Isolation and Identification of Endophytic and Grape Trunk Diseases Associated Fungi in Zanjan Province

Endophytic and grapevine trunk diseases associated fungi were isolated from Zanjan province and their inhibitory effect on 2 grapevine fungal pathogens Cytospora chrysosperma and Fusarium sp. was investigated. A total of 95 fungal isolates were isolated, of which 63/54% were from healthy and 36.45% were from diseased tissues. Using strong disinfection steps, probability of isolation of saprophytic fungi was decreased to minimum; So, the fungi isolated from healthy and infected tissues considered as endophytes and grapevine trunk diseases associated fungi, respectively. Preliminary molecular identification of 13 representative isolates in terms of morphological characteristics was performed using nucleotide sequencing of ITS–rDNA region was done and 10 genera were identified. The taxa of Alternaria malorum, Alternaria sp., Allocanariomyces tritici, Aaosphaeria arxii, Clonostachys rosea, Chaetomium sp., Daldinia loculata, Daldinia sp., Fusarium oxysporum, Fusarium sp., Macrophomina phaseolina, Phaeoacremonium minimum and Stromatinia narciss were identified. Pathogenicity of A. tritici, C. rosea and F. oxysporum was confirmed. Antagonistic activity of 13 fungal isolates against pathogenic fungi of grapevine trunk diseases (GTDs) including C. chrysosperma and Fusarium sp. using dual–culture method showed that species of F. oxysporum, P. minimum and C. rosea had the greatest potential as biocontrol agents. In this study, two species of A. arxii and S. narcissi were isolated from healthy grape tissue and to the best of our knowledge; are reported for the first time as endophytic fungi of grapevine trees in the world. D. loculata was isolated from infected tissues of grape trunk and is reported for the first time as a fungi associated with grapevine trunk diseases from the world. Moreover, the pathogenicity of A. tritici and F. oxysporum, was proved in green house condition and are reported for the first time as grapevine pathogens from the world.