Consociation of Sunflower and Fodder Oilseeds - An Alternative for Mixed Production Systems

The process of agricultural development which takes place in Argentina has led to the loss of sustainability. Mixed systems could be an alternative for improving productivity and, at the same time, taking into account the environmental cost. The sowing of sunflower (Helianthus annus L.) consociated with other species can generate greater biomass and, in some cases, greater yield. Such practice is about the differential harnessing of resources. The aim of this work was to evaluate the production of sunflower consociation with Trifoliumrepens L., Lotus corniculatus, and Vicia sativa, and to determine the conditions of the remaining stubble. Treatments consisted in the use of monoculture sunflower with and without herbicides; intercrop sunflower with red clover, lotus and vicia. The yield of sunflower grain and the total air biomass of the stubble and of its components were evaluated at the time of harvesting, and, two and three months after harvesting. The highest value of available stubble at the time of harvesting was obtained in monoculture sunflower without herbicide. Two months after, there were no variations in the stubble biomass of the treatments. Three months later, there were significant differences registered between the treatments; the intercrops with red clover and lotus reached the highest volume of stubble. Under the conditions of this test, the highest productivity of sunflower was registered when sowed in monoculture and herbicide application was employed. No differences were registered between the intercrops, or between them and the monoculture with herbicide. Therefore, these systems could be considered as a production alternative to lessen the use of synthetic inputs, such as herbicides.