Current advances in fresh-market muscadine breeding have yielded new perfect-flowered (self-fertile) cultivars with larger and more uniform berries, thinner skins, crisp flesh, and nonslip skins that adhere to the flesh. Cultivars ‘Lane,’ ‘Hall,’ ‘Paulk,’ and ‘Ruby Crisp’ were developed by the muscadine grape breeding program at the University of Georgia. These cultivars are among the new releases that have improved biological traits and fruit quality attributes. ‘Razzmatazz’ is another muscadine and European (V. vinifera) grape hybrid cultivar that was released from a private breeding program. ‘Razzmatazz’ produces sweet, seedless berries that have a thin skin and crisp flesh.

Research at the Chilton Regional Research and Extension Center

Figure 1. Clusters of ‘Razzmatazz’ seedless muscadine grapes grown in 2023.

An experimental vineyard of these newly released, self-fertile muscadine grape cultivars was established at the Chilton Regional Research and Extension Center. The purpose of this research was to evaluate the performance of these cultivars that have improved qualities in Alabama growing conditions and provide recommendations on muscadine-cultivar selection to farmers and home-garden enthusiasts. The ‘Supreme’ cultivar was included as a control in this trial. Vines were planted at 12 feet by 20 feet and trained to a high-wire bilateral cordon system in 2019.

‘Razzmatazz’

The first commercial crop was harvested in 2022. ‘Razzmatazz’ clusters matured about 2 weeks earlier than other cultivars in 2023. ‘Razzmatazz’ is a muscadine and V. vinifera hybrid with seedless berries that mature uniformly on a small cluster. ‘Razzmatazz’ is self-fertile (no need to be pollinated in order to produce a good crop), continuously fruits along the shoot, and a highly disease-resistant cultivar. During the 2023 season, ‘Razzmatazz’ clusters started to mature at the end of July. The first ‘Razzmatazz’ harvest occurred July 28 (table 1), and cluster picking continued for 4 more weeks, until August 30. The total ‘Razzmatazz’ yield was 32.6 lb/vine. The average number of clusters harvested per vine was 126, with a mean cluster weight ranging from 34 to 48 grams. Clusters have an attractive deep red color (figure 1). The average berry weight was 1.5 grams, and the mean total soluble solids content was 17.9 percent.

‘Lane’

‘Lane’ is a self-fertile, early season ripening black cultivar. The first ‘Lane’ harvest in 2023 occurred August 16, when 21.3 lb/vine were picked (table 2). ‘Lane’ berries continued to mature until October 11 and produced a total yield of 35.0 lb/vine. ‘Lane’ berries were relatively large (9.0 grams) but smaller than ‘Supreme’ (14.7 grams). ‘Lane’ has moderate vine vigor and sweet (16.9 percent total soluble solids), attractive (figure 2a) berries that have a tendency to split and tear during picking. According to the breeder, the ‘Lane’ cultivar’s firm flesh prevents leakage.

‘Hall’

‘Hall’ is also a self-fertile, early season, and productive muscadine cultivar. Berries were harvested weekly from mid-August to mid-October in 2023, when the total yield was 66.4 lb/vine (table 2). This yield was similar to the yield of the control cultivar, ‘Supreme.’  The average individual berry weight of ‘Hall’ was 10.2 grams, and the berries were sweeter (17.1 percent sugars) than the control (14.6 percent sugars). ‘Hall’ berries had the highest percent dry berry stem scar (91.3 percent), which can facilitate a longer shelf life and reduced leakage. The large berries of ‘Hall’ also have an attractive bronze color (figure 2b) that consumers in the Southeast prefer to enjoy.

‘Ruby Crisp’

The first crop of ‘Ruby Crisp’ began to mature in late August. This mid-season, self-fertile cultivar produced on average 36.1 lb/vine (table 2), similar to ‘Lane.’ ‘Ruby Crisp’ berries have a firm flesh and tender nonslip skin, which makes this cultivar more similar to European (Vinifera) table grapes. ‘Ruby Crisp’ berries are large (13.0 grams on average in 2023) and have a high total soluble solids (16.3 percent), good taste, distinct red color (figure 3a), and an attractive appearance. The percent wet stem scar of ‘Ruby Crisp’ (19.8 percent) was higher than ‘Hall’ but lower than ‘Paulk’ this season.

‘Paulk’

‘Paulk’ is another self-fertile, mid-season cultivar that yielded 43.8 lb/vine on average (table 2). The berries are large, with an average weight of 14.2 grams, which is similar to the ‘Supreme’ average weight (14.7 grams). ‘Paulk’ berries were significantly larger than the other self-fertile grapes in the research. Total soluble solids recorded this season were 15.9 percent, and the wet stem scar was 32.6 percent, the highest among tested cultivars.