Agronomic performance of sunflower intercropped with Urochloa ruziziensis
Sunflower cultivation is a viable alternative for the second crop in Campo Novo do Parecis, state of Mato Grosso; however, its low contribution to the land cover after harvest is an obstacle for the practice of the no - tillage system, which favors the maintenance of straw on the soil. The objective of this study was to evaluate the influence of the intercropping on the agronomic performance and yield of sunflower under different populations of Urochloa ruziziensis in the region of Parecis. The experiment was carried out in the experimental field in the Instituto Federal do Mato Grosso, campus Campo Novo do Parecis, state of Mato Grosso in the second crop of the 2016/17 agricultural year. The experimental design was a randomized complete block design with six treatments (0, 200, 400, 600, 800 and 1000 points of cultural value ha-1 of U. ruziziensis) and four replications. Sowing was performed on March 10th, 2017 using variety Helio 250. No significant effect was found among treatments neither did the mathematical regressions present statistical significance. The agronomic characteristics of the sunflower are not influenced by Urochloa ruziziensis sowing rates when sowed simultaneously due to the slow initial growth of the grass and the competitive efficiency of the sunflower after 30 days of the cycle.