Effects of Harvesting Time and Girdling Methods to Branches on Fruit Quality of Kiwifruit ‘Amawi’.

Abstract

The effects of harvesting time and girdling methods on fruit quality of kiwifruit ‘Amawi’ (Actinidia chinensis (Planch.) var. chinensis) were analyzed. Four independent harvest surveys in the five orchards showed soluble solids concentration at harvest reached around 9% from October 28 to November 4 in 2021, and after ripening it also tended to increase as the harvest period was delayed. The h-value of flesh color after ripening tended to decrease as the harvest period was delayed, and the h-value was below 100 in October 28, and the fruit color improved from green to yellow. There was a negative correlation between the accumulated temperature under the trellis from the day of full bloom to the harvest date and post-ripening flesh color, with the flesh color h value reaching 100 when the accumulated temperature reached approximately 3,800°C. In addition, when a one cm-wide girdling method was applied to the base of major or lateral branches at the beginning of September, the post-ripening flesh color tended to turn yellow compared to the non-treated area. These results suggested that harvesting after sixth half of October and applying girdling methods are effective in improving fruit quality of ‘Amawi’.