Truffles

As the truffle industry in North Carolina is growing, there has become a need to more fully understand how to produce truffles in this region. The first step is to understand the level of persistence of the truffle on roots. As a response to the need for a testing service, we are providing a service to test roots and soil for the presence of Tuber melanosporum (black Périgord truffle). For any testing, please contact Inga Meadows before you sample and ship to be sure they know to expect them.

As of July 1, 2020. the cost for testing roots will increase. See below for new pricing structure. Now that we have a good idea of the time it takes to sample and run the DNA tests, we have re-evaluated our pricing structure and have realized we have been undercharging. Please note the changes and plan accordingly. 

There are three different types of testing we can do:

1. Evaluate truffles for inoculating trees for trueness to identification.

Pieces (approx. 1 cm x 1 cm x 1 cm) of each truffle to be used for inoculation should be removed using a clean, sharp knife. We can test for Tuber melanosporum, T. aestivum, T. brumale, T. borchii and other species upon request.

There are two ways to ship: (1) immediately freeze truffle pieces in labeled plastic bags. Use dry ice to ship the frozen pieces overnight to avoid secondary organisms colonizing the tissue. (2) Dehydrate the pieces using a food dehydrator. Ship them in sealed, labeled plastic bags overnight.

Cost for truffle testing (option 1): $200 (up to ten truffles; $20 per additional truffle)

2. Evaluate T. melanosporum colonization on roots and soil from inoculated tree seedlings.

If you are sending inoculated tree seedlings, please send whole trees with a sealed plastic bag around the soil to avoid the soil moving around during shipment. A minimum of 5 trees per 1,000 trees should be tested, although 8 is recommended. A minimum of 5 trees if the lot is less than 1,000 trees should be tested. (Cost listed below).

We can evaluate tree seedlings that have been inoculated with a species other than T. melanosporum, such as T. aestivum, T. brumale, or select other species upon request. As we are not as familiar with morphology on other species and the limited assays available to us will determine the level of information we can provide.

3. Evaluate T. melanosporum colonization on roots and soil from an existing orchard.

For assays 2 and 3, we test roots for the presence of Tuber melanosporum using an assay that can quantify the DNA of T. melanosporum in soil. We also take pictures of the roots we received for documentation. If we suspect root colonization by other mycorrhiza, we may be able to provide additional services to determine the identity of the competing fungi, if requested by the grower, for an additional fee. (Cost list below)

As for the seedlings, we can evaluate tree seedlings that have been inoculated with a species other than T. melanosporum, such as T. aestivum, T. brumale, or select other species upon request. As we are not as familiar with morphology on other species and the limited assays available to us will determine the level of information we can provide.

Click here for INSTRUCTIONS to sample roots and soil from an existing orchard.

Click here for truffle testing SAMPLE FORM

Click here for an EXAMPLE truffiére map (Prepared by Leo Stefanile)

Cost for options 2 and 3 (updated 12/2018): $60 per sample

Cost for options 2 and 3 effective 7/1/2020: $90 per sample

If you plan to collect samples, please email or call Inga Meadows before you collect to ensure the timing is appropriate (inga_meadows@ncsu.edu OR (828) 456-3943).

It is best to ship samples overnight or express delivery so that they arrive at the lab Mon-Fri. If you collect late in the week, keep your samples in the fridge until you can ship them; however, it is best to collect samples within 24 hours of shipping.

Important: If you are shipping from outside North Carolina, please print this APHIS permit twice. One copy can be placed inside the package and the second copy needs to be on the outside of package. Taping a ziploc bag to the package with the folded permit is fine. If shipping within North Carolina, you do not need the permit.

Samples should be shipped overnight or express delivery to:

Inga Meadows

265 Test Farm Road

Waynesville, NC 28786

 

Root tips colonized by Tuber melanosporum
(Photo by Kelly Gaskill)

Ectomycorrhizal root tips (not Tuber melanosporum) (Photo by Kelly Gaskill)

Ectomycorrhizal root tips (not Tuber melanosporum)
(Photo by Kelly Gaskill)

Root tips colonized by Scleroderma sp.

Root tips colonized by Scleroderma sp.
(Photo by Kelly Gaskill)