Performance of Apple (Malus ×domestica Borkh.) Cultivars Grown in Different Chilean Regions on a Six-year Trial, Part I: Vegetative Growth, Yield, and Phenology

Abstract

Performance of seven apple (Malus ×domestica Borkh.) cultivars (‘Brookfield®Gala’, ‘Galaxy’, ‘Super Chief’, ‘Granny Smith’, ‘Fuji Raku Raku’, ‘Cripp's Pink’, and ‘Braeburn’) on M.M.106 and M.9 EMLA rootstocks during their first 6 years was evaluated on a multisite trial in Chile. Second-leaf trees were planted in experimental blocks inside commercial orchards located in five major apple-producing areas in Chile (Graneros, San Clemente, Chillan, Angol, and Temuco). Tree height and volume, trunk cross-sectional area (TCA), fruit yield and size distribution, crop load, and tree phenology were assessed annually. In general, tree growth rates by the end of the third year, when they reached the desired height, were similar in all block locations. M.9 EMLA rootstock reduced tree height by ≈20% in ‘Brookfield® Gala’, ‘Fuji’, ‘Galaxy’, and ‘Granny Smith’. This rootstock also had 50% smaller TCAs than M.M.106’s at Year 6 in most cultivars. The highest productions in ‘Brookfield®Gala’, ‘Galaxy’, ‘Granny Smith’, ‘Cripp's Pink’, and ‘Super Chief’, regardless of rootstock, were obtained in San Clemente and Chillan's blocks. Although M.M. 106 trees delivered higher yields per plant, M.9 EMLA yield efficiency (no. fruit/cm2 TCA) was significantly higher. In general, the higher the latitude (toward south), the later budbreak, full bloom, and harvest occurred.