Viticulture and Enology Extension News Washington State University

FALL 2011

CONTENTS Note from the Editor

VITICULTURE Summer has finally decided to show up, fashionably late. As the East Coast and Midwest recover from record high temperatures and an early harvest, we are still 2011-Season in Review...... Page 2 patiently waiting for full véraison. This truly is the calm before the storm….but lucky for us, that storm doesn’t equate to earthquakes, hurricanes or fall thunder- AgWeatherNet...... Page 3 storms. Life is generally pretty good this side of the Rockies. Mealybugs...... Page 4 Speaking of the good life, the Viticulture and Enology program is proud to an- BMSB...... Page 5 nounce that the new Wine Science Center on the WSU-TriCities Campus is taking postive steps forward. The Richland City Council has approved the formation of a Virus Update...... Page 6 Public Development Authority, and the Washington Wine Commision has voted to provide close to $7.5 million for its construction. Other fundraising efforts contin- Concord Report Card...... Page 7 ue with the Wine Campaign Committee led by Ted Baseler (CEO of Ste. Michelle Wine Estates), the Port of Benton, the City of Richland, and the WSU Foundation.

But back to the present: In this issue of VEEN, we have a wide breadth of topics. ENOLOGY Updates on the vintage, pests, programs; discussions on high-Brix wine making, and updates on new TTB regulations, just to name a few. Hopefully you enjoy Measuring Brix...... Page 8 this issue as much as I did in organizing it: We have a very busy Viticulture and TTB:Yeast Nutrients...... Page 8 Enology program here at Washington State University! Maceration...... Page 9 Michelle Moyer Viticulture Extension Specialist WSU Sensory Program...... Page 11 WSU-IAREC

V&E Certificate Program..... Page 12 Find us on the web: eViticulture...... Page 13 www.wine.wsu.edu/research-extension People Profiles...... Page 14 Information, when you need it. That is the power of the internet! Visit the WSU Viticulture and Enology Research and Extension website for valuable Calendar of Events ...... Page 14 information regarding research programs at WSU, timely news releases on topics that are important to your business, as well as information regarding upcoming workshops and meetings. EDITORS It is also a valuable site for downloading our most recent Extension publications, as well as finding archived articles and newsletters you can print on demand. Find quick links to AgWeatherNet, the Viticulture and Michelle Moyer, PhD Enology Certificate and Degree programs, as well as to other Viticulture and Enology related resources. Find us on Facebook! WSU Extension programs and employment are available to all without discrimination. Go to: and “Like” the page! Evidence of noncompliance may be reported www.facebook.com/WSU.Vit.Enol.Ext through your local WSU Extension office. 1 2011 Year in Review: Where was Summer? By Michelle Moyer, WSU-Prosser

If grape production was easy, we wouldn’t define wine by the Powdery Mildew vintage. This year presented WA viticulturists with a se- Powdery mildew control was also ries of challenges, challenges a challenge this year, due to near which are often only dealt with ideal temperatures and humidity on a decade scale. But chal- in the region for most of the grow- lenges, regardless of irritation ing season. Cooler temperatures or frustration, provide an op- around bloom also slowed develop- portunity to learn. In 2011, we ment, leaving clusters exposed in cannot deny the ample supply a susceptible state for longer than of teachable moments. normal (Fig. 2).

Growing Degree Days: What The common denominators in most doe it mean? places experiencing loss-of-control were: (i) extended spray intervals, Using growing degree days (ii) poor coverage, (iii) use of below (GDDs) to assess a growing -labeled rates, and (iv) less than de- season can be a helpful (see sirable control last year. related AgWeatherNet article Figure 1. Freeze damage from November 2010 and on page 3). However, there is February 2011 has been on everyone’s minds. In many Extended spray intervals leaves often a misunderstanding be- cases, dead trunks and cordons were not removed be- developing tissue exposed to po- fore suckers developed in the summer. Many vineyards tential infection. While extending tween the quantity, and quality, throughout the state faced tough retraining decisions this of those accumuated units. A spring. these intervals may save a spray in “hot” year (higher GDDs) does a normal year (think hot and dry), not necessarily mean favor- sented. Some people spot-retrained, 2011 was not normal. Just remem- able conditions for plant development. others broke out the bulldozers. How- ber, that under optimal conditions, the Grapes begin to shut down at tempera- ever, we do know that variability in- powdery mildew fungus can reproduce tures above 95°F, so while these tem- creases the costs of farming. As a gen- every 5 days, so tight intervals, espe- peratures result in higher GDD accu- eral rule of thumb, if variability within a cially during bloom, are critical. Poor mulation, they are not necessarily what managed unit starts to go beyond 30%, coverage and using low rates can re- is best for the plant. When nighttime then starting over to regain uniformity sult in the same thing: not having the temperatures routinely fall below 50°F, may be the best choice. proper amount of fungicide reaching a similar situation occurs. Ideally, lows the fungus. in the 60s and highs in the upper 80s A challenge that is often coupled to a to low 90s result in the highest “quality” retraining situation is managing sub- Coverage is key in powdery mildew of GDD accumulation. sequent vine vigor. Vine age needs to management, and appropriate rates be considered when determining the make sure that there is enough prod- How does this play into the big vintage number of suckers to be retained. In uct to control fungal development. Use picture? When we compare how vin- young plants, a limited root system re- appropriate canopy management tech- tages relate based on GDDs, we have duces the available nutrient reserves niques such as fruitzone leaf removal, to consider the extremes. While 2011 from which the vine can draw to sup- to help with spray penetration. Use appears to be three weeks behind port new shoot development. A similar the highest labeled rates of a product average based on GDDs, in terms of scenario is seen in older plants which if weather conditions are favorable for plant development, it looks to be closer might be contending with years of ac- PM development. to 5-7 days behind. The take home: cumulated stress and damage. While GDDs are a great way to get a continued on page 13 snapshot of how the season is pro- With vines that are about 5-15 years gressing, it is not a complete descriptor old, the established root system often of the current vintage’s growing (and provides more than enough nutrient quality) capacity. reserves, resulting in excessive shoot growth. This is especially true if insuffi- Freeze and Frost Damage cient suckers are left to redistribute this energy. Winter freeze damage from November 2010 and February 2011 were painfully On a related note, while the cool, wet visible in some parts of WA this spring spring temperatures were viewed un- (Fig. 1). Economic questions regard- favorably in terms of initial vine devel- ing the tipping point between individ- opment, they were likely a blessing in ual vine and entire vineyard retraining disguise. These conditions reduced were raised, and rightly so. Complete early-season water stress and likely replanting was also considered, but allowed for more thorough phloem re- Figure 2. Cool temperatures and higher- sourcing stock is a challenge in years covery. The cooler spring and summer than-normal humidity made for perfect like this one. Unfortunately, there are temperatures were strong influences weather conditions for powdery mildew in no real right and wrong answers to the on the healthy, and sometimes exces- 2011. Timing and coverage were every- plethora of situations that were pre- sive, canopy recovery this year. thing this season.

