Agronomic performance of eight corn genotypes in two sowing periods

Resumo

Climatic factors of a region determine the critical periods of corn crop development and affect the sowing planning in order to reduce the negative effects on yield. This study aimed to evaluate the agronomic performance of eight corn genotypes and two sowing dates in the edaphoclimatic conditions of Manaus, Amazonas. Four experiments were carried out in the agricultural years 2016/2017 and 2017/2018, conducted in two sowing periods under harvest season and off-season conditions each year. The sown of the harvest season and off-season were made in October and March, respectively. The experiments were conducted in a randomized block design, with eight genotypes (four varieties - BR 106, BR 5011 Sertanejo, BRS 4103, and BRS Caimbé; and four hybrids - AG 1051, BRS 1055, BRS 3040, and BRS 3046), and four replicates evaluated in two sowing periods for each year. The data were submitted to individual variance analysis for each sowing period, joint for each year, and to the means comparison test. Corn cultivation at the Manaus region could be carried out both during the harvest season, sowing at the beginning of the rainy period (October), and in the off-season, with sowing near the end of the rainy period (March). Hybrids have higher yield potential than open-pollinated varieties for both grain and green ear cultivation, regardless of sowing, harvest, or off-season.