Efficacy of Oxadiargyl Reduced Doses for the Control of Weeds in Potato (Solanum tuberosum) with Different Application Timing

In order to study the effect of reduced doses of oxadiargyl, on weeds control in potato, a field experiment was conducted at Alaroog Research Station in Ardabil during 2013. Experiment arrangement was factorial based on randomized complete blocks design with three replications. First factor included seven reduced dosages of oxadiargyl (0, 0.05, 0.1, 0.2, 0.4, 0.6, 0.8 L a.i/ha) and second factor included oxadiargyl application timing (potato emergence, stoloning and tuber bulking). The results showed that application of 0.8 L a.i/ha of oxadiargyl reduced weed density and biomass to 48.40 and 66.16 percent, respectively which was not significantly different from applying 0.6 L a.i/ha. Maximum reduction percentage of weed density and biomass on the different potato growth stages was at potato emergence stage, which provided the best effectiveness of the oxadiargyl. On the other hand, application of 0.8 L a.i/ha oxadiargyl at potato emergence stage caused the highest mean of tubers weight per plant and total tuber yield, but was not significant on the tuber number per plant.