Quantitative Trait Loci Associated with Drought Tolerance in Common Bean

Drought stress is the major limitation of common bean (Phaseolus vulgaris L.) grown in subsistence farming systems worldwide. The objective of this study was to use single nucleotide polymorphism (SNP) markers from the BARCBean6K_3 Beadchip to identify quantitative trait loci (QTL) associated with traits related to drought tolerance in common bean. An intergene pool recombinant inbred line (RIL) population from a cross of drought tolerant line SEA5 and CAL96 cultivar was evaluated in Rwanda for 3 yr under drought stress and nonstress and in Colombia for 1 yr under drought stress. Traits evaluated included the numbers of days to flower, maturity, and seed fill; harvest index and pod harvest index; yield and yield components including number of pods per plant, seeds per pod, 100 seed weight (SW), and seed yield per day. Harvest indices, and SW were stable regardless of water treatment while number of pods per plant, seeds per pod, and yield were significantly reduced by drought. A linkage map of the RIL population spanning 1351 cM was constructed using 2122 SNP markers. The map covered all eleven bean chromosomes with an average distance of 0.64 cM between markers. A total of 14 QTL for performance under drought were consistently identified in different environments. Quantitative trait loci associated with phenology and SW traits mapped near previously reported QTL. Linkage between SW and yield QTL SY3.3SC was observed on Pv03 and could be used to simultaneously select for seed yield and size in intergene pool crosses of common bean. G. Mukeshimana, and J.D. Kelly, Dep. of Plant, Soil and Microbial Sciences, Michigan State Univ., 1066 Bogue St., East Lansing, MI 48824; L. Butare, Rwanda Agriculture Board, Kigali, Rwanda; P.B. Cregan, USDA, ARS, Soybean Genomics and Improvement Laboratory, BARC, Beltsville, MD; M.W. Blair, Dep. of Agriculture and Environmental Sciences, Tennessee State Univ., 3500 John A. Merritt Blvd., Nashville, TN 37209. Received 28 June 2013. *Corresponding author ([email protected]). Abbreviations: AFLP, amplified fragment length polymorphisms; CIAT, International Center for Tropical Agriculture; CIM, composite interval mapping; DF, days to flower; DII, drought intensity index; DM, days to maturity; DS, drought stress; HI, harvest index; LOD, logarithm of odds; MAS, marker assisted selection; NP, number of pods per plant; NS, nonstress; NSP, number of seeds per pod; PHI, pod harvest index; QTL, quantitative trait loci; RAPD, random amplified polymorphic DNA; RFLP, restriction fragment length polymorphism; RIL, recombinant inbred line; SNP, single nucleotide polymorphism; SSD, single seed descent; SSR, simple sequence repeat; SY, seed yield; SYD, seed yield per day; SW, 100 seed weight. Published in Crop Sci. 54:923–938 (2014). doi: 10.2135/cropsci2013.06.0427 © 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. Published April 9, 2014