Deficit irrigation in nectarine: Fruit quality, return bloom and incidence of double fruits

Abstract

Deficit irrigation (DI) at phenological stages less sensitive to water stress (pit hardening and post-harvest stage) influenced fruit quality, plant growth, return bloom and incidence of double fruits in nectarines. Four irrigation levels: control irrigation (CI), DI 75 (75 % of CI), DI 58 (58 % of CI) and DI 33 (33 % of DI) were applied in ‘Spring Bright’ and ‘Summer Bright’ nectarines during pit hardening and post-harvest stages. DI 58 and DI 33 treatments resulted in development of intense red fruit colour and early maturity in ‘Spring Bright’. DI 33 improved fruit colour in ‘Summer Bright’, soluble solids concentrations (SSC) and SSC/acid ratio in both cultivars. DI 33 treatment decreased glucose and fructose at harvest in ‘Spring Bright’ and increased glucose in ‘Summer Bright’. DI 58 and DI 33 treatments improved the levels of total phenolics, antioxidant capacity, ascorbic acid and carotenoids in the fruit of both cultivars with acceptable fruit weight in comparison to CI. DI 33 treatment significantly increased the total anthocyanin content in fruit peel and reduced water sprout length in both cultivars. In subsequent season, the DI 58 and DI 33 treatments increased flower density in ‘Spring Bright’ and incidence of double fruit in either cultivar. Conclusively, DI improved fruit colour, SSC/acid ratio and nutraceutical levels; and reduced water sprout length. Further, it increased flower density and double fruits in the subsequent season.