Prebreeding of Arachis hypogaea: development of materials from reciprocal interspecific crosses between Arachis L. species with genome B and analysis of the meiotic behavior of F1 hybrids

GARCÍA, A.V.; LAVIA, G.I.; VANDECAVEYE, M.A.

Foz do Iguacu, PA

Congreso; 2018 International Congress of Genetics; 2018

Sociedad Brasilera de Genética (SBG) y la Asociación Latinoamericana de Genética (ALAG)

The cultivated peanut Arachis hypogaea (AABB genome) is acrop of world economic importance. Thus, to incorporate features of interest tothe crop, it is essential to develop hybrid materials from wild Arachis species. Arachis ipaënsis and A.williamsii present desirable characteristics to be incorporated into thecultigen. Although these two species are B genome, whether or not they aregenomically homologous has not yet been determined by meiotic behavior. Therebythe aims of this work were to develop hybrid materials from A. ipaënsis and A. williamsii and determine the genomic homology between theparental species. The crosses were made in greenhouse by castrating femaleparent flowers and pollinating them with the male parent. This technique allowedobtaining reciprocal interspecific hybrids. SSR markers and pollen viability wereemployed to verify the hybrid nature of the plants. Meiotic behavior was analyzedby evaluating flower buds. Analysis of pollen mother cells atdiakinesis/metaphase I revealed that 65.7% of cells had 10II. The formation ofmultivalents demonstrated the emergence of reciprocal translocations betweennon-homologous chromosomes. The irregularities observed from Prophase I toTelophase II would result in the formation of aneuploid microspores. Inaddition, the presence of persistent anaphase bridges and tripolar spindleswould be responsible for the formation of unreduced gametes. Successfulhybridization allowed the development of diploid materials with high formationof bivalents and high pollen viability, which indicates that parental specieshave homologous genomes; consequently these are promising materials for geneticimprovement programs of cultivated peanut.