Colletotrichum spp. causing anthracnose on ornamental plants in northern Italy

Abstract

Species of Colletotrichum are considered among the most important plant pathogens, saprobes and endophytes on a wide range of ornamentals, fruits and vegetables. Several Colletotrichum species have been reported in nurseries and public or private gardens in northern Italy. In this study, the occurrence, diversity and pathogenicity of Colletotrichum spp. associated with several ornamental hosts was explored. Survey were carried out during the 2013–2019 period in Piedmont, Italy. A total of 22 Colletotrichum isolates were collected from symptomatic leaves and stems of two Campanula spp., Ceanothus thyrsiflorus, Coreopsis lanceolata, Cyclamen persicum, Hydrangea paniculata, Liquidambar styraciflua, Mahonia aquifolium and Rhyncospermum jasminoides. A multi-locus phylogeny was established based on the basis of three genomic loci (gapdh, act and tub2). The pathogenicity of selected, representative isolates was tested. Colletotrichum isolates were identified as members of four important species complexes: Acutatum, Gloeosporioides, Dematium and Destructivum. Colletotrichum fioriniae, C. nymphaeae and C. fuscum were found in association with leaf lesions of Mahonia aquifolium, Campanula rapunculoides and Coreopsis lanceolata, respectively. Colletotrichum lineola, C. grossum and C. cigarro were isolated from Campanula trachelium, Rhyncospermum jasminoides and Liquidambar styraciflua, respectively. Colletotrichum fructicola was found to be responsible of anthracnose of Ceanothus thyrsiflorus, Hydrangea paniculata, Cyclamen persicum and Liquidambar styraciflua. All the tested isolates were pathogenic and reproduced identical symptoms to those observed in private gardens and nurseries. The present study improves our understanding of Colletotrichum spp. associated with different ornamental hosts and provides useful information for an effective disease management programme.

Effects of Cropping Practice on Bupleurum Chinense Rhizosphere Microbial Community

“…In contrast, some potentially pathogenic microorganisms, such as Cercophora [39], Alternaria, Paraphoma, Cladosporium [40], Monographella [41], Hydropisphaera [42], and Colletotrichum were signi cantly ampli ed. For example, Alternaria and Paraphoma can cause root rot of B. chinense [43][44], and Colletotrichum can infect leaves to produce disease spots [45]. These pathogenic microorganisms not only signi cantly reduce the relative abundance of bene cial bacteria in the eld, but also affected the normal growth of B. chinense.…”

Pest categorisation of Colletotrichum fructicola

“…Molecular methods, such as multilocus gene (e.g. ITS, tub2 , GS, gapdh , cmdse ) sequencing analysis, are available in the literature (Zhu et al., 2015 ; Li et al., 2016a , b ; Giblin et al., 2018 ; Grammen et al., 2019 ) and may be used in combination with morphology‐based methods for the identification of C. fructicola (Guarnaccia et al., 2021 ). However, it is worth noting that ITS sequences do not separate C. fructicola from C. aeschynomenes and some C. siamense isolates.…”

“…In Asia, the pathogen is reported from China (Jiang et al., 2014 ; Zhang et al., 2015 ; de Silva et al., 2019 ; Guarnaccia et al., 2021 ), Iran (Arzanlou et al., 2015 ), Japan (Shoji et al., 2014 ; Gan et al., 2016 ), Korea Republic (Paul et al., 2014 ; Lim et al., 2020 ), India (Sharma and Shenoy, 2013 ; Saini et al., 2016 ; de Silva et al., 2019 ), Taiwan (de Silva et al., 2019 ; Wu et al., 2020 ), Thailand (Weir et al., 2012 ; de Silva et al., 2019 ; Guarnaccia et al., 2021 ), Israel (Sharma et al., 2017 ) and Indonesia (Weir et al., 2012 ).…”

“…In Italy, the pathogen was detected for the first time in 2013 causing fruit rot on 5‐ to 10‐year‐old avocado ( Persea americana ; cv Hass) trees grown in four orchards in Catania province (eastern Sicily) (Guarnaccia et al., 2016 ). In 2019, C. fructicola was reported to cause anthracnose on aromatic and ornamental plants grown in nurseries located in northern Italy (near Biella) (Guarnaccia et al., 2021 ). In the same year, the pathogen was reported to cause a severe outbreak of fruit rot in commercial ‘Pink Lady’ apple orchards in the region Emilia‐Romagna (northern Italy) (Wenneker et al., 2021 ).…”

“…( 2019 ) Ceanothus thyrsiflorus Rhamnaceae Blue blossom ceanothus Guarnaccia et al. ( 2021 ) Citrullus vulgaris Cucurbitaceae Watermelon CDFA ( 2016 ) Citrus bergamia Rutaceae Bergamot orange Peng et al. ( 2012 ) Citrus reticulata Rutaceae Mandarin orange Huang et al.…”