The objective of this work is to study the agronomic performance and genetic divergence in corn in the Cerrado-Amazon ecotone. The trials were conducted in the 2017/18 harvest at a property in the state of Pará. The experimental design was a randomized block with nine treatments and three replications, where the treatments are represented by nine cultivars of corn. The characteristics to evaluate agronomic performance and genetic divergence were: ear height (cm), plant height (cm), ear length (cm), ear diameter (mm), number of rows, number of grains per row and grain yield (kg ha−1). The cultivars were separated into a multivariate model in five groups using the Tocher optimization method. The cultivar AG 1051 showed the best agronomic performance. The results of genetic divergence were according to the generalized distance of Mahalanobis (D2), with the commences AG 8088 x CATIVERDE and AG 1051 x AL BANDEIRANTE, the most promising for future crosses.

Corn is of great importance in the national economy, being one of the most produced and exported cereals in Brazil. With the growing concern of producing food for the population, the search for new corn genotypes is increasingly intensified in order to obtain efficient seeds with an adequate response to the particularities of each planting region. In this sense, the present work aims to identify genotypes of corn efficient and responsive to the use of nitrogen for grain production in the Cerrado biome. The studies were carried out in two maize trials at the

Todo o conteúdo deste livro está licenciado sob uma Licença de Atribuição Creative Commons. Atribuição 4.0 Internacional (CC BY 4.0).O conteúdo dos artigos e seus dados em sua forma, correção e confiabilidade são de responsabilidade exclusiva dos autores. Permitido o download da obra e o compartilhamento desde que sejam atribuídos créditos aos autores, mas sem a possibilidade de alterá-la de nenhuma forma ou utilizá-la para fins comerciais.

The management of nitrogen fertilization is of paramount importance for the increase of corn silage productivity, by directly participating in the processes of cell division and expansion.It is extremely important to identify the characteristics that are associated with the responsiveness of the use of nitrogen fertilization.Therefore, this study aims to identify the characteristics that most influence the total weight in maize silage production.Two trials were conducted, one with low nitrogen dosage (0 kg ha -1 of N in cover) and the other with a high dosage (120 kg ha -1 of N in cover), performed in the harvest 2017/18, in Sítio Vitória, in the municipalityof Santa Maria das Barreiras, State of Pará, located in the ecotone Cerrado-Amazon. The experimental design used was randomized blocks with eleven treatments and three replications.The treatments used were BRS 3046,

The present work was carried out to study, through track analysis, the characteristics that most influence grain yield in corn genotypes. The trials were conducted in 2017/18, in the municipality of Santa Maria of Barreiras – PA, a region located in the Cerrado-Amazon Ecótono. Two competition trials of maize cultivars were installed, one in low phosphorus conditions, with 50 kg ha-1from P2O5, and another under high phosphorus, with 100 kg ha-1from P2O5. The experimental design used in each assay was randomized blocks with three replicates and ten treatments (genotypes). The treatments consisted of cultivars found in the local market, which were AG8088PRO2, BRS3046, PR27D28, ANHEMBI, CATIVERDE, 2B655PW, BR206, AG1051, AL BANDEIRANTE, and ORION. The characteristics of plant height were evaluated (AP), height of the spike (AE), diameter of spike (DE), length of spike (CE), and number of grains in row (NGE), weight of the spike (PE) and productivity (PROD). The track analysis was done through the computer program Genes. The variable PE presented the greatest direct effect on yield in corn genotypes in the Cerrado-Amazon region, being the most indicated for indirect selection for grain yield.