eng Oriental Scientific Publishing Company Biosciences Biotechnology Research Asia 0973-1245 2024-09-30 21 3 1037 1042 10.13005/bbra/3283 52886 article Sabina Jafarzadeh 1 Elman Iskender 1 Institute of Microbiology, Ministry of Science and Education of Azerbaijan Republic , Azerbaijan Our findings highlight the significant biotic factors affecting Pyrus L. and provide insight into the health challenges faced by these species in their natural habitat. This research underscores the importance of monitoring fungal pathogens to develop effective management strategies for the conservation of Pyrus L. biodiversity in the region.  The stationary stations were the North-Eastern regions of the Greater Caucasus (Guba, Khizi in Azerbaijan area) along with the Central Botanical Garden with in ex situ conditions. Various microscopic pathogenic fungi have been investigated in this research. Morphological (colony morphology, spore form) and different determinants were used to determine their characteristics. It was found that the various pathogens were observed in Pyrus L.  in species of the genus Pyrus  microscopic fungi they cause disease such as Phyllosticta pinna Sacc.,  Fusicladium pirinum Fuck.,  Botrytis cinerea Pers. Different infection sources are thoroughly described in relation to both harvesting and post-harvesting handling and intervention practices. The diseases are influenced by various environmental factors, with specific temperature ranges outlined for disease development and causal agents identified. Previous studies have focused on diagnostic indicators, such as optimal environmental conditions for fungal growth in Pyrus L., including temperature, pressure, pH, water activity, and oxygen levels, summarized under both in situ and ex situ conditions. The research included five species of the genus Pyrus L.: Pyrus caucasica Fed., Pyrus communis L., Pyrus georgica Kuth., Pyrus vsevolodi Heideman, and Pyrus salicifolia Pall. https://www.biotech-asia.org/vol21no3/determination-of-fungal-pathogens-in-the-species-of-genus-of-pyrus-l-as-biotic-factor-in-greater-caucasus-azerbaijan/ Fungi;  Microorganism; Pyrus .L.; Pathogen; Spoilage