EVALUATION OF INITIAL GROWTH OF CORN SEEDED INTO OATS AND HAIRY VETCH COVER CROPS MANAGED WITH AND WITHOUT HERBICIDES

Abstract

With the purpose of evaluating initial growth of com seeded into oats or hairy vetch cover crops, managed with and without herbicide, a trial was conducted in greenhouse, in the Agronomy School of UFRGS, in Porto Alegre, RS, Brazil. Treatments consisted of several systems tested in com pre-seeding (application of the herbicides 2,4-D or glyphosatc over oat plants or over the soil without this crop; com seeded into oats or hairy vetch cover crops not treated with herbicides; and com seeded in soil without cover crops, as well as without herbicide application). There 'ware also tested threc com seeding dates (0, l I and 22 days after herbicide applications). There were not observed interactions between factors tested; nevertheless, significant differences occurred for com plants dry matter when the crop was seeded at various intervals after herbicide applications. Glyphosatc or 2,4-D applications did not affect com plants growth; however, precedent crops of oats or hairy vetch reduced development of these piam& The combination of herbicide application and of oats cover crop affected com plants growth in a similar manner as did oats alone.