Long-term productivity of early season peach trees under different irrigation methods and postharvest deficit irrigation

Authors: Wang, Dong; Zhang, Huihui; Gartung, Jimmie

Submitted to: Agricultural Water Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/27/2019
Publication Date: 11/27/2019
Citation: Wang, D., Zhang, H., Gartung, J.L. 2019. Long-term productivity of early season peach trees under different irrigation methods and postharvest deficit irrigation. Agricultural Water Management. 230. https://doi.org/10.1016/j.agwat.2019.105940.
DOI: https://doi.org/10.1016/j.agwat.2019.105940

Interpretive Summary: Deficit irrigation has long been recognized as a means of water savings for crop production but its long-term impact on crop productivity is unknown. Over a 10-year period, this study investigated the long-term effect of deficit irrigation and different methods of irrigation on peach production. Up to 40% water savings was achieved with deficit irrigation for 8-9 years while fruit yield and quality were not significantly impacted. In general, no difference was found on fruit yield or quality between different methods of irrigation. The research findings highlight the unrealized potential of deficit irrigation as an on-farm management strategy in greatly increasing water use efficiency.

Technical Abstract: Water shortage has been a major concern for crop production in the Western U.S. and other arid and semi-arid regions in the world. Deficit irrigation can be used as a potential water saving strategy to alleviate water shortage, however, the long-term impact on productivity is unknown. For early-maturing peach varieties, it has been demonstrated that established orchards are not sensitive to moderate water stress in the non-fruit bearing postharvest growth periods. A 10-year long field study was carried out to compare effects of furrow, drip, and micro sprinkler irrigation under either full irrigation or postharvest deficit irrigation treatments on peach tree health and fruit yield and quality. In the first 3 years of the experiment, trees under full irrigation grew faster which led to lager trunks than trees under deficit irrigation. At the end of the study, tree canopy size showed no difference among different methods of irrigation or between full and deficit irrigation. There was also no treatment effect on leaf photosynthetic rate or stomatal conductance among different irrigation treatments. Deficit irrigation of up to 40% water savings did not lead to significant yield losses for 8-9 years. Deficit irrigation also did not cause a significant reduction in fruit quality except for an increase in percentage of double fruits but the worst year case was still less than 1.5%. The study demonstrated the feasibility of applying continued postharvest deficit irrigation for up to10 years for peach production which resulted in significant water savings during the summer peak water use period.