Plectosphaerella species associated with root and collar rots of horticultural crops in southern Italy

Abstract

Plectosphaerella cucumerina, most frequently encountered in its Plectosporium state, is well known as a pathogen of several plant species causing fruit, root and collar rot, and collapse. It is considered to pose a serious threat to melon (Cucumis melo) production in Italy. In the present study, an intensive sampling of diseased cucurbits as well as tomato and bell pepper was done and the fungal pathogens present on them were isolated. Phylogenetic relationships of the isolates were determined through a study of ribosomal RNA gene sequences (ITS cluster and D1/D2 domain of the 28S rRNA gene). Combining morphological, culture and molecular data, six species were distinguished. One of these (Pa. cucumerina) is already known. Four new species are described as Plectosphaerella citrullae, Pa. pauciseptata, Pa. plurivora and Pa. ramiseptata. Acremonium cucurbitacearum is shown to be a synonym of Nodulisporium melonis and is transferred to Plectosphaerella as Plectosphaerella melonis comb. nov. A further three known species of Plectosporium are recombined in Plectosphaerella.

Metagenomic analysis of soil fungal communities on Ulleungdo and Dokdo Islands

“…The genus Plectosphaerella of the class Sordariomycetes was more abundant on Seodo (2.03%) than on Ulleungdo (0.06%) or Dongdo (0.17%). Members of this genus are known as plant pathogenic fungi (Carlucci et al, 2012). In the class Agaricomycetes of Basidiomycota, the genera Craterellus, Lactarius, Mycena, and Russula were detected only in the Ulleungdo sample, whereas the genus Omphalina was detected only in the Seodo sample.…”

Leaf and spathe spot of calla lily caused by an undescribed species of Plectosphaerella

“…According to a report by Carlucci et al (2012), the pathogen resembles P. plurivora and P. pauciseptata. However, little morphological difference is apparent among some species of Plectosphaerella; the species criteria are obscure.…”

“…According to these characteristics, this fungus appeared to be a Plectosphaerella sp. (Carlucci et al 2012). Perithecia and chlamydospores were absent.…”

“…MAFF 238967 was obtained from the National Institute of Agrobiological Sciences (NIAS) Genebank, Japan. Carlucci et al (2012) reported that colony diameters Bootstrap values (1000 replicates) are shown on branches. Accessions from the DDBJ/EMBL/GenBank database are in parentheses after scientific names.…”

Spore Density Determines Infection Strategy by the Plant Pathogenic Fungus Plectosphaerella cucumerina

“…The fungus can cause sudden death and blight disease in a variety of crops (Chen et al, 1999;Harrington et al, 2000). Because P. cucumerina can infect Arabidopsis leaves, the P. cucumerina-Arabidopsis interaction has emerged as a popular model system in which to study plant defense reactions to necrotrophic fungi (BerrocalLobo et al, 2002;Ton and Mauch-Mani, 2004;Carlucci et al, 2012;Ramos et al, 2013). Various studies have shown that Arabidopsis deploys a wide range of inducible defense strategies against P. cucumerina, including JA-, SA-, ABA-, and auxin-dependent defenses, glucosinolates (Tierens et al, 2001;Sánchez-Vallet et al, 2010;Gamir et al, 2014;Pastor et al, 2014), callose deposition (García-Andrade et al, 2011;Gamir et al, 2012Gamir et al, , 2014Sánchez-Vallet et al, 2012), and ROS (Tierens et al, 2002;Sánchez-Vallet et al, 2010;Barna et al, 2012;Gamir et al, 2012Gamir et al, , 2014Pastor et al, 2014).…”