Diaporthe diversity and pathogenicity revealed from a broad survey of grapevine diseases in Europe

Abstract

Species of Diaporthe are considered important plant pathogens, saprobes, and endophytes on a wide range of plant hosts. Several species are well-known on grapevines, either as agents of pre- or post-harvest infections, including Phomopsis cane and leaf spot, cane bleaching, swelling arm and trunk cankers. In this study we explore the occurrence, diversity and pathogenicity of Diaporthe spp. associated with Vitis vinifera in major grape production areas of Europe and Israel, focusing on nurseries and vineyards. Surveys were conducted in Croatia, Czech Republic, France, Hungary, Israel, Italy, Spain and the UK. A total of 175 Diaporthe strains were isolated from asymptomatic and symptomatic shoots, branches and trunks. A multi-locus phylogeny was established based on five genomic loci (ITS, tef1, cal, his3 and tub2), and the morphological characters of the isolates were determined. Preliminary pathogenicity tests were performed on green grapevine shoots with representative isolates. The most commonly isolated species were D. eres and D. ampelina. Four new Diaporthe species described here as D. bohemiae, D. celeris, D. hispaniae and D. hungariae were found associated with affected vines. Pathogenicity tests revealed D. baccae, D. celeris, D. hispaniae and D. hungariae as pathogens of grapevines. No symptoms were caused by D. bohemiae. This study represents the first report of D. ambigua and D. baccae on grapevines in Europe. The present study improves our understanding of the species associated with several disease symptoms on V. vinifera plants, and provides useful information for effective disease management.

High diversity of Diaporthe species associated with dieback diseases in China, with twelve new species described

“…Thus, during the past decade, a polyphasic approach, employing multi-locus DNA data together with morphology and ecology, has been employed for species boundaries in the genus (Crous et al 2012, Udayanga et al 2014a, b, Huang et al 2015, Gao et al 2016, 2017, Guarnaccia and Crous 2017, 2018, Hyde et al 2017, 2018, Yang et al 2017a, b, 2018, Guarnaccia et al 2018, Jayawardena et al 2018, Perera et al 2018a, b, Tibpromma et al 2018, Wanasinghe et al 2018). …”

“…The genus Diaporthe Nitschke represents a cosmopolitan group of fungi occupying diverse ecological behaviour as plant pathogens, endophytes and saprobes (Muralli et al 2006, Rossman et al 2007, Garcia-Reyne et al 2011, Udayanga et al 2011, 2012a, b, 2014a, b, 2015, Gomes et al 2013, Fan et al 2015, Du et al 2016, Dissanayake et al 2017b, Guarnaccia and Crous 2017, Yang et al 2017a, b, 2018, Guarnaccia et al 2018, Marin-Felix et al 2018). Diaporthe species are responsible for diseases on a wide range of plant hosts, including agricultural crops, forest trees and ornamentals, some of which are economically important.…”

“…Although the classification of Diaporthe has been on-going, species are currently being identified based on a combination of morphological, cultural, phytopathological and phylogenetical analyses (Gomes et al 2013, Huang et al 2013, 2015, Udayanga et al 2014a, b, 2015, Fan et al 2015, Du et al 2016, Gao et al 2016, 2017, Guarnaccia and Crous 2017, Hyde et al 2017, 2018, Guarnaccia et al 2018, Jayawardena et al 2018, Perera et al 2018a, b, Tibpromma et al 2018, Wanasinghe et al 2018). However, fungi isolated from forest trees in China were recorded in old fungal literature without any living culture and molecular data (Teng 1963, Tai 1979, Wei 1979).…”

Phomopsis husk rot of macadamia in Australia and South Africa caused by novel Diaporthe species

“…Many studies on a range of economically important crops such as grapevine (Guarnaccia et al , 2018), sunflower (Thompson et al , 2011), soybean (Santos et al , 2011), and citrus (Guarnaccia and Crous, 2017), have shown that different Diaporthe species can cause the same disease symptoms. PHR of macadamia caused by D .…”

“…Many new Diaporthe species have been described in recent years, based on multilocus phylogenetic studies (Gao et al , 2017; Guarnaccia et al , 2018; Long et al , 2019). Unfortunately, it is rare that much new or useful biological information accompanies these newly described taxa.…”