Response of Grapevine Defenses to UV—C Exposure

Bonomelli, Alexandra; Mercier, Laurence; Franchel, Jérôme; Baillieul, Fabienne; Benizri, Émile; Mauro, Marie-Claude

doi:10.5344/ajev.2004.55.1.51

Cited by 63 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is illustrated by the reasonably good fits of the disease severity progression data to power functions having the same exponent of 3.19. With respect to the UV-C treatments investigated in this study, the observed delays in onset of downy mildew may be attributed to increased resistance to downy mildew induced by the treatments pr ior to infection (Bonomelli et al, 2004). Even if this could be substantiated in further experiments, however, the observed effect was relatively small.…”

Section: Year 2 Field Datamentioning

confidence: 66%

Effectiveness of the Field Application of UV-C for Cucumber Downy Mildew Control

2022

View full text Add to dashboard Cite

There is growing interest in the application of ultraviolet (UV-C) energy to control crop pathogens. In the present study, the efficacies of UV-C treatments for controlling cucumber downy mildew (Pseudoperonospora cubensis) were investigated on a commercial farm in eastern Massachusetts, USA. Controlled doses of UV-C, delivered by a tractor-mounted array of sources, between 120 and 480 J·m-2 were applied and compared to conventional fungicide treatments as well as to untreated controls, for each of two consecutive years (2020 and 2021). Visual assessments of foliar disease severity in the trial plots were made several times from planting through the end of productive life. In contrast to the successful control of powdery mildew, the UV-C treatments for controlling cucumber downy mildew were not as successful as conventional fungicides. None of the UV-C treatments affected the overall progression rate of downy mildew once the disease became apparent, although disease onset was delayed slightly compared to untreated controls. This delay may have been due to UV-C induced resistance to infection by the host. Unlike powdery mildews, downy mildew spores from P. cubensis are darkly pigmented, possibly decreasing the efficacy of the UV-C treatments for controlling the disease. DM spores may also be only susceptible to UV exposure prior to encysting in the leaves of the host, thereby perhaps limiting the window of opportunity when UV-C treatments can be effective. Although not the primary focus of this study, the use of reflective mulch appeared to delay disease onset relative to black mulch in fields with significant sunlight exposure, perhaps due to lowering plant stress by maintaining a lower soil temperature.

show abstract

Section: Year 2 Field Datamentioning

confidence: 66%