Skip to main content
ARS Home » Pacific West Area » Corvallis, Oregon » Horticultural Crops Research Unit » Research » Research Project #435798

Research Project: Improving the Quality of Grapes, Other Fruits, and their Products through Agricultural Management

Location: Horticultural Crops Research Unit

2020 Annual Report

Objective 1: Identify, develop, and define analysis techniques to evaluate primary and secondary metabolites of fruit, fruit products, and wine. [NP 305; C1, PS1B] Sub-objective 1.A. Determine quality indicator metabolites and analytical methods for their analysis; evaluate and optimize new methods where insufficient data exists. Sub-objective 1.B. Deploy quality component measurements to optimize agricultural practices targeted at improving product quality. Objective 2: Integrate canopy- and fruit-specific management practices in grapes and berries to enhance crop productivity and fruit quality. [NP 305; C1, PS1B] Sub-objective 2.A. Determine development of fruit quality parameters as driven by the interaction between temperature and the timing of temperature anomalies during critical periods of fruit development. Sub-objective 2.B. Quantify standard industry pruning methods for grapevines and develop formal pruning standards necessary to achieve targeted goals for canopy structure; evaluate efficacy of manual pruning and algorithm-driven mechanical systems to achieve canopy structure goals. Sub-objective 2.C. Define canopy and fruit temperature thresholds leading to reduced fruit marketability in drip-irrigated blueberry fields. Objective 3: Develop cultural management strategies that mitigate the impact of abiotic stresses (drought and cold) in winegrapes. [NP 305; C1, PS1B] Sub-objective 3.A. Determine how irrigation spatial delivery, frequency, and amount affect the photosynthesis, water use efficiency, crop load and berry maturity of winegrapes. Sub-objective 3.B. Determine the influence of seasonal water deficit on cold acclimation during bud dormancy in winegrapes.

Project objectives will be accomplished by integrating research across three core disciplines: food chemistry- phytochemical analysis, plant-microclimate interactions, and crop physiology. A systematic approach in targeted fruit quality compound analysis to predict the magnitude by which climate and cultural factors impact fruit quality components will be used. This approach will allow us to improve and define analytical methods for plant metabolite analysis that advance our comprehension of the relationships among canopy management, canopy microclimate, water management, and vine cold hardiness and their effects on fruit development, fruit quality components, and vine physiology. If weather interferes with experimental treatments and sampling, experiments will be adjusted and extended an additional growing season.

Progress Report
This is the final report for project 2071-21000-052-00D, "Improving the Quality of Grapes, Other Fruits, and their Products through Agricultural Management," which has been replaced by new project 2072-21000-057-00D, "Improved Fruit, Grape and Wine Products through Precision Agriculture and Quality Component Evaluation." During the previous two years, selected chemical and field methods were employed for exploring the relationships between agricultural practices, abiotic stresses, biotic stresses, genotypes/cultivars, and their effect on fruit quality components important to agriculture or food systems. For the new project plan (2020-2025), ARS scientists in Parma, Idaho (worksite of Corvallis, Oregon) have proposed agricultural management, food production, and safety practice improvements to advance fruit and fruit product quality, benefiting growers, fruit processors, researchers, and consumers. This work will help sustain U.S. agriculture’s economic position in a globally competitive marketplace. In support of Objective 1, work continued on the analytical methods and guidelines for phenolic (also known as natural compound, phytochemicals, secondary metabolite) isolation and separation of ingredients used in food/dietary supplements for authenticity, quality, and safety. The methods, and access to authentic botanical specimens, allowed the proper phenolic identification and quality determination in commercial products containing cranberry, black raspberry, red raspberry, blueberry, strawberry, cherry, lingonberry, and acai fruit. Examinations of acceptance criteria for analytical methods of (primary and secondary) metabolites, important in elderberry products, are underway. These phenolic identification techniques also provided detailed anthocyanin (red pigment) profiles for newly released cultivars and genotypes of blackberry, red raspberry, black raspberry, strawberry, and blueberry developed by USDA. Future experiments are already planned to enhance upcoming cultivars of blackberry, red raspberry, black raspberry, strawberry, and blueberry with improved disease resistance and higher anthocyanin levels compared to currently available commercial cultivars. Detailed anthocyanin profiles of newly released cultivars are also essential for raw material characteristics, fruit-based products quality, authenticity, and food safety work. Health conscious consumers are also interested in the phenolic data of these new cultivars. Results from this work will guide fruit growers, dietary supplement ingredient suppliers, dietary supplement manufacturers, and consumer selections. We continued to work on a black raspberry breeding project to find a much-needed commercial replacement cultivar (less disease prone, high yielding, and high anthocyanin levels). Exemplars were field evaluated and fruits were collected. Black raspberry quality components important in perceived sweetness, acidity, and color were analyzed in these fruit samples. Work is ongoing to link these quality components with plant traits and associated genes. This will also reinforce the data on black raspberry sugar composition, and help dismiss the myth that Rubus fruit are high in sugar alcohol (that might cause discomfort if consumed in high quantity). Work was conducted on how biotic and abiotic stressors impact basil plant. We continued to investigate several basil cultivars’ response to low quality irrigation water (different salt types and amounts), mycorrhizal fungi colonization, nutrient availability, and plant growth substrates that affect plant yield and basil phenolics (phytochemicals). Further work is planned on strawberry plant with varying growing systems. In support of Objectives 1 and 2, work was conducted on how vineyard management and biotic/abiotic stressors alter wine grape quality components important for a healthy fermentation. We examined how cover crop managements, vine nutrient status, and vine virus status independently influence wine grape quality. Phenolic analysis is ongoing on samples obtained from the deficit vine nutrient project. Vine virus identification in commercial Idaho vineyards was the first step towards constructing virus diagnostic tools, tailored to the growing area, that can be used to mitigate future losses from vine virus infection. Research on how specific vine viruses influence healthy fermentation and quality components is underway. Information from this work will allow growers to make decisions regarding vineyard cover crop selection, tillage, vine nutrient regime, and vine rouging without decreasing grape quality and reducing production costs. Critical vacancies prevented significant progress on Objectives 2 and 3.

