Evaluation of physico-chemical properties and nutritional value of kiwifruit from vine (Actinidia deliciosa var. Hayward) influenced by different preharvest fertilization methods during cold storage

In order to evaluate the effect of different preharvest fertilization methods on quantitative and qualitative characteristics of kiwifruit (var. Hayward) at postharvest stage, an experiment was conducted in a randomized complete block design with 8 treatments in four replications in Citrus and Sub-tropical Fruits Research Center during three crop years (2014- 2016). Fertilizer treatments included broadcast application (control), localized placement, strip, foliar, fertigation, broadcast application + foliar, fertigation + foliar and localized placement + foliar. Then in the first of November in each year, sampling of the treated fruits was carried out to measure the quantitative and qualitative characteristics of the fruit at postharvest stage during three years. Harvested fruits were kept cold storage at 0.5 ° C and 90% relative humidity for three months. The results showed, the fertilizer method had a significant effect on the fruits weight loss. So that the fruits fed by strip (6.08%), fertigation (6.74%) and combination of fertigation and foliar application (6.61 %) methods had less weight loss during cold storage, respectively. L * and chroma content of flesh were affected by the fertigation method. Result also showed that the control fruits had the lowest amount of antioxidant capacity and strip fertilization treatment had the highest antioxidant capacity during cold storage. Sensory attributes analysis showed that the amount of aroma, flavour, off-flavour, sweetness, sourness and overall fruit acceptability in fruits treated by broadcast application + foliar method obtained the most desirable scores.