The MSU Potato
Breeding and Genetics program has a potato variety identification
service via isozyme electrophoresis that has been in operation since
1990. A fingerprint database is maintained with over 200 varieties.
This variety fingerprint method is rapid, economical, and accurate. In
addition, either leaf or tuber tissue can be used for the analysis.
The laboratory
protocol is based upon research of D. S. Douches and K. Ludlam (1991,
American Potato Journal 68:767-780). Standard horizontal starch
electrophoresis is employed. To facilitate the interpretation of the
banding pattern of the variety, duplicated samples are run side by side
on the gel. Following electrophoresis, the isozyme banding patterns are
resolved via enzyme-specific stains. The discrete bands for each
isozyme locus are transcribed to a database for sorting. Usually 10
loci are scored to discriminate the varieties. The summation of the
electrophoretic pattern for these 10 loci is referred to as its
fingerprint.
The limitations requiring the use of fresh tissue for isozyme fingerprinting are removed by using a DNA-based system. DNA can be isolated from various fresh and freeze-dried tissue samples and isolated DNA samples can also be archived for extended storage. Freedom from fresh tissue also facilitates transportation of material across country borders that can be restricted due to phytosanitary regulations.
Simple sequence repeats (SSRs or microsatellites) are tandemly repeated short oligonucleotide sequences that are flanked by conserved DNA sequences. SSRs can provide a reliable, efficient, and applied DNA-based fingerprinting system for potato. An example of its use is shown below. The use of this fingerprinting method is described in the journal article:
Coombs,
J.
J.,
L.M. Frank, D.S. Douches. 2004.
An applied fingerprinting system for cultivated potato using simple
sequence
repeats. Amer. J. Potato Res. 81:
243-250.
Please contact: Dr. David
Douches for further information
about these services.
Crop and Soil Science Dept.
Plant and Soil Science Building
Michigan State University
East Lansing, MI 48824
(517)355-0271x198
e-mail: douchesd@msu.edu
