Alternaria section Panax currently includes seven species which are characterized by simple or branched and short to moderately long primary conidiophores as well as by solitary to short simple or branched chains of conidia with moderate to relatively long secondary conidiophores. Two species within the section have been reported to have sexual morphs. During the study of fungi on overwintered stems of Serratula coriacea Fisch. & C.A.Mey. (Asteraceae) from different regions of Urmia, West Azarbaijan Province, Iran, 26 isolates (16 from conidia and 10 from single ascospores) representing Alternaria characteristics were isolated and studied taxonomically. All the studied isolates formed sexual morph on PDA, PCA, V8–A, and HA media after 2 months incubation in the dark at 4 ºC and fully matured after 3 months. Based on morphological characteristics of sexual and asexual morphs and multiple gene sequences analyses (ITS-rDNA, GAPDH, RPB2 and TEF), the newly studied isolates represented a new species in Alternaria section Panax, which is described and illustrated here as Alternaria hedjaroudei. Alternaria hedjaroudei is phylogenetically close to A. avenicola, A. calycipyricola and A. photistica but it can be distinguished morphologically based on the formation of short chains of conidia (2–3 in a chain), absence of chlamydospores, smaller conidia size, relatively short secondary conidiophores, and fewer transverse septa in mature ascospores. Detailed morphological comparisons with other species in the section Panax are provided.

Apple is the most important fruit tree in West Azarbaijan province of Iran. However, a disease with crown and collar canker and necrosis was observed in three young apple orchards in Urmia, affected 15% and 1% of ‘Red Delicious’ and ‘Golden Delicious’ cultivars, respectively. A fungus with typical characteristics of the asexual morph of Cytospora was regularly isolated from the diseased tissues. Morphological characteristics and phylogenetic analysis inferred from the combined dataset of the ITS–rDNA, parts of LSU, tef1-α, rpb2 and act1 genes revealed that the isolates represent a new species of Cytospora, described herein as Cytospora balanejica sp. nov.. Pathogenicity of all isolates was confirmed on the cv. ‘Red Delicious’ based on Koch’s postulates. Also, the reaction of 12 apple cultivars was assessed against five selected isolates with higher virulence. Results showed that except cv. ‘Braeburn’ which did not produce any symptoms of infection, the other 11 cultivars showed characteristic symptoms including sunken and discolored bark and wood. The mean length of discolored area was different among the 11 so-called susceptible cultivars, hence cvs. ‘M4’ and ‘Golden delicious’ had the highest and the lowest lesion length, respectively. Moreover, the aggressiveness of five tested isolates was varied and the isolates BA 2–4 and BA 3–1 had the highest and lowest aggressiveness, respectively. Based on our observations on the potential ability of the fungus in causing the disease on young and actively growing apple trees, it will be a serious threat to apple cultivation and industry.