2 AgWeatherNet Update: www.weather.wsu.edu By Gerrit Hoogenboom, WSU-Prosser

Global warming in Washington? Since Table 1. July 2011 Daily Average Temperatures (˚F) for key weather stations in Washington. I took the position of Director of Ag- Location (Period of Record) Maximum Minimum Mean Anomaly WeatherNet in August of last year and moved from warm and balmy Geor- Prosser (WSU IAREC; 1990-2011) 83.6 51.8 68.6 -3.7 gia to Washington, people keep ask- Mabton East (2009-2011) 85.6 51.6 69.9 NA ing me if I have done “something” to the weather. First, we experienced the Port of Sunnyside (1993-2011) 84.1 51.4 68.8 NA Thanksgiving freeze last year, followed Moxee (1990-2011) 83.4 46.2 66.5 -3.5 by a cool spring and now a relatively cool summer. Mt. Vernon (WSU NWREC; 1994-2011) 69.6 51.6 60.1 -2 Wenatchee (WSU TFREC; 1994-2011) 82.5 56.6 70.4 -4.5 Trust me; weather is not really something you want to mess with. Gramling (Tri-Cities; 1989-2011) 83.4 54.5 69.3 -4.2 Walla Walla (1993-2011) 83.5 55.4 69.7 -4.1 The weather stations of AgWeatherNet Royal City East (2008-2011) 81.6 54.3 68 NA closely monitor the weather conditions across the state and hopefully many of you check the web site at www.weath- Table 2. Growing Degree Days (base 50°F) for 1 April- 17 August. er.wsu.edu on a regular basis. Our observations do indeed confirm that it Location 2011 2010 2009 Average has been cool and that it probably has Prosser (WSU IAREC)* 1436 1684 1939 1843 been one of the coolest springs and summers since the first weather station Port of Sunnyside* 1454 1758 2048 1883 was installed in 1988 (Fig. 1). Although Walla Walla* 1559 1782 2036 1967 this period only spans 23 years and is relatively short when evaluating local Mt. Vernon (WSU NWREC)** 832 939 1096 944 climate conditions, it does allow us to Paterson* 1669 1952 2264 2142 conduct comparisons with prior years. Outlook** 1538 1849 2191 2005 A summary for July for some of the Mattawa** 1694 1950 2228 2212 key stations in the region can be found Maryhill*** 1558 1849 2294 1989 in Table 1. Wenatchee has been the coldest with an average temperature Benton City West** 1592 1946 2227 2081 of 4.5°F below normal, followed by *=2006-2010 average, **=4 year average, ***=3 year average the Tri-Cities area which was 4.2°F below normal and Walla Walla which was 4.1°F below normal. Prosser was The plant is a great “integrator” of the is frequently used to express this is 3.7°F below normal and Moxee was local environment, especially soil and “growing degree days” (GDDs) Grow- 3.5°F below normal. weather conditions. One feature that ing degrees are the total number of degrees above a threshold value, which is 50°F for grapes. It is determined by cal- culating the average temperature and then subtracting the base temperature from the average temperature; a negative number will not be considered in this calculation and is usually ignored. A summary for the GDDs accumulat- ed since April 1 is shown in Table 2. A comparison is also provided with 2010, which was considered to be somewhat of a cool year, and 2009, a somewhat warm year. The average is based on the last four or five years, depending on the weather station location. The numbers clearly show what we all know: it has been cool since April. If your site is not shown in the table you can calcu- late your GDDs using one the tools on the AgWeatherNet website. AgWeatherNet will continue to closely monitor the growing degree days. Like Figure 1. The daily maximum and minimum temperatures since January 2011 for many of you, we hope that the first Prosser, WA. Graphs for other locations are available at: www.weather.wsu.edu. freeze will be late this year!

3 Research Update: Mealybugs in Washington Vineyards By Brian Bahder (PhD Student) and Doug Walsh, WSU-Prosser

The grape mealybug, Pseudo- was captured the first week of coccus maritimus, was first re- May. In 2011, the experimental ported in Washington State in design was changed to a com- 1950 by Kenneth Frick. Grapes plete randomized design so in the lower Yakima Valley were that there was only one treat- infested, and the grape mealy- ment per vineyard block, op- bug was found on other crops posed to all three treatments in (pears, apricots) in subsequent one vineyard. This will hopefully years. The initial concern about reduce confounding effects do the grape mealybug was fo- to proximity of different treat- cused on table grape produc- ments. Thus far, all sites have tion, where heavy infestations exhibited the same trend as last created large quantities of hon- year with flight peak occurring eydew that resulted in sooty mid June and no mealybugs mold development. Sooty mold, present for most of July. and the presence of mealybugs in the grape clusters, reduces Vines were field sampled for- the marketability of the crop. Figure 1. Grape Mealybug, Pseudococcus maritimus, on the crawlers and to monitor the rate Currently, direct damage is not underside of a Concord leaf. of development. Based on the the only concern for producers. data from the first flight, there Current research has demonstrated second generation emerged around does not appear to be a difference in that the grape mealybug can trans- the end of July and early August, with the average number of males per trap mit grapevine leafroll associated vi- their peak flight period in mid August. between the treatments using this new ruses (GLRaV-3). Grapevine leafroll The second flight lasted longer than experimental design. This indicates that disease can cause yield loss of up to the first, and adults were captured one trap is just as effective as eight traps 60%. until mid October. At every site, the for monitoring populations. To repeat the treatment with eight traps caught more experiment for determining male flight In 2007, the sex pheromone of the males than the treatment with four distance, traps will be placed outside of grape mealybug was isolated and traps, which caught more than the one vineyard research blocks, starting at 300 became commercially available for trap treatment. The difference between ft. They will be moved every week to get vineyard monitoring. The availability the average number of mealybugs per a more accurate idea of how far males of this pheromone thus lead to the trap in all treatments also followed this are capable of flying. development of a research projected trend but to a lesser degree. These focused on determining the flights sites were in a randomized complete Data provided from this research will timing of the grape mealybug in order block design, and there could have hopefully provide useful information to to deploy more effective management been resulting competition between help successfully monitor vineyards for strategies. Starting in 2009, Delta the treatments. grape mealybug infestations. It should sticky traps with pheromone-imbibed also provide a timeframe for when to treat septa were placed in both ‘Concord’ Traps that were placed outside of the for mealybugs, as treatments should be juice grape vineyards and in wine vineyard to determine the flight dis- focused on control of crawlers, as that is grape vineyards. The manufacturer- tance of adult males had male cap- when they are most vulnerable to insec- recommended trap density is 1 trap tures at 300 to 600 ft away from the ticide applications. per 30 vineyard acres. For the exper- surrounding vine- iment, traps were placed at densities yards. Closer to of one, four, and eight traps per 30 the vineyard (300 acres, to determine the true density, ft), the males were and subsequent efficacy, of the traps. clustered around the pheromone These traps were also used to deter- septa, indicating mine: (i) the number of generations that they had con- per growing season, (ii) when these trolled flight and generations peaked, (iii) when crawl- were not random- ers were emerging, (iv) the timing ly blown into the of first adult emergence, and (v) the trap. Farther from flight distance of adult males. the vineyard (600 ft) males were not In 2010, traps were collected weekly clustered, sug- and the number of adult male mealy- gesting they may bugs was recorded from 20 May until have been blown 27 Oct. Mealybug capture occurred into the traps. during the first week of deployment. In 2011 all traps In 2010, there were two generations were set up mid of mealybugs. The first generation April in order to that emerged from the overwintering capture the first stage matured and had an adult peak flight, and the Figure 2. Sticky trap with pheromone septa placed in a Concord vine- period in the middle of June. The first mealybug yard to attract adult male mealybugs.

