The peculiarities of genetic structure of the Blumeria graminis f. sp. hordei population in Lithuania

In 2010, samples of Blumeria graminis f. sp. hordei both in sporulation and cleistothecia were collected in Lithuania from spring barley variety ‘Dina’. Eighty monopustule isolates were tested on differentials with well-known resistance genes. Frequencies of virulence genes, virulence complexity and pathotypes were detected. Virulence frequencies showed a wide range from 0 to 90%. The clear tendency of virulence increasing for Vla in cleistothecia was observed during the growing season of the pathogen. No virulences were found against resistances, which were present in the line SI1, as well as no matching virulence was found for the resistance gene mlo in Lithuania in 2010. Wide diversity of the population is confirmed by the present of high number of detected pathotypes. In the samples in sporulation, the pathotype a6 a7 a9 a12 k la was the most abundant and the dominant pathotype in cleistothecia was a7 a9 a12 k la. In comparison with 2000, significant changes in virulence genes frequencies, complexity and pathotypes were detected in 2010.