INVESTIGATION OF THE SPREAD OF PEAR RUST (Gymnosporangium sabinae) IN PEAR CULTIVATED IN REGION OF PRISHTINA

Pear rust is a disease caused by the rust fungus Gymnosporangium sabinae, which causes bright orange spots on the upper surfaces of pear leaves in summer and early autumn. In Kosovo, this disease appears every year and poses a serious threat to pear production. The purpose of this study was to investigate the spread of the disease in five pear cultivars (Vilijam, Murgesha, Santa Maria, Krasanka, Abbate Fetel) cultivated in locality of Prishtina. For these investigations, during vegetation period of 2015-2016 in a private orchard with area of 10 ha, split in some blocks with a great care were taken leaves of pear leaves, of all cultivars, with signs of disease caused by the pathogen Gymnosporangium sabinae. The samples for analysis were taken every week from the beginning of May until the end of September, while the results were expressed in every 10 days as a sampling date. To determine the presence of the disease the samples were brought to the laboratory of Plant Protection at Phytosanitary Corporation Sara&Meti in Prishtina and tested on nutrition media (nutrition agar and potato dextrose agar). Based on the results obtained regarding the presence of the disease it was shown that the cultivar Vilijam was more susceptible against pear rust while the cultivar Krasanka was less susceptible and less affected by this disease. After statistical analysis of the research results through analysis of variance (ANOVA), statistical differences were observed at different levels of significances regarding the pear cultivars (Factor A), locality where the pear was cultivated (Factor B), the type of nutrition media (Factor C) and their interactions (AxB), (AxC), (BxC) and (AxBxC).