Effect of glyphosat and paraquat herbicides on weed control and productivity of cotton

Weed control management has a vital role in increasing cotton yield and yield components. In cotton crop weed, infestation may harm significant growth and yield loses. To control the weeds under field conditions in cotton crop, different herbicides were selected with different dose levels. Response of various post emergence herbicides at different levels, i.e. Round up 490 G/L at the rate of 4.7 L ha-1, 2.7 L ha-1 and 1.5 L ha-1 (Glyphosate), Gramoxone 20EC (Paraquat) at the rate of 2.5 L ha-1 and untreated (Control) were field experimented against cotton cultivar CIM-473 under field condition at Agronomic Research Area of Central Cotton Research Institute (CCRI) Multan, Pakistan. Significant control of weeds, i.e. number of weeds m-2, fresh weed biomass in g m-2, dry weed biomass in g m-2 and increase in yield and yield contributing factors, like number of bolls plant-1, cotton boll weight (g), final cotton plant height (cm) and seed cotton yield (kg ha-1) were observed. The field data for weed control in term of numbers, fresh and dry weight was observed after 10, 20 and 30 days of sowing. It was indicated that the highest significant yield, total number of bolls per plant, fresh weed biomass, dry weed biomass, plant height and weed control were obtained by using herbicide Round up (Glyphosate) at the rate of 4.7 L ha-1, as compared to the other treatments with different application rates including untreated (control). Average boll weight was not significant among treatments, but significant against control. Cost benefit analysis showed that the highest net profit was obtained by the Round up 490 G/L, when treated @ 4.7 L ha-1 than all other treatments