Deficit irrigation strategies of flat peach trees under semi-arid conditions

Abstract

In a context of severe water scarcity and high uncertainty of available irrigation water, the sustainable management of irrigation inputs to the crop has become necessary. The main objective of the present study was to determine the mid-term effect of water restrictions using different plant water status indicators of yield and quality of flat peaches. Two treatments were tested: (i) control (CTL), irrigated at ∼100% of crop evapotranspiration (ETc) during the entire season; and (ii) a regulated deficit irrigation (RDI) treatment, irrigated as the CTL, except during the second fruit growth stage (∼70% ETc) and late post-harvest (∼50% ETc), with the same fertilization as CTL. In the first and second water deficit periods, an average weekly reduction of 43 and 109 m3 ha–1 was achieved, respectively. This resulted in water savings of 33.6% in the RDI treatment with respect to well-irrigated trees and an increase in the irrigation water productivity of 45%, reaching values of around 4.16 kg m–3. Therefore, the optimization of irrigation water inputs in semi-arid conditions was achieved, by considering that the post-harvest period in this crop is a non-critical phenological period, with a stem water potential (Ψs) threshold value of around −1.4 MPa. Multiple regression models were obtained as irrigation thresholds based on Ψs for well- and deficit-irrigated trees.

Keywords

• Stone fruit
• Water scarcity
• Water stress integral
• Irrigation protocols
• Irrigation water productivity