Effect of Added Weights on Tractor Rear Tires and Soil Moisture Content on Some Indicators of Mechanical Unit Performance During Moldboard Plowing

The study was conducted to find out the effect of adding weights on the wheels of the agricultural tractor and soil moisture content using the moldboard plow by measuring some mechanical properties, including the drawbar power,fuel consumption, soil bulk density , irregularity index of tillage depth as a percentage and the soil disturbed volume in the cultivation season (2017-2018)in one of the agricultural fields with soil of clay texture which is located in the northeast of Mosul city. and the texture of the soil was clay the field was divided according to a split plot arrangement under Randomized Complete Block Design with three replications. The results of the study showed that the soil moisture content (14-16)% achieved fewer values for drawbar power, fuel consumption, irregularity index of tillage depth as a percentage and soil bulk density and the higher values for soil disturbed volume, while, the adding weights on tractor wheels of (310)kg gave the less values for drawbar power, fuel consumption, soil bulk density and Irregularity index of tillage depth as a percentage and higher values for treated soil volume, also the interaction between the soil moisture content (14-16)% with adding weights on tractor wheels (310)kg achieved the less values for each drawbar power, fuel consumption, soil bulk density and Irregularity index of tillage depth as a percentage, and the higher values for soil disturbed volume .