QTL Analysis of Seed Iron, Zinc, and Phosphorus Levels in an Andean Bean Population

Iron and zinc are essential micronutrients for human health often found in insuffi cient quantities in the diet. Biofortifi cation of seed crops has been undertaken to reduce micronutrient malnutrition. The objectives of this study were to identify variability for seed Fe, Zn, P, and phytic acid levels in an F5:7 recombinant inbred line (RIL) population developed from a cross between AND696 and G19833, both common beans (Phaseolus vulgaris L.) of Andean origin. Quantitative trait loci (QTL) analysis was conducted with data from 2 yr and 2 P treatments with a previously described linkage map of AND696/ G19833. Signifi cant environmental and genetic variability for Fe, Zn, and P levels was identifi ed, and Fe and Zn levels were correlated (up to r = 0.53). Quantitative trait loci for seed Fe and Zn co-localized on three linkage groups (B1, B6, and B11). On B6, a QTL for Fe (R2 = 0.36) was found at the same marker interval as a QTL for seed Zn (R2 = 0.39), both derived from AND696. Quantitative trait loci for seed P were identifi ed on six linkage groups and explained 17 to 55% of the total phenotypic variation depending on year and environment. K.A. Cichy, Dep. of Horticulture, Michigan State Univ., East Lansing, MI 48824. Current address: USDA-ARS, 494 Plant and Soil Science Bldg., East Lansing, MI 48824; G.V. Caldas and M.W. Blair, Biotechnology Unit, International Center for Tropical Agriculture, Cali, Colombia; S.S. Snapp, Dep. of Crop and Soil Sciences and Kellogg Biological Station, Michigan State Univ., East Lansing, MI 48824. Received 20 Oct. 2008. *Corresponding authors ([email protected], [email protected]). Abbreviations: CIM, composite interval mapping; HP, high P; HPLC, high-performance liquid chromatography; LP, low P; MIM, multiple interval mapping; PA, phytic acid; QTL, quantitative trait loci; RIL, recombinant inbred lines. Published in Crop Sci. 49:1742–1750 (2009). doi: 10.2135/cropsci2008.10.0605 © 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.