Effect of water deficit and fertigation on nutrients uptake and soil fertility of drip irrigated onion (Allium cepa L.) in semi-arid region of India

Water and fertilizers both are critical limiting factors that affect the agriculture production in arid and semi-arid regions of India. Crop productivity and nutrient use are mainly water restricted in semi-arid regions. This study was conducted to find out whether nutrient uptake by onion crop could be elevated through drip fertigation. A two years study was conducted on sandy loam soil at Chaudhary Charan Singh Haryana Agricultural University, Hisar (India) with the objectives to estimate the effect of deficit irrigation on soil fertility and nutrient uptake by crops using drip irrigation and nitrogen fertigation. The design of the experiment was split plot with drip irrigation in main plots and nitrogen fertigation in sub-plots. The main plot treatments consisted of four levels of drip irrigation, i.e., 60, 80, 100% and 120% CPE and sub-plot treatments consist of nitrogen fertigation scheduling, i.e., 75, 100, 125 and 150 kg/ha nitrogen at fifteen day interval. The drip irrigation at 100% CPE with five split of recommended dose of nitrogen (125 kg/ha) through fertigation enhanced the nitrogen (187.44 and 196.48 kg/ha, respectively), phosphorus (44.30 and 61.86 kg/ha, respectively) and potassium (211.83 and 226.68 kg/ha, respectively) uptake by onion plant as compared to other treatment combination in both years of the study. However, individual application of drip irrigation and nitrogen fertigation significantly affected the nutrients availability in soil after harvest, while the combined application of drip irrigation and nitrogen fertigation did not significantly influence by during both years.