Mapping and Comparison of Quantitative Trait Loci for Oleic Acid Seed Content in Two Segregating Soybean Populations

Soybean [Glycine max (L.) Merr.] produces 29.4% of the world’s edible vegetable oil. An important determinant of the nutritional value and the oxidative stability of soybean oil is the oleic acid content. Elevation of the oleate content levels leads to the improvement of soybean oil quality. However, our knowledge of the genetic factors underlying oleate variation in soybean seeds remains incomplete, hampering the use of marker-assisted selection in soybean breeding programs. We used a whole-genome scan approach to identify oleate quantitative trait loci (QTLs) in a soybean population segregating for oleic acid content and a cognate segregating population to confi rm oleate QTL. A novel oleate QTL with moderate effects was revealed on linkage group F in the proximity of the simple sequence repeat marker sat_309, which was confi rmed in both populations across all environments tested. Furthermore, this study verifi ed the existence of an oleate QTL with moderate effects in the proximity of FAD2-1B isoform on linkage group I, which interacted epistatically with the oleate QTL on linkage group F. Oleate QTLs with moderate effects were also detected on linkage groups A2 and N only in one of the populations under study. Minor QTLs on linkage groups E, L, A1, and D2 confi rmed previous mapping studies for oleate content in soybean. E. Bachlava, R.E. Dewey, J.W. Burton, and A.J. Cardinal, Dep. of Crop Science, North Carolina State Univ., Raleigh, NC 27695-7620; J.W. Burton, USDA-ARS, Soybean and Nitrogen Fixation Research Unit, Raleigh, NC 27607. Received 11 Oct. 2008. *Corresponding author ([email protected]). Abbreviations: BLUP, best linear unbiased predictor; CIM, composite interval mapping; FAD, fatty acid desaturase; LOD, likelihood of odds; MIM, multiple interval mapping; MQM, multiple-QTL model mapping; QTL, quantitative trait locus; RFLPs, restriction fragment length polymorphisms; SSR, simple sequence repeat. Published in Crop Sci. 49:433–442 (2009). doi: 10.2135/cropsci2008.06.0324 © Crop Science Society of America 677 S. Segoe Rd., Madison, WI 53711 USA All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Permission for printing and for reprinting the material contained herein has been obtained by the publisher.