Education and Experimentation via Mississippi Bunch Grapes

And when I say “grape harvest” I mean bunch grapes, not muscadines (which will come later in the season).  This year the vines in my vineyard were in the 3rd leaf.  I harvested a little fruit last year, but this year was the first “big” harvest. Since most of the harvested vines were part of a study, I did various measurements on them (total weight, cluster and berry weights, brix, TA, pH), but had a conundrum — what do I do with the fruit?  The majority of the harvested grapes was from three cultivars: Blanc du bois, Miss blanc, and Villard blanc.  I also harvested a little from MidSouth.  In the end I gave it all away, some of it to folks who helped harvest, but also some to help a business do some experimentation of their own.

Mark and Travis from Lazy Magnolia Brewing Company helping harvest a few vines of Miss blanc

Mark and Travis from Lazy Magnolia Brewing Company helping harvest a few vines of Miss blanc.

Lazy Magnolia Brewing Company is located in Kiln, Mississippi.  Just after I moved here in 2011, my wife and I went for a visit to the brewery where we met Mark Henderson, co-owner. We asked questions about the brewery biz and he asked what we did for a living.  After telling him I worked with grapes, he became very interested and said he wanted to source some local grape juice for a project.  I told him, “good luck” because there was none to be had.  Later, I connected with a local grower, Dr. Wayne Adams, who had some fruit but not enough to supply Mark.  I planted the grape vines as a response to his request. After moving here, I thought my days with grapes was probably over, but what I have found out is there there is a strong interest in Mississippi just like everywhere else. In 2014 I wrote a Specialty Crops Block Grant funded through the Mississippi Department of Agriculture and USDA-NIFA that focused on grape education.  This vineyard helps to bolster that education component.

Fast forward to 2015 and I have vines producing fruit.  I again contacted Mark and asked if he wanted the juice to do some experimenting on.  He said yes.  Unfortunately the Blanc du bois was not in good shape.  It had a good bit of rot caused by early season anthracnose then bunch rots.  The very rainy month of May did it no favors.  However, Miss blanc and Villard blanc were in relatively good shape.

Harvested Miss blanc fruit ready for data measurements

Harvested Miss blanc fruit ready for data measurements.

After getting the fruit in from the field, we took some data measurements then pressed it for juice.  Mark and Travis from Lazy Magnolia came up to help with that process along with my collaborator Dr. Donna Shaw from USDA-ARS in Poplarville.

Dr. Shaw (left) and Mark Henderson (right) pressing Miss blanc grapes for juice

Dr. Shaw (left) and Mark Henderson (right) pressing Miss blanc grapes for juice.

It is a very messy job, but being able to taste the fresh juice is rewarding. Of course it happened to be on one of the hottest days of the year, but then again it is July in South Mississippi!  We were able to get about 20 gallons of juice from 18 Miss blanc vines.  A couple of days later we were able to get 10 gallons of juice from 17 Villard blanc vines.  I also gave Mark about 2 gallons of MidSouth juice (which is acidic but has an intriguing “raspberry” flavor).  So he has between 25-30 gallons to try something (wine, mead, beer, or something else entirely). This project is a beginning to see how Mississippi-grown grapes can be used for marketable products.

If you, or someone you know, is interested in growing bunch grapes in Mississippi please contact me.  Although it is not easy to do, it can be done with the right cultivars and management practices.  Developing markets is another important step in the process, and Lazy Magnolia is exploring whether or not grapes can make a marketable product for their business model with the help of Mississippi State University Extension Service.

Crow Away!

I want to start off upfront with a few things: First, I am not an expert on crow behavior, Second I am a fan of The Black Crowes, Counting Crows, and A Murder of Crows, and Third, I know crows can be a nuisance.

I’m not sure what programs exist in Mississippi to control these bird pests.  I know the Department of Wildlife Conservation in Oklahoma had a program for control, but I am not sure if Mississippi has anything similar. In Oklahoma crows are a significant pest of pecans.