1. First report of Grapevine Red Blotch virus in Idaho. Some grapevine viruses are harmful to the U.S. wine grape industry, a $6 billion business. Some of these viruses are detrimental to grapevine health, crop load ratio, fruit characteristics, and ultimately to wine quality, while others cause only minor issues. ARS scientists in Parma, Idaho, with University of Idaho collaborators, conducted research on grapevine viruses in collaboration with commercial Idaho grape growers. This work is the first report on the presence of Grapevine Red Blotch Virus (GRBV) in Idaho commercial vineyards. Multiple years of sampling and testing for GRBV indicate the spread of this virus is limited in Idaho. These findings can be used by the grape industry for vineyard replanting decision making.

2. What’s really in your acai products. Anthocyanins are important natural pigments that contribute to the appearance of fruit, and to the anticipated quality characteristics of many fruit products. Acai (not native to the United States and mainly imported) products are commercially promoted to have health benefits due to high anthocyanin levels. An ARS scientist in Parma, Idaho, sampled market available acai food products and dietary supplements and analyzed them for individual anthocyanins and content. Twenty percent of the acai products examined had problematic anthocyanin profiles. The overall anthocyanin content of the acai products was lower than what can be obtained from common fresh and frozen U.S.-grown berries. Anthocyanin profiling can still be used in dietary supplement quality assurance, but systems to improve fruit-based dietary supplement quality are needed from source material to final products. The global acai market is estimated to be around $700 million.

3. Black raspberry plants rating standards. Black raspberry is an important caneberry fruit crop in the Pacific Northwest. ARS scientists in Parma, Idaho, and Corvallis, Oregon, along with multiple University collaborators, completed a multi-state project to phenotype 42 traits in two black raspberry mapping populations in 11 geographically distinct locations. A summary of a range of traits including important phenological stages, flowering, plant and fruit characteristics, and fruit chemistry traits, was obtained. Trait dependent variations across populations, locations, and years were observed. This phenotypic data will aid commercial and research plant breeders to further make black raspberry plants available to stakeholders.

Review Publications
Thompson, B., Eid, S., Vander Pol, D., Lee, J., Karasev, A.V. 2019. First report of grapevine red blotch virus in Idaho grapevines. Plant Disease. 103(10):2704.
Lee, J. 2019. Anthocyanins of acai products in the United States. NFS Journal. 14-15:14-21.
Bradish, C., Bushakra, J., Robbins, L., Karaaoac, E., Sabrina, T., Willard, J.L., Perkins-Veazie, P., Lee, J., Scheerens, J., Weber, C., Dossett, M., Bassil, N.V., Finn, C.E., Fernandez, G. 2020. Standardized phenotyping in black raspberry. Journal of American Pomological Society. 74(1):2-17.
Finn, C.E., Strik, B.C., Yorgey, B.M., Peterson, M.E., Jones, P.A., Buller, G., Serce, S., Lee, J., Bassil, N.V., Martin, R.R. 2020. ‘Eclipse’ thornless semi-erect blackberry. HortScience. 55(5):749-754.