2018 ASHS Annual Conference

Poinsettia (Euphorbia pulcherrima) is the most popular holiday potted plant, with eye-catching bracts colored by anthocyanin pigments that attract consumers to buy the plants every holiday season. Poinsettia breeders are constantly challenged to create new and improved cultivars for the industry, and anthocyanin profiles can aid in cultivar development. Identification and measurement of anthocyanins in poinsettia cultivars has not been conducted since the 1980’s, thus pigment profiles of modern poinsettia cultivars are lacking. A standard method to identify and quantify the anthocyanins in poinsettia bracts using High Performance Liquid Chromatography (HPLC) does not exist. Methods for extracting and analyzing anthocyanins in pitanga fruit were adapted for poinsettia bracts. Methanol extraction was followed by pre-purifications to remove lipophilic compounds and separation from other flavonoids using a C18 solid matrix. Finally, acid hydrolysis removed sugars from the compound before analysis using HPLC. The adapted protocol results in accurate identification and quantification of the anthocyanins in poinsettia bracts and also in optimal HPLC chromatograms of high resolution with sharp symmetrical shape on a flat baseline. An updated, efficient HPLC protocol to identify and quantify the anthocyanins in poinsettias will be used to characterize the anthocyanin profiles of modern cultivars and create a database of the pigments. It will also be used in future studies to quantify the effects of temperature and light on anthocyanin content in poinsettia bracts. Ultimately this information will be beneficial to poinsettia breeders when characterizing new germplasm and new hybrids. We thank the Monsanto Graduate Fellowship for funding.