Effect of false seedbed and sowing density of different winter wheat cultivars on rye (Secale cereale L.) control and yield of winter wheat (Triticum aestivum L.)

To evaluate the effect of false seedbed preparation on rye (Secale cereale L.) control, an experiment was conducted during 2013 in Shahrekord. Experimental factors were arranged in split plot factorial design with three replications. The main plots included seed bed preparation at three levels: 1. conventional dry cultivation of wheat, 2. seedbed preparation, irrigation, weed control (including rye) with paraquqt (20% SL) at 2 L ha-1 after one month, wheat cultivation, 3. seedbed preparation, irrigation, mechanical weed control (using harrow), wheat cultivation. Subplots 1. included cultivars at three levels (Alvand, Pishgam and Back Cross Roshan) and 2. planting densities at three levels (200, 250 and 300 kg ha-1). According to the mean comparison, density and biomass of rye in the treatment of irrigation application of herbicide decreased relative to dry cultivation by 67.7 and 74.9 percent, respectively, Pishgam cultivar decreased rye density and biomass by 36.9 and 18.7 percent, respectively. The seeding rate of 200 kg ha-1 of wheat reduced density and biomass of rye by 24.3% and 22.4%, respectively. The highest grain and biological yield of wheat was observed in irrigation and application of paraquat with 4206 and 8872.3 kg ha-1, respectively. Based on the results of this research, for weed control, especially rye, yield and yield components of winter wheat, the best method of seedbed preparation, is false seedbed preparation using chemical control of weeds. The best wheat cultivar, was Pishgam and best wheat seeding rate, was 200 kg ha-1.