EFFECTS OF TILLAGE PRACTICES AND SOWING METHODS ON WEEDS AND BIOLOGICAL YIELD OF WHEAT UNDER SEMI-ARID ENVIRONMENT

Field experiments were conducted at the New Developmental Research Farm, University of Agriculture Peshawar, Pakistan during the year 2009-2010, and were repeated in 2010-2011 to find out the effects of tillage practices and sowing methods on wheat production and its associated weeds. Experiments were established using a randomized complete block design with split plot arrangements and each treatment being replicated four times. Tillage treatments consisted of five farmers practices (tine cultivator twice - TC-2, tillage implements chisel plow + rotavator - CR, mouldboard plow + rotavator - MR, disc plow + rotavator - DR and tine cultivator + rotavator - TCR) and assigned to the main plots. Three sowing methods (broadcasting -BC, single box seed drill - SD and combined drill - CD) were used and assigned to the sub plots. Analysis of the two years mean data revealed that tillage practices had a significant influence on weed dry biomass and biological yield of wheat crop. Similarly, sowing methods had also a significant effect on biological yield of wheat crop. The least weed dry biomass (95 g m^-2) was recorded for plots plowed with MR tillage equipment followed by DR tillage equipment 9104 g m^-2). The greatest biological yield (10.4 t ha^-1) and plant height of wheat (105 cm) were recorded for MR tillage practices followed by DR, TCR and CR. Wheat crop sowing by drill method produced the maximum biological yield as compared to broadcast method. MR and DR tillage practices resulted 51 and 46% reduction in weed dry biomass, respectively as compared to TC-2. Therefore, to achieve efficient weed control and gain maximum biological yield of wheat, MR tillage practices should be adopted in semi-arid environments.