Silage produced with the entire corn plant (Zea mays L.) has been an increasingly widespread alternative as bulky food for ruminants. One of the main care in crop management with a view to silage production is related to fertilization. In tropical soils (such as those in the south of the state of Pará) phosphorus is the most limiting nutrient for agricultural production. Because of the above, the present work aims to know the agronomic performance of forage corn cultivars in high and low phosphorus in the South of the state of Pará. For this, two competition trials of maize cultivars under contracting conditions of phosphorus (P) were carried out: high P (100 kg ha-1 from P2O5) and low P (50 kg ha-1 from P2O5), using as a source the simple superphosphate (18% from P2O5). The experimental design was randomized blocks with fourteen treatments and three replications. The treatments were composed of fourteen cultivars, eleven of these were the hybrids: AG1051, AG8088, BM3061, BR2022, BR205, BR206, BRS3046, CR-120, M274, ORION, and PR27D28, and the other three were open pollination populations (PPA): AL BANDEIRANTE, ANHEMBI, and CATIVERDE. The variables evaluated were: height of insertion of the ear (AE) and plant height (AP), total weight per plant (PPT), the weight of the cob with straw (PESP), and weight of the ear without straw (PESP). The medium was compared by the test of groups of Scott and Knott, the 5% of significance, using the program SISVAR. Considering the overall performance of the cultivars, in all traits evaluated in the two trials, the sum of their results points to the cultivar BRS3046 as the most promising for silage production. The high test P, as expected, has been used about the low P.

Campus. The design used was randomized blocks, with ten treatments and three replications, where the treatments are represented by ten maize cultivars. The variables were measured when the plant reached R6 stage. For the study of genetic divergence, the following variables were analyzed: The number of grains per row (NGPF), number of rows per spike (NFE), plant height (AP), the height of the spike (AE), moisture (UMID), grain yield (kg). The Tocher method was used to verify similar groups; for the verification of genetic distance, there was the foundation through the generalized distance of Mahalanobis (D²) and Singh's criterion for quantifying the contribution of the variables evaluated. The characteristics of grain yield and number of grains per row were the ones that most contributed to the genetic divergence for treatments with Azospirillum and without Azospirillum. The crosses between cultivars aiming at promising combinations to obtain strains are BM3051 X CATIVERDE with Azospirillum and BM3051 X CATIVERDE without Azospirillum.

The lipid content in soybean grain can be influenced by environmental characteristics, pod positioning, and plant population. However, the objective is to evaluate the percentage of soybean lipids in different plant positions in populations of two crops, in the southern region of the state of Pará. In this sense, two tests were carried out, one in the agricultural year 2018/19 and the other in 2020/21, in Conceição of the Araguaia-PA. The experimental design used in each assay was randomized blocks with three replications. The treatments were arranged in plots sub-sub-sub-Subdivided, being allocated in the plots six cultivars, in the subplots three sowing densities (10; 14; 18 seeds m-1) and the sub-sub-two plots sites in the plant (on top and in the bottom third). The characteristic studied was the percentage of lipids. Individual variance analysis was performed and, later, joint analysis of the assays was performed. The highest averages of lipid contents were obtained in the lower third of the plant, with emphasis on the cultivars Ultra 75i77 IPRO, in the density of 18 seeds m-1 (24.3% crop 1 and 24.1% in the crop 2). The densities influenced the results, showing significant differences between them and being the best density of (18 seeds m-1). When the grains were collected in the lower third of the plant, they showed the highest lipid contents. Crop 1 was affected by the high temperature followed by a water deficit in the grain filling phase, showing that in November in southern Pará you can get summer in the R5.1.