Biological and Genetic Characterizations of a Novel Lytic ΦFifi106 against Indigenous Erwinia amylovora and Evaluation of the Control of Fire Blight in Apple Plants

Abstract

Erwinia amylovora is a devastating phytobacterium causing fire blight in the Rosaceae family. In this study, ΦFifi106, isolated from pear orchard soil, was further purified and characterized, and its efficacy for the control of fire blight in apple plants was evaluated. Its genomic analysis revealed that it consisted of 84,405 bp and forty-six functional ORFs, without any genes encoding antibiotic resistance, virulence, and lysogenicity. The phage was classified into the genus Kolesnikvirus of the subfamily Ounavirinae. ΦFifi106 specifically infected indigenous E. amylovora and E. pyrifoliae. The lytic activity of ΦFifi106 was stable under temperature and pH ranges of 4–50 °C and 4–10, as well as the exposure to ultraviolet irradiation for 6 h. ΦFifi106 had a latent period of 20 min and a burst size of 310 ± 30 PFU/infected cell. ΦFifi106 efficiently inhibited E. amylovora YKB 14808 at a multiplicity of infection (MOI) of 0.1 for 16 h. Finally, the pretreatment of ΦFifi106 at an MOI of 1000 efficiently reduced disease incidence to 37.0% and disease severity to 0.4 in M9 apple plants. This study addressed the use of ΦFifi106 as a novel, safe, efficient, and effective alternative to control fire blight in apple plants.

First European Erwinia amylovora Lytic Bacteriophage Cocktails Effective in the Host: Characterization and Prospects for Fire Blight Biocontrol

“…Finally, in this analysis, based on complete genomes, another noteworthy result was observed: the new E. amylovora phage isolates from Mediterranean settings show a significant similarity to other E. amylovora phages isolated in Belarus (OM522317), France (OQ818707), Switzerland [ 35 ], and South Korea [ 88 ]. This finding suggests that phage species within this clade, in addition to potentially being specific to E. amylovora , exhibit a low degree of genetic divergence, similar to what is observed in the pangenome of E. amylovora .…”

Isolation and Characterization of a Lytic Bacteriophage RH-42-1 of Erwinia amylovora from Orchard Soil in China

“…Jo et al [ 36 ] isolated the fire blight bacteriophage pEp_SNUABM_03, which showed tolerance to temperatures up to 40 °C and pH levels between 4 and 9. Choe et al [ 37 ] isolated the fire blight bacteriophage ΦFifi106, which maintained certain activity at temperatures up to 50 °C, pH levels between 4 and 11, and under 6 h of UV irradiation.…”

Long-Lasting Silver Nanoparticles Synthesized with Tagetes erecta and Their Antibacterial Activity against Erwinia amylovora, a Serious Rosaceous Pathogen

“…The "fire blight" bacteria attack buds and flowers, reducing significantly the production of pears and apples around the world. For this reason, E. amylovora has been classified as a quarantine organism in several countries [23,26,27].…”