Analysis of WRKY Transcription Factors in Barley Cultivars Infected with Fusarium culmorum

One of the most critical problems of cereal breeding is Fusarium crown rot disease caused by various Fusarium species. Fusarium culmorum is one of the predominant pathogen in Turkey and causes serious product losses. In this study, the early response of barley cultivars upon F. culmorum infection were analyzed by disease severity and gene expression patterns of WRKY transcription factors. In that context, firstly, disease severities of 9 barley cultivars (Hordeum vulgare L. cvs. Epona, Escadre, Gazda, Oliver, Avcı 2002, Burakbey, Tarm 92, Manava, and Ramata) infected with F. culmorum were determined with disease index percentages. After 7 days of infection, Epona was more sensitive than the other cultivars while the lowest disease index was seen in Gazda. Total RNA extractions were performed at 72 hai from the root tissues of Epona and Gazda. Expression analysis of HvWRKY6, HvWRKY9, HvWRKY24, HvWRKY25, HvWRKY33, HvWRKY34, HvWRKY42, and HvWRKY46 genes were conducted by qPCR. As a result of pathogen stress, it was observed that the transcript levels of HvWRKY33 was significantly upregulated in both cultivars. HvWRKY6, HvWRKY34 and HvWRKY46 genes were increased in Epona while upregulation of HvWRKY25 and HvWRKY34 genes were detected in Gazda. No significant decreases were detected in any cultivars. This study is important in terms of providing an association between WRKY genes and pathogen stress response.