Determination of reaction of some culture barley varieties and wild barley genotypes against barley leaf spot disease [Rhynchosporium secalis (Oud.) Davis]

In this study, rections of 35 culture barley varieties and some genotypes of Hordeum spontaneum and Hordeum murinum against Rhynchosporium secalis were determined at the two different experimental fields of Agricultural faculty, Dicle University. Experimental plots were performed as 1 control and 3 repetetion, 1x2 m² dimentions and suitable to block experimental design. Rhynchosporium secalis infected- plant samples of barley were distrubuted to the experimental plots about tillaged period of barley, after dividet to small sections. Development of barley spot disease at plots occured based on natural climatic contition. Determination of the disease at the barley varieties were made about wilting stage of the plants. According to observation, it was determined that the general dimention of disease was heterogen. In connection with this result, disease rate and severity of varieties were measured at two different types. At the first method, measurements were made at the plot sections in which disease severity occured at the most severiry. At the second method, measurenments were made throughout the plots. According to measurements, the 13 of 35 culture barley varieties at the first experimental field and the 11 of 35 culture barley varieties at the second experimental field displayed different degries of the disease. Reaction of sensitive varieties to barley spot pathogen were observed at the second and thirst leaves of plants according to ordering of leaves as up to belov at both areas. According to the first measurement of the first experimental field, Keçiburnu variety was the most resistand and varieties of Barış, Atılır, Samyeli, Fırat, Escadre were susceptible at different degries. According to the second measurement of the first experimental field, varieties of Keçiburcu and Toprak were most resistant and varieties of Escadre and Fırat were sensitive. According to the second measurement of the first experimental area, varieties of Şahin-91, Aydanhanım, Barış, Bolayır, Yesevi-93 were resistant and varieties of Erciyes, Başgül, Samyeli were susceptible. According to the second measurement of the second experimental area, varieties of Şahin-91, Aydanhanım, Yesevi-93, Bolayır were most resistant and varieties of Keçiburcu, Barış, Sladoran, Başgül, Samyeli were susceptible at the different degries As a result, at this study performed under the natural conditions, it was observed that most of the culture barley varieties and genotypes of wild barley species were resisitant to the agent of barley leaf scald. In addition, based on this result, the sowing of the resistant cultivars observed at this study may be suggest for the Diyarbakır region conditions. But, it should be considered that the related resistant varieties can be display the disease symptoms at the different degries during more rainy and humidity years. In addition, it shuld be considered that the new races of the pathogen may reproduce in future times and they may be also infect to the some resistant varieties.