Last Friday I gave a presentation at the Fall Flower & Garden Fest entitled “Growing Bunch Grapes in Mississippi”. This festival is held every year in Crystal Springs, Mississippi at the Mississippi State University Truck Crops Experiment Station. I usually attend and give a talk on some aspect of fruit crops. This year it was bunch grapes. Of course one cannot cover all aspects of growing grapes in a 30 minute block, but the link below will take you to the presentation (as a PDF file). It gives some of the very basics when considering bunch grapes in our climate. So, take a look and if you have any questions feel free to ask!
This year I harvested several different cultivars of grapes for the purpose of seeing what kind of firmness and splitting data I could get. It was not a true study, just a quick “look-see” to get an idea of how it would work. Below is some of the observations I was able to get (will help from Dr. Donna Shaw and Lavonne Stringer). Brix (sugar levels) were recorded first to see how high they were at harvest. Nine cultivars were chosen — Blanc du bois, Champanel, Cimarron, Conquistador, FAMU99, MidSouth, Miss blanc, Victoria Red, and Villard blanc. As you can see below, sugar levels were low for most, although these were only samples and the entire vine was not necessarily harvested.
Individual berries were then tested for firmness, as seen below. In most cases, the lower the brix, the better the firmness. This is not surprising as unripe berries would be expected to be firmer. One big exception was Conquistador which was the firmest berry by far, even at nearly 18 brix.
Finally we looked at how the berries split if exposed to water. We did this in two ways, individual berries and also as whole clusters. The results were almost the same both ways but I will show both. MidSouth, FAMU99, and Conquistador showed a tendency to split when submerged in water overnight. So in this case firmness did not seem to be strongly tied to splitting tendency.
Things were mostly the same when whole clusters were submerged, although there was a little more on Blanc du bois. The difference was small though and with replication and a larger sample size may not be significantly different.
I was surprised by the lack of splitting from Victoria red. It has what I would characterize as a thinner skin than most of these cultivars, yet it did not split at all. A good thing to know. Obviously Conquistador has a tendency to split, as ~50% of exposed berries did just that. Next year we will give it another go-round and see what happens then.
More rain is falling today and is expected for the next few days. All this wet and cooler weather creates good conditions for anthracnose infections. Anthracnose (Elsinoe ampelina) can be severe in years with heavy and consistent rainfall (like this year). Optimal conditions for disease development are in the upper 70s F. The spores are splashed from plant to plant by rain. It is seen most commonly on young, succulent green shoots and leaves. The lesions are sunken on shoots and on leaves the leaves can be distorted and have a shot-hole appearance. A photo of the disease on a ‘Victoria Red’ cluster is below.
How can anthracnose be controlled? If you are in the Deep South, not too easily, I’m afraid. Sanitation can help (get rid of infected plant parts). Canopy management that promotes sunlight penetration and good airflow can also help. But likely the best way is a dormant fungicide spray or two of lime sulfur followed by subsequent fungicide applications until veraison. More in-depth information can be found here:
Thanks to a grant from the Specialty Crops Block grant program and the Mississippi Department of Agriculture and Commerce, MSU Extension Service will be hosting two short courses for grape and muscadine growers. One will be held in Verona and the other in Hattiesburg. Each short course will meet on two dates, one in February and one in July, so that attendees can see and experience the vineyard at different growing seasons. Because the grant covers all the expenses, the short course will be free to attend; however, pre-registration is mandatory. Below the schedules and registration form can be downloaded.
This course is intended for COMMERCIAL growers (and those interested in becoming commercial) only — those who currently grow or wish to grow for markets (farmer’s markets, local retail, wineries, etc.). Please see the links above for further details and feel free to contact me with any questions you may have. We look forward to seeing you at these great events!
Nutrient deficiencies can adversely affect grapevines, not only the growth of the vine itself, but also the fruit. Here in Poplarville, the soil pH is low. To give you an idea, in general this area is good for growing blueberries. Blueberries thrive in soil pH of 4.2-5.2, which is too low for most grapevines. Often in other regions I have seen Iron (Fe) deficiency but here, because of the low soil pH, I am seeing Magnesium (Mg) deficiency show up. The photo below shows what late season leaf symptoms look like. I don’t remember which vine this came from — some cultivars appear to tolerate the soil pH better than others.
So, what to do about it? Raise the soil pH with lime is the first thing. If that doesn’t alleviate the problem, then foliar or soil applied sprays may be necessary. My colleague at Cornell University, Hans Walter-Peterson, gives an excellent primer on Mg deficiency and offers suggestions for correcting it. You can find that here: http://www.growingproduce.com/uncategorized/managing-magnesium-in-grapes/. The eXtension grape community of practice has a good article on other potential disorders too — that article can be accessed here: https://www.extension.org/pages/31599/grapevine-problems:-leaf-spots-not-caused-by-insects-or-disease#.U-jgJfldV8E
You may be inclined to think, “It is after harvest, so I shouldn’t worry about it”. Nutrient deficiencies can lead to poor winter hardiness, overall vine stress, and other issues. It is best to correct the problem rather than to let it negatively affect the vine.
