Black Rot

Black rot is caused by the fungus Guignardia bidwellii and is a very serious grape disease in Connecticut. We had a run in with black rot during the 2013 growing season in our newly planted vineyard. Guignardia bidwellii primarily overwinters in mummified berries on the soil surface or in old clusters still attached to the vine. Ascospores (the sexual overwintering spores), require free water and temperatures of 50 to 90°F (80°F is optimal, germination time is 6 hrs) to germinate. All new growth is susceptible to attack during the growing season including young leaf laminae, petioles, shoots, tendrils and peduncles. A single ascospore infection can result in the development of millions of secondary conidia in the vineyard.
A Cornell Cooperative Extension Disease Identification Sheet No. 102GFSG-D4 published in 2003 by Wayne Wilcox is very helpful. I found the lifecyle of the fungus in that online publication.:¹

Good sanitation practices in the vineyard can reduce the black rot inoculum. These practices include:

• Remove all mummies during the dormant pruning process
• Cultivate beneath the vines near budbreak to bury any mummies
• Improve control by canopy management practices that promote air circulation for drying of the leaves and fruit

For much more information, the first reference below, is the link to the publication written by Wayne Wilcox. It contains pictures of grape leaves, fruit and stems infected by black rot and is an excellent reference

References:
1. Wayne Wilcox, Black Rot, Cornell Cooperative Extension.
2. Roger C Pearson and Austin C. Goheen, Compendium of Grape Diseases, APS Press, Published by the American Phytopathological Society, 3340 Pilot Knob Rd., St. Paul, MN 55121.
3. Virginia Tech Online Guide To GRAPEVINE DISEASES.
4. Mizuho Nita and Mike Ellis, Integrated Management of Grape Diseases, Ohio State University, Department of Plant Pathology.

2011 Failla Pinot Noir Sonoma Coast

We had this 2011 Failla Pinot Noir Sonoma Coast with roast elk, potatoes and shiitake mushrooms. We purchased this bottle of Failla from the same place that we were able to find the 2008 Brewer Clifton Pinot Noir. What a lucky day that was!
We first heard about Failla wines and winemaker Ehren Jordan from Greg and Linda Pearl of Pearlessence Vineyards. The wine was clear and burgundy in color and reminded me of the cool climate Pinot noirs of Prince Edward County. To me, it tasted like sour cherries that are baked in a pie with good acidity and was the perfect compliment to our dinner.

Downy Mildew

I'm still in my self education mode regarding the fungi that can infect our vines. Earlier, I blogged about powdery mildew in Strategies to Control Powdery Mildew: Part I and followed up with Strategies to Control Powdery Mildew: Part 2. I'm also collecting the blogs that deal with fungal diseases under the tab Fungal Diseases of Grapevines.
Next fungal disease: downy mildew. Downy mildew in grapes is caused by the fungus Plasmopara viticola, an oomycete in the order Peronosporales. Spring and summer rainfall at temperatures above 50ºF releases the oospores which is the primary inoculum. The oospores form a single germ tube terminating in a sporangium that constitutes the means of secondary spread of the pathogen, when they produce zoospores. The zoospore is a small swimming spore that needs water for dissemination and grape leaf stomata for entry and penetration into the inner tissues of the vine.
These zoospores initiate secondary infections which can occur in as little as two hours of wetting at 77°F or up to 9 hours at 43°F. Infections are usually visible as lesions in about 7 to 12 days, depending on temperature and humidity.
I found a very well annotated life cycle of downy mildew at The Ohio State site. The site credits the New York State Agriculture Experiment Station. Figure taken from Grape IPM Disease Identification Sheet No. 1.

Symptoms on leaves are small yellow lesions also known as oil spots. Young berries are also highly susceptible to downy mildew. They appear grayish when infected causing gray rot and become covered with a downy felt of fungus sporulation. Berries become less susceptible as they mature, but rachis infections can spread into older berries causing brown rot, having no fungus sporulation.
More information can be found in the references listed below.

References:
1. APSnet Downy Mildew of Grapes.
2. Downy Mildew Plasmopara viticola Michigan State University AgBioResearch.
3. UC Davis IPM Online Grape Downy Mildew.

