Quantitative Trait Loci and Epistasis for Oat Winter-Hardiness Component Traits

Winter hardiness is a complex trait and poor winter hardiness limits commercial production of winter oat (Avena spp.). The objective of this study was to identify quantitative trait loci (QTL) for fi ve winter-hardiness component traits in a recombinant inbred line population derived from a cross between the winter-tender cultivar Fulghum and the winter-hardy cultivar Norline. Crown freezing tolerance, vernalization response, and photoperiod response were evaluated in controlled environment studies. Heading date and plant height were evaluated over two seasons in Kinston, NC, and winter fi eld survival was evaluated in fi ve environments over two seasons in the mountains of North Carolina and Virginia. A partial genetic linkage map of regions believed to affect winter hardiness was developed using restriction fragment length polymorphism and simple sequence repeat markers. Most QTL were located on linkage groups FN3, FN22, and FN24. Quantitative trait loci were identifi ed for all traits except photoperiod response, and epistatic interactions were identifi ed for winter fi eld survival, crown freezing tolerance, vernalization response, and plant height. Major QTL for winter fi eld survival (R2 = 35%) and crown freezing tolerance (R2 = 53%) were identifi ed on linkage group FN3, which was associated with an intergenomic reciprocal translocation between chromosomes 7C and 17. D.R. Wooten, H.J. Lyerly, and J.P. Murphy, Dep. of Crop Science, Box 7629, North Carolina State Univ., Raleigh, NC 27695-7629; D.P. Livingston III, USDA-ARS and North Carolina State Univ., Dep. of Crop Science, Raleigh, NC 27695-7629; E.N. Jellen, Dep. of Agronomy and Horticulture, Brigham Young Univ., 275 WIDB, Provo, UT 84602; D.S. Marshall and J.B. Holland, USDA-ARS, 1419 Gardiner Hall, North Carolina State Univ., Raleigh, NC 27695. Received 20 Oct. 2008. *Corresponding author ([email protected]). Abbreviations: FN, Fulghum × Norline recombinant inbred line population; FW, Fulghum × Wintok recombinant inbred line population; KO, Kanota × Ogle recombinant inbred line population; LSmean, least-squares mean; MIM, multiple interval mapping; OT, Ogle × TAM O-301; PCR, polymerase chain reaction; QTL, quantitative trait locus or loci; RFLP, restriction fragment length polymorphism; RIL, recombinant inbred line; SSR, simple sequence repeat; T7C-17, intergenomic reciprocal translocation involving chromosomes 7C and 17. Published in Crop Sci. 49:1989–1998 (2009). doi: 10.2135/cropsci2008.10.0612 © 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.