Brief Summary of Minutes of Annual Meeting

A. Acquisitions and associated work

In 2017, we collected 17 germplasm accessions from an expedition to Colorado and New Mexico with the support of K. Williams of the USDA Plant Exploration office at Beltsville.  We found potatoes in new places at the northeast extreme of the range.  Some were extremely robust populations (below left) but some places (below right) were extremely stressed (although these small dead plants often had one mature tuber and fruit).  A detailed trip report is available on GRIN, attached to every new accession record.  We also sought and received 19 new clonal breeding stocks and cultivars from various donors.  We continued the process of acquiring clones for which PVP has expired.

The NRSP-6 web page (http://www.ars-grin.gov/nr6) was updated to include all new stocks and screening information.  Clients who have ordered from NRSP-6 within the past four years were contacted three times in 2017, informing them of new stocks of true seed, tubers, in vitro plantlets, or other samples.  We used email and the website to extend technical instructions of various types. 

B. Classification

Dr. Spooner continued work on a monograph of species of northern South America.  The PTIS herbarium was moved to the University of Wisconsin (see... https://news.wisc.edu/valuable-potato-specimens-transferred-to-wisconsin-state-herbarium/).  We continued making high quality digital images of plants, including tubers, of the species microdontum and boliviense to attach to accession records in GRIN.  We continued research on crafting core collections within species stoloniferum and bolviense. 

C. Preservation and Evaluation

Nearly two acres of individual field plots for numerous evaluation experiments were grown at the UW Ag Research Station at Hancock, Wisconsin.  Four large screenhouses at Sturgeon Bay were used for other such experiments grown in pots.  

1. Propagation: In 2017, we hand-pollinated 167 families of 20 plants each in the greenhouse for seed increase and performed 3,150 in vitro transfers to maintain fresh propagules of clonal stocks.  Alternate methods of emasculation were systematically tested (at left).

2. Germplasm health monitoring: We did 589 tests for PSTV and 217 more for the six common potato viruses. 

3. Characterization: We did 1,567 replicated germination tests, 25 ploidy evaluations and 21 tetrazolium seed viability assays.  These statistics do not include the hundreds of assays performed researching ways to improve the efficiency of seed germination and ploidy determinations. 

4. Evaluation and Technology:

Peru connection:  With Peru cooperators and J. Palta of University of Wisconsin, we continue research and breeding for wart, drought, frost, late blight, tuber calcium.  L. Palomino, INIA breeder (at right), holds one of our named selections being released in the Cusco region.  We also continued strong collaboration on projects with colleagues in the NGO CITE-papa, and our sister genebank, CIP, in Lima.

Egg-yolk specialty potatoes:  We continued evaluation of the best selections, and recurrent breeding.  With cooperators at University of Minnesota, we began the process of creating an inbred diploid form of Criolla with excellent color, taste and tuber dormancy.

Genotyping genebank holdings:  We cooperated with CIP colleagues to GBS genotype multiple individuals from ten populations to assess heterogeneity and effects of seed increase.  Similar markers are being generated on 50 individuals of microdontum with PepsiCo-FritoLay to look for markers associated with Dickeya resistance and other traits.  With Oregon cooperators, we identified SolCap SNPs associated with high folate. 

Somaclonal and other variants:  We produced 14 somaclonal variants to see if this technique, which uses tissue culture technology and expertise already established at the genebank, can improve elite selections for various traits.  Finding and using novel diversity is our primary mission.  The unique extreme fasciation in the jamesii accession found in 2017 are the kind of opportunities we look for.

Remote grow-outs:  With New Mexico State University cooperators at Farmington, we again conducted remote field tuber grow-outs providing tissue for multiple analyses (below right).

Tuber freezing:  We are wrapping up data collection on the first reported significant tuber freezing tolerance in potato.  If we can dissect the physiology and apply it to other germplasm, it might lead to an efficient long-term germplasm storage tool, or other uses in the industry.  We reported this finding at the annual meeting of the Potato Association of America.

D. Distribution

Distribution of germplasm is at the heart of our service.  The volume and types of stocks sent to various consignee categories are summarized in the table below.  In 2017, total distributions were up about 25% over historic averages:  229 domestic orders to clients in 35 states and 17 foreign orders to 9 other countries.  About 1/3 of the domestic orders are for public breeders and geneticists, 1/3 for pathology, physiology, entomology, taxonomy and education, and the remaining 1/3 for private germplasm users.

In 2017 we maintained the popular offering of 100 cultivars as tubers by devising and implementing an iron-clad disease control and quarantine program for their production (full details available at our website).  We now only offer tubers of wild species by special order.

Units of Germplasm Sent

Category         Seed    TU        IV        DNA    Plants     Total

Domestic          4,200   2,993   1,597    920      1,173    10,883

Foreign              933         0        285        0          0        1,218

Total                 5,133    2,993   1,882     920     1,173    12,101

Types of stocks sent/(number of seeds, tubers or plantlets per standard shipping unit): Seed = True Seeds/(50), TU = Tuber Clones/(3), IV = in vitro/(3), DNA = dried leaf or tuber samples/(1), Plants = Rooted Cuttings/(1), Herb = Herbarium Specimens/(1).

E. Outreach

We made a trip to Peru in November to solidify our cooperative programs in Puno, Cusco, and Lima.  Bamberg chaired the Potato CGC and served as Editor in Chief of AJPR.  We hosted visitors from Kenya, Ukraine, Brazil, Uganda, Peru, and University of Minnesota.  Staff member A. del Rio was invited to be on the organizing committee of the Latin American Potato Association Meeting in Cusco, Peru in May, 2018.  We have been asked to host the National Plant Germplasm Coordinating Committee meeting in May 2018.  We volunteered presentations with published abstracts: Two at PAA in Fargo, invited presentation at CSSA meeting in Phoenix and were invited to write a book chapter on nutritional opportunities in new potato outlets.

We hired and managed two undergrad students as summer interns with research projects.  One of these projects (systematic assessment of ploidy estimation techniques) has already been presented at a national germplasm meeting.

All germplasm documentation, and details about technology, outreach, and staff publications are available at our website:  http://www.ars-grin.gov/nr6/.

Bamberg, JB, CJ Fernandez, and AH del Rio.  2017.  Extra soil fertilization of mother plants increases botanical seed yield but not long-term germination in wild Solanum (potato) species.  American Journal of Potato Research 94:583-587.

del Rio A.H., Obregon C., Bamberg J.B., Petrick J., Bula R., de la Calle F. (2017)  Validation of high-quality potato seed production protocol under controlled conditions (CETS System) in cultivated potato species (Solanum tuberosum L.) ALAP Journal 21(2): 71-78.

Bamberg, JB, del Rio, A, Jansky, J and Ellis, D.  2017.  Ensuring the genetic diversity of potatoes.  In:  Achieving sustainable cultivation of potatoes Vol.1 (Ed. Prof. Gefu Wang-Pruski).  In Press.