-Among the weeds that cause interference with the growth and development of barley the turnip stands out, especially by the high competitive ability for the resources available in the environment. The research objective with the study was to evaluate the competitive ability of barley cultivars to live with a turnip biotype. Experiments were installed in a greenhouse, in the experimental outlining of randomized blocks designed with four repetitions. The treatments were arranged in replacement series, consisting of proportions of barley plants and turnip: 100: 0, 75:25, 50:50, 25:75 and 0: 100% which was equivalent to 20: 0, 15: 5, 10:10, 5:15 and 0:20 plants per pot. The barley was represented by BRS Cauê, BRS Elis and MN 610 and the competitor by turnip. The competitive analysis was made through diagrams applied in replacement experiments, among with use of relative competitiveness indices. The leaf area (AF) and the dry mass of the aerial part (MS) were evaluated at 50 days after the emergence of the species. The results show that there was competition between barley varieties with the turnip with mutual damage to the species involved in the community. Turnip negatively modified the AF and the MS of BRS Cauê, MN 610 and BRS Elis demonstrating higher competitive ability for the means of the resources. The interspecific competition causes greater damage to the AF and the MS species than the intraspecific competition. Thus, the turnip control is recommended the turnip control even when present at low densities of plants infesting the barley.
Keywords:Hordeum vulgare, Raphanus sativus, competitive interaction. : 100:0, 75:25, 50:50, 25:75 e 0:100%, o que equivaleu a 20:0, 15:5, 10:10, 5:15
RESUMO -Entre as plantas daninhas que ocasionam interferência no crescimento e no desenvolvimento da cevada, destaca-se o nabo, em especial por apresentar elevada habilidade competitiva pelos recursos disponíveis no meio. Diante disso, objetivou-se com este trabalho avaliar a habilidade competitiva de cultivares de cevada ao conviverem com um biótipo de nabo. Foram instalados experimentos em casa de vegetação, no delineamento experimental de blocos casualizados com quatro repetições. Os tratamentos foram arranjados em série de substituição, constituídos por proporções de plantas de cevada e do nabo