Kiwifruit Cultivars Differ in Response to Winter Chilling

Abstract Cuttings from five cultivars of [Actinidia deliciosa (A. Chev.) C.F. Liang et A.R. Ferguson var. deliciosa] were excised following ambient exposure to chilling temperatures in 100 hour accumulated increments. Cuttings were then placed in a thermostatically controlled greenhouse maintained at 72°F (22.2°C) for forcing to determine effects of chilling on flower buds and vegetative growth. Our data indicate 'Matua' and 'AU-1M' are better pollinizers than Tomuri' based on flower uniformity per stem, the number of flowers per stem and the total number of flowers remaining at the end of the study. Stem length and leaf area, providing indicators of overall plant vigor, were always greater for males than female cultivars. Our data indicate 'AU-1F' could potentially set more fruit than 'Hayward' based on stem uniformity of flowering, flowers per stem, and flower retention. Key Words: Actinidia deliciosadormancyvegetative budfloral budreproductive meristemrest