Weed species diversity indices in legume - cereal additive series intercropping

In order to investigate the effect of additive series intercropping of legume and cereal (the line of 2561 of broad leaf vetch and Abidar cultivar of barley) on species diversity ecological indices and weeds dominance, a field experiment was conducted in 4 × 5 factorial with three replications in the dry land conditions in the research farm of the Faculty of Agriculture, University of Lorestan in the cropping years of 2015-17. The intercropping treatments reduced numbers and total dry weight of weeds ratio in sole cropping. The best treatments in first and second year for weeds control were once-weeding and seed ratios 70:100 and 100:100 (vetch: barley) and double-weeding×70:100. The three factor interactions (year, weed and intercropping) represent the contribution of 40:100 and 70:100 with once-weeding in weed dry weight losses (17.98 and 17.16 in the first and second years, respectively). In the second year, this interaction also resulted to the lowest weed dry weights (20.82 and 20 g/m-2). The lowest species richness was belonged to once and double weeding and non-weeding treatments with 100:100 seed ratio, respectively. Also, mentioned treatments indicated the weeds were more dominance in the first year compared to the second year.