Effect of Different Methods of Chemical Weed Control Irrigation Regimes on Weed Biomass and Safflower Yield

In order to investigate the effects of different weed control methods and moisture regimes on safflower (Carthamus tinctorius), a field split plot experiment based on randomized complete block design with 4 replications was conducted in Takestan Iran, during growing seasons of 2007-8. Three irrigations regimes (normal irrigation, restricted irrigation at stem elongation and restricted irrigation at flowering stage) were assigned to the main plots and nine chemical weed control method (complete hand weeding, treflan with 2 L/ha as pre plant herbicide, sonalan with 3 L/ha ad pre plant herbicide, estomp with 3 L/ha as pre plant herbicide, gallant super with 0/75 L/ha as post emergence herbicide, treflan with 2 L/ha as pre plant herbicide gallant super with 0/75 L/ha as post emergence herbicide, sonalan with 3 L/ha as pre plant herbicide gallant super with 0/75 L/ha as post emergence herbicide estomp with 3 L/ha as pre plant herbicide gallant super with 0/75 L/ha as post emergence herbicide and without hand weeding) to sub- plots. At the end of growing period traits like number of head per plant, number of seed per head, 1000 grain weight, percent of seed oil, yield of seed oil and grain yield were measured. Results indicated that treflan gallant super treatment in restricted irrigation at stem elongation stage had the lowest dry weight of weeds. In this study maximum grain yield (2927 Kg/ha) was achieved from hand weeding usual irrigation treatments. In general treflan gallant super treatment was the most effective treatment on safflower yield and weed control.