The University of Florida blueberry breeding program supports Florida blueberry producers, primarily through the development of new cultivars with improved yield, timing, disease/pest resistance, fruit quality, and flavor. In addition, the breeding program collaborates with and supports blueberry-related research in plant pathology, entomology, pollination, and production practices. The following are summaries of projects that are currently underway, to keep our producers up to date with the different levels of research occurring in the breeding program, and in collaboration with several UF/IFAS experts.
Disease and insect scouting guide phone app: As previously reported, we have been developing a Florida-specific scouting guide phone app, in coordination with other UF blueberry researchers. This tool will assist Florida growers with field diagnosis of disease, insect, and other blueberry plant damage, with a diagnostic key, symptom descriptions, images, and links to UF extension publications. After several delays due to software development issues, we expect the scouting app to be released by the end of this year. While we expect this to be a valuable tool for field scouting, we continue to recommend that producers contact the UF/IFAS plant pathologist and entomologist, and send samples to the UF/IFAS Plant Diagnostic Center to diagnose major issues.
2020 end of season data: Doug Phillips, our Blueberry Extension Coordinator, has been visiting commercial blueberry growers across the state this summer, gathering data on cultivar performance, disease and insect issues, pollination issues, etc. A summary of this information will be presented at the Florida Blueberry Growers Association virtual fall meeting, so growers can be aware of cultivar performance and production issues encountered in their region of the state. The survey also includes information about the challenges faced by blueberry producers from COVID-19 during the 2020 season, which will hopefully help us to be better prepared for any similar situations in the future.
Central Florida cultivar trials: Our southern highbush cultivar trial in Central Florida is now 2 years old, and we are continuing to monitor performance. The trial has 15 different southern highbush cultivars in two blocks, one with and one without hydrogen cyanamide application in the winter, to evaluate performance under both a deciduous and an evergreen system. We will use this trial for field day demonstrations when we are able to physically meet in large groups again.
Early selection test sites for evergreen production: A significant number of growers in South and Central Florida have been replanting with new cultivars and managing for evergreen production, taking advantage of mild Florida winters and better early prices. To support this trend, the breeding program has been increasing its efforts to select new and improved cultivars for this system. While many cultivars have been proven to work well in this system, extended ripening is still a disadvantage for utilizing machine harvesting, which is one of the traits we are now focusing on for evergreen production systems. We continue to plant early breeding materials in South-Central Florida, to select for blueberry plants that will perform well in the evergreen system in central and south-central Florida. Three promising elite evergreen selections were made this season, and will be grown out as advanced selections in multiple trial sites across the state.
New production system to maximize profitability: Substrate production (i.e., soilless or container production) is trending globally. While it involves a higher investment, this intensive production system has been shown to be promising in several respects, and thus could prove to be more profitable. Together with Dr. Gerardo Nuñez, and in collaboration with Straughn Farms, we have established a large substrate experiment where we are testing different substrate mixes, pot sizes, and plant architectures. The results of this experiment during the first and second year were above expectations. We have learned a significant amount of information about this new system, and are working toward publishing the results and making recommendations for production using this system. Yang Fang, a PhD student in the blueberry breeding program, is the project leader and will be talking about this project and recommendations at the Florida Blueberry Growers Association virtual fall meeting.
Increasing blueberry consumption by developing better tasting fruit: Flavor has been proven to be one of the most important traits for consumers. By improving flavor, we can benefit the entire production chain by impacting consumer liking, potentially increasing the frequency of blueberry purchasing. There has been a significant effort in this area for a long time in the breeding program. With the information collected over the years, we now have a much better understanding of the components that control consumer blueberry liking, and are incorporating this information into the selection process.
Hydrogen cyanamide dosage: In collaboration with Dr. Jeff Williamson, we are conducting an experiment to determine the appropriate level of hydrogen cyanamide to be applied to the recently released cultivars “Optimus” and “Colossus.” This is due in part to observations of decreased performance during 2018 in these cultivars, which appears to be related to hydrogen cyanamide issues. Small differences across treatments using different doses were observed in 2019 and 2020. A new experiment to determine the timing of application will be performed during the 2021 season. Each year we expect to include new elite selections in this type of experiment, so that by the time of cultivar release this information will be available to growers.
Dr. PATRICIO MUNOZ, UF Assistant Professor, Blueberry Breeding and Genomics Lab