2017 ASHS Annual Conference

Phytochemicals are plant metabolites that do not have a defined recommended daily intake (RDI), but have strong radical scavenging activities and are associated with reducing the risk of some chronic diseases. Of the different phytochemicals, polyphenols are difficult to measure and not commonly selected for in plant breeding programs. Genome-wide association studies (GWAS) can be used to determine the genetic locations of difficult to measure traits and allow for the development of molecular makers to easily track traits in breeding populations. Fruit were harvested from 140 mandarin accessions at the University of California Riverside Citrus Variety Collection. Fruit samples were ground with liquid nitrogen and freeze dried. Polyphenols were extracted from the dried samples, and measured with LC-MS/MS. Polyphenol data was then paired with genomic data. GWAS and marker development of polyphenols will enable citrus breeders identify genetic locations of difficult to measure traits and to create new cultivars with human health benefits. Tracking traits with molecular markers will ensure that beneficial traits are not lost in progeny. Development of new cultivars with beneficial polyphenols and marketing them as such may accelerate consumer demand and variety adoption.