Effect of tillage system and deficit irrigation on consumptive use, some soil physical properties, growth and yield of potato Solanum tuberosum L

The experiment was conducted to estimate the crop water requirement and water use efficiency of potato under complete and deficit irrigation with two tillage systems. The study was carried out in field of Agricultural Collage- University of Baghdad during spring season 2013. Split plot design under Randomized Complete Block Design with three replicates was used in this study. The first factor Tillage systems included Mold Board Plow and Chisel Plow. Whereas the second one was irrigation treatments included (full irrigation T0), irrigation imposed at 35% depletion of available water, the deficit irrigation (cutting one irrigation) in differ stage of plant growth include: no irrigation during vegetative growth stage (T1), no irrigation during tuberigation stage (T2), no irrigation during bulking and tuber enlargement (T3). All agricultural processes for crop management were used according to Ministry of Agriculture recommendation. Actual evapotranspiration was estimate using water balance equation. Some soil physical properties determine after a month of Agriculture, mid-season and after harvest included soil bulk density, saturated hydraulic conductivity and mean weight diameter. Also some plant properties measured included: high of plant (cm), number stems/plant, leaf area (cm2/plant), number of tubers per plant and potato yield (kg. h-1). The actual evapotranspiration (ETa) values of complete irrigation were 400 and 436 mm for Mold board plow treatment and Chisel plow treatment, respectively. The highest WUEf value was obtained from T1 treatment (deficit irrigation at vegetative stages) with average of 11.6 and 8.8 kg m-3 for mold board plow and chisel plow, respectively. The value of high plant, number stems/plant, leaf area, number of tubers per plant and potato yield recorder 62.45;43.05 cm, 4.41;3.89 stems/plant, 8850;6046 cm2/plant, 6.74;4.58 tubers per plant and 2896;2496 kg. h-1 for mold board plow and chisel plow treatment, respectively.