Produtividade do sorgo granífero de segunda safra sob diferentes doses de nitrogênio e micronutrientes foliares no cerrado piauiense

Abstract

Sorghum (Sorghum bicolor (L.) Moench) is a crop of great importance for food security and agricultural economy, especially in tropical and semi-arid regions. In the Piauí Cerrado, the search for maximizing productivity and input efficiency is constant. This study aimed to evaluate the interaction between topdressing nitrogen (N) rates and foliar application of a cobalt (Co), molybdenum (Mo), and nickel (Ni) complex on the productivity and nitrogen use efficiency of second-crop grain sorghum. The experiment was conducted at Fazenda Ipê, in Baixa Grande do Ribeiro - PI, using the 1G233 hybrid. The experimental design was a randomized block design (RBD), in a 3x5 factorial scheme, with four replications. Treatments consisted of three N rates (0, 45, and 90 kg ha⁻¹) and five foliar rates of the SeedDry + Ni complex (0, 30, 60, 90, and 120 g ha⁻¹ of Mo). Growth variables, yield components, and grain yield were evaluated. The results indicated that the application of N and the micronutrient complex significantly influenced panicle weight, and productivity. The highest panicle weights and productivity were observed in treatments with 45 kg ha⁻¹ of N combined with the highest rates of the SeedDry + Ni complex, suggesting a synergistic interaction between these nutrients. The optimization of nitrogen nutrition, catalyzed by the presence of Mo, Co, and Ni, proved crucial for maximizing sorghum yield, highlighting the importance of foliar application of these micronutrients for nitrogen use efficiency and sustainable production in the Cerrado