Potencial produtivo de genótipos de milheto para o semiárido em diferentes idades de corte

Abstract

Assuming that millet has both quantitative and qualitative forage potential for its production in semiarid regions under rainfed conditions, this study aimed to evaluate the productive characters by forage yield variables of four millet genotypes (BRS 1501, IPA BULK 1, ADR 500 and ADRf 6010), and its best cutting age, followed by indication for use at four different ages (35, 42, 49 and 56 days), as a function of morphophysiological characteristics at different phenological stages of development, evaluating the agronomic characteristics and chemical composition. The variables studied were: Green mass production (MV), Dry mass (DM), Percentage of dry mass (PMS), Plant Height (AP), Stem Diameter (DC) and Number of Leaves (NF), and the Chemical composition with the variables, Mineral Matter (MM), Crude Protein (PB), Ethereal Extract (EE), Lignin (LIG), Cellulose (CEL), Fiber in Neutral Detergent (FDN) and Fiber in Acid Detergent (FDA), Hemicellulose (HEM), Total Carbohydrates (CHOT), Non-Fibrous Carbohydrates (CNF) and Total Digestible Nutrients (NDT). The means were submitted to analysis of variance and regression using the computer software R version 4.0.3. The ADR 500 and IPA Bulk-1 genotypes stood out in the VM productivity variables at all cutting ages, reaching productivity above 50 T ha-1, whereas for DM, the ADR 500 and IPA Bulk-1 genotypes were superior to the genotypes 35 days, not differing from ADRf 6010 at 42 days, and not differing from the others at 49 days, where they reached a productivity between 8 and 9 T, while the BRS 1501 genotype stood out in the variables PB, FDN, FDA, not showing a sharp decline until the 49 days. Although forage quality is in decline in relation to cutting age, the millet crop is very promising for cultivation in the Northeast region, since it meets, in quantitative and qualitative terms, most animal nutrition parameters. Based on the response achieved with the averages presented, it is concluded that the ADR 500 and IPA BULK genotypes reached the best production rates and can be used for grazing at 35 days, used as grass at 49 days, where they reach their best yield x ratio forage quality, and can be used for silage at 56 days, presenting its highest production index combined with the maturity stage of its panicles.