4 Update on the Brown Marmorated Stink Bug By Gwen Hoheisel, WSU Benton-Franklin County Extension

The Brown Marmorated Stink Bug specimens were caught in the Portland- (BMSB; Halyomorpha halys) was first Vancouver area. In 2011, hundreds of detected in the United States in the mid traps (Figure 1) were deployed in both 1990’s, but has recently made making eastern and western Washington and national headlines because of the dam- Oregon by researchers, extension fac- age is has caused in commercial crops ulty, and master gardeners. and homes on the East Coast. Every- one, from homeowners to commercial Based on experiences from the East growers, is affected by this pest. Coast, the natural spread of BMSB is slow, but people can unwittingly transport the bug in vehicles and shipments. Therefore, our initial trapping is heavily focused on high risk areas like camp grounds, mini-storage units, and rest areas. The complete lifecycle of BMSB in the PNW is still unknown. However, Figure 2. BMSB can be identified with the researchers believe combinaion of black and white abdomen that they will have one stripes, smooth shoulders and striped anten- generation per year, as nae. opposed to two generations that can occur in The Pest Management Transition Proj- warmer climates. ect has a useful online identification tool for stinkbugs that will help people Figure 1. Trap used by researchs (left) in the Pacific North Unlike native stink bugs, distinguish between the natives and West. Thraps for homeowners (right) are also sold at major BMSB can complete an BMSB (http://pmtp.wsu.edu/BMSB. retailers on the East Coast. Both are baited with a phero- entire lifecycle in the html). mone lure and a killng agent strip. vineyard or orchard. A benefit to this is that the No one knows when BMSB will invade immature nymph stage of the BMSB is vineyards. Optimistically, if the patterns With a host list spanning everything more susceptible to insecticides, but of population growth in the PNW mimic from ornamental trees (e.g. walnut, timing and good coverage will still be those of the Eastern U.S., it could be maple, redbud), to vegetables (e.g. critical for control. several years before economic impacts tomatoes, corn, asparagus), and fruit are seen. However, first detection and (e.g. small fruit, stone fruit, pome fruit), Growers and crop consultants should monitoring is critical so that research- both gardeners and commercial grow- familiarize themselves with the differ- ers can gain as much knowledge as ers have reason for concern. It’s feed ences between native stink bugs and possible before this becomes a larger habit can cause severe damage and BMSB. BMSB has distinctly stripped problem. distortion to developing fruit. Home- abdomen and antennae as well as owners dislike BMSB because it will a smooth shoulder (i.e. no teeth or If you suspect you have BMSB, bring aggregate and overwinter in houses spikes) (Figure 2). adult specimens into your local exten- by the hundreds, much like the multi- sion office or research center. colored Asian ladybug. There are many native stink bugs that can have similar characteristics, but all In 2010, researchers and master gar- of the aforementioned need to be pres- deners began to look for BMSB in ent on the insect for positive identifca- western Oregon and Washington, and tion of BMSB.

