Effect of Pulverization Tools and Deficit Irrigation Treatments on Water Use Efficiency and Yield of Barley

Abstract

Under limited water resources in arid and semi-arid environments, the great challenge of developing agriculture is to increase water use efficiency. For that field experiment have been conducted during autumn season of 2011-2012 at the experimental farm, Department of Agricultural Machines Science, College of Agriculture –University of Baghdad. A field study have been carried out to determine the effect of pulverization tools and irrigation scheduling on growth parameters and Water Use Efficiency (WUE) of barley crop for optimum production. Pulverization tools treatments are (rotivator, disk harrow and spring cultivator). Deficit irrigation including omitting two irrigation at growth stage (T1), flowering stage (T2) and growth grain stage (T3), as well as the full irrigation treatment (control) (T0). Irrigation is applied at 55% depletion of available water. Plant growth parameter of barley is significantly affected by the different irrigation treatments and pulverization tools. The mean values of the pulverization tools shows that the plant height (cm) decreased from 86 to 79 and 76, No. of spike/ m2 from 582 to 569 and 530, biological yield (t/ha) from 16.64 to 16.13 and 14.72 and the grain yield (t/ha) from 5.36 to 4.81 and 4.22 at spring cultivator, disk harrow and rotivator, respectively. The deficit-irrigated treatments required less water than the control-irrigated treatments,have been recorded 320 – 369 mm and 373 – 411 mm, respectively. The mean ETa measured during the season is 370 mm for spring cultivator and 391, 400 mm for the disk harrow and rotivator, respectively. The highest actual evapotranspiration is measured for the rotivator + control irrigation treatment (438 mm), while the lowest value have been recorded 347 for spring cultivator + deficit irrigation (T3). The water use efficiency of all the treatment ranges from 0.94 to 1.53 kg m-3 while the irrigation water uses efficiency ranges from 1.01 to 1.66 kg m-3.