First 2016 Issue of Mississippi Vaccinium Journal

Dear Faithful Readers:

Below is the link to the latest issue of the Mississippi Vaccinium Journal.  In this issue we cover new cultivars, diseases, presentations from the Mississippi Blueberry Education Workshop, and more.

Mississippi Vaccinium Journal Volume 5 Issue 1

As always, you can see past issues at this link: http://msucares.com/newsletters/vaccinium/index.html

If you have any questions or comments, please contact me.

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Presentations from the 2016 Mississippi Blueberry Education Workshop

The 2016 Mississippi Blueberry Education Workshop was held on January 14 in Hattiesburg. There were 55 attendees that heard the following speakers.  To access a PDF copy of each talk (if available), click the linked title.

Speaker Line-Up and Schedule:

1:10-1:40 pm Dr. James Barnes (MSU-ES):

The Economics of Marketing Blueberries Using Facebook: Some Lessons Learned from the Mississippi Bricks to Clicks Extension Program

1:40-2:10 pm Chaille Clements (Mississippi Dept. of Agriculture and Commerce):

Farm to School Presentation (Market Ready)

2:10-2:40 pm Dr. Eric Stafne (MSU-ES):

Update on Harvest-aid Technologies to Improve Harvest Efficiency

 

2:40-3:00 pm Mechanical Harvest Survey and Break

 

3:00-3:30 pm Dr. Rebecca Melanson (MSU-ES):

Recognizing and Managing Blueberry Diseases

3:30-4:00 pm Dr. Donna Marshall-Shaw (USDA-ARS, Poplarville):

Blueberry Cultivars for Small and Local Markets

 

4:00-5:00 pm Questions/Discussion/Evaluation

 

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.

A Visit From Dr. Scott NeSmith, UGA Blueberry Breeder

Last week, Dr. Scott NeSmith, blueberry breeder from the University of Georgia, came to Poplarville for a visit.  We talked about the current state of the Mississippi blueberry industry (as well as what is happening in Georgia).  He stated that some early blooms may have got nipped some from cold events in the last few weeks there, but he was unsure how much loss to attribute to it.  He was really interested in the cultivars currently being grown in Mississippi, so we headed on over to visit Luis Monterde.  At his farm we saw most of the bushes in full bloom, with scads of pollinators buzzing from bush to bush.  Dr. NeSmith asked if he had any Georgia releases.  Luis said yes (Alapaha and Vernon) and showed them to us.  Luis was high on Alapaha but expressed some reservations on Vernon.  Dr. NeSmith said that in Georgia, high fertility was to the detriment of Vernon, which preferred low fertility management.  He also suggested that the new cultivars Titan and Krewer might be good options here in Mississippi.  As plants have been difficult to get, not much of it is planted here yet, so only time will tell on that.  He did say they would split in the rain (Titan more so than Krewer).  The issue of growing southern highbush blueberries also arose in our conversation.  Luis said he has mostly given up on them (although he had one row), as they were difficult to keep alive for very long.  One suggestion Dr. NeSmith had was to try Camellia and/or Suziblue.  He believes they are “tougher” plants and can stand up better than other cultivars that have been tried in the past.  Luis asked him what Georgia growers were doing with Premier, and Dr. NeSmith responded “pulling it out” due to the unreliable yields.  After about 1.5 hours, we bid Luis goodbye and I took Dr. NeSmith back to Wiggins where he was staying.  He doesn’t make it over here very often, so it was good to be able to spend some time with him and pick his brain about new potential cultivars for Mississippi.

Luis Monterde (left) and Dr. Scott NeSmith (right)

Luis Monterde (left) and Dr. Scott NeSmith (right)