Consumptive Use, Water Use Efficiency, Moisture Depletion Pattern of Wheat under Semi-arid Eastern Plain Zone of Rajasthan

Background: India has the largest area under wheat cultivation but variability in climate is one of the major environmental threat to agriculture particularly wheat crop. The growth and yield of wheat crop is adversely affected by environmental stresses such as soil moisture deficit, high temperature, low light intensity etc. Among these stresses irrigation water is a scare resource, it’s optimization is fundamental to water resources use. It permits better utilization of all other production factors and thus leads to increased yields per unit area and time. The higher requirement of food to feed the increased population with reduced water availability for crop production forces the irrigation researchers and managers to use water-saving irrigation strategies to improve the water productivity (WP) in recent years. Thus, an assessment of the potential for reducing water needs and increasing production is the need of time. The current study aimed to study of this province in order to manage and control related problems. 
Method: In this context a field experiment was conducted during Rabi season 2016 and 2017, Soil moisture studies were started right from sowing and continued up to maturity of wheat crop. The soil moisture content under all the treatments of three replications was determined just before irrigation and twenty four hours after irrigation from 0-15, 15-30, 30-45 and 45-60 cm soil depths and calculate consumptive use of  water, soil moisture depletion pattern and water use efficiency. 
Result: Results revealed that the maximum consumptive use (350.01 mm) of water found with irrigation schedule at 1.2 ETc and highest water use efficiency (15.32 kg ha-1 mm-1) obtained with irrigation schedule at 1.0 ETc. Among the different wheat cultivars Raj-4120 registered higher consumptive use (332.57 mm) and Raj- 4238 obtained highest water use efficiency (16.13 kg ha-1 mm-1) while crop sown on 15th November recorded higher consumptive use (333.04 mm) and water use efficiency (15.69 kg ha-1 mm-1). Wheat is a surface feeder with fibrous root system, the maximum amount of moisture was depleted in shallow depth (0-15 cm) than deeper layers of soil.