Comparative fatty acid content of seeds of four Cucurbita species grown in a common (shared) garden

Great variation has been observed in fatty acid content of pumpkin seeds from Cucurbita pepo, while other pumpkin or winter squash species, including C. moschata, C. maxima, and C. argyrosperma (aka C. mixta), have been inadequately studied. Varieties of these four species were grown in a common (shared) garden. Total extractable lipids in seeds were measured; quantity of fatty acids in a lipophilic extract and content of palmitic, stearic, oleic and linoleic acids were determined by GC-FID, as was the quantity of free fatty acids. Considerable variation in total lipid content and composition, within as well as among species, was observed; on average, C. pepo had the lowest proportion of saturated fatty acids, whereas C. maxima had the highest. Hybridization in open-pollinated fruits affected seed fatty acid phenotype, and open-pollinated fruits had higher total lipid content.