Integrating Phenotypic Evaluations with a Molecular Diversity Assessment of a Brazilian Collection of Common Bean Landraces

Common bean (Phaseolus vulgaris L.) is the most important legume crop for direct human consumption in Brazil. Overall patterns of genetic diversity of common bean in the country are not well understood. Hence, this study sought to integrate morphological and agronomic evaluations with prior molecular diversity data from a geo-referenced collection of Brazilian common bean. Our sample included 279 randomly chosen landrace accessions from the main growing regions of beans in Brazil. Eighteen morphological and three agronomic characters (yield and susceptibility to common bacterial blight and rust diseases) were evaluated in fi eld conditions in Brazil or California. Results show that the sample was diverse morphologically but did not include all the morphological variability described in domesticated common bean outside Brazil. Several accessions showed clear morphological differences in spite of having the same name. The integration of the current morphological and agronomic evaluations with a prior 74-marker diversity assessment of the same landraces improved the identifi cation of fi ve subpopulations identifi ed on the basis of microsatellite diversity. These subpopulations could be distinguished by their morphology, the type and frequency of the market classes they included, and the frequency of susceptibility to diseases. This information will facilitate the management and use of P. vulgaris genetic diversity in Brazil. M.L. Burle, S.R. Temple, and P. Gepts, Dep. of Plant Sciences/MS1, Section of Crop and Ecosystem Sciences, Univ. of California, Davis, CA 95616-8780; M.L. Burle, current address: EMBRAPA Recursos Genéticos e Biotecnologia, Pq. EB Av. W5 Norte (Final), Caixa Postal 02372, Brasília, DF 70770-900, Brazil; J.R. Fonseca, M.J. del Peloso, and L.C. Melo, EMBRAPA Arroz e Feijão, Rodovia GO-462, Km 12, C.P. 179, Santo Antônio de Goiás, GO, Brazil. Received 16 Dec. 2010. *Corresponding author ([email protected]). Abbreviations: PrinComp1, PrinComp 2, and PrinComp 3, fi rst, second, and third principal components, respectively; QTL, quantitative trait locus; SCAR, sequence-characterized amplifi ed region; SSR, simple sequence repeat. Published in Crop Sci. 51:2668–2680 (2011). doi: 10.2135/cropsci2010.12.0710 Published online 16 Sept. 2011. © 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.