2007 Annual Report 1a.Objectives (from AD-416) Develop irrigation practices that support sustainable production of high quality wine and juice grapes. Determine effects of the variations in temperature found in the field environment on budburst, flowering, and fruit quality of grapevines. Develop and test an automated method for estimating yield in grapevines. Evaluate non-grafted wine grape varieties and clones grown in a cool, semiarid climate for horticultural characteristics, berry composition, and wine quality. 1b.Approach (from AD-416) A number of approaches will be pursued to better understand grapevine production and fruit quality in the irrigated production areas of the Pacific Northwest. Variety and clonal differences will be assessed under deficit irrigation. Fruit quality parameters, including anthocyanins and volatiles, will be quantified by refractometer, high-performance liquid chromatography, and gas chromatography-mass spectroscopy, as appropriate. Sensory analysis will follow established protocols. Heat-balance sap flow gauges and whole-vine enclosures will be used to directly measure transpiration and photosynthesis. Growth variables will be assessed by standard metrics. A novel method of yield estimation will be developed by exploiting the mechanics of the trellis system. Formerly 5358-21000-025-00D (11/03). 4.Accomplishments “Terroir” analysis facilitates designation of new American Viticultural Area. Wine grape production in non-traditional climatic regions presents unique opportunities and challenges for research as well as commercial production. A descriptive analysis of geologic, soil, climatic characteristics, and viticultural practices of the Western Snake River Plain was conducted by scientists in HCRU, Corvallis, OR in conjunction with scientists from Boise State University as a first step towards understanding production opportunities and constraints in this non-traditional production region. For the scientific community, the work was published in GeoScience Canada, an international peer-reviewed journal. This information was used directly by the Idaho Grape Growers and Wine Producers Commission to petition the Alcohol and Tobacco Tax and Trad Bureau for the first designated American Vviticultural Area in the state of Idaho, awarded in 2007. This accomplishment addresses the integrated production system component of NP 305 (Crop Production), in that viticulture acreage is an increasingly important commercial alternative fruit crop in Idaho. American Viticultural Area designations can have significant long term economic impact through marketing name recognition, Problem Statement C)Sustainable Cropping Systems and D) Economic Evaluation. Low-Cost Shielding to Minimize Radiation Errors of Temperature Sensors in the Field. We understand the importance of shielding temperature sensors from the sun (solar radiation) so that accurate measurements of air temperature and plant temperature can be made. There are excellent commercial shields available but at significant cost, making them prohibitively expensive to many agricultural scientists who need to run large numbers of temperature sensors at once. Plant scientists who conduct replicated field experiments, farm advisors, and others need prescriptive advice for building inexpensive and effective solar shields so that their temperature data are accurate. We applied the general physical principles that govern solar shielding to devise a number of low-cost shields that could be built in any plant science laboratory or workshop, and also illustrate advantages and pitfalls of various physical configurations. The cost of all 'home-built' solar shields was about 20 times less than that of a single commercial shield that is considered the 'gold standard' for weather stations, and one handmade shield that most closely approximated the performance of the expensive commercial shield was recommended for general applications. A shield similar to this would be useful for plant scientists or farm advisors who are constrained by small budgets and the need for large numbers of temperature sensors. NP305, Problem area IIc: Sensors and sensor technology. 5.Significant Activities that Support Special Target Populations None 6.Technology Transfer Number of non-peer reviewed presentations and proceedings 6 Number of newspaper articles and other presentations for non-science audiences 10 Review Publications Lee, J., Rennaker, C.D. 2007. Antioxidant capacity and stilbene contents of wines produced in the Snake River Valley of Idaho. Food Chemistry. 105:195-203. Shellie, K. 2007. Viticultural Performance of Red and White Wine Grape Cultivars in Southwestern Idaho, USA. HortTechnology. 17(4)595-603. Dragoni, D., Lakso, A.N., Piccioni, R.M., Tarara, J.M. 2006. Transpiration of grapevines in the humid northeastern United States. American Journal of Enology and Viticulture. 57(4):460-467.