Genetic Diversity of Andean Tuber Crop Species in the in situ Microcenter of Huanuco, Peru

Andean tuber crop species oca (Oxalis tuberosa Molina), ulluco (Ullucus tuberosus Caldas), and mashua (Tropaeolum tuberosum Ruiz & Pav.) play major roles in Andean communities. These species show high variability but are threatened with genetic erosion. To study the management of genetic resources of neglected vegetatively propagated crop species, we studied genetic diversity and structure of these species in an in situ diversity microcenter (Huanuco, Peru). A sample of 15 varieties of oca, 15 of ulluco, and 26 of mashua was analyzed with the inter simple sequence repeats (ISSR) molecular markers. Mean genetic distances and global genetic diversities were high for the three species, with higher values for mashua than for oca and ulluco. Assignment technique divided both oca and ulluco samples into two genetic clusters; the mashua sample probably belongs to a single genetic cluster. Inter simple sequence repeats (ISSR) technique showed intravarietal genetic variability for most varieties, suggesting an underestimation of the in situ genetic variability. These results are discussed considering how variation in breeding systems and farmers’ practice infl uenced patterns of genetic diversity. Our fi ndings confi rm the hypothesis of a considerable amount of variability found in neglected Andean tubers and are essential to deserve adequate conservation strategies and to maintain genetic resources of neglected Andean tuber crop species under a threat of genetic erosion. M. Malice and J.P. Baudoin, Univ. of Liege, Gembloux Agro-Bio Tech, Tropical Crop Husbandry and Horticulture, Passage des Déportés 2, 5030 Gembloux, Belgium; J.P. Bizoux, Univ. of Liege, Gembloux Agro-Bio Tech, Biodiversity and Landscape Unit, Passage des Déportés 2, 5030 Gembloux, Belgium; R, Blas, Universidad Nacional Agraria La Molina, Crop Husbandry Department, Ap. 456, Lima 12, Peru. J-P. Bizoux is a postdoctoral researcher of FRS-FNRS. Received 2 Sept. 2009. *Corresponding author ([email protected]). Abbreviations: CI, confi dence interval; FST, degree of genetic differentiation; HT, global species genetic diversity; ISSR, inter simple sequence repeats; PIC, polymorphic information content. Published in Crop Sci. 50:1915–1923 (2010). doi: 10.2135/cropsci2009.09.0476 Published online 1 July 2010. © 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.