Sustainability of regulated deficit irrigation in a mid-maturing peach cultivar

• Published in: Irrigation science 2016-05, Vol.34 (3), p.201-208
• Main Authors: Marsal, Jordi, Jaume Casadesus, Gerardo Lopez, Merce Mata, Joaquim Bellvert, Joan Girona
• Format: Article
• Language: English
• Subjects: Agriculture; Aquatic Pollution; Biomedical and Life Sciences; Climate Change; Cultivars; deficit irrigation; Environment; Fruits; Gold; Irrigation; irrigation rates; Life Sciences; Original Paper; Peaches; Prunus; raw fruit; Seasons; Stresses; Sustainability; Sustainable agriculture; Sustainable Development; Thresholds; Waste Water Technology; Water Industry/Water Technologies; Water Management; Water Pollution Control; Water potential
• ISSN: 0342-7188; 1432-1319
• DOI: 10.1007/s00271-016-0498-4

The level of irrigation restriction to apply in a deficit irrigation (DI) programme for sustainable peach (‘Baby gold 6’) production was investigated. The experiment involved four irrigation treatments over five consecutive seasons (2007–2011). They were full irrigation (control), reducing irrigation by 20 % during the first half of stage III (DI-80 %), withholding irrigation until reaching a light stress level (DI-L) and withholding irrigation until reaching a moderate stress level (DI-M). The withholding of irrigation in both DI-L and DI-M was applied only during stage II and postharvest periods and was based on midday stem water potential thresholds (Ψ ₛₜₑₘ). For the DI-L treatment −1.5 MPa was used in both periods, and for DI-M −1.8 and −2.0 MPa were used during stage II and postharvest, respectively. Average Ψ ₛₜₑₘ values during DI periods were approximately −1.4 and −1.2 MPa for DI-M and DI-L, respectively. The pre-defined thresholds required to trigger irrigation were rarely reached. No significant differences between treatments were found in terms of yield in any experimental year. However, DI-M and to a lesser extent DI-L had lower final fruit fresh mass at harvest related to lower Ψ ₛₜₑₘ after three consecutive years of the experiment (during 2010 and 2011). Therefore, in terms of fruit size, DI was not sustainable. Rather than lowering Ψ ₛₜₑₘ thresholds, we recommend discontinuing DI after 3-year application.