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5 Virus Update: The Status of Washington Vineyards By Naidu Rayapati, WSU-Prosser In recent years, rapid expansion of the grape and wine industry in WA has predisposed its sustainable growth to debilitating virus and virus-like diseases. Since winegrape (Vitis vinifera) cultivars are clon- ally propagated to main- tain trueness-to-type, and vegetative cuttings are used by growers for new plantings, viruses and virus-like agents have been primarily disseminated into new areas via movement of planting materials. Diseases caused by viruses and virus-like agents cannot be controlled by therapeutic agents (analogous to Figure 1. Grape viruses documented in WA vineyards. About 2000 samples were tested for the following fungicides for control- viruses: GLRaV-1, GLRaV-2, RG strain of GLRaV-2 (GLRaV-2-RG), GLRaV-3, GLRaV-4,GLRaV -5, and ling powdery mildew), GLRaV-9, GRSPaV, GVA, GVB, and GFLV. GLRaV-3 is the most widely distributed among the viruses. therefore they must be controlled by prevention. and 2009 and tested for the presence mixed infections of grapevine viruses. of grapevine viruses. The majority of With this objective, the grape virology these samples came from different Among the ten grapevine leafroll-as- program at WSU-IAREC has been sur- American Viticultural Areas (AVAs) in sociated viruses (GLRaVs) reported veying grower vineyards for viruses the Columbia Valley and a few samples worldwide, six GLRaVs (GLRaV-1, -2, since 2005. Since grapevine leafroll were from the Puget Sound AVA. -3, -4, -5, and -9) were detected during disease (GLRD; see Extension Bulle- our surveys (Fig. 1). In addition, three tin EB2027E for details) has been rec- Samples were tested for different viruses associated with Rugose Wood ognized as a major constraint to wine grapevine viruses. The sequences Complex (Grapevine rupestris stem grape production, surveys were con- were compared with corresponding se- pitting-associated virus [GRSPaV], ducted mainly for this disease in both quences of known grapevine viruses in Grapevine virus A [GVA], and Grape- red and white cultivars. In the case of GenBank (an online repository of ge- vine virus B [GVB]), grapevine fanleaf red cultivars, leaf samples showing netic information) to precisely identify virus (GFLV; the causal agent of fan- characteristic symptoms of grapevine viruses and viroids present in the test leaf disease), Grapevine fleck virus leafroll disease (green veins and inter- sample. The data obtained from these and Grapevine Syrah Virus 1 were de- veinal reddening and downward rolling studies were also analyzed to assess tected in some wine grape cultivars ex- of leaf margins) were collected be- molecular diversity among different vi- hibiting GLRD symptoms. Among the tween August and October every year. ruses and to document the incidence of continued on page 7 Due to variation, leaf samples showing a wide range of discolorations were also collected. In some cases, leaf samples were collected from suspect grapevines, even though these vines were not showing any apparent GLRD symptoms. Since white cultivars do not exhibit typical GLRD symptoms, leaf samples were collected randomly from individual grapevines. In addition, vineyard blocks were monitored for symptoms caused by other viral diseases such as grapevine fanleaf. For this, vineyard blocks were monitored for fanleaf disease symptoms during June and July, since disease symptoms are more apparent during this time. Approximately 2000 samples from different winegrape cultivars planted Figure 2. Vitis vinifera ‘Merlot’ showing GLRD symptoms. This vine tested positive for in 35 vineyard blocks were collected GLRaV-3 and GVA, the putative agent of grapevine kober stem grooving disorder of the over a five year period between 2005 Rugose Wood complex. 6 A Report Card for Sustainable Concord Production in WA By Joan Davenport, WSU-Prosser Farm accountability of general grow- Cooperative fieldman Craig Bardwell collaborative team to help evaluate the ing practices has become a big con- to develop a pre-proposal to fund this true “sustainability” of these practices cern, and marketing focus, for retailers effort, through the Washington State by identifying a team of growers who across the globe. The Concord juice Department of Agriculture (WSDA). will go through the initial evaluation out- industry faces the same issue that all WSDA has received a block grant from lined in our Washington State Concord juice industries are facing: Product the federal government (USDA) under Sustainability Report Card. We will vendors are asking the manufacturers the Specialty Crops Research Initia- then use this information to revise the to demonstrate that the products they tive (SCRI) to fund projects that are fo- Report Card document for ease of use. are selling have been grown with rec- cused on state needs. This will be a three year reiterative pro- ognition of environmental protection cess to refine the Report Card. and quality. In January, we received word that our pre-proposal was approved and then At the end of this process, Washington The Concord grape industry in Wash- expanded our work to include other growers and processors will be able ington recognizes that disease and processors to develop a complete pro- to document how their growing prac- insect pressure in our vineyards are posal. In June, we were notified that tices, or their contracts growing prac- lower than other growing regions in the this proposal had been approved for tices, are doing relative to the Report country. However, simple recognition is funding. Card standards, and will be able to use not enough. Documenting this fact, and this information to help continue to sell our associated management practices, We are taking a collaborative approach and market our high quality juice grape are required. New York and Michigan between WSU and Washington Con- products! have already developed sustainability cord grape processors for this project. programs for their juice industry, and Our research and extension team will If you have questions or wish to be in- now it is our turn. develop a list of common practices that volved in the pilot program, please do will be defined and evaluated based on not hesitate to contact me. E-mail al- To this end, a team of WSU Extension the national industry standards for sus- ways works best – [email protected]. and Research Scientists (Drs. Michelle tainability. This list will be modified us- Moyer, Doug Walsh, and I) worked ing consultations with processors. After collaboratively with National Grape this initial step, we plan on creating a Virus Update cont. from page 6 ruses indicating presence of geneti- to date of grapevine viruses in WA vine- cally diverse isolates in WA vineyards. yards. The results are benefiting certified nurseries and Northwest Grape In addition, a limited number of samples Foundation Service located at IAREC were tested for the presence of five vi- in maintaining ‘clean’ planting materials roids reported in grapevines worldwide. for the benefit of the wine grape indus- Australian grapevine viroid (AGVd), try. It is important to note that monitor- Hop stunt viroid (HSVd), Grapevine ing for viruses and virus-like agents yellow speckle viroid-1 (GYSVd-1) is essential to ensure vine health in and Grapevine yellow speckle viroid our vineyards. The results have been -2 (GYSVd-2) were detected in sev- shared with industry and regulatory eral wine grape cultivars affected with agencies for increased knowledge of GLRD. Among them, HSVd was found virus diseases and promotion of ef- Figure 3. Vitis vinifera ‘Pinot noir’ showing symptoms of GLRD and grapevine fanleaf to be widespread in different cultivars. fective sanitation practices includ- disease. This vine tested positive for GL- GYSVd-1 was found to be the second ing planting of certified materials by RaV-3 and GFLV underscoring the need for most frequently observed viroid fol- growers. multiple testing in indexing programs. lowed by AGVd and GYSVd-2. Acknowledgements: viruses documented so far, GLRaV-3 Molecular analysis indicated that these This work was supported, in part, by was found to be the most prevalent four viroids are highly similar to those WSU’s ARC and Extension Team- and widely distributed. Further analysis reported from other regions. These vi- based internal competitive grant, Mem- of the data showed that many of these roids may cause synergistic effects in bers of the Wine Advisory Committee viruses are present in individual grape- mixed infections with other grapevine of the WA Wine Commission, WSDA vines as single and/or mixed infections viruses. Although differences were ob- Assessment Funds, USDA-ARS North- (Figs. 2 and 3). These mixed infections served in the frequency of AGVd, HSVd, west Center for Small Fruits Research, were found occurring in different com- GYSVd-1 and GYSVd-2, it should be USDA-NIFA Viticulture Consortium- binations. It should be noted that the noted that these results from a limited West and USDA-NIFA SCRI Award No. presence of other viruses is yet to be number of samples may not reflect the 2009-51181-06027. Drs. Olufemi Alabi, ascertained. Studies on genetic vari- true picture of the presence of viroids Linga Gutha, Sridhar Jarugula, Gandhi ability of natural populations of grape- in wine grape cultivars planted in the Karthikeyan, Tefera Mekuria, Marilyn vine viruses such as GLRaV-1, GL- region. The economic impact of these Soule, and Mr. Sudarsana Poojari have RaV-2, GRSPaV and GFLV collected viroids remains to be evaluated. contributed to the data presented in from different vineyard blocks showed this article. the highly variable nature of these vi- This is the most comprehensive study

