©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 14 (4): 17574-17586 (2015) Crossability of Arachis valida and B genome Arachis species D.C. Wondracek-Lüdke 1,2 , A.R. Custodio 2 , C.E. Simpson 3 and J.F.M. Valls 4 1 Programa de Pós-Graduação em Botânica, Universidade de Brasília, Brasília, DF, Brasil 2 CNPq/Embrapa Recursos Genéticos e Biotecnologia, Brasília, DF, Brasil 3 Texas A&M AgriLife Research, Stephenville, TX, USA 4 Embrapa Recursos Genéticos e Biotecnologia, Brasília, DF, Brasil Corresponding author: D.C.Wondracek-Lüdke E-mail: daniele.wondracek@gmail.com Genet. Mol. Res. 14 (4): 17574-17586 (2015) Received May 6, 2015 Accepted September 11, 2015 Published December 21, 2015 DOI http://dx.doi.org/10.4238/2015.December.21.30 ABSTRACT. The peanut (Arachis hypogaea) is an important food crop in much of the tropical and semi-tropical parts of the world. The peanut is an allotetraploid with an AABB genome formula derived from diploids A. duranensis (A genome) and A. ipaënsis (B genome). The success of an introgression program that aims to improve cultivated varieties of the peanut depends on whether the chosen B genome species is homologous with the B genome of the peanut. While not directly involved in the origin of the peanut to the best of our knowledge, Arachis valida is a B genome species that could potentially be a bridge species or a source of new and different alleles, because of its resistance to diseases and pests. In this study, we investigated the crossability of A. valida with five other B genome species of section Arachis. Eight cross-combinations were made with A. valida and A. gregoryi, A. ipaënsis, A. magna, A. valida, and A. williamsii. Two hundred and forty pollinations were made yielding 61 fruit segments, 61 seeds, one abortion, and 24 hybrid plants. An analysis of the morphological characteristics and pollen viability confirmed that the plants