Impact of fertigation regimes on yield and water use efficiency of Mango (Mangifera indica L.) under subtropical condition

A field experiment was conducted in drip irrigated orchard of mango variety Dashehari at experimental farm of CISH, Rehmankhera, Lucknow to evaluate the effect of different soil moisture and nitrogen levels on the yield, quality and water use efficiency (WUE). Soil moisture regimes consisted of four irrigation levels based on open pan evaporation replenishments (0.9, 0.7 and 0.6 OPE and one basin irrigation as control) and two fertigation levels of 75 and 50 per cent of the recommended dose of nitrogen with no N as control. The results revealed that the drip irrigation irrespective of fertigation levels significantly increased fruit yield over basin irrigation. Irrigation given to the replenishment of 60 per cent of USWB (United States Weather Bureau) Open Pan Evaporation was found to be statistically superior to 70 and 90 per cent replenishments. The increase in fruit yield in 0.9, 0.7 and 0.6 OPE was 19.4, 40.5 and 57.5 per cent respectively as compared to basin irrigation. The yield improvement in 0.6 OPE was higher to the tune of 32.0 and 15.5 per cent as compared to 0.9 and 0.7 OPE respectively. It was found that under the condition of limited water supply, drip irrigation proved consistently superior to the basin application; which significantly saved 15.0, 31.4 and 40.5 per cent of irrigation water in 0.9, 0.7 and 0.6 OPE, respectively as compared to control. The water use efficiency ranged between 9.9 to 18.8 kg fruits per m³ of water applied in the drip irrigation system as compared to 7.0kg fruits per m³ of water applied in basin irrigation.