Evaluación de persistencia en mezclas forrajeras con componentes perennes estival e invernal en el norte del país

The incorporation and domestication of forage species of Mediterranean and continentals’ origins have been strengthened in the Uruguayan pastoral systems, nevertheless in the North of the country the low resistance of these zones limit the potential productivity. One of the native species that has features to increase its persistence of traditional forage mixtures, is Paspalum notatum. In this paper it is expected to assess if the incorporation of this species mixed with forage components such as Festuca arundinacea, Dactylis glomerata, Trifolium repens and Lotus corniculatus, generates any positive effect in the increase of longevity of these browses in the zone mentioned. In order to accomplish this goal, the contribution of each component in each mixture and the survivorship of tillers of wintry gramineaes in the corresponding mixture were measured. Simultaneously, it was possible to obtain information about the productive behavior of the native summer grass in pure sowing; these figures are scarce in Uruguay. The data was collected since 12 th December 2022 until 5 th May 2023 in order to cover the summer season; which is considered critical for wintry species; and the beginning of autumn to control the summer grass and how it enters the season which is favourable for its growth and development. The browse plot that were assessed are four: Plot 1- compound only by Paspalum notatum, Plot 2, that included Festuca arundinácea, Trifolium repens and Paspalum notatum; plot 3A compound by Festuca arundinácea, Lotus corniculatus and Paspalum notatum; and plot 3B replaces wintry gramineae of the plot 3A with Dactylis glomerata and maintains the other components. Regarding the results obtained, according to the information available, it was inferred that the summer performance of Dactylis in a mixture would be better than in a mixture with Festuca, in addition to a lower level of weed infestation in the first species. In Paspalum, a better productive performance was expected in a mixture with Festuca, and, in pure sowing, it would be expected that the pasture would reach an established population and the entire area covered. In turn, these conjectures could not be verified almost in their majority, where the only affirmation that could be verified was the stable population of paspalum in pure sowing at its third year of age.