Confi rmation of Molecular Markers and Agronomic Traits Associated with Seed Phytate Content in Two Soybean RIL Populations

The concentration of phytate is an important consideration when analyzing feed grain for livestock. Simple sequence repeat markers Satt237 and Satt561 were found to be linked to quantitative trait loci (QTLs) for phytate concentration in soybean [Glycine max (L.) Merr.] seed. Previous research also established a signifi cant correlation between seed inorganic phosphorus (Pi) and seed phytate. The objectives of this study were to confi rm these QTL in independent environments and populations, to compare the effectiveness of marker-assisted selection with that of phenotypic selection for low phytate, and to evaluate agronomic traits associated with low phytate soybean. The low phytate soybean mutant CX1834-1-2 was crossed with the cultivar 5601T and line S971688 to form two populations. The Satt237 marker was linked to a major QTL (R2 > 0.10) governing seed phytate, and Satt561 was linked to a minor QTL (R2 < 0.10) in both populations. These two confi rmed QTL have been named cqPha-001 and cqPha-002. The phenotypic correlations were signifi cant (P < 0.05) for plant height (r = 0.26), seed protein (r = −0.19), and seed oil (r = 0.17). Phenotypic selection was found to be more effective in lowering mean phytate levels and more cost effi cient. A.M. Scaboo, Dep. of Crop, Soil, and Environmental Sciences, Univ. of Arkansas, 115 Plant Science Bldg., Fayetteville, AR 72701; V.R. Pantalone, D.R. West, and C.E. Sams, Dep. of Plant Sciences, Univ. of Tennessee, 2431 Joe Johnson Dr., 252 Ellington Plant Science Bldg., Knoxville, TN 37996; F.R. Walker, Dep. of Biosystems Engineering and Soil Science, Univ. of Tennessee, 2506 E J Chapman Dr., Knoxville, TN 37996; D.R. Walker, USDA-ARS Soybean/Maize Germplasm, Pathology, and Genetics Research Unit, Urbana, IL 61801; H.R. Boerma, Dep. of Crop and Soil Sciences, Univ. of Georgia, Center for Applied Genetic Technologies, 111 Riverbend Rd., Athens, GA 30602. Received 8 Nov. 2007. *Corresponding author ([email protected]). Abbreviations: ETREC, East Tennessee Research and Education Center; LG, linkage group; MAS, marker-assisted selection; MG, maturity group; PCR, polymerase chain reaction; Pi, inorganic phosphorus; QTL, quantitative trait locus; RIL, recombinant inbred lines; SSR, simple sequence repeat. Published in Crop Sci. 49:426–432 (2009). doi: 10.2135/cropsci2007.11.0614 © 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.