Development of new primers based on gapdh gene for Cercospora species and new host and fungus records for Iran

Abstract

ITS region and protein coding genes such as actA, cmdA, gapdh, his3, rpb2, tef1 and tub2 have been applied to investigate the molecular phylogeny of Cercospora species in recent years. Although gapdh is an informative gene for species delimitation in the genus, difficult amplification of this locuswith available primers limits its use for Cercospora. Therefore, in this study novel primers including GpdF-Cer (5’-TTC ATY GAG CCM CAC TAC GCT-3’) and GpdR-Cer (5’-RTC GGT GAC KRC GAG VAC-3’) were developed to supplement previously published primers for the amplification of gapdh. Besides, in a taxonomic survey on the genus Cercospora in Iran based on consolidated species concept, leaf samples with leaf spot symptoms were collected and Cercospora isolates were characterized based on a combination of morphological features and sequence data from the ITS, actA, cmdA, gapdh, his3 and tef1 loci. Seventeenspeciesof the genus Cercospora were recognized of which C. mercurialis on Mercurialis annua is confirmed for the first time, for Iran (Asia) mycobiota using sequence data of six genomic loci.Several new hosts are recorded for C. apii (one), C. beticola (one), C. cf. flagellaris (10), C. gamsiana (one), C. iranica (one), Cercospora sp. G (three) and Cercospora sp. T (four). Thus, new host families were added to the host range of C. beticola (Brassicaceae), C. cf. flagellaris (Lamiaceae, Polygonaceae, Vitaceae), and Cercospora sp. T (Lamiaceae, Plantaginaceae, Rosaceae) in the world.