Phylogenetic analysis of North American plums (Prunus sect. Prunocerasus: Rosaceae) based on nuclear LEAFY and s6pdh sequences

Phylogenetic analysis of DN A sequences from two low-copy nuclear genes (LEAFY and s6pdh) was conducted to investigate relationships among native plums of North America (Primus sect Prunocerasus) The cladograms resulting from maximum parsimony and Bayesian inference are poorly resolved and mcongruent with clades based on chloroplast DNA sequences. Evidence from both nuclear genes confirms the placement of P. texana in sect. Prunocerasus. Sequences of P americana and P. mexicana form a monophyletic group on the s6pdh cladogram, but most P amencana collections also have a second divergent sequence, which together form a clade sister to P. subcordata The shared possession of a 250-bp insertion within LEAFY intron 2 supports a close relationship between P. hortulana and P. murrayana Primus alleghaniensis, P. gracilis, P. mantima, and P umbdlata form a paraphyletic group on the LEAFY cladogram, basal to a clade composed of P. angustifolia and angustifolia-hke sequences of P nvulans and P. munsoniana Data from LEAFY and s6pdh suggest hybrid origins for P. nvularts and P. munsoniana, with P angustijoha as one progenitor.