VIRULENCE GENES ANALYSIS AND FUNGICIDE-SE NSITIVITY OF BARLEY POWDERYMILDEW POPULATION (ERYSIPHE-GRAMINIS F-SP HORDEI) IN HUNGARY IN 1993

In 1993 the frequency of virulence genes and fungicide - sensitivity i n regional populations of barley powdery mildew was found in Hungary. Samples of pathogen spores were trapped by jet spore sampler mounted o n a car roof. In all observed regions we found high virulence frequenc ies against resistance genes M1-g, M1-k, M1-a6, M1-a12 and M1-La. We f ound the lowest virulence frequency against fesistance genes M1-a7, +A B and M1(W) with considerable regional differences. No isolate of path ogen virulene against recessive resistance gene m1-o throughout Hungar y was found. Population of powdery mildew from Hungary has a decreased sensitivity against fungicides of the triazole group. The lowest sens itiviti against triadimenol (Bayfidan) and flutriafol (Impact) was fou nd. The most resistant pathogen population from western Hungary was fo und against propiconazole (Tilt). At triazole fungicides the highest s ensitivity of pathogen population against tebuconazol (Folicur) was ob served. Population of pathogen is sensitive against morpholine compoun d - fenpropimorph (Corbel) on the level of standard control isolates.