Chemical Suppression Of The Growth Of Panicum Maximum Cv. Aruana Intercropped With Soybean Crop

At the soybean-forage intercrop, distinct forage species are being studied as possible to be intercropped with soybean, as well as differences between the time of sowing of the crop and the forage (concomitant of delayed planting) to enable competitive advantage for soybean plants in lieu of the forage. This study aimed to evaluate herbicides and doses suitable for application at the intercropping of soybean with Panicum maximum cv. Aruana, when the growth of the forage is excessive reaching levels capable of causing damage to the crop, resulting in lower yields. The trial was installed in strip-plot design with subsamplings, being the trial essentially composed of the delayed planting of Aruana grass in ten days after the crop at the intercrop soybean-forage. The effect of increasing doses of the herbicides glyphosate, fluazifop and fenoxaprop were evaluated when applied over intercropping of soybeans with Panicum maximum cv. Aruana, 55 days after emergence (DAE) of both species (the emergence occurred at the same time). Sixty nine DAE the fresh mass, dry mass, total chlorophyll, control level of aruana grass, tillers per plant and percentage of dead tillers of the forage were evaluated, as well as plant height and water content of the forage and crop plants, and crop yield. If the priority is the crop yield the herbicide glyphosate is indicated at expense of damage to forage establishment. On the other hand, if the intercropping aims to establish pasture after crop harvesting, the herbicides fluazifop and fenoxaprop represent a safer measure, allowing plants of the forage to establish properly at expense of higher interference over the crop.