Genetic diversity among Spanish pea (Pisum sativum L.) landraces, pea cultivars and the World Pisum sp core collection assessed by retrotransposon-based insertion polymorphisms (RBIPs)

A total of 122 accessions of different wild and cultivated Pisum sp. were analysed using retrotransposon-based insertion polymorphisms (RBIP) markers. The Pisum materials included wild and cultivated (landraces and cultivars) materials from the World core collection of the John Innes Centre (JI) representing all generally recognized Pisum taxa, landraces materials from the Spanish core collection, and commercial pea cultivars largely sown in Spain. The overall polymorphism detected by RBIP marker was high and all accessions, except two pairs, could be distinguished by their marker pattern. Principal component and phylogenetic analyses clearly discriminated P. fulvum and P. abyssinicum samples from both each other and P. sativum, while P. elatius and P humile samples were scattered among the other taxa clusters, supporting the existence of three well defined taxa in the genus Pisum (P abyssinicum, P. fulvum and P. sativum). These results also suggest that the Spanish pea core collection of landraces maintains a relatively high variability which is only partially represented in cultivars generally sown in Spain. Thus, Spanish landraces are still a source of genetic variability for breeding new pea cultivars.