Doubled Haploids versus Conventional Breeding in CIMMYT Wheat Breeding Programs

Doubled haploid (DH) technology has been used in breeding programs for several decades and is currently the method of choice in a number of crop species, including barley (Hordeum vulgare L.), rapeseed (Brassica napus L.), maize (Zea mays L.), and wheat (Triticum aestivum L.). In this study we investigated via computer simulation the benefit of using DHs compared with the conventional wheat breeding strategy used at CIMMYT. Two strategies using DHs were considered: DH lines directly derived from F1 hybrids (F1–DH), and DH lines derived from F3 individuals that are retained following selection for agronomic traits in the F2 generation (F3– DH). Genetic gains per cycle, per year, and per dollar spent were consistently higher for conventional breeding than for DH breeding strategies, especially gains per dollar. Though the F1–DH strategy saved 1 yr in completing a breeding cycle, genetic gains per year for the adaptation trait from F1–DH were much lower than those from conventional breeding, where two growing seasons are used per year. Though the DH breeding strategy showed no significant advantages over the conventional wheat shuttlebreeding regime of CIMMYT, we did not exclude the possibility that the DH breeding strategy may have advantages when genetic gains per unit of time are considered, and only one generation is grown per year. The conventional shuttle regime will continue to be the major wheat breeding strategy at CIMMYT, where two cycles can be grown per year and breeders can do selection in large populations in both cycles. H. Li and J. Wang, Institute of Crop Science, CIMMYT China, and The National Key Facility for Crop Gene Resources and Genetic Improvement, Chinese Academy of Agricultural Sciences, Beijing 100081, China; R.P. Singh and H.-J. Braun, International Maize and Wheat Improvement Center (CIMMYT), Apdo. Postal 6-641, 06600 Mexico, D.F., Mexico; W.H. Pfeiffer, HarvestPlus Challenge Programme and International Center for Tropical Agriculture (CIATHarvestPlus), A.A. 6713, Cali, Colombia. Received 20 Feb. 2012. *Corresponding author ([email protected] or [email protected]). Abbreviations: CBs, crossing blocks; DH, doubled haploid; F1– DH, the breeding strategy of DH lines directly derived from the F1 hybrids; F3–DH, the breeding strategy of DH lines derived from F3 individuals that are retained from the selection of agronomic traits in the F2 generation; ID, identification; MODPED, modified pedigree/ bulk selection method; QuLine, a QU-GENE application breeding simulation module; QU-GENE, a simulation platform for quantitative analysis of genetic models developed by the University of Queensland (http://www.uq.edu.au/lcafs/qugene/), Australia; SELBLK, selected bulk selection method. Published in Crop Sci. 52:74–83 (2012). doi: 10.2135/cropsci2012.02.0116 © Crop Science Society of America | 5585 Guilford 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.