Rainwater harvesting and its efficient utilization in mandarin (Citrus reticulata Blanco) orchards under a dry sub-humid tropical climate

Water stress is a major factor affecting the productivity of citrus. Conservation and efficient use of rainfall–runoff may be an option for sustainable citriculture in water-scarce regions. A study, therefore, was conducted to evaluate the techno-economic feasibility of rainwater management strategies in citrus orchards of a water-scarce region of central India. The following three management strategies, namely (1) a continuous trench between plant rows (CTPR), (2) CTPR + rain water harvesting tank (RWHT)-based surface irrigation (IS), and (3) CTPR + RWHT-based solar-powered drip irrigation (ISD) were compared with rain-fed treatment (RFT) in citrus. Annually, CTPR + RWHT-based ISD conserved 4,556 m3 water ha−1, and resulted in higher fruit yield (219%), water productivity (85%), net profit (298%), net economic water productivity (130%), sustainable yield index (49%) and energy use efficiency (87%) compared with the RFT (fruit yield, 7.14 t ha−1; water productivity, 1.88 kg m−3; net profit, INR 59,704 ha−1; net economic water productivity, INR 15.75 m−3; sustainable yield index, 0.59; energy use efficiency,1.02 MJt−1) in citrus. The water balance of WHT indicated that 47% of harvested water could be utilized for irrigation in orchards. Overall, efficient rainwater management is suggested for citrus cultivation in water-scarce regions.