POWDERY MILDEW (Erysiphe graminis f.sp. hordei) IN THE NATURAL POPULATIONS OF WILD BARLEY (Hordeum spontaneum) IN THE A AEGEAN REGION

Abstract

Two hundred Hordeum spontaneum plants were chosen and tagged at early stages of plant development at the Bomova, Meryemana and Emiralem micro-sites in 1996 and 1997. Powdery mildew disease severity and survivals of the selected plants were recorded at three times starting from the 4-5 leaf stage to heading time during the growing period. The results were evaluated comparatively, disease severity of the populations differed, and especially it was rather low at Emiralem. Disease severity increased as the time advanced. Percentage of surviving plants was close to each other at heading stage in three populations, but there were significant differences between two years. Approximately average plant lost was 15% in 1996 and it reached to 36 % in 1997.