Collaborative research between our groups at UMD and the UMass Amherst Cranberry Experiment Station is designed to investigate the effects of growing practices on fruit quality, with particular emphasis on determining the relationship between the production of healthful phenolic compounds in the fruit and the availability of light and/or non-structural carbohydrates in the vine. Two sets of field studies were conducted in 2004. The effects of partial defoliation of new growth on ‘Stevens' cranberry vines was assessed. In a separate study, the use of reflective mulch to increase light exposure to grape clusters was investigated using 'Merlot' and ‘Pinot noir' wine grapes. Fruit was harvested in October and the content of phenolics, anthocyanins, flavonols, soluble sugar, starch and total carbohydrates was determined by HPLC and spectrophotometric methods. In cranberry plants, treatment did not significantly affect total phenolics. A significant negative correlation was observed between soluble sugar in the plant and total anthocyanin content in the fruit, indicating that production of anthocyanins in cranberry fruit may partially be a stress-related response. In grapevines, the treatment did not significantly affect content of phenolics or flavonoids. The results of these studies and implications for future study will be presented.
Back to Nutritional Chemistry Poster Session
Back to The 33rd Northeast Regional Meeting (July 14-17, 2005)