Jujube (Ziziphus jujuba Mill.) belongs to Rhamnaceae (buckthorn family). Its cultivars were first imported into the United States by Frank N. Meyer from 1908 to 1918 (Meyer, 1916; Yao, 2013). Jujube is a deciduous fruit tree with more than 800 cultivars in China (Liu and Wang, 2009). A good estimate for jujube cultivars in the United States would be ≈100, most casually named and unclassified, often growing in people’s backyards. Commercially, ‘Li’, ‘Lang’, ‘Sugarcane’, ‘GA866’, ‘Sherwood’, and ‘Honeyjar’ are common, with ‘Li’ and ‘Lang’ being dominant, especially ‘Li’. ‘Li’ has round, large fruit and is precocious and productive. Its fruit eating quality is good, but it is not suitable for drying in most areas (Yao et al., 2019).
Jujube fruit size ranges from thumb to golf ball size depending on cultivar. First-time tasters usually compare the flavor of jujube to sweet apple or sweet pear. The dry jujube fruit tastes similar to a dry palm date. Dry jujube fruit and seeds from wild jujubes (Z. spinosa Hu) are popular traditional medicinal herbs in China. Approximately 60% of traditional Chinese medicinal prescriptions have dry jujube fruit in them, for its own medicinal value and for minimizing the toxicity of other herbs (Liu, 2008).
For people who have not tasted jujube fruit, the firm texture and sweet flavor of fresh fruit would be easier to accept than dry fruit. With cold storage technology, some cultivars can be stored for 2 months or longer depending on cultivar and maturation stage at picking (Chen et al., 2008; Li and Wen, 2008; Wang et al., 2008). Fresh jujube fruit have a high ascorbic acid (vitamin C) content, but 90% or more of it is lost during the sun drying process (Huang et al., 2017; Yao, 2013). Dry fruit have the advantage of multiple uses and easy storage. They can be stored for 1 year or more at room temperature or 2 to 3 years in cold storage, greatly extending the market season. Dry jujube fruit can be processed further as fruit slices/rings, wine, vinegar, drinks, or ingredients in cooking/baking or used for healthy component extraction or other value-added products (Guo and Shan, 2010). As jujube acreage increases, combined with the relatively short marketing period for fresh jujubes, drying or multipurpose cultivars (good for both fresh eating and drying) can provide more marketing choices for growers. Consumers also demand year-round jujube fruit supplies for different end uses.
‘Lang’ is known as a drying cultivar, but there is no study or publication on drying cultivars in the United States, except for a few sentences from a publication from the 1920s (Thomas, 1927). With this in mind, we included drying cultivars and multipurpose cultivars in our trials at three NMSU study sites: Alcalde (2015), Los Lunas (2015), and Leyendecker (2017) (Yao and Heyduck, 2018; Yao et al., 2019). We previously reported the early performance of fresh-eating and ornamental cultivars. Here, we evaluate the performance of drying and multipurpose cultivars.
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Yao, S., Heyduck, R. & Guldan, S. 2019 Early performance of fresh eating jujube cultivars in the southwestern United States HortScience 54 1941 1946 doi: 10.21273/HORTSCI14312-19