Modulating the Anthocyanin Pathway to Develop Improved Sweet Oranges
Posted August 2025
Researchers: Manjul Dutt, Nabil Killiny, Jude Grosser
Contact: Manjul Dutt, UF/IFAS CREC manjul@ufl.edu
Summary:
Juice from huanglongbing (HLB)- affected trees often lacks the bright, consistent color and aroma of juice obtained from healthy HLB-free trees. Enhancing the juice quality through the upregulation of anthocyanins offers numerous benefits, both from a nutritional and commercial standpoint. Anthocyanins, which are natural pigments responsible for red, purple, and blue hues in fruits, are potent antioxidants known to support cardiovascular health, reduce inflammation, and protect against certain chronic diseases. Citrus fruits are generally not known for high levels of anthocyanins, apart from the blood oranges. Although blood oranges can grow in the warm subtropical citrus belt, the characteristic blood color from increased anthocyanin production is not achieved due to the lack of cold stress. Genetic manipulation of regular sweet oranges has resulted in citrus trees that produce enhanced anthocyanins even under central and south-central Florida conditions. Enhanced anthocyanins resulting in a deep red color in the young citrus flushes can also deter psyllids by interfering with their visual cues. Proposed field trials will confirm the potential of these genetically modified trees to survive better under endemic HLB conditions while also producing anthocyanin-rich sweet orange fruit.
Take Home Message:
- Enhanced anthocyanin-rich sweet oranges producing fruits in central and south central Florida have been produced.
- Field trials will confirm the ability of these fruits to remain productive under endemic HLB conditions.
