A Navel Orange Variety Trial for the Desert Citrus Industry

A navel orange (Citrus sinensis L. Osbeck) trial was established at the University of Arizona Citrus Agriculture Center, Waddell, AZ in March 1999. This trial consists of the following selections: ‘Beck-Earli’, ‘Cara Cara’, ‘Chislett’, ‘Fisher’, ‘Fukumoto’, ‘Lane Late’, ‘Powell’, ‘Spring’, ‘Washington’ and ‘Zimmerman’, all on Carrizo citrange rootstock. ‘Washington’ is the standard cultivar selection for the local industry. Yield, packout and fruit quality data have been collected since the first harvest in 2001. ‘Fisher’, ‘Lane Late’, ‘Beck-Earli’ and ‘Washington’ have had the greatest 7-year cumulative yield, and those selections as well as ‘Cara Cara’ had good annual yields in 2007-08. ‘Beck-Earli’, ‘Chislett’, and ‘Lane Late’ generally have had large fruit size over the course of the experiment. ‘Beck-Earli’ has had characteristically elongated fruit, while the rest of the selections have had more rounded fruit. Among the early-harvest fruit, ‘Fisher’ is the least colored, and ‘Fukumoto’ colors the best. Spring’ fruit has the best color among those selections harvested late. ‘Cara Cara’ fruit typically has had the highest level of solids, while the late navels have lower levels of solids. Peel thickness and granulation of the selections varies depending on the year. Based on the data collected so far, ‘Beck-Earli’, ‘Cara Cara’,  ‘Fisher’, ‘Fukumoto’ and ‘Lane Late’ appear to be suitable alternatives to ‘Washington’ in the desert.