Effect of planting date on sunflower seed oil content, fatty acid composition and yield in Florida

Plantings of sunflower,Heliantbus annuus L., were made 5 times between Feb. 2 and Nov. 15 in Florida so that the effect of planting date on the fatty acid composition of sunflower oil might be assessed. Eleven popular hybrids were planted at Gainesville, FL, on Feb. 2 and 28, April 2, and Aug. 14, and 15 hybrids were planted at Lake Worth, FL, on Nov. 15. Sunflower planted on Nov. 15 would be subjected to freezing temperatures if grown in Gainesville. Yields of sunflower achenes for the four planting dates at Gainesville declined with lateness of planting date. Oleic acid content of the oil (17.6–58.4%) was intermediate for the February plantings, highest for the April planting, and lowest for the late plantings. The linoleic acid content (32.5–71.0%) varied inversely with the oleic acid content. Because sunflower oil is needed for different purposes, such as for salad oil, for deep frying and for making margarines, oil low in linoleic acid (high in oleic acid) as well as oil high in linoleic acid (low in oleic acid) are needed. In Florida, adjusting the planting dates should result in the production of oil of the desired fatty acid composition.