In conclusion, white oats and wheat obtained higher yields when sown in April, ryegrass obtained higher yields when sown in May and June.