7 Brix and Alcohol: A Simple Measurement? By Jim Harbertson, WSU-Prosser Most of us are familiar with the con- in our lab have shown that under con- sure of the initial alcohol in your tank. version of sugar into alcohol during trolled conditions, sugar that normally Even with all of the aforementioned fermentation. However, with the ad- measure 25 Brix would measure about variables, these methods will still only vent of so-called “high Brix” winemak- 24.1 Brix with 2% (v/v) ethanol present. provide an estimate, since they cannot ing, some winemakers are reporting It seems completely unlikely that 2% account for potential released sugar in conversion rates of sugar to alcohol (v/v) ethanol would be produced in an unbroken berries, or ethanol evapora- during fermentation which are beyond evening just after crushing, but 0.5% tion during fermentation and storage. theoretical values. So how is this pos- (v/v) would be within reason. This, of sible? This article will discuss some of course, would alter your conversion In conclusion, one of the simplest re- the factors that can lead to this mis- ratio considerably because you would lationships that enologists have used take. still think the initial Brix was unchanged for years has become more complex (even though in practical terms, you with the advent of “high-Brix” winemak- Theoretical conversion is based on the have less Brix). ing. Several factors can lead to the conversion of a single 6-carbon sugar miscalculation of greater conversion (glucose), to two each of ethanol and An additional mistake is assuming all of rates of sugar to alcohol than theoreti- carbon dioxide. The theoretical yield your fruit was adequately crushed. One cally possible. Measuring the glucose of ethanol is 51.1% by weight and difficulty in dealing with high-Brix fruit, to fructose ratio can be used as an in- 65% by volume. There is the opinion is that it tends to only partially crush, dicator that fermentation has begun in that theoretical yields are lowered to even when it goes through a conven- fruit or in tanks, and initial measures of 43-47% weight and 54-59% by vol- tional destemmer-crusher. As the fruit ethanol can be used to help remedy the ume, due to yeast formation of other begins to get overripe (fruit naturally situation. composed used to survive the ethanol stop accumulating sugar after 25˚Brix, environment they produce. This opin- additional sugar comes from dehydra- ion, however, needs to be considered tion), it can shrivel and these shriveled Legal Status of in context: the ability of different yeast berries become more difficult to crush Yeast Nutrients Changed strains to survive ethanol toxicity does because of reduced turgor pressure. varies, but the variance among most This results in whole berries slipping popular yeast strains sold only is only through the rollers of your crushing Winemakers have sometimes used 0.5% of extra ethanol, and the typical mechanism. When this happens, it yeast nutrients to limit risks associated maximum limit of ethanol produced is may cause an underestimation of sugar with problem alcoholic fermentations. ~14.5% (v/v). concentration, as these whole berries Available from technical suppliers, will break and release sugar at different nutrients are commonly sold as pro- The most popular equation to calcu- times during the winemaking process. prietary blends containing a nitrogen late conversions assumes that the Some wineries even complain of sig- source (frequently diammonium phos- majority of soluble solids in grapes nificant sugar increases after pressing phate), vitamins, minerals, and other is sugar (glucose and fructose). This because of the high number of unbro- ingredients. However, some of these is optimistically calculated as soluble ken berries in the ferment. blends were technically illegal for use solids (Brix) x 0.51. Some equations in the USA. Although the ingredients attempt to account for other solids The advent of more specific measures were considered to be generally re- (not sugars) that contribute to Brix of sugar evaluation such as glucose garded as safe (GRAS), most were not measure, but this is variable (depen- and fructose has added an extra level included on the list of materials legal dent on vintage, variety and vine- of interest. Typically, measures of glu- to treat grape wine maintained by the yard). Additionally, because ethanol cose and fructose are done at the end Trade and Tobacco Bureau (TTB). evaporates during fermentation and of fermentation to measure residual barrel aging, the basic conversion ra- sugar. It can also be done to evaluate Supported by the WA Wine Advisory tio between sugar and ethanol is tran- troublesome ferments, as yeast tend to Committee and others, the lab of C.G. sient in nature. be glucophilic and leave more fructose Edwards has conducted experiments behind. Some wineries have begun over a number of years to determine Getting the initial soluble solids mea- measuring the glucose to fructose ratio optimal concentrations of vitamins surement correct is often one of the in the fruit and have noticed that the ra- important for Saccharomyces. Such first areas of error. Sampling can be tio tends to slightly favor fructose. nutrients included biotin, pantothenic difficult in large acreage vineyards acid, thiamin, and pyridoxine. With this due to variability in ripening. Many The berry accumulates fructose and supporting evidence, a petition was wineries use the harvest measure of glucose on a 1:1 ratio (from sucrose) recently prepared to the Trade and Brix as a guide to what to expect in and does not have any preferential use Tobacco Bureau (TTB) to approve the the tank. However, in most cases, Brix of either sugar. So the ratio in the ei- use of these nutrients. As of August 1, measured after crushing is quite dif- ther the fruit samples or after crushing, 2011, TTB approved the petition, and ferent than that taken at harvest, likely can be used as a means to determining these vitamins may be legally used to due to a lapse in time from crushing to if fermentation in your sample or tank assist fermentation in the USA. For the measurement (often waiting overnight has begun. Since yeast will preferen- list of approved materials, please see after crushing, and taking the sample tially transport glucose inside their cell, (http://www.ttb.gov/wine/wine_treat- in the morning). This can translate to a higher fructose to glucose ratio would ing_materials.shtml). a small amount of ethanol being pro- indicate that fermentation has begun. Thank you to the WA Wine Advisory Committee, duced, as fermentation has already American Vineyard Foundation, Lallemand Inc., begun. Measures of soluble solids by Finally, there are methods (distillation, and others for support of this research as well density meters are relatively insensi- gas chromatography, infra red) for as all the individuals involved in this work (J.K. Fellman, K.M. Hagen, A. Ortiz-Julien, J.P. Os- tive to the presence of ethanol, and measuring ethanol in the presence of borne, G. Specht, L. Van de Water, X.-D. Wang, this can be problematic. Measures sugar, which can provide you a mea- and others).

8 Maceration Part 1: Focus on Phenolics By Federico Casassa (PhD Student) and Jim Harbertson, WSU-Prosser The maceration process, the contact of skins, and seeds. Recently, skins and seeds with juice during red we have found that under winemaking (Fig. 1), is an intriguing as- extended maceration condi- pect of modern Enology. Maceration is tions, such decrease in mo- recognized as a critical step in defining nomeric anthocyanins can wine style, but some fundamental ques- be partially explained by the tions still remain: What substances are incorporation of these mono- extracted and what are their impact?; mers into polymeric pigments How do these compounds evolve over [2] (Greek poly=many). time and interact with each other?; and How does this evolution influence the Tannins. The term “tannin” is wine style? often used loosely to describe a class of phenolic com- This article, the first in a series on mac- pounds able to precipitate eration, will focus on phenolics. proteins (such as the ones found in human saliva), thus Extraction and Evolution of Pheno- eliciting the tactile sensation lics during Maceration called “astringency”. These are located in both grape The maceration process can be divid- skins (about 20%) and seeds ed into three distinct phases. Figure 2 (about 80%) and can be show these phases as a function of skin monomers, oligomers (Greek contact time, along with the theoretical oligos=a few, i.e. composed extraction of anthocyanins, tannins, fla- by more than one but less vonols and polysaccharides during red than five units) or polymers. wine maceration. Tannins react with antho- Anthocyanins. Anthocyanins are mono- cyanins during aging, result- meric (Greek monos=one, meros=part) ing in color stabilization and and glycosilated compounds (Greek the observed “mellowing” of glukus=sugar, i.e. with a glucose mol- wine astringency with aging. Figure 1. Detail of the formation of the cap (on top) ecule attached) located in the grape The extraction of these com- and colored juice (bottom) of a fermentation vessel of Malbec wine during the second day of skin contact. skin. They are responsible for color, pounds is complex and their Note the thickness of the cap and the early extraction and possibly, modulation of astringen- interaction with anthocyanins, of anthocyanins as evidenced by the intense red color. cy upon reaction with tannins [1]. pectins, and polysaccharides is still not fully understood. In Anthocyanins are also highly sensitive the first stage, when the fermentation the seeds while the skins contribute to pH: only 20-25% of the total avail- medium is essentially aqueous, skin with the remaining. Therefore, more able anthocyanin pool displays the typi- tannins are predominantly extracted. than half of the tannin content of wine cal red color at wine pH, the rest are in Sensorially speaking, lower molecular (and thus much of its astringency) uncolored forms. Maximum extraction weight skin tannins are slightly bitter comes from the seeds. is typically observed between the 4th and astringent, whereas polymers of and 5th day of skin contact [2], but this about 30 units are more astringent than There is still much to be learn about the can occur earlier (e.g. Malbec) or later smaller skin tannins. The first stage of chemical fate of tannins during wine- (e.g. Pinot noir). tannin extraction is followed by a sec- making. Recent research conducted ond “transition” stage, under increas- at UC-Davis, WSU, and the Australian In addition to time, temperature also ing ethanol levels, which continues the Wine Research Institute is unveiling plays a major role in anthocyanin ex- extraction of skin tannins together with several new dimensions on the chem- traction. Maceration is a diffusion- the initiation of seed tannin extraction. istry of these compounds. driven process, with the diffusion rate There is still a third phase, post-macer- of anthocyanins (and most phenolic ation, in which the extraction driven by Contrary to popular belief, it appears classes, for that matter) increasing al- seed tannins [3]. that it is just the tannin concentration most linearly between 60 to 95°F. itself, and not the origin of the tannin, Seed tannins are chemically differ- that explains perceived astringency. Anthocyanins, by virtue of the sugar ent from skin tannins in that they are Second, the extraction of seed tannins attached to them, are water-soluble shorter (from monomers up to 8 or 9 can range from 5 up to 65% [4], sug- molecules, and in the situation of cold- units). Sensory-wise, seed tannins are gesting that large differences on the soaking, up to 70% of the extractable bitter in the case of monomers and cer- wine tannin content may be explained anthocyanins can be recovered in the tain dimers, and also more coarse and by a higher or lower extraction of seed wine. astringent than skin tannins of similar tannins. In fact, under extended mac- size. eration conditions, up to 80% of the A sharp decrease in the concentration tannin pool available in the seeds can of anthocyanins is observed during Contingent upon variety and macera- be extracted. post-maceration (Fig. 2), due to degra- tion technique, it is estimated that from dation reactions and to an electrostatic the initial pool of tannins present in the Finally, it appears that when it comes to phenomenon leading to the absorp- berry, only 10 or 20% of it is extracted tannins, it is not all about extraction. In- tion of these pigments into yeast cells, [4]. From these, 60 or 65% come from continued on page 10