Skyping with Rodney Strong Winemaker Justin Seidenfeld at The Wine Store

Last night, we went to The Wine Store in Westerly to be part of Skyping with Justin Seidenfeld, the winemaker at Rodney Strong. The idea behind the Skyping was to taste 4 different Rodney Strong wines, the 2012 Charlotte's Home Sauvignon blanc, the 2012 Chalk Hill Chardonnay, the 2010 Knotty Vines Zinfandel and the 2010 Symmetry Meritage while Justin explained how the wines were made. Justin began the tasting with an explanation and the location of the vineyards that Rodney Strong wines are made from, since only great grapes make great wines.
I asked the question about the impact of the California drought on the vines, but Justin wasn't too concerned since their water is derived from well water. What their water is mostly used for is to protect the vines during bud break if a frost event occurs. The vines are sprayed with water which freezes, causing an exothermic reaction that releases heat, thereby protecting the young growth. Justin explained that they are in the middle of changing over from water to wind in order to become sustainable and green during these spring frost events. James Morrison poured the first wine which was the 2012 Charlotte's Home Sauvignon blanc and Justin explained that the wine was made in oak with batonnage. The vineyard is named after Rodney Strong's wife Charlotte. The next wine we tasted was the 2012 Chalk Hill Chardonnay. The wine is made in new French oak, again with batonnage. Justin also mentioned that when he went to Domaine Leflaive he learned that they put the finished wine in stainless steel tanks on it's lees until it is bottled. I could taste the oak in the Chardonnay, but it was very well integrated. We next had the Zinfandel and finished the tasting with the 2010 Symmetry

Meritage which Justin explained was a blend of the 5 Bordeaux grapes, Cabernet sauvignon, Cabernet franc, Merlot, Petit verdot and Malbec. We were able to ask Justin many more questions and he entertained us with stories about Rodney Strong. Justin is able to experiment with various grapes and is developing his own cuveé! He also explained how the weather conditions affected the ripening of the different varietals which leads to the differences in the various vintages. Justin explained that they also do tastings of other maker's wines in order to compare how their wines taste alongside their peers as well as how they compare with aspirational wines. It was an educational and entertaining evening. Kudos to James and Shannon for hosting such a good time!

2008 Brewer Clifton Pinot Noir

Recently, we had this 2008 Brewer Clifton Santa Rosa Hills Pinot noir with our dinner of panko crusted chicken. We purchased this bottle from one of our favorite package stores in Massachusetts when we went to make our champagne run. We were surprised to see a Brewer Clifton in our neck of the woods and thought we would give it a try. The wine was a clear, dark purple in color and had a bouquet of dark cherries and a little bit of leather. It was such an approachable fruit forward wine without being over the top. So for around $30.00 this is a great value for a Pinot noir.

Strategies to Control Powdery Mildew: Part 2

This blog is Part 2 of two blogs written on Strategies to Control Powdery Mildew: Part 1, largely extracted from an article written by Wayne Wilcox in the March, April 2003 issue of Practical Winery and Vineyard Journal called Strategies to Control Powdery Mildew.¹
Compounds used to control powdery mildew can be classified into the following groups as illustrated in this figure from the Dow AgroSciences website, and the PDF Managing Powdery Mildew in Grapes (CA).²

The above figure contains an acronym, FRAC which stands for Fungicide Resistance Action Committee and the following link provides information regarding FRAC Code List ©*2013: Fungicides sorted by mode of action (including FRAC Code numbering.) The following table is a summary of the chemicals available to control powdery mildew:^1,3

FRAC CODE	Pros	Cons
M i.e.Sulfur	Generally considered as a low risk group without any signs of resistance developing to the fungicides Cheap and effective Is a contact fungicide Protects existing foliage	Acts largely through the vapor phase and is temperature sensitive Inactive below 65 oF Phytotoxic at temperatures above 85 oF
3 i.e.DMI (DeMethylation Inhibitors)	Provides significant post infection activity PROTECTIVE and CURATIVE activity on powdery mildew	Declining efficacy due to increased resistance
11 i.e.Qols (Quinone outside Inhibitors)	Excellent protectant fungicides Best when present on the foliage or fruit before a spore lands and tries to infect Show significant “anti-sporulant” activity Provides some post-infection control against PM	Possibly more dangerous in terms of future resistance development High risk
13 i.e. aza-napthalene; Quintec is the only member of this class	Ability to redistribute across expanding leaf and berry tissues after application Can protect parts of the leaves and bunches that may not have received direct spray coverage Can protect grapes from powdery mildew for up to 21 days	Resistance to quinoxyfen known Medium risk
NC i.e. biologicals	Uniquely susceptible to topical applications of numerous alternative products (oils, potassium salts, hydrogen peroxide)	Appear to act primarily as temporary eradicants, with little or no protective activity against new infections Resistance not known

