The Clemson University Peach Breeding Program has recently released three bacterial spot (Xantomonas arbicola pv. pruni) tolerant peach cultivars: ‘CaroRes Wonder’, ‘CaroRes Delight’, and ‘EveRes Ruby’. Plant material from these early ripening genotypes was introduced to Auburn University in 2017 as advanced selections ‘SC-1’, SC-2’, and ‘SC-9’ and planted at the Chilton Research and Extension Center in Clanton, Alabama. Data is being collected to determine these cultivars’ productivity, disease resistance, and overall performance in Alabama conditions.

According to the breeder Ksenija Gasic, the ‘CaroRes Wonder’ cultivar requires about 500 chilling hours to break dormancy in spring. In central Alabama conditions, ‘CaroRes Wonder’ blooming starts in the second half of February to early March, and the fruit ripens mid- to late-May (figure 1).

During the 2024 season, a bacterial spot infection occurred in mid-May. Bacterial spot disease, also known as bacterial shothole, can affect leaves and fruit. Symptoms on leaves of ‘CaroRes Wonder’ appeared as numerous angular, purple to purplish-brown or black spots (figure 2). The heavily infected leaves of ‘CaroRes Wonder’ turned yellow and dropped prematurely. Light symptoms of bacterial spot infection—including tiny, water-soaked, and sunken spots—were observed on some of the fruit this season.

Harvesting of the ‘CaroRes Wonder’ fruit began May 20, 2024, when the average yield per tree was 17.0 pounds. The total yield produced per tree during the 2024 season was 124.1 pounds per tree. There were on average 454 fruit per tree harvested from ‘CaroRes Wonder’ in the spring. Data on the number of fruit and yield produced per tree at each harvest date is shown in table 1.

The average individual fruit weight of ‘CaroRes Wonder’ was 147.9 grams, the mean fruit diameter was 63.4 millimeters, and the total soluble solids (Brix) content was 11.1 percent (table 2). Fruit taste was excellent, with a juicy and firm flesh but was slightly acidic because of the frequent rain events during fruit ripening. Fruit appearance was attractive, with almost 100 percent blush cover (figure 3).