9 Maceration Part 1 continued from page 9

Figure 2. Theoretical extraction kinetics of the major phenolic compounds during the three phases of maceration. Modified from Zamora [6]. deed, the cell walls of the berry meso- documented effects as protective col- Please see future VEEN issues for Part carp (flesh) can absorb large amounts loids and as (beneficial) modulators of 2: Color Evolution, and Part 3: Focus of tannins. The ethanol, which is pres- astringency. on Aroma. ent towards the end of alcoholic fermentation, may aid the desorption of Early during maceration, these com- References them from the cell walls [4]. Conse- pounds are extracted primarily from the quently, it is thought that desorption berry cell walls. Maximum extraction, [1] Cheynier, V., et al. 2006. Structure and is what drives the documented “over- however, is attained after alcoholic fer- properties of wine pigments and tannins. extraction” of these compounds at the mentation and during aging, contingent AJEV 57:298-305. end of an extended maceration. upon autolysis (Greek autos=self and lysis=breakdown) of Saccharomyces [2] Casassa, L.F, et al. 2011. Unraveling Flavonols. Located mainly in the skin, cerevisiae cells [5]. the effects of extended maceration in Mer- these are light-yellow planar mol- lot wines with different ethanol levels. Proc. ecules. At concentrations above 200 Conclusion Am. Soc. Enol. Vit. Annual Meeting, Mon- mg/L they can elicit bitterness and a terrey, Cal. pp 70. mild astringent response. Although the Maceration is the most decisive phase [3] Harbertson, J.F., et al. 2009. Chemical initial flavonol pool in grapes can be for phenolic management in red wines and sensory effects of saignée, water addi- high, under practical winemaking con- and defines wine style. Since so many tion, and extended maceration on high Brix ditions no more than 50-60 mg/L are variables come into play, winemakers must. AJEV 60:450-460. actually extracted [2]. focus much of their technical efforts on those 8, 10 or 20 days of maceration. [4] Adams, D.O., and Scholz, R.C. 2008. Flavonols are also involved in a phe- Tannins - the problem of extraction. Proc. nomenon known as “copigmentation”, Skin contact time and temperature are 13th Australian Wine Industry Tech. Conf. Aus. Soc. for Vit. and Oenology. Adelaide, protecting anthocyanins from being arguably the two most important vari- Aus. pp. 160-164. discolored (e.g. by effect of pH swings) ables, readily altering the proportions or from oxidation. of the major phenolic classes that end [5] Guadalupe, Z., Martínez, L., and B. up in the wine. Knowledge of the under- Ayestarán. 2010. Yeast mannoproteins in Polysaccharides. These are heteroge- lying physical and chemical processes red winemaking: effect on polysaccharide, neous mixtures of proteins and poly- that occur during maceration allows the polyphenolic, and color composition. AJEV meric carbohydrate structures that can winemaker to adapt this process to the 61:191-199. readily interact with polyphenols. Lo- style of wine that is being sought and cated both in the grape and yeast cell ultimately, to what consumers expect to [6] Zamora, F. 2003. Elaboración y crianza del vino tinto: Aspectos científicos y prác- walls, polysaccharides and mannopro- find in the glass. ticos; AMV Ediciones, Mundi-Prensa: Ma- teins are among the highest molecular drid, España, 225 pp. weight compounds in wine, with well- This article is one in a three part series. 10 Program Update: Wine Sensory By Carolyn Ross, WSU-Pullman

The sensory and analytical facilities mine the impact of tannin concentra- different times, with the time required to have been a busy place in the School tion on the wine sensory attributes. reach maximum intensity being shorter of Food Science in Pullman! Below Syrah and Cabernet Sauvignon wines for fruity/floral compounds and longer are descriptions of three wine research were spiked at 1:8 ratio of 4-EG:4-EP, for the mushroom and oaky flavors. projects that are currently being con- with grape tannin added at 500, 1000 ducted in the Ross lab. and 1500 mg/L catechin equivalents. Duration of the perception was also Trained panelists evaluated these shorter for the fruity/floral compounds Effects of Tannin and 4-Ethylphe- wines for medicinal, spicy, leather and compared to the other compounds. nol and 4-Ethylguaiacol on Sensory fruity aroma intensity. In Cabernet Following trained panel evaluations, Properties of WA Cabernet Sauvi- Sauvignon, increased tannin concen- consumers (n=60) evaluated three gnon and Syrah tration resulted in increased medicinal commercial WA Chardonnay wines and lower fruity aroma intensity. that varied in the application of oak dur- Brettanomyces bruxellensis (“brett”) ing winemaking. Results showed that contamination is often considered a Sarah Michaux is the MS student in- consumers found a difference in finish wine fault. “Brett” contamination is as- volved with the project, along with col- between the “no oak” Chardonnay and sociated with increased concentrations laboration with Dr. Charlie Edwards. the heavily oaked Chardonnay. This of 4-ethylphenol (4-EP) and 4-ethyl- She gave an oral presentation of her study provides the first rigorous exami- guaiacol (4-EG) in the wine. These research at the 2011 American Soci- nation of wine finish and its relationship compounds have been linked with ety of Enology and Viticulture Annual with both the presence of different fla- negative sensory properties including Meeting. vor compounds and consumer accep- increased “Band-Aid”, “barnyard” and tance. “medicinal” aromas, with the suppres- Perception of Wine Finish in White sion of fruity attributes. Wines Emily Goodstein is the MS student currently involved with this project. This The first objective of this study was to Wine finish is defined as the linger- study will be presented at the 2011 determine a ratio of 4-EP to 4-EG that ing taste that follows the swallowing Pangborn Sensory Symposium (Toron- would lead to consumer rejection of of wine. It is believed that certain fla- to, ON). Emily is currently employed at WA Syrah and Cabernet Sauvignon vors are associated with the length of Milne Fruit in Prosser, WA. wines. In these wines, two consumer the wine finish, with fruity/floral flavor panels (n=50) were conducted that associated with shorter finish and oak, Impact of wine matrix components evaluated three ratios of 4-EP to 4-EG: spice, and earthy flavors associated on the aroma and flavor perception 1:4 (100µg/L 4-EG: 400µg/L 4-EP), 1:8 with a longer finish. of red wine (100µg/L 4-EG: 800µg/L 4-EP) and 1:12 (100µg/L 4-EG: 1200µg/L 4-EP). Finish is also said to be closely relat- The objective of this research project is For both wine varietals, a significant ed to wine quality, with a longer finish to examine the interaction of wine ma- decrease in consumer preference was associated with higher quality wines. trix components, particularly ethanol, observed at the 1:8 ratio, suggest- However, these associations between on the chemical and sensory properties ing consumer preference of 4-EP and wine finish and flavor and quality have of red wine. To address this research 4-EG is between the 1:4 and 1:8 ratios. not been approached in the scientific question, a number of graduate stu- literature. The objective of this study dents have worked various aspects of As wine composition may influence was to determine how finish varies with this project. 4-EG and 4-EP perception in red wine, the presence of various flavor com- the second objective was to deter- pounds in white wine, and to relate the Medy Villamor (Ph.D) has examined concept of finish to model wines and the impact of wine consumer accep- matrix on the recovery of eight aroma tance. compounds. The model wine varied in its composition of ethanol, fructose Using time intensity and tannin concentration. All of these methods, a trained matrix components were involved in panel (n=10) de- complex interactions impacting the termined the per- recovery of the aroma compounds. Al- ception of finish for though both fructose and tannin levels four different flavor influenced the recovery of odorants in compounds in a model wine solutions, their impact was model wine and heavily dependent on the level of etha- white wine system. nol. Higher ethanol, tannin and fruc- These compounds tose levels favored retention of larger, included ethyl hex- hydrophobic aroma compounds. Thus anoate (fruity), lin- the lowest concentration of odorant in alool (floral), oak the headspace was found in the pres- lactone (oaky), ence of high fructose and tannin at and 1-octen-3-ol 16% ethanol. (mushroom). The time-intensity re- These interactions are important as sults showed that they may reduce the perception of Wine sensory studies require a lot of set up. Here, a graduate the four com- these aromas in wine during sniffing student prepares for a tasting panel. pounds finished at continued on page 12

