Cloning and characterization of anonymous regions of Ascochyta lentis and a. Fabae genomes and suitability of these regions for phylogenetic analysis of Ascochyta species

Abstract

Ascochyta species cause blights on a number of wild and cultivated cool?season legume hosts, including chickpea (Cicer arietinum L.), faba bean (Vicia faba L.), lentil (Lens culinaris Medik.), pea (Pisum sativum L.), and vetches (Vicia spp.). Ascochyta blight of faba bean and lentil are caused by the host?specific fungi A. fabae Speg. and A. lentisVassiljevsky, respectively. Identification of these species has been primarily based on host specificity because they are morphologically indistinguishable (Gossen et al.1986). Previous studies have demonstrated that each species have distinct RAPD?PCR banding patterns (Kaiser et al. 1997), and each form a monophyletic group in a combined phylogeny estimated from glyceraldehyde?3?phospatedehydrogenease (G3PD), translation elongation factor alpha (EF), and chitin synthase (CHS) genes (Peever et al. 2007). No additional fast?evolving markers have been identified for these fungi that would facilitate research at the population/species interface. Therefore, the objective of this research was to develop sequence characterized anonymous region (SCAR) markers for identification of A. fabae and A. lentis, for estimating genetic variation within and among species, and for inferring phylogenetic relationships.