The field experiment was carried out on the lands of the village of Zhrebino in the region of Jambol, in the period 2006-2008. Eight variants were tested for this study – Stretch (15 g/ha), Derby Super (33 g/ha), Puma Super (1000 ml/ha), Topic (500 ml/ha), Derby Super (33 g/ha) + Puma Super (1000 ml/ha), Stretch (15 g/ha) + Puma Super (1000 ml/ha), in a single-weeded control and a non-weeded control. The aim of the study was to determine the influence of some herbicides and herbicide combinations on the weed density as well as on the productivity and yield elements of the winter wheat variety Sadovo 772.
The analysis of the results showed that greater percentages of broad leaved (90.0%) and grassy weeds (83.3%) were eliminated and the highest grain yield (5568 kg/ha) was recorded where Derby Super (33 g/ha) + Puma Super (1000 ml/
ha) were applied. Dery Super (33 g/ha) and Puma Super (1000 ml/ha) applied independently resulted in lower yields – 5422 and 4595 kg/ha, respectively. The lowest grain yield (3722 kg/ha) was obtained when the combination of Stretch (15 g/ha) with Puma Super (1000 ml/ha) was applied. All tested herbicides applied independently and the combination Derby Super (33g/ha) + Puma Super (1000 ml/ha) contributed to 5.4-27.7% higher yields as compared to the non-weeded control.
Keywords: winter wheat, weeds, herbicides, productivity, yield.