Tuesday, September 23, 2014

Fingerprinting Raspberries and Blackberries

This past summer Team Rubus presented a poster, "Who’s your raspberry daddy?" at two Research Station field days in June. And in August, we presented another poster titled "Comparative diversity analysis of Southeastern Rubus germplasm through molecular and pedigree techniques" at the International Horticultural Congress. Although the titles of the presentations were different, the presentations were essentially the same. Both were discussing how our breeding program has incorporated fingerprinting technology into our program. Below is a brief synopsis of this work.

Why do we need fingerprints?
- Can sort mix ups in research and grower fields and nurseries
- Distinguish between closely related varieties
- Potential patent protection (not used yet for Rubus)
- Determine how diverse germplasm is in a breeding program

How do we produce fingerprints?
- Collect young leaf samples in spring or summer
- Extract DNA from leaves, and tag each plant using 6 DNA markers that are specific to red raspberry (Bassil et al.)

- Each genotype/variety/cultivar will have a unique profile  or "fingerprint" for the 6 DNA markers
- The "fingerprint" of each sample is matched to a reference profile in our database, to ensure it is true to type (actually the genotype/cultivar/variety which it is labelled as).

This is a slide from one of the presentations. The first picture shows some of the leaf tissue​, ​mortar​ and pestle​ (old fashion way to grind the tissue), the second picture is of extracted DNA in ​test tubes being prepared for analyses. ​T​he 3rd image is of a PCR printout, and the green bands and blue bands represent ​the DNA fragments, separated by size.  Green and blue are two different markers, which are analyzed simultaneously.​

Here is an example what the data looks like from our selection NC 654 which is a cross between Mandarin (mom) and Willamette (dad). For the DNA marker Meek19, Mandarin, peaks at 170/186, and Willamette, peaks at 170/174.  NC 654 (child) peaks at 170/174.  We can verify that Mandarin and Willamette are indeed the parents of NC 654 using Meek 19, whereby the 170 peaks comes from Mandarin and the 174 peak comes from Willamette. This combination of peaks is unique to NC 654. 

In addition, through some modifications of the established protocol for red raspberry, we were able to determine that we could use these same markers for black raspberry and blackberry.

Bassil NV, Nyberg A, Hummer KE, Graham J, Dosset M, Finn CE. A Universal Fingerprinting Set for Red Raspberry. Proc. Xth Intl. Rubus and Ribes Symp. Acta Hort. 946. ISHS: 2012.

Wednesday, September 17, 2014

Blackberry On-Farm Field Day

From: Daniel Shires, Area Ag. Extension Agent
When: Friday October 10, 2014
Time: 1:00 PM to 3:30PM
Killdeer Farms,
300 Goforth Road
Kings Mountain, NC 28086

On behalf of the NC Commercial Blackberry and Raspberry Growers Association and the NC Cooperative Extension Service you are invited to attend our upcoming Fall Blackberry Field Day. This will be a great opportunity to learn from Extension Specialists and see equipment demonstration on a real-life farm setting. The field day is free to anyone who wishes to attend. Since this is an outside event: dress appropriately and bring a lawn chair if you wish. Please RSVP to Annie Thompson (Extension Secretary) at
704-482-4365 by Wednesday October 8th if you plan on attending.

1:00 to 1:15…Registration
1:15 to 1:30…Welcome from Ervin Lineberger, Killdeer Farms
1:30 to 2:00…Spotted Wing Drosophila (Lauren Diepenbrock & Katie Swoboda, NCSU)              
2:00 to 2:30…Hand-washing stations and mobile cooling unit (Daniel Shires, NCCE)
2:30 to 3:00…New Herbicides (Wayne Mitchem, NCSU)

3:00 to 3:30…Disease vs Virus (Andy Rollins, Clemson Extension)

Tuesday, September 9, 2014

Evaluation of raspberries for tunnel and field production in North Carolina

Evaluation of raspberries for tunnel and field production in North Carolina

Penelope Perkins-Veazie and Gina Fernandez

Raspberries are a highly popular fruit with consumers, and also a high value crop for producers.  One of the major limitations to production in North Carolina is heat.  Raspberry plants often respond to heat stress by reducing fruit size.  Also, the warm temperatures encountered during harvest can lead to a very short postharvest loss, as berries are softer and easier to bruise when harvested warm.  In this multi-year study, raspberry cultivars and NC breeding selections were evaluated in high tunnel and field production systems.

Harvest and Handling:  Pick firm fruit and place in shallow vented containers. Red raspberries can be harvested when pink and come off the plant with minimal tugging. The most often used container is a plastic ½ pint with vents in top, bottom, and sides to aid air flow. Containers for raspberries should be shallow, as only a few layers of berries should be in the box to prevent fruit collapse and leaking.  The best time to pick raspberries is early in the morning, while fruit are still cool.  Picking wet raspberries after rainfall or heavy dew is not recommended as the shelf life quickly drops.
Raspberries can be cooled at temperatures slightly below freezing (31 F) as the high sugar content acts as an anti-freeze.  It is better to cool fruit soon after harvest and hold raspberries below 40°F as long as possible.  If cooling is delayed, storage life is lost in proportion to the delay (a one hour delay can mean a one day loss in shelf life). 

Best cultivars and selections for postharvest life when grown in North Carolina. These suggestions are based on several years trials at research stations in NC. Check http://rubus.ces.ncsu.edu for yield data of these selections and cultivars. Note that some yield data is still being collected in fall 2014.
10-14 day shelf life if held at 35°F within 2 hours from harvest
Joan J

7-10 day shelf life            
For local use only (less than 5 days)