EFFECT OF HERBICIDES AND WHEAT POPULATION ON CONTROL OF WEEDS IN WHEAT

Field studies were undertaken at agricultural research farm, nwfp agriculture university peshawar during ‘rabi’ 2003-04 to investigate the effect of planting density and postemergence herbicides on wheat. the experiment was laid out in randomized complete block (rcb) design with split-plot arrangements. four seeding rates viz., 100,120,140 and 160 kg ha-1 were assigned to main plots, whereas herbicides to the sub-plots. the herbicides were topik 15wp (clodinafoppropargyl) @ 0.02, 2,4-d sodium salt 92%@ 0.90,isoproturon 75ew 0.63, puma super 75ew (fenoxaprop-p-ethyl)@ 0.75, agritop (mcpa) 500gl-1@ 0.43 and affinity 50wdg (carfentrazone-ethyl ester)@ 0.35kg ha-1. hand weeding and weedy check were also included for comparison. statistical analysis of the data showed that all the parameters were affected by different herbicides, while seed rates significantly affected the plant height at maturity. the interaction of seed rates with herbicides also showed significant effect on fresh weed biomass. topik 15wp treated plots exhibited the best performance with minimum weeds density (74.75m-2) and weed fresh biomass (1875kg ha-1) as compared to weedy check (387.3 m-2 and 5313 kg ha-1). maximum grain yield (3656 kg ha-1), number of tillers (215.6 m-2) and plant height (56.53 cm) at maturity were recorded in topik 15wp. affinity closely followed the topik in the studied parameters. thus topik 15wp and affinity 15wdg are recommended for controlling weeds in wheat.