Applications of Germicidal Ultraviolet Light as a Tool for Fire Blight Management (Erwinia amylovora) in Apple Plantings.
Phytopathology
; 113(12): 2215-2221, 2023 Dec.
Article
em En
| MEDLINE
| ID: mdl-37606320
ABSTRACT
Nighttime applications of germicidal UV light (UV-C) have been used to suppress several fungal diseases of plants, but less is known of UV-C's potential to suppress bacterial plant pathogens. Fire blight of apple and pear, caused by the bacterium Erwinia amylovora, is difficult to suppress using cultural practices, antibiotics, and host resistance. We therefore investigated the potential of UV-C as an additional means to manage the disease. Laboratory assays confirmed that in vitro exposure of cultures E. amylovora to UV-C at doses ranging from 0 to 400 J/m2 in the absence of visible light was more than 200% as effective as cultures exposed to visible light after the same UV-C treatments. In a 2-year orchard study, we demonstrated that with only two nighttime applications of UV-C at 200 J/m2 made at bloom resulted in an incidence of blossom blight and shoot blight equivalent to the results viewed when antibiotic and biopesticide commercial standards were applied. In vitro dose-response studies indicated consistency in pathogen response to suppressive UV-C doses, including pathogen isolates that were resistant to streptomycin. Based on these results, UV-C may be useful in managing bacterial populations with antibiotic resistance. Concurrent measurements of host growth after UV-C applications indicated that the dose required to suppress E. amylovora had no significant (P > 0.05) effects on foliar growth, shoot extension, internode length, or fruit finish but substantially reduced epiphytic populations of E. amylovora on host tissues.
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Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Malus
/
Erwinia amylovora
Tipo de estudo:
Guideline
Idioma:
En
Revista:
Phytopathology
Assunto da revista:
BOTANICA
Ano de publicação:
2023
Tipo de documento:
Article