SHAW, JOEY* and RANDALL SMALL. Department of Botany, University of Tennessee, Knoxville, TN 37996. - A preliminary phylogeny of Prunus section Prunocerasus (Rosaceae).
Prunus subgen. Prunophora sect. Prunocerasus (the
North American plums) mainly occurs in eastern North America and has
long been taxonomically controversial because it lacks consistent
morphological characters. Further complicating the taxonomy are
blurred species boundaries possibly due to recent divergence or
hybridization. Rehder (1940), the most widely adopted classification
of Prunus, recognizes 13 species in sect. Prunocerasus.
Phylogenetic analysis using ITS sequences of nuclear ribosomal DNA
(nrDNA) and the chloroplast trnL-trnF spacer was conducted to
construct the evolutionary history and to evaluate the historical
classification and species boundaries of sect. Prunocerasus.
Preliminary results show that these sequences lack the phylogenetic
information necessary to resolve the aforementioned questions and
other sequences including the GBSS gene are currently under
investigation.
Key words: Prunocerasus, phylogeny, Prunus