This is a lot to process and I'll be looking at more online information to get a better understanding of all of the available powdery mildew control agents, how to use them and what is the best chemical(s) to use for a vineyard trying to be organic.

References:
1. Wayne Wilcox, Strategies to Control Powdery Mildew, Practical Winery and Vineyard Journal, March, April 2003.
2. Managing Powdery Mildew in Grapes (CA).
3. FRAC Code List ©*2013: Fungicides sorted by mode of action (including FRAC Code numbering.)

Strategies to Control Powdery Mildew: Part I

These days finds us trying to familiarize ourselves with the strategies available to control the mildews that we will surely encounter once the growing season is upon us. We have already had our encounter with powdery mildew (PM) last growing season and I blogged about it in Erysiphe necator: Powdery Mildew, which shows what infected grapevines look like. I found an article online written by Wayne Wilcox in the March, April 2003 issue of Practical Winery and Vineyard Journal called Strategies to Control Powdery Mildew and read it with interest. Wilcox writes that although cleistothecia do require at least a brief rain to release their ascospores, neither these spores nor the conidia require moisture in order to germinate and cause infection. The primary factors that control the spread of PM are temperature and relative humidity. The part of the PM lifecycle that becomes relevant in the spring is shown by the red circle in the figure below:

The ascospores from the overwintering chleistothecia (chasmothecia), can be released with as little as 0.1 inch of rain when temperatures are 50 ^oF. The released ascospores are the primary infection which develop into lesions that produce another kind of spore called the conidia. The conidia forms the powdery or dusty appearance that is visible to the eye and is the cause of the secondary infection that can result in the exponential growth of the disease through the vineyard when the temperature is in the ideal range between 68-77 ^oF.

Crop Susceptibility:
• Leaves are highly susceptible to infection while they are expanding, but become resistant soon after they’re fully expanded
• Berries are highly susceptible from bloom until shortly after fruit set, but become much more resistant afterwards

Since powdery mildew is a disease of young, juvenile tissues, sprays applied from the start of bloom through bunch closure are responsible for the lion’s share of PM control on the berries.
Temperatures above 90 ^oF as well as rain or condensation on the leaves and fruit are detrimental to disease development.
Stay tuned for the next blog, Strategies to Control Powdery Mildew: Part 2 for what kinds of steps can be taken to control powdery mildew.

References:
1. Wayne Wilcox, Strategies to Control Powdery Mildew, Practical Winery and Vineyard Journal, March, April 2003.
2. The illustration is from the Compendium of Grape Diseases, 1988, American Phytopathological Society, St. Paul, MN. USA, pg. 10.

Champagne and Oysters, Oysters and ...

It began with an enjoyment of having champagne and oysters on New Year's Eve and has evolved into a monthly gathering of our friends where we open up our kitchen for what we call "experimental kitchen" in order to come up with the perfect pairing for champagne. Last month we had a Duval Leroy with oysters. It was a brut, primarily made from Pinot noir. The Duval Leroy was less than $30.00, so we thought it was a great value.

We experienced the flipside of this pairing when we went to Hawaii and had sushi at Tokkuri-Tei. Our host and server, Kazu was very personable. We had 5 pieces of sushi each, including one made from raw oysters. So, what to pair with this delectable morsel? We had three kinds of sake. We started with Otokoyama, then went on to Hakkaisan, and finished up with Hakurosuishu. Sake is the right pairing with sushi for sure and it went very well with the oyster sushi. Delish! The dilemma is how to reproduce this at home.
They have an extensive sake menu. The photo below is blurry, we might have to go back to get a better photo while we have another round of sake and sushi:

2005 Bonaccorsi Syrah Star Lane Vineyard

My husband knows the story of Bonaccorsi, about Michael Bonaccorsi and his wife Jenne Lee Bonaccorsi. Michael, a talented winemaker suddenly passed away in 2004. Jenne Lee continues producing limited quantities of Pinot Noir, Chardonnay and Syrah. So, we were very excited when we found this bottle of 2005 Bonaccorsi Syrah, Star Lane Vineyards. We could tell that the bottle had been laid carefully on it's side due to the sedimentation, it is nearly 9 years old, after all. The wine was dark purple in the glass and with 15.9% alcohol, a wine with much higher alcohol that we typically drink. Truth be told, we aren't really fans of high alcohol wines because of the day after effect. This syrah was very fruity and spicey, not the cigar-box type, and brought back memories of having a Saxum syrah.

Cold Hardiness of Grapevines Through Cold Acclimation

We have to look back to last year in order to understand how our grapevines are handling the winter cold. Vines gain cold hardiness as a result of decreasing temperatures. The colder the temperature, the more hardiness the grapevine gains up to a critical threshold that is determined by the following¹:

• Environment
• Cultural practices
• Genetic makeup of the cultivar

Grapevines begin their process of cold acclimation or the transition of the vine from a cold-tender to a cold-hardy state beginning in late summer. The following processes are already complete shortly after leaffall:

• Periderm formation
• Mobilization of carbohydrate reserves to canes, trunks and roots
• Isolation of dormant buds from the vascular tissues in canes and trunks

There are two basic stages of cold acclimation in grapevines that occurs before the onset of winter:

• First stage: induced primarily by low but above freezing temperatures (above 32 ^oF) and occurs in late summer to early fall before any freeze events
• Second stage: exclusively induced by temperatures below freezing and usually coincides with the first killing fall freeze in mid-October to mid-November

One question was answered for us on page 21 of the Michigan State University publication regarding windchill: Because dormant grapevines neither generate internal heat nor significantly evaporate water, windchill does not alter the temperature experienced by the bud. Reading about the processes of cold acclimation is somewhat reassuring but we still have to do the test for bud injury in order to access how the vines faired.
References:
1. Tom Zabadal, Winter Injury to Grapevines and Methods of Protection, Michigan State University, Extension Bulletin E2930, June 2007, pg. 7.

How to Test for Bud Injury

The winter weather this year has been anything but "normal". The polar vortex that dipped into Connecticut on January 8-10 bringing subzero (^oF) temperatures was followed by a deluge of rain on January 11 and then the January thaw on the 13th-17th, brought temperatures in the mid-40's. These temperature swings can cause confusion in the vine where warming trends might signal the vine to begin the process of deacclimation.
There is a test that can be done in the vineyard to see if dormant buds have suffered winter injury. There is a lot of information on line regarding how the test should be done, but I found the photos from the Michigan State University publication Winter Injury to Grapevines and Methods of Protection by Tom Zabadal to be very helpful. They show how to evaluate the dormant buds by making the appropriate slices. The annotations A-F in the bottom photo, Figure 1, correspond to the cross-section series in the Table 1 below.¹
Figure 1

Table 1

	Photo A to the left shows the bud scales of the central primary bud.
	Photo B to the left shows the bud scales of the primary, secondary and tertiary bud scales.
	Photo C to the left shows the green tip of the primary bud which is the indication that this bud is alive. This is what you want to see when you take slices through the bud. Further cut into the bud corroborate if the rest of the bud has survived but winter cold.
	Photo D on the left shows that a deeper cut made into the bud reveals the primary bud and more of the scales of the secondary and tertiary buds.
	Photo E corresponds to the slice taken from the top photo and shows the tips of the primary, secondary and tertiary buds. The green color is a good indication that all three of the buds are alive.
	Photo F shows the green tissue at the base of the compound bud that connects it to the cane.

There are also two YouTube Videos made by Hans Walter-Peterson of the Cornell Cooperative Extension on how to do field testing for bud injury prior to pruning. Here are the links:
Bud Injury Testing Part 1
Bud Injury Testing Part 2

References:
1. Tom Zabadal, Winter Injury to Grapevines and Methods of Protection, Michigan State University, Extension Bulletin E2930, June 2007, pg. 27, 30.