I found a couple links with information on controlling them in Mississippi and it looks like they can be killed if needed to protect crops.

http://icwdm.org/handbook/birds/AmericanCrows.asp

“Crows are protected by the Migratory Bird Treaty Act, a federal act resulting from a formal treaty signed by the United States, Canada, and Mexico. However, under this act, crows may be controlled without a federal permit when found “committing or about to commit depredations upon ornamental or shade trees, agricultural crops, livestock, or wildlife, or when concentrated in such numbers and manner to constitute a health hazard or other nuisance.”

States may require permits to control crows and may regulate the method of take. Federal guidelines permit states to establish hunting seasons for crows. During these seasons, crows may be hunted according to the regulations established in each state. Regulations or interpretation of depredation rules may vary among states, and state or local laws may prohibit certain control techniques such as shooting or trapping. Check with local wildlife officials if there is any doubt regarding legality of control methods.”

https://www.animallaw.info/statute/ms-hunting-%C2%A7-49-1-39-killing-animals-or-birds-injurious-agriculture-exception-migratory

“Statute Text

  • 49-1-39. Killing animals or birds injurious to agriculture; exception as to migratory birds

The commission may issue permits to kill any species of animals or native, nonmigratory birds which may become injurious to agricultural or other interests in any particular community. All migratory birds, including hawks, owls, and eagles and their nests and eggs are protected by the Migratory Bird Treaty Act and federal regulations promulgated under this act. All species of blackbirds, cowbirds, starlings, crows, grackles, and English sparrows may be killed without a permit when such birds are committing or about to commit depredations on shade or ornamental trees or agricultural crops.”

Now, eliminating (killing) crows is not always necessary.  Often exclusion is the best option if possible.  Scare tactics or repellents can also work, but usually only for a limited time period as the crows become wise to it.

My suggestion, if elimination is necessary, would be to contact the US Fish and Wildlife folks in Jackson for more info: http://www.fws.gov/jacksonwildlife/.  Also available is The Center for Resolving Human-Wildlife Conflicts at Mississippi State University which can be found at this website: http://www.humanwildlifeconflicts.msstate.edu/#&panel1-1

A Few Early Grape Clusters

This morning I was out in the vineyard to harvest a few grape clusters for a study on Spotted Wing Drosophila (SWD) egg laying habits conducted by Dr. Blair Sampson.  These cultivars are unusual in that they are rarely grown outside of the southern U.S.  I harvested one or two clusters (depending on the number of berries available per cluster) from ‘Victoria Red’ (Ark 1123 x Exotic), ‘Cimarron’ (V. cinerea var. canescens x Seneca), ‘MidSouth’ (De Grasset x Galibert 255-5), ‘FAMU 99′ (unknown to me), and ‘Champanel’ (V. champinii x Worden).  These are not fully ripe in the eating or processing sense, but they are close enough for this study to work.  Below is a photo of ‘Champanel’, ‘Cimarron’, and ‘MidSouth’.

Champanel, MidSouth, and Cimarron (Top to Bottom)

Champanel, MidSouth, and Cimarron (Top to Bottom)

So, even though I have these in my vineyard it doesn’t mean they do well.  This is the first year I’ve had Champanel grapes, but overall it looks decent.  The vine looks healthy, not a lot of rot (which is really saying something this year), no PD symptoms, and a good bit of fruit.  I had trouble establishing the vine for whatever reason, but it looks good now.

MidSouth is an intriguing vine that I have written about before.  It has a moderate vigor and moderate yield.  The vine is suffering from a nutrient deficiency (that I believe is Mg) that some vines in the vineyard show symptoms of as well.  However, overall the vine looks okay.  The flavor is what I like — it reminds me of raspberry.  It isn’t quite ripe yet though and acid levels are high.  It was never recommended as a wine grape although it could be useful in blending (maybe).

Cimarron is a cultivar released from Oklahoma State University in the 1970s.  A strong Concord-like flavor and aroma.  It does not do well in south Mississippi.  Vines have PD symptoms and have only produced a small amount of fruit.  Terminal portions of the cordons are dying back now and some clusters along with it (from PD).  I suspect they may die back to the ground over the winter and come back, but it is no way to get a viable amount of grapes.  Too bad too, as the clusters don’t have any rot and they look nice.  Other OSU cultivars, Rubaiyat and Sunset are also in the vineyard but have little to no fruit and exhibit PD symptoms.  They are non-starters too.

In the coming weeks I will be harvesting more fruit — even hope to crush some of the Blanc du bois, Miss blanc, and Villard blanc (and perhaps a couple others).

Mississippi Vaccinium Journal for July-Aug 2015

The latest edition of the Mississippi Vaccinium Journal is now available. In this issue topics include a new survey on mechanical harvest, fruit splitting, careful use of herbicides, insecticides and rain, an upcoming GAP/GHP workshop opportunity, a few photos of the Blueberry Jubilee, and Road Trip! MS blueberries go to India.

Download the newsletter here in PDF format: Mississippi Vaccinium Journal volume 4 issue 3

As always you can access this issue and all past issues at http://msucares.com/newsletters/vaccinium/index.html

If you have any suggestions, questions, or feedback please feel free to contact me!

Netting Grapevines Against Birds

Last year I had problems with birds destroying some grapes before I had the chance to harvest them (full disclosure: I had several conferences last year that I attended while it was close to harvest time.  I rolled the dice that the fruit would still be there when I got back — no such luck). This year I am taking no chances!  Last week the bird netting went up on two of the four rows in the vineyard and this week the other two will be covered as well.  Since the vineyard is so small, it was relatively easy to put the netting over the rows and secure it.  Below are a few photos (taken by Richelle Stafne) of the process.

Throwing the netting over the row.  It helps to be tall.

Throwing the netting over the row. It helps to be tall.

Pulling the netting over the vines to make sure it covers the canopy.

Pulling the netting over the vines to make sure it covers the canopy.

Securing the netting by using zip ties. Other materials can be used such as string, twine, or bread ties. The netting was tied to the irrigation wire with the zip ties.

Securing the netting by using zip ties. Other materials can be used such as string, twine, or bread ties. The netting was tied to the irrigation wire with the zip ties.

The job is finished and we admire our efforts while sweating in 90+F heat and humidity.

The job is finished and we admire our efforts while sweating in 90+F heat and humidity.

The netting will remain on until harvest.  Once all fruit is harvested it will be removed and stored for next year.  Netting is an added expense to the vineyard and it makes management more difficult, but it is a necessity to protect the fruit from birds. There are different kinds of netting, some will last longer than others (and hence are more expensive), so it depends on an individual managers needs which kind to purchase.  Tractor implements are available to help with this process in large-scale operations.

Follow-up on White Drupelets in Blackberries

Yesterday I posted on why white drupelets occur in blackberries.  Well, the “why” that we know or think we know.  I also looked at the genetic make-up of certain cultivars.  Today, I went into the blackberry plantings here in Poplarville looking for white drupelets.  Since the season is almost over on some cultivars it wasn’t easy — there just weren’t enough berries, but I did find a few.  I was able to find them on ‘Ouachita’, ‘Kiowa’, ‘Chickasaw’, and ‘Sweetie Pie’.  I took some data on it too.  I harvested all the berries I could find that had white drupelets.  I counted the number of berries for each cultivar and from each berry counted the number of white drupelets.  I got an average and a range.  Plus, I took Brix measurement of the sugar content in the white drupelets compared to normal drupelets (I only did this for ‘Sweetie Pie’ because it was the only one that had a large enough sample).  Below is what I found:

Cultivar     # of berries    Avg. # white drup.    Range    Brix (white) Brix (normal)

‘Ouachita’       2                          2                   1-3

‘Kiowa’            5                          4.4                1-13

‘Chickasaw’    6                           2.7                1-9

‘Sweetie Pie’   45                         2.9                1-17        3.9             10.2

You may recall from yesterday that I broke down the genetic components of ‘Apache’ and ‘Kiowa’.  I will do that again for those I looked at today.

Ouachita:

Thornfree 25%, Brazos 25%, Darrow 17.1875%, OP (unknown) 18.75%, SIUS 68-1-8 12.5%, and US 1482 1.5625%

Kiowa:

Brazos 50%, Thornfree 18.75%, Darrow 12.5%, Wells Beauty 12.5%, and Brainerd 6.25%

Chickasaw:

Darrow 43.75%, Brazos 31.25%, Thornfree 12.5%, and Wells Beauty 12.5%

Sweetie Pie:

Brazos 43.75%, Humble 25%, Thornfree 18.75%, and Darrow 12.5%

As you can see ‘Brazos’, ‘Darrow’, and ‘Thornfree’ are mixed up in all of these cultivars.  Clark and Moore (2005) report that ‘Ouachita’ had low to no incidence of white drupelet in Arkansas. It has 25% ‘Brazos’ compared to ‘Kiowa’ at 50%, ‘Sweetie Pie’ at 43.75%, and ‘Apache’ at 31.25%. It appears likely that ‘Brazos’ has a role, but the extent is unknown. The field data doesn’t really tell us much because of the lack of replication and the few number of data points.  But with more it may be able to narrow down the genetic culprit of white drupelet.

The sugar content of the white drupelets was substantially lower than normal drupelets.  To me this suggests that the sugar may have not been there to begin with.  The texture and thickness of the skin are different than normal drupelets. At what stage does the drupelet abort from normal development?  This type of thing would be very difficult (or impossible) to replicate in a controlled environment.  I will continue to look at this issue and perhaps do a more in-depth study next year.

Below are some ‘Sweetie Pie’ fruit with white drupelets.  Just because it had the most white drupelets of the cultivars I looked at, it should not be an indictment of this cultivar.  It is later ripening that the others and thus had more fruit to sample.

'Sweetie Pie' fruit with white drupelets

‘Sweetie Pie’ fruit with white drupelets

Clark, J.R. and J.N. Moore. 2005. ‘Ouachita’ Thornless Blackberry. HortScience 40:258-260.

The Problem of White Drupelets in Blackberries

It is June, the month for harvest of blackberries in many areas.  Unfortunately, along with ripe fruit we also see other problems crop up.  This year I have seen pollination problems due to rain, SWD damage, stink bug damage, cane borers, anthracnose, and white drupelets.  So, what causes these white (or tan) colored drupelets? For quite some time no one knew what caused it (and we probably still don’t with 100% certainty).  Early theories revolved around insect damage (stink bugs, mites) or sunscald.

There are some very good descriptions and photos on the Team Rubus blog out of NC State and the UC IPM website.  I would encourage you to visit those sites.  Below is a photo of the problem in case you are not familiar with it.

White druplets on blackberry fruit

White druplets on blackberry fruit

The University of Arkansas-released cultivars Apache and Kiowa are most often mentioned as having this problem.  I would say that Apache has it most prominently.  Both the NC State and UC websites talk about the environmental conditions that contribute to this abiotic condition (abrupt increases in temperature, wind, low humidity) in concert with UV-radiation on the drupelet. The descriptions also talk about “tolerance” to the condition.  That would imply a genotype x environment interaction.  Since certain cultivars exhibit worse symptoms than others there is a genetic component that might be able to be exploited to reduce this problem in future cultivars.  But do we understand fully where it comes from (who is the offending progenitor)?

I broke down the parentage for both ‘Apache’ and ‘Kiowa’ to look for common ancestors.  The percentages are below:

Apache:

Thornfree 31.25%, Darrow 31.25%, Brazos 31.25%, Merton Thornless 4.6875%, and Eldorado 1.5625%

Kiowa:

Brazos 50%, Thornfree 18.75%, Darrow 12.5%, Wells Beauty 12.5%, and Brainerd 6.25%

Both of these cultivars have ‘Brazos’ in a significant portion of their parentage (>31.25%).  ‘Thornfree’ (US 1410 x US 1414), ‘Brazos’ (F2 of ‘Lawton’ x ‘Nessberry’), and ‘Darrow’ (NY 15826 x ‘Hedrick’) are in both cultivars and make up a large portion of their genetic makeup.  ‘Eldorado’ also is on both sides, but in a very small percentage (‘Eldorado’ is a parent of ‘Hedrick’ which is a parent of ‘Darrow’).

Now, this doesn’t get us to the answer — more analysis and experimentation needs to be done — but it seems likely that one of these three (or perhaps more than one) has lent genes that result in white drupelet.  Looking at the pedigrees along with real world, in-field data, would narrow it down farther yet.  We don’t know what the factors are that lead to the condition — skin thickness? pigment stability? These are possible hypotheses to follow up on.

With the warmer earth we are experiencing, it seems likely that this problem will continue to manifest in many growing areas.  New selections are being looked at to reduce this problem, but it may not be entirely eliminated.

Anthracnose on Bunch Grapes

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.

Severe anthracnose infection on Victoria Red grape cluster

Severe anthracnose infection on Victoria Red grape cluster

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:

http://www.smallfruits.org/smallfruitsregguide/Guides/2015/BunchGrapeSprayGuide2015.pdf

Fruit Splitting in Blueberries

The prodigious and regular rainfall we have experienced this Spring may be good for some things, but it is not good for ripening blueberries.  As you can see in the photo below, excess rainfall can cause blueberry fruit to split rendering it unsaleable and inedible.

Split Blueberry Fruit

Split Blueberry Fruit Caused by Excess Rainfall

So, how does this happen?  First off, water splitting happens in other fruits too.  More study has been done on cherries than most other fruits.  Reasons that cherries split are related to cultivar, fruit maturity, temperature of the water that hits the fruit, temperature of the fruit itself, duration of wetness, sugar content, fruit firmness, turgor pressure within the fruit, relative humidity, soil moisture, permeability of the skin and elasticity of the skin.  In blueberries, studies have shown that absorbed water through the skin is one reason, but also via root system uptake (although less so than direct contact).  The incidence of rain-caused splitting is very cultivar dependent and that cultivars with firmer fruit may be more susceptible to splitting.  What, within the fruit itself, could lead to this?  Some studies have suggested that in some cultivars the amount of air-filled spaces between cells could allow more water to enter but not split.  Another stated that cells that weakly adhere to each other may split more readily. A recent study showed that there is a moderately high heritability for fruit splitting, suggesting that this trait can be improved to some degree through plant breeding.

A past survey of MS and LA growers found that fruit splitting could reduce marketable yield by as much as 20% in some cultivars.  This means that cultivar choice is very important to avoid this type of damage.  Results from different studies mostly agree on results of what cultivars split more than others.  Below I have put them into three different categories: ~10% split or less (Low); ~10-19% (Moderate); ~20+% (High).

Low: Alapaha, Austin, Premier, Magnolia, Jubilee

Moderate: Gulf Coast, Chaucer, Columbus, Powderblue, Ochlockonee, Vernon

High: Brightwell (there was discrepancy on this cultivar, but 2 of 3 studies showed it to be high), Climax, Tifblue, Pearl River

One study found that excluding rainfall from the plants (covering them) was not a sure way of eliminating split, although it did reduce it.  Also, fruit on plants that are overhead irrigated appear less likely to split than those on drip irrigation.  New products are now on the market that may help reduce fruit split damage. They have not been tested in Mississippi, but have been tested in Florida and Georgia with encouraging results.

For further information you may refer to the papers below:

D. Marshall et al. 2008. Blueberry splitting tendencies as predicted by fruit firmness. HortScience 43:567-570.

D. Marshall et al. 2007. Laboratory method to estimate rain-induced splitting in cultivated blueberries. HortScience 42:1551-1553.

D. Marshall et al. 2009. Water uptake threshold of rabbiteye blueberries and its influence on fruit splitting. HortScience 44:2035-2037.

D. Marshall et al. 2006. Splitting severity among rabbiteye blueberry cultivars in Mississippi and Louisiana. Intl. J. Fruit Science 6:77-81.

D.S. NeSmith. 2005. Evaluation of fruit cracking in rabbiteye blueberry germplasm. Southern Region Small Fruit Consortium Research Project Progress Report.

M. Dossett and C. Kempler. 2015. Heritability of fruit splitting tendency in blueberry. HortScience (in press) abstract.