Email updates

Keep up to date with the latest news and content from BMC Plant Biology and BioMed Central.

Open Access Research article

BAC libraries construction from the ancestral diploid genomes of the allotetraploid cultivated peanut

Patricia M Guimarães1*, Olivier Garsmeur2, Karina Proite13, Soraya CM Leal-Bertioli1, Guilhermo Seijo4, Christian Chaine2, David J Bertioli5 and Angelique D'Hont2

Author Affiliations

1 Biotechnology Unit, Embrapa Genetic Resources and Biotechnology, Brasília, DF, Brazil

2 Centre de Coopération International en Recherche Agronomique pour le Developpement (CIRAD), Montpellier, France

3 Cell Biology Department, IB-University of Brasília (UnB), Brasília, DF, Brazil

4 Plant Cytogenetics and Evolution Laboratory, Instituto de Botánica del Nordeste, Corrientes, Argentina

5 Biotechnology and Genomic Sciences Department, Campus II Catholic University of Brasília, Brasília, DF, Brazil

For all author emails, please log on.

BMC Plant Biology 2008, 8:14  doi:10.1186/1471-2229-8-14

Published: 29 January 2008

Abstract

Background

Cultivated peanut, Arachis hypogaea is an allotetraploid of recent origin, with an AABB genome. In common with many other polyploids, it seems that a severe genetic bottle-neck was imposed at the species origin, via hybridisation of two wild species and spontaneous chromosome duplication. Therefore, the study of the genome of peanut is hampered both by the crop's low genetic diversity and its polyploidy. In contrast to cultivated peanut, most wild Arachis species are diploid with high genetic diversity. The study of diploid Arachis genomes is therefore attractive, both to simplify the construction of genetic and physical maps, and for the isolation and characterization of wild alleles. The most probable wild ancestors of cultivated peanut are A. duranensis and A. ipaënsis with genome types AA and BB respectively.

Results

We constructed and characterized two large-insert libraries in Bacterial Artificial Chromosome (BAC) vector, one for each of the diploid ancestral species. The libraries (AA and BB) are respectively c. 7.4 and c. 5.3 genome equivalents with low organelle contamination and average insert sizes of 110 and 100 kb. Both libraries were used for the isolation of clones containing genetically mapped legume anchor markers (single copy genes), and resistance gene analogues.

Conclusion

These diploid BAC libraries are important tools for the isolation of wild alleles conferring resistances to biotic stresses, comparisons of orthologous regions of the AA and BB genomes with each other and with other legume species, and will facilitate the construction of a physical map.