Erwinia spp. from pome fruit trees: similarities and differences among pathogenic and non-pathogenic species

Abstract

The number of described pathogenic and nonpathogenic Erwinia species associated with pome fruit trees, especially pear trees, has increased in recent years, but updated comparative information about their similarities and differences is scarce. The causal agent of the fire blight disease of rosaceous plants, Erwinia amylovora, is the most studied species of this genus. Recently described species that are pathogenic to pear trees include Erwinia pyrifoliae in Korea and Japan, Erwinia spp. in Japan, and Erwinia piriflorinigrans in Spain. E. pyrifoliae causes symptoms that are indistinguishable from those of fire blight in Asian pear trees, Erwinia spp. from Japan cause black lesions on several cultivars of pear trees, and E. piriflorinigrans causes necrosis of only pear blossoms. All these novel species share some phenotypic and genetic characteristics with E. amylovora. Non-pathogenic Erwinia species are Erwinia billingiae and Erwinia tasmaniensis that have also been described on pome fruits; however, less information is available on these species. We present an updated review on the phenotypic and molecular characteristics, habitat, pathogenicity, and epidemiology of E. amylovora, E. pyrifoliae, Erwinia spp. from Japan, E. piriflorinigrans, E. billingiae, and E. tasmaniensis. In addition, the interaction of these species with pome fruit trees is discussed.

Conventional and Real-Time PCRs for Detection of Erwinia piriflorinigrans Allow Its Distinction from the Fire Blight Pathogen, Erwinia amylovora

“…Thus, a polyphasic approach is required to identify each pathogen accurately. Recent genomic analyses have provided information on the taxonomic positions of Erwinia species and insight into their evolution (16,17). These data strongly support the need for unambiguous identification methods.…”

“…On the basis of our recent findings, we expect that this bacterium is also present in other countries and has been mistakenly identified as E. amylovora or another Erwinia species, as occurred with some Erwinia spp. in Japan (17). The techniques developed in this study could also be used in surveys that would shed light on the current distribution of E. piriflorinigrans inside and outside of Spain, in epidemiological studies that would provide information about the life cycle of E. piriflorinigrans in different hosts and plant tissues, and in exploration of the interaction of E. piriflorinigrans with E. amylovora.…”

Erwinia pyrifoliae, a new pathogen on strawberry in the Netherlands1

“…However, the host range of E. pyrifoliae has been reported to be broader than Pyrus pyrifolia [15]. Although the occurrence of this pathogen on strawberry or indeed its presence has not been reported outside Asia, its real distribution could be rather uncertain because specific surveys for E. pyrifoliae are seldom [16].…”

“…The possible risk of E. pyrifoliae for pome fruit in the Netherlands will also be investigated. Several species within the genus Erwinia are pathogenic to pome fruit trees [16]. The fire blight disease of rosaceous plants was initially described in the late eighteenth century, and its causal agent (Erwinia amylovora) was identified in the late nineteenth century.…”

Biocontrol of Fusarium circinatum Infection of Young Pinus radiata Trees

“…are mainly plant pathogens, however, E. billingiae is part of the normal commensal microbiota of pome fruit trees and is well adapted to plant colonization including resistance to environmental stresses [39][40][41]. It is an antagonist of the closely related species E. amylovora that causes fire blight on apples and pears [42].…”