ECONOMIC ANALYSIS OF DRIP‐IRRIGATED KINNOW MANDARIN ORCHARD UNDER DEFICIT IRRIGATION AND PARTIAL ROOT ZONE DRYING

Abstract

ABSTRACT The profitability of regulated deficit irrigation (RDI), sustained deficit irrigation (SDI), and SDI with partial root zone drying (PRD) strategies was compared to that with full irrigation (FI: 100% crop evapotranspiration) in drip‐irrigated Kinnow mandarin in northern India. RDI was scheduled with two irrigation levels: no irrigation and 50% crop evapotranspiration (ETc.) imposed in the early fruit growth period (EFGP) and final fruit growth period (FFGP) singly and in combination, whereas SDI was scheduled at 50% ETc and 75% ETc with and without the PRD technique. The highest fruit yield was recorded with FI, which was statistically on a par ( p > 0.05) with that with SDI at 50% ETc with PRD (PRD 50 ). Economic‐based comparison shows that all the treatments were economically viable since their profitability (net return, INR 137 000–1 300 000 ha ‐1 and benefit–cost ratio, 2.1–14.3) were viable. The net return generated with PRD 50 was statistically ( p > 0.05) at par with that generated with FI. However, the benefit–cost ratio and economic water productivity calculated with PRD 50 were found to be significantly ( p < 0.05) higher (36 and 87%, respectively) than that with FI. These results lead us to conclude that the PRD 50 strategy could be used to improve irrigation water productivity substantially in commercial Kinnow mandarin orchards in sandy loam soil. Copyright © 2013 John Wiley & Sons, Ltd.