گونه‏ های جدید ازColletotrichum از روی گیاهان وحشی تیره گرامینه و اویارسلام در برخی از استان‏ های شمالی ایران

In order to isolate and identify Colletotrichum species from a variety of wild Poaceae and Cyperacea plants in some areas in the northern provinces of the country, sampling were conducted from the mentioned plants showing anthracnose and leaf spot symptoms in their tissues. The sampling was done during the spring, summer and autumn seasons of 2018-2019 in different regions of Golestan, Mazandaran, Guilan and East Azarbaijan provinces. A total of 72 pure fungal isolates of Colletotrichum were obtained, including 19 isolates with straight conidia and 53 isolates with falcate/curved conidia. Fungal isolates showed great diversity in terms of morphological criteria and colony characteristics. Grouping of isolates was based on morphological criteria and comparison of DNA fingerprinting pattern using BOX molecular marker. Identification of isolates was performed based on a combination of morphology and nucleotide sequences of several genomic regions including Sod2, Apn2, MAT1/APN2, TUB2 and ITS-rDNA. Three known species, including C. nicholsoni from dallisgrass (Paspalum diliatum), C. sublineola from Johnson grass (Sorghum halepense) and wild sugarcane (Saccharum spontaneum), C. cereale from ryegrass (Lolium sp.) and wild sugarcane (Saccharum spontaneum), and three unknown species, include Colletotrichum sp. 1 from umbrella papyrus (Cyperus alternifolius), Colletotrichum sp. 2 from barnyard grass (Echinochloa sp.), Colletotrichum sp. 3 from the unknown host (Poaceae sp.) were identified. To our knowledge, this study is the first report of isolation of Colletotrichum from barnyard grass and marsh palm plants in Iran. Colletotrichum sp. 1, Colletotrichum sp. 2 and Colletotrichum sp. 3 are considered as new species candidates to the world's mycobiota. Comprehensive morphological studies and multigene phylogenetic analysis are underway to describe the species.