Identification of Phomopsis Species on Some Ornamental and Forest Plants in Iran on the Basis of the Morphological and Molecular Characteristics

Phomopsis is a genus of imperfect plant pathogenic fungus whose hosts comprise several species in different regions of the world, such as grapes, soybean, acacia, hollyhock, velvetleaf, and several other plants. In this study, samples were collected from hollyhock, velvetleaf, purple bauhinia, and acacia plants suspected to be infected with Phomopsis fungi. They were, then, cultured and subjected to the separation and purification steps, and morphological characteristics of the derived isolates were determined. Among the isolates, five representatives (P1 to P5) were selected from Mazandaran province and their DNAs were extracted. The TEF and ITS regions of DNAs were amplified and sequenced. The ITS (4 and 5) region from ribosomal DNA and a part of the TEF gene were amplified and sequenced. The nucleotide sequence of the isolates was compared with the corresponding sequences available in the GeneBank, and the phylogenetic tree of the isolates was constructed. Results showed that the sequence of the isolates P1, P2, and P4 had the highest similarity with Phomopsis malvacearum species. The sequence of the isolate P3 was very similar to Phomopsis loropetali, and the sequence of the isolate P5 was very similar to Phomopsis theicola. The average size of pycnidia produced on three culture media, i.e. CDA, CMA, and PDA, was measured 16 days after incubation at 20-25°C. Sizes were 256 × 85 μm in acacia, 230 × 68 μm in velvetleaf, 230 × 69 μm in hollyhock and 193 × 47 μm in purple bauhinia isolates. Morphological and molecular features of the identified species were matched. The species identified here are reported from Iran for the first time. Symptoms of Phomopsis infection varied with host and identified species.