The genus Juglanconis (Diaporthales) on Pterocarya

Abstract

Based on molecular phylogenetic analyses of a multigene matrix of partial nuSSU-ITS-LSU rDNA, cal, his, ms204, rpb1, rpb2, tef1 and tub2 sequences, recent European and Iranian collections of Melanconium pterocaryae from the type host, Pterocarya fraxinifolia, are shown to be distinct from the Japanese Melanconis pterocaryae from Pterocarya rhoifolia, and both are confirmed as closely related members of the recently described genus Juglanconis. Therefore, the new name Juglanconis japonica is proposed for Melanconis pterocaryae. As no type collection could be traced, Melanconium pterocaryae (syn. J. pterocaryae) is neotypified, described and illustrated, and it is recorded for Europe for the first time. During field surveys in natural stands of P. fraxinifolia in Guilan province (Iran), Juglanconis pterocaryae was consistently isolated from tissues affected by branch and trunk cankers, twig dieback and wood necrosis, indicating that it is the causal agent of these diseases. The external and internal symptoms associated with these trunk diseases are described and illustrated.

The genus Melanconis (Diaporthales)

“…Here we also validate the neotypification of Melanconium pterocaryae, the basionym of Juglanconis pterocaryae by Voglmayr et al (2019), where the new requirement to explicitly state the MBT number in the typification proposal was missing:…”

“…0.45 kb fragment was amplified with primers T1 (O'Donnell and Cigelnik 1997) and BtHV2r (Voglmayr et al 2016) or a ca. 1.6 kb fragment with primer pairs T1 and T22 (O'Donnell and Cigelnik 1997) or T1D and T22D (Voglmayr et al 2019). Table 1.…”

“…The newly generated sequences were aligned with the Melanconis sequences of Fan et al (2016Fan et al ( , 2018 and a few additional GenBank sequences. Species of Juglanconis were selected as outgroup (Voglmayr et al , 2019; the GenBank accession numbers of the sequences, used in the phylogenetic analyses, are given in Table 1. All alignments were produced with the server version of MAFFT (www.ebi.ac.uk/Tools/mafft), checked and refined using BioEdit v. 7.2.6 (Hall 1999).…”

“…Although light coloured discs are not uncommon in Melanconiella, Wehmeyer's (1941) section Chrysostromae of his subgenus Eumelanconis basically matches the phylogenetically conceived genus Melanconiella, except for a few species, which belong elsewhere. For some of these species, the new genus Juglanconis was established in the new family Juglanconidaceae (Voglmayr et al , 2019. Two other species were segregated from Melanconis to Alnecium and Phaeodiaporthe by Voglmayr and Jaklitsch (2014).…”

Linosporopsis, a new leaf-inhabiting scolecosporous genus in Xylariaceae

“…1.2kb fragment of the RNA polymerase II subunit 2 (RPB2) gene with primers dRPB2-5f and dRPB2-7r (Voglmayr et al 2016a); and a ca. 1.6-kb fragment of the beta-tubulin (TUB2) gene with primers T1D and T22D (Voglmayr et al 2019). PCR products were purified using an enzymatic PCR cleanup (Werle et al 1994) as described in Voglmayr and Jaklitsch (2008).…”