ARS | Publication request: CORRELATED RESPONSE OF FATTY ACID COMPOSITION TO NINE CYCLES OF RECURRENT SELECTION FOR INCREASED OIL CONTENT IN OAT

Submitted to: Euphytica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 30, 2000
Publication Date: N/A

Interpretive Summary: In a previous study, we reported that nine cycles of selection for higher oil content in oat resulted in dramatic increases in oil content. Lines with oil content of up to 18% were developed; these are by far the highest levels of oil content ever reported in oat. Higher oil oat could be useful as a higher energy animal feed or even as an oil seed crop for human food oil. In either case, but particularly, for human food, it is important to know what the quality, as well as the quantity, of oil is in these higher oil oat lines. The quality of oil largely depends on the proportion of fatty acids, with a higher proportion of unsaturated fatty acids being preferable. We determined the fatty acid contents of oat oil from lines selected from each of the nine cycles of selection and from the original unselected population. The ratio of unsaturated to saturated fatty acids increased with each cycle of selection. Thus, the selection program resulted in improving both the quantity and the quality of oat oil.

Technical Abstract: Groat oil of oat (Avena sativa L) has good quality for human nutrition, but it has not been economically feasible to extract oat oil on a large scale because the oil content of typical oat cultivars is below 10%. We have developed an oat population with elevated groat oil content from nine cycles of recurrent selection for increased oil content. This population may provide valuable germplasm for developing oat cultivars with high oil content to be used for oat oil production. We evaluated 20 random lines from the base population and from each of nine selection cycles to evaluate the effect of selection for higher oil content on fatty acid composition. Oleate and stearate contents increased over cycles of selection, as did the ratio of mono- and polyunsaturated fatty acids to saturated fatty acids. Palmitate, linoleate, and linolenate contents decreased over cycles of selection. Continued changes in contents of all fatty acids may be expected with continued selection for higher oil content, except that linolenate content may not decrease below its current level of 0.8%. Oil quality has improved as a consequence of recurrent selection for higher oil content in this population.