Pleiocarpon gen. nov. and a new species of Ilyonectria causing basal rot of Strelitzia reginae in Italy

Abstract

During 2015, a new basal rot disease was observed on potted plants of Strelitzia reginae in an ornamental nursery located in eastern Sicily. Isolations from symptomatic parts of these diseased plants consistently yielded cylindrocarpon-like isolates. Multigene analyses of the partial gene regions of 28S large subunit nrDNA, β-tubulin, histone H3, translation elongation factor 1-alpha, internal transcribed spacer region and intervening 5.8S nrRNA gene, and RNA polymerase II second largest subunit genes, supported by morphological characters supported the recognition of a new genus, Pleiocarpon based on P. strelitziae sp. nov., and a new Ilyonectria species, described here as I. strelitziae sp. nov. The pathogenicity of both I. strelitziae and P. strelitziae were confirmed on young plants cultivated under controlled conditions in a growth chamber. Both cylindrocarpon-like fungi were pathogenic to S. reginae and reproduced symptoms similar to those observed in the nursery. Of the two species, P. strelitziae was more aggressive than I. strelitziae, resulting in the death of all inoculated plants.

Genera of phytopathogenic fungi: GOPHY 3

“…Chlamydospores absent or solitary, globose, brown, thich-walled, guttulate. Sexual morph not observed (adapted from Aiello et al. 2017).…”

Cylindrocladiella peruviana and Pleiocarpon algeriense causing stem and crown rot on avocado (Persea americana)

“…These recent reports, including the present study, confirm that this fungus plays a role in causing diseases, although Cylindrocladiella spp. are not typically considered Regarding the other nectriaceous species reported in this study, Aiello et al (2017) described the new genus Pleiocarpon and P. strelitziae sp. nov. in Italy causing basal stem and root rot of the ornamental Strelitzia reginae.…”

“…nov. in Italy causing basal stem and root rot of the ornamental Strelitzia reginae. Pathogenicity tests demonstrated the aggressive pathogenic nature of P. strelitziae, resulting in mortality of all inoculated test plants within 2 months (Aiello et al 2017). Recently, two new species of Pleiocarpon have been described; in particular P. livistonae from Livistona rotundifolia (Arecaceae) in Sri Lanka, causing root and corm rot (Marin-Felix et al 2019a), and P. algeriense isolated in Algeria from grapevine cuttings with black-foot disease (Aigoun-Mouhous et al 2019).…”

“…In detail, 12 inoculated plants for each fungal isolate were arranged in a randomized complete block design (RCBD) with three replicates, each consisting of four inoculated seedlings. To this aim, a piece of bark was removed at the base of the stem with a 6 mm diameter cork-borer and 6-mm-diameter mycelial plugs taken from a 12-day-old fungal colony were applied as previously reported (Aiello et al 2014(Aiello et al , 2015(Aiello et al , 2017. The wounds were covered with Parafilm to prevent desiccation.…”

The complete mitochondrial genome of Ilyonectria sp. (Hypocreales: Hypocreomycetidae)

“…The Ilyonectria radicola complex is a group of soil fungi that is widely distributed in the world (Farh et al 2018). Over a dozen species have been described in this complex (Aiello et al 2017;Cabral et al 2012a). These fungi were reported to be associated with the symptoms of root rot on a broad range of herbaceous and woody host plants, such as ginseng, azalea, poplar, spruce, and apple, but also in stems or cankers of diseased trees (Cabral et al 2012b;Chaverri et al 2011).…”