A quantitative real-time PCR assay for the detection of Ramularia collo-cygni from barley (Hordeum vulgare).

ABSTRACT

AIMS: The aim of this study was to develop a real-time quantitative PCR test to recognize and quantify the DNA levels of the increasingly important barley pathogen Ramularia collo-cygni. METHODS AND RESULTS: The method described uses specifically designed primers and a molecular beacon probe based on an internal transcribed spacer (ITS) sequence. Pathogen extracted from barley leaves could be quantified to the picogram level in both leaves showing symptoms of infection and symptomless barley leaves. CONCLUSIONS: A relationship between R. collo-cygni DNA levels and disease symptoms was established in spring barley under natural infection conditions. SIGNIFICANCE AND IMPACT OF THE STUDY To our knowledge, this is the first report of a test of this type and makes an important contribution to studies into the life cycle of this pathogen.