11 Program Update continued from page 11 and consumption. Collaborating with The wine treatment significantly -im The results suggested that the sensory Drs. Charlie Edwards and Jim Harbert- pacted the final ethanol concentration modifications that saignee and watering son, Medy has presented her research of the wine, with ethanol concentra- back techniques have on the final wine at several scientific meetings, including tions ranging from 15.7% in the con- may improve consumer acceptance Washington Association of Wine Grape trol treatment to 12.2% in the 19°Brix with regard to certain attributes. Taken Growers and the 2010 and 2011 An- treatment. Sensory difference testing together, these results demonstrate the nual Meeting of the American Society showed that consumers were able to influence of ethanol and other matrix of Enology and Viticulture. distinguish between the treatments. In components on aroma compound re- consumer acceptance testing, differ- covery, sensory aroma threshold and Moving beyond a model system, this ences in aroma, astringency and alco- consumer acceptance of specific wine project has also sought to answer the hol burn acceptance were found, with sensory attributes. question of differences in chemical and lower acceptance for the control wine. sensory properties in an actual wine. Allison Beall and Anne Secor are the To this end, the impact of watering back Trained panel evaluation of these MS students who worked on this as- and saignee on the final properties of wines showed that watering back in- pect of the project. This research has the wine were examined. creased the intensity of some attribute been presented at the Washington aromas (nutty notes) but decreased Association of Wine Grape Growers Wine prepared: Treatment 1 was a the intensity of other aromas (vegetal, Annual Meeting. Allison is currently control (no treatment applied, 27°Brix). caramel and spicy notes), bitterness employed at Commercial Creamery Treatment 2 was a watered back and alcohol burn. Further, the impact (Spokane, WA). treatment, adding water to the must of saignee and watering back was also to 23°Brix. Treatment 3 involved first examined in wines that were industri- Studies continue in the sensory eval- watering back the must to 23°Brix, ally prepared. uation lab. Please give me a call followed by the addition of sucrose (509-335-2438) or send me an e-mail to raise the sugar back to the original Among the treatments, control (22°or ([email protected]) if you have any 27°Brix. Treatment 4 was a watered 23˚Brix), bleed to 7% and bleed to re- questions or would like to be a partici- back treatment, adding water to bring place, trained panelists were able to pant in the studies. the °Brix down to 19°Brix. Treatment 5 identify specific aroma and flavor differ- was watered back to 19°Brix, with su- ences while consumers displayed dif- crose added to raise the °Brix back to ferences in acceptance. the original 27°Brix.

V&E Certificate Program Continues to Grow By Theresa Beaver, Certificate Program Coordinator The WSU Viticulture and Enology Cer- hearing from certificate graduates; for students. All of this contributes to tificate Program originally started in many who write to share their success- the quality of the education received 2003. Based out of WSU-IAREC in es and offer thanks to the program. by students, and continues to generate Prosser, it was designed as an onsite Dana Trabun, owner/winemaker of appreciation, as expressed by Martin class to increase the skills of those in Barili Cellars in Spokane, WA wrote to Gorski, from North 42 Degrees Estate the WA Wine Industry. In 2007, the tell me that, “I love to encourage those Winery in Windsor, Ontario. “Setting program went online and is now reach- who are interested in the wine-making up the lab for my winery, I found my- ing students from around the globe. process to look into the WSU Enology self ever grateful for the quality of the While residents of WA still have prior- Certificate Program as it provided- in instruction I received from the team ity enrollment and make up about half valuable information in each and every in the Enology Certificate Program - of the students in each class, students course that helped us toward building a thanks again”. are now coming from far and wide with successful winery”. representation from 21 states, four Ca- To date, 350 students have enrolled nadian Provinces, and this year, from Anthony Buchanan wrote to tell me in the certificate program and most as far away as Middlesex, England. that he is enjoying his position as wine- have successfully obtained a Certifi- maker at Paradise Ranch Ice Wines cate of Completion. In addition to the In addition to the 11 online courses and Soaring Eagle Winery in Penticton, Certificate Programs, the courses are spanning over 18 months, students British Columbia. “I couldn't have done available to take independently and attend three weekend workshops with it without my Education from WSU.” individually for those who only need hands-on activities, tours and visits Buchanan wrote. “I want to thank you information from a few of the topics, with winery and vineyard owners. The and all the instructors for providing me and do not want to attend the weekend students rave about these weekend with a strong foundation”. events. For more information on the events and report that the hands-on Self-Directed courses follow the link on experience and the connections they The instructors in the Certificate Pro- our website http://wine.wsu.edu/educa- make with fellow students, WSU Fac- gram consist of WSU Extension Spe- tion/certificate/. At this link you can also ulty and those in the wine industry, are cialists, Teaching and Research Fac- see the many wineries and vineyards an invaluable part of the program. ulty, and industry professionals. Many that have been started by Certificate winemakers have opened their cellars graduates. Be sure and say ‘hi’ if you As the Program Coordinator, I enjoy for field trips and hands-on experience visit them.

