Crossability between Arachis gregoryi (Fabaceae) and wild Arachis species with distinct genomes

Abstract

Cross-compatibility studies in Arachis L. have brought to light possible new sources of genes for introgression in cultivated peanuts. A total of 32 different crosses were made, using accession V14957 of A. gregoryi C.E. Simpson, Krapov. & Valls as the female parent and Arachis species containing seven distinct genomes as male parents. The 3167 pollinations resulted in 153 confirmed inter and intraspecific hybrids. Viability estimates of paternal pollen by staining (PVS) varied from 46.75 to 99.17%, while the pollen count of the hybrids varied from 0.3 to 43.6%, this highest PVS resulting from an intraspecific combination, which suggests appreciable variability in accessions of A. gregoryi. Viability estimates of paternal pollen by germination (PVG) resulted in consistently lower values for all materials, ranging from 41.91% to 88.00%. Arachis gregoryi is important to expand the available diversity of species associated with the peanut B genome; it has a potential to be incorporated as a parent in crosses that aim to expand the genetic base of peanuts and may be useful for concentrating important genes in pre-breeding lines associated with the B genome.