Determining the Timing of Spore Release by Botryosphaeriaceae Species in Oregon Vineyards.

Botryosphaeria dieback, caused by a group of pathogens in the Botryosphaeriaceae family, is one of the most common grapevine trunk disease complexes (GTDs) found in Oregon vineyards. To understand the period of spores released by spp. in Oregon vineyards, four Burkard 7-day recording volumetric spore traps were placed in vineyard blocks in northern and southern Oregon.

Acidifying Spray Suspensions of Oxytetracycline and Kasugamycin Enhances Their Effectiveness for Fire Blight Control in Apple and Pear.

The stability of the fire blight control material, oxytetracycline, in water is strongly affected by pH, increasing with increasing acidity. From 2017 to 2021, pear and apple orchard trials were conducted to evaluate if acidic amendments to oxytetracycline sprays improve fire blight control. Compared with the water-treated control, infection suppression after two bloom applications of an acidified commercial oxytetracycline formulation averaged 85.

A Systematic Survey on Prevalence of Grapevine Trunk Disease Pathogens in Oregon Vineyards.

Grapevine trunk diseases (GTDs) are found in vineyards worldwide and can be caused by different fungal pathogens. To characterize types of GTDs in Oregon vineyards, and how the GTD pathogens' prevalence is affected by two geographical regions, a survey was conducted in which grapevine trunk samples were collected from 15 and 14 wine grape () vineyards in southern and northern Oregon, respectively. Fungal species were identified through culture and PCR-based methods.

Refinement of Nonantibiotic Spray Programs for Fire Blight Control in Organic Pome Fruit.

Fire blight-susceptible, certified organic pome fruit is produced on 9,000 ha in the Pacific Northwest region of the United States with acreage continuing to expand despite a 2014 prohibition on antibiotics as allowable materials for infection suppression. Nonantibiotic practices for fire blight pathogen suppression mirror conventional management, but the full-bloom-to-petal-fall period when antibiotics are typically sprayed for fire blight control continues to receive research scrutiny owing to drawbacks and weaknesses of alternative materials. As solitary treatments, effective nonantibiotic materials (e.

Morphological and Molecular Characterization of spp. Isolated from European Pears.

In a recent survey of post-harvest rot pathogens in European pear in Southern Oregon, spp. were frequently isolated from orchard samples of pear flowers and fruits. Morphological differences were observed within the isolated cultures.

Water Deficits Do Not Improve Fruit Quality in -Infected Grapevines ( L.).

Although deficit irrigation is used to improve fruit quality in healthy grapevines, it can potentially amplify negative effects of viral disease and reduce fruit quality in Grapevine Red Blotch Virus (GRBV) infected grapevines. Therefore, a 2-year field experiment was conducted to understand the interaction between GRBV infection and water deficits on disease development and vine physiology. Well-watered (WW) vines were irrigated at 100% of estimated crop evapotranspiration (ET), while water deficit (WD) vines received water at 66 and 50% ET in 2017 and 2018, respectively.