The North Dakota Agricultural Experiment Station announces the release of Dakota Diamond, an exceptionally high-yielding potato cultivar suitable for chip processing and the fresh market. It also has resistance to common scab.

Dakota Diamond was tested as ND5822C-7. It originated from the cross of ND4103-2, an advanced selection from the North Dakota State University potato breeding program with chipping ability and some resistance to the Colorado potato beetle, and Dakota Pearl, a commercially accepted cold chipping cultivar released by the NDSU potato breeding program in 1999. Dakota Diamond combines the attributes of several wild potato species, including Solanum andigena, S. demissum, S. phureja, and purportedly, S. chacoense.

ND5822C-7 was selected for seeding at Langdon in 1995 and since has been evaluated elsewhere in North Dakota and at many North American locations. It was included in the North Central Potato Variety Trial in 2002 and 2003 and in the Snack Food Association/U.S. Potato Board Trial in 2003, 2004 and 2005.

"Dakota Diamond is named for its many attributes, including beautiful appearance, excellent chip quality, particularly from late-season storage; resistance to common scab; exceptionally high-yield potential; and in honor of the NDSU potato breeding program being part of the North Dakota Agriculture Experiment Station for 75 years," says Susie Thompson, NDSU potato breeder.

The yield potential for Dakota Diamond is very high under irrigated and nonirrigated production conditions, often averaging near 500 hundredweight per acre under non-irrigated conditions. Dakota Diamond has been tested in yield trials in North Dakota since 1998. Generally, it was the top yielder and consistently produced a high percentage of U.S. No. 1 tubers. The yield per acre of these marketable tubers exceeds the total yield for most other entries.

Chip processors and producers continue to look for a cultivar with the potential to process acceptably after long-term storage. Based on this need, the NDSU potato breeding program, in collaboration with Marty Glynn, USDA-Agriculture Research Service Potato Research in East Grand Forks, Minn., followed Dakota Diamond sugar and chip color through 12 months of storage at multiple temperatures. The profile indicates the potential for Dakota Diamond to be processed acceptably for nearly a year from 45 degrees.

Dakota Diamond has high specific gravity, an indicator of dry matter content, averaging 1.090 across irrigated or nonirrigated trials. High dry-matter potatoes result in a mealy textured product, yield more chips or fries from the raw product, have reduced cooking times, and best of all, absorb less oil.


Dakota Diamond has a vigorous, semierect to sprawling vine, with medium-late maturity. It blooms profusely and heavy fruiting occurs in the field. Like its paternal parent, Dakota Pearl, Dakota Diamond tubers have beautiful, bright white skin and flesh. The tubers are round, uniform in size, smooth and have shallow eyes.

Grower and research trial experience indicates Dakota Diamond requires minimal inputs for nitrogen fertility and may require reduced rates and/or frequencies of insecticidal control for Colorado potato beetle. Growers may benefit from planting it first, providing nitrogen in the 130- to 150-pound range and monitoring tuber size beginning in August. Tubers are set later than check cultivars; excessive nitrogen will delay tuberization in favor of vine production. A 12-inch row spacing maximizes production of A-sized tubers, limiting the potential for hollow heart.

Dakota Diamond possesses resistance to common scab, moderate resistance to pink rot and exhibits preferential avoidance by Colorado potato beetