The latest issue of Mississippi Vaccinium Journal is now available! Read it here: Mississippi Vaccinium Journal Vol 7 Issue 1
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.
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.
The 2016 Mississippi Blueberry Educational Workshop will be held in Hattiesburg on January 14, 2016 from 1-5pm. Several topics will be covered including mechanized harvest, Farm-to-School, Social Media marketing, blueberry cultivars, and disease control basics. Everyone with an interest in blueberries is invited to attend. See the information below for details on the program.
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.
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.
Glyphosate (i.e. RoundUp) has been getting a lot of bad press lately, mainly as it relates to GMOs. This post is not about GMOs, but rather prudent use of herbicides. Herbicides are great tools, but must be used with caution. First of all, the label is the law, so any instruction supplied on the side of the herbicide container is what one must follow for application (an online version of the label IS NOT considered to equivalent to the actual one on the container). Second, make sure the tanks you use are either dedicated for the type of pesticide being applied (one for herbicides, one for insecticides and/or fungicides, etc.). Third, clean out the tank, especially if you are changing products. Residue can lead to unintended consequences. Fourth, understand the mode of action and rotate chemistries to reduce the chance for weed resistance. Fifth, know which weeds you want to control and use the best product for those weeds. Sixth, timing of application is VERY important for control — knowing the weed life cycle and timing the herbicide application with the most vulnerable period will yield the best results. There are some rules to follow when using any herbicide, but since glyphosate is so ubiquitous some closer scrutiny is needed.
Now, on to glyphosate specifically. It is a systemic herbicide, meaning the product is taken up by the plant and translocated within it. Glyphosate inhibits plant enzyme production, thus disruption its ability to synthesize certain amino acids. So, it is very good at killing a broad spectrum of weed species. Unfortunately, if not applied properly, it can be very good at killing fruit and nut plants too. Since RoundUp went off patent, there are many glyphosate products on the market now. Some have very different percent active ingredient. Knowing the percent active ingredient will tell one how much water to mix it with prior to application. Still, sometimes errors are made and a high price is paid.
A recent visit I had to a blueberry field revealed significant damage from glyphosate application. The grower had good intentions and had used glyphosate without problem for years, he had run out of one container and switched to another new one. Several rows had no problems (application with the first container), but the next rows had significant death. Why? The amount of active ingredient was different, but the applicator mixed the same amount for application. The plants may never recover and probably need to be removed. The photo below tells the story. If in any doubt about applying herbicides properly, contact a local county Extension office for help.
The new issue of the Mississippi Vaccinium Journal is now available. Inside are articles on southern blueberry pollinators, a visit with Dr. Scott NeSmith from University of Georgia, and resources from recent meetings. As always you can see past issues here: http://msucares.com/newsletters/vaccinium/index.html
If you wish to receive it directly via email, then email me and I will add you to the list. Click the link below to access the current issue:
Below is a video from Mississippi Public Broadcasting (MPB) and their program Mississippi Roads. This video is about the Mississippi blueberry industry. I even have a short cameo.
A Road Trip To A Blueberry Jubilee And An Extra Table
The newest episode of Mississippi Roads features the Blueberry Jubilee held in the south Mississippi town of Poplarville and Extra Table, a philanthropy founded by renowned Hattiesburg chef, Robert St. John. The episode will air Oct. 16 at 7 p.m. on MPB TV.Mississippi Roads gets a taste of Poplarville at its 31st annual Blueberry Jubilee. More than 10,000 people flood downtown Poplarville every year for the festival. Visitors make the trip for the arts and crafts, storytelling, live entertainment and, of course, the amazing food they can only find at the jubilee. The proceeds of the Blueberry Jubilee provide grants to fund programs and projects that serve the community.Next, Mississippi Roads pulls up a chair at chef Robert St. John’s Extra Table. Extra Table is an organization that focuses on reducing the prevelance of food deserts and hunger in the state by stocking food banks and soup kitchens with healthy food.
In 2009, St. John received a call from a local food bank asking him for help—the food bank’s shelves were empty and 800 families needed food. So, St. John contacted Sysco, his restaurants’ food distributer, and delivered enough healthy food to stock the food bank and feed the 800 families. This got St. John thinking.
“What if every restaurant and home had an extra table to serve people in need? What would that look like?” said St. John.
In order to address the severe food insecurity problem facing his community, St. John partnered with Sysco and by 2011, Extra Table was delivering new healthy and nutritious food to agencies at below wholesale prices on a regular basis.
“Extra Table receives donations from private companies and individuals—100 percent of all donations go towards buying healthy food which we deliver directly to agencies keeping their shelves filled,” said St. John.
Extra Table cuts the food costs of the agencies it serves significantly. This enables the agencies to allocate those funds to programs that serve the community in other ways.
“The money that was going towards buying food is pumped directly into the community. The agencies use that money to provide things like after school programs and career prep workshops,” said St. John.
For more about the Blueberry Jubilee and Extra Table, tune in to MPB TV on Oct. 16 at 7 p.m. for Mississippi Roads.
Mississippi Public Broadcasting (MPB) provides instructional and public affairs programming to Mississippians through its statewide television and radio network. MPB enhances the work of educators, students, parents and learners of all ages by providing informative programming and educational resources. MPB’s locally-produced programming focuses on the people, resources and attractions that reflect Mississippi’s unique culture and diverse heritage. Children’s television programs constitute a major portion of the daytime and weekend morning schedules. MPB provides a valuable resource to Mississippians in disseminating information as part of the state’s emergency preparedness and response system. Since 1970, MPB has won over 400 national, regional and statewide awards, including Emmy®, Edward R. Murrow and Parents’ Choice Awards. For more information on MPB, its programs, mission or educational resources, please visit www.mpbonline.org.
October 9, 2014
The Walnut Caterpillar (aka Walnut Datana) (Datana integerrima) is a common pest of pecan trees. The adults are moths with light-brown wings marked with dark-brown, wavy lines. The hind wings are lighter brown and without lines. The moths are about 1.5 to 2 inches long, but this is not usually the life stage that is noticed by growers. It is the larvae that cause significant defoliation to plants. Immature larvae are reddish-brown with narrow, cream colored lines that extend the length of the body. Mature larvae are black, about 2 inches long and are covered with long, white or grayish hairs.
The Walnut Caterpillar overwinters as a pupa in the soil. The moths emerge in the spring and deposit white eggs in masses on the underside of leaves. These eggs result in the larvae that form a compact mass. These caterpillars molt several times during development. The larvae feed in groups, but unlike fall webworms (also common on pecans) they do not form webs. They are capable of eating all the leaves on small trees or entire limbs of larger trees.
Although common on walnut and pecan trees, the realsurprise this year is that I have reports of them feeding on blueberries (see photos below).
Above are three photos of the Walnut Caterpillar larvae. Below is the one photo of the resulting damage they can do. Significant defoliation can lead to poor winter hardiness and possible reduced fruitfulness next year.
So, what to do about them? There are a few options: cut out the branches with worms; use products that contain Spinosad in them (like common Leafminer & Tent Caterpillar Spray); or spray with Sevin (this also kills beneficial insects though). Most of the time the best option is the one to just remove the section of the plant with the larvae and dispose of it. Below are more links that cover this insect.
Kansas State: http://www.hfrr.ksu.edu/doc1741.ashx
At the 2014 American Society for Horticultural Science, Southern Region meeting held in Dallas, TX the Mississippi Vaccinium Journal was given a Blue Ribbon Extension Communication Award (see below). This is a great honor as the chosen communications must show a high degree of quality. While I have received this award in the past, this is the first time I have gotten one for work I’ve done at Mississippi State University. The MSVJ is a newsletter written for blueberry growers. It is published quarterly and it goes out as a pdf file via email to: all MSU extension personnel, direct subscribers, and all Gulf South Blueberry Growers Association members. If you are interested in receiving the MSVJ there are a few ways to do that: one is to email me and ask to have me send it to you directly, two is to be a member of the GSBGA or work for MSU Extension, three is to access current and past issues from MSUcares at this link (http://msucares.com/newsletters/vaccinium/index.html), and four is to get it from this blog at this link where all new issues are uploaded. I am pleased to have received the award and I look forward to editing and writing it for as long as it continues to be read. Special thanks goes to all the readers of the MSVJ, the USDA-ARS researchers in Poplarville who contribute content, and to Mike Neff, ASHS, for sending the image of me accepting the award. See images below about the award.
The photo below shows the actual award (which was kind of a pain to lug through the airport in Dallas as I was stuck there all night, but I digress…)