12 eViticulture: National Resource for Viticulture Information

The national online viticulture resource, with them to provide an easier, and to name a few. Stafne said often indi- eViticulture (eviticulture.org), offers the more comprehensive, experience for viduals possess more than one exper- latest in science-based information for the grower. Our end goal is to be the tise area, and expertise areas overlap, viticulturists. ‘one-stop-shop’ for viticulture informa- allowing for overall strength in numer- tion.” ous knowledge areas. Tools for eViticulture include more than 200 feature articles from basic con- This resource, created by the Grape The mission of the GCoP is to meet cepts of viticulture to the latest, ground- Community of Practice (GCoP) and the educational needs of the grape in- breaking research, written in under- eXtension (extension.org), is directed dustry as a whole; including industry standable language in both English toward commercial viticulturists who partners, extension employees and and Spanish; and an Ask-an-Expert need solid, science-based information consumers by providing science-based feature. to improve their skills in the vineyard. information and learning opportunities through eXtension. Future content will include webinars, “This community of practice is made up videos, online courses and smart of a nationwide group of professionals To learn more about eViticulture con- phone applications. with experience in grape production,” tact Eric Stafne at: eric.t.stafne@ok- said Stafne. “All states involved have a state.edu, follow on Twitter @eviticul- “Any professional in the field of viticul- grape industry, from very large to very ture or online at eviticulture.org. ture, hobbyist or consumer will be able small, and all have an increasing inter- to access information about any aspect est in grape production.” of growing and producing grapes,” said Eric Stafne, Oklahoma State University Expertise within the GCoP Cooperative Extension viticulture spe- includes integrated pest cialist. management, plant pathology, food science, dis- “This project endeavors not to dupli- tance education, variety cate information in other university selection, canopy man- websites, but to work synergistically agement and rootstocks, Year in Review cont. from page 2 As an added caution, continuous appli- mechanical injury, or from contami- cation of pesticides below labeled rates nation in nursery propagation beds. can lead to resistance development, This is why obtaining cuttings from especially if those products are consid- certified, reputable nurseries is of ered “high risk”, and you are applying the utmost importance. them successively. Remember to ro- tate fungicides with those of a different Due to the extensive winter dam- chemical class (called FRAC codes). age in the state, it is no surprise that we are seeing high numbers Poor control of canopy mildew the pre- of symptomatic vineyards. Vines vious growing season, particularly after that are infected will not only have véraison, allows the fungus to build a visible galls (either milky white, to reservoir of inoculum for the following light brown, to black, depending on year. This sets the stage for a high-risk age), but will likely have a yellow- year the next season. Post-harvest dis- ing, stunted canopy, and fruit will be ease management in years with condu- desiccated. Entire cordons or vines cive weather conditions is a must. will display symptoms. The galls are perennial. Crown Gall Unfortunately, there is nothing that Figure 3. A common side effect of winter freeze damage is the development of crown gall. Galls Reports of extensive crown gall out- can be done economically to con- seen here developed over a 6-week period in the breaks in vineyards have also been trol crown gall on a whole-block Yakima Valley. rolling in since early-mid August. Crown scale. Retraining to below the gall gall is caused by the bacterium Agro- in individual vines is often done. Conclusion bacterium vitis, and the symptoms are However, if suckers were not retained characteristic plant “tumors”, or galls this season, cutting back is not recom- What a vintage it has been! With vérai- (Fig. 3). The galls eventually girdle the mended until normal dormant pruning. son closing in, and summer tempera- plant and cause vine collapse. If an extensive outbreak is seen in an tures finally arriving, we are reminded individual block, replanting is an option, that Washington is still the perfect cli- The bacterium can infect plants directly but remember that the bacterium can mate for wine. But it is clear that Mother via causing lesions on roots, or through survive in/on root debris and in the soil, Nature likes to assert her authority ev- open wounds. Infections are often as- and fumigation to reduce the bacterial ery now and again. This was definitely sociated with winter or other forms of population may be necessary. her year.

13 Personnel Announcement in V&E

Fulbright Scholar Tenure and Promotion Book Recognition Biljana Petrova Naidu Rayapti Markus Keller

Biljana Petrova is Congratulations Dr. Markus Keller was a new Ph.D. stu- to Dr. Naidu Ray- recently awarded the dent in located at apti at WSU- best viticulture book WSU-Pullman. Prosser for re- of the year from the Petrova is a winner ceiving his tenure Organisation Interna- of the International promotion this tionale de la Vigne et Fulbright Science summer. du Vin (OIV), for his and Technology book “The Science of Award and will be Rayapati is now Grapevines: Anatomy working with Dr. an associate pro- and Physiology.” Charlie Edwards. fessor in Plant She attended Sts Pathology, and Selling over 1,300 copies in its first year Cyril and Methodius University in Sko- has been working on the identifcation alone, “The Science of Grapevines” is pje, Macedonia and earned a B.S. De- and management of grapevine viral quickly becoming a staple viticulture gree in Plant Protection and M.S. in diseases, particularily those associated reference. It is an excellent synthesis Technological Microbiology. As part with grapevine leaf roll virus complex. of the scientific literature as it relates of her M.S. degree, Petrova studied His work, as demonstrated in this issue to grapevine physiology. Dr. Keller will indigenous yeast microflora on Semil- of VEEN, has had tremendous impact be recognized at a reception in Paris in lon grapes grown in the Kumanovo re- on the WA wine industry. December. gion. At WSU, she is investigating control methods for Brettanomyces. Upon Many of his extensive efforts, and re- “The Science of Grapevines: Anatomy graduation, Petrova hopes to return to search program, can be seen at: http:// and Physiology” is available for pur- Macedonia to continue studying wine wine.wsu.edu/research-extension/ chase from www.Amazon.com and microbiology (yeasts) as well as teach grape-growing/plant-health/virology/ other bookselling retailors. at the university. Welcome to WSU!

Calendar of Events

Date Description

2 Sept 2011 Fieldman’s Breakfast, Prosser, WA 7 Sept 2011 Gearing up for Harvest Wkshp,WSU-TriCities 6 Oct 2011 Fieldman’s Breakfast, Prosser, WA 3 Nov 2011 Fieldman’s Breakfast, Prosser, WA 1 Dec 2011 Fieldman’s Breakfast, Prosser, WA 5 Jan 2012 Fieldman’s Breakfast, Prosser, WA 15-28 Jan 2012 WSU Int’l Winery and Vineyard Tour, Chile & Argentina 2 Feb 2012 Fieldman’s Breakfast, Prosser, WA 7-10 Feb 2012 WAWGG Annual Meeting, TriCities, WA 21-22 Feb 2012 Grape Pest Management Wkshp, Prosser, WA Check the website for changes and updates to the Calendar of Events. The next VEEN will be in March/April and is accepting events between April 2012-Sept 2012 Let Jim ([email protected]) or Michelle ([email protected]) www.wine.wsu.edu know of your events by 15 March 2012.