Tomorrow is the Field Day at the Beaumont Horticultural Unit (http://msucares.com/crec/beaumont_office.html). Below is the schedule. As you can see, I will be speaking about bunch grapes. Earlier this year we put out some Villard blanc, Miss blanc, and Blanc du bois. They are looking good so far. Come on out and see for yourself!
Vegetable Field Day
Beaumont Horticultural Unit
June 13, 2013
8:00 Registration and Biscuits
8:45 Overview of the Beaumont Horticultural Unit
Dr. Christine Coker
9:00 Pollinators for Vegetables
Dr. Blair Sampson
9:15 Safe Handling of Produce
Dr. Barakat Mahmoud
Move to Field Station Presentations (15 mins each)
9:40 Management Practices for Small-Scale Vegetable Production
10:00 Southernpeas and Sweet Corn Trials
Dr. David Nagel
10:20 Southern Stem Rot in Peanut
Dr. Alan Henn
10:40 Hops Production in Mississippi
11:00 Bunch Grapes for the South
Dr. Eric Stafne
11:20 Visit Exhibitors; Q&A
Dr. Vasile Cerven – high tunnel construction, technology, and production
Randy Coker – Mississippi MarketMaker
Special Thanks to Mike Ely, Thomas Freeman, and Corey Wheeler.
The title is a little mis-leading as I will be there to talk about some newly planted grapevines (bunch grapes, not muscadines). More info on the Beaumont station is here: http://msucares.com/crec/beaumont_office.html
Hope to see you there.
Introduction to Grapes
Grapes are in the Vitaceae family which consists of 11 genera and 600 species, including the most commercially important genus, Vitis. Vitis is the only food-bearing genus in the family and has two subgenera: Euvitis and Muscadinia. All bunch grapes are in the Euvitis subgenus of which Vitis vinifera is the most important species. V. vinifera originated in the Caspian Sea region and there have been more than 5000 named cultivars. The range in which V. vinifera can be successfully cultivated is limited by climatic factors. This species requires a long growing season, relatively high summer temperatures, low humidity, a rain-free harvest period, and mild winter temperatures. It is most often used for wine, but these grapes can also be used to produce juice, raisins, canned good, rootstocks, or for fresh consumption.
Other Important Grape Species
There are also other important grape species that have been utilized in the creation of interspecific hybrids. These species are from North America, and the most well-known is V. labrusca. V. labrusca (also called V. labruscana) is commonly called the Fox Grape. The most famous cultivars from this species are ‘Concord’, ‘Niagara’, and ‘Isabella’. It has large berries, small clusters, fair pest resistance, and a distinctive and strong flavor. The Riverbank Grape is V. riparia. Several cultivars have this species in their lineage, such as ‘Beta’, ‘Clinton’, ‘Baco Noir’, ‘Marechal Foch’, and rootstocks 3309C, 5BBK, and SO4. It has small berries and small clusters with wide variation in ripening time and cold hardiness levels. It is vigorous, roots easily (which makes it attractive to use as a rootstock), and has fair to good pest resistance. The Summer Grape is V. aestivalis, which is mainly known for the cultivar Cynthiana (also called Norton). It has small to medium berries with medium to large, open clusters, and fair pest resistance. One of the issues with this grape is its tendency toward high sugar and high acid, thus rendering wine-making a challenge. V. rupestris is commonly known as the Sand Grape. Cultivars using this species are ‘St. George’ and the rootstock AxR1. It has small berries, small to medium clusters, and has a very “wild” taste. The plant is vigorous and roots easily while having good pest resistance. Another important species is V. lincecumii, the Post Oak Grape. This species is native to the southern plains states. Many cultivars have this species in their background, including ‘Bailey’, ‘Beacon’, ‘Ellen Scott’, ‘Marguerite’, and ‘Rubaiyat’. It has medium to large berries with small to medium clusters and a distinctive “wild” taste, but different from V. labrusca. It also has fair pest resistance. This species was hailed by T.V. Munson as being especially important for creating hybrid grape cultivars.
Hybrid Grape Origins
The creation of interspecific hybrid grapes primarily came about because of problems encountered in France in the 1860s. A devastating phylloxera outbreak began there in 1860 and in the next 20 years about 90% of French vineyards were destroyed. To combat this epidemic, cultivars derived from American species were planted. At one time over 25,000 acres of ‘Noah’ was planted in France. ‘Clinton’, ‘Othello’, ‘Lenoir’, ‘Isabella’, and ‘Herbemont’ were also planted. ‘Concord’, ‘Catawba’, and ‘Delaware’ were tried but had low resistance to phylloxera. These species also brought with them new disease problems like downy mildew and black rot. In 1876, it was found that V. vinifera cultivars could be grafted onto American grapes successfully. The discovery helped transition back to V. vinifera grapes, but diseases were also a problem. In 1885, Bordeaux mixture was discovered as a broad spectrum fungicide to help alleviate the disease problems.
French hyrids originally started as breeding for rootstocks on which to place V. vinifera grapes. Amateur grape breeders pushed the breeding process forward to look for vines with roots resistant to phylloxera, foliage resistant to fungal pathogens, and fruit that could produce wines more similar to V. vinifera types. The first stage of breeding for hybrids used crosses of American cultivars or rootstock with V. vinifera cultivars. This stage of breeding produced some cultivars such as ‘Baco noir’ and ‘Baco blanc’. Some of the important American types used in the breeding process were ‘Noah’ and Jaeger 70. The V. vinifera cultivars used included ‘Folle Blanche’, ‘Aramon’, ‘Clairette’, and ‘Cinsaut’. The second wave of breeding for interspecific hybrids used crosses between hybrids gained from the first stage. Some of the influential breeders of this time period were Seibel, Bertille Seyve, Joanes Seyve, Galibert, and Landot. The third stage of hybrid breeding led to the modern hybrid grapes commonly grown today. These were usually crosses of hybrids from the second stage with V. vinifera grapes to gain superior wine quality. However, with the elevation of wine quality came the dilution of pest resistance. There are several breeding programs now involved around the world in creating high quality hybrid grapes. Some of the programs in the United States are in New York, Arkansas, California, Florida, Mississippi, Georgia, North Carolina, and Missouri.
Commercial Hybrid Grapes
There are many high quality hybrid grape cultivars available. Some examples follow:
‘Chambourcin’ (true parentage unknown), high yielding, moderately cold hardy, vigorous, disease resistant, also grown in France and Australia.
‘Chardonel’ (Seyval Blanc x Chardonnay), highly productive, moderately cold hardy, makes a wine very similar to ‘Chardonnay’, patented.
‘Frontenac’ (V. riparia x Landot 4511), vigorous and productive, very cold hardy, very resistant to diseases, must limit skin exposure in wine making, needs malolactic fermentation.
‘Marechal Foch’ (includes V. riparia, V. rupestris, and V. vinifera), a sibling of ‘Leon Millot’, vigorous, early ripening, good winter hardiness, early budbreak, fruitful secondary buds.
‘Traminette’ (J.S. 23.416 x Gewurztraminer), similar wine character to ‘Gewurztraminer’, good disease resistance, decent winter hardiness, large clusters, good yields.
‘Vignoles’ (unknown), cold hardy, moderate vigor and productivity, compact clusters, susceptible to bunch rots, makes a fruity, sweet wine.
Hybrid grapes make good substitutes in areas where V. vinifera grapes are marginally adapted or not adapted. The modern hybrid grapes produce high quality wines that do not include “off” flavors that are characteristic of some older hybrids. Rombough (2002) stated that hybrid grapes can be as successful as V. vinifera grapes. He wrote:
“The question is one of marketing, and nothing else. Most wineries make their money from the walk-in trade. And each and every walker-in is amenable to hand-selling…it doesn’t matter what name is on the label, so long as there is quality in the bottle.”
Quality is an important aspect to consider. Adaptation is very important when deciding what type of grapes to grow. Just because V. vinifera cultivars like ‘Pinot noir’ or ‘Zinfandel’ make exceptional wines elsewhere does not necessarily mean they will make good wines everywhere.
Einsett, J. and C. Pratt. 1975. Grapes. p. 130-153. In: (J. Janick and J.N. Moore, eds.), Advances in fruit breeding. PurdueUniv. Press, West Lafayette, Ind.
Rombough, L. 2002. The grape grower: a guide to organic viticulture. Chelsea Green Publishing. White River Junction, Vermont.
Snyder, E. 1937. Grape development and improvement. Yearbook of Agriculture 1937. US Dept. Agriculture. p. 631-664.
[Originally published: Stafne, E.T. 2008. Origins of interspecific hybrid winegrapes. Proc. 27th Annu. Ark. Okla. Hort Indust. Show 94-96.]
The muscadine vines are now flowering. Some muscadines vines are dioecious, meaning they have only male or female flowers. However, many of the common cultivars have perfect flowers (both male and female parts — also termed hermaphroditic). In the first photo below, we see that the flower cluster is in various morphological stages.
The next photo shows an inflorescence that is in the last stages of anthesis. In fact, some of the flowers have been fertilized and the beginnings of berries can be seen. The pistil (female flower part) and stamens (male flower part) can both been seen clearly as well.
Unlike Euvitis bunch grapes, both wind and insects play a role in the pollination process. The resulting fruit will be a loose cluster in which the berries abscise and fall to the ground when ripe. I will continue to follow the fruit morphology throughout the season and post it here.
Is there potential for a winegrape industry in the Gulf Coast Region using interspecific hybrid bunch grapes? Texas is trying to figure that out. Fritz Westover, Viticulture Specialist with the Texas AgriLife Extension Service (Texas A&M) has written some nice articles describing two of the most promising varieties — Blanc du Bois and Lenoir (also known as Black Spanish). Blanc du Bois is a white grape and Lenoir is a red grape. Both are tolerant of Pierce’s Disease, the major limiting factor in growing grapes in this region. We have some Blanc du Bois in Stone County. I noticed that this Spring it had some issues with Anthracnose (a fungal disease), but that can be controlled with fungicides (we are observing the vines so we are not spraying them at this time). We have a few other varieties in the ground (some doing better than others) and plan to put some more in — including Blanc du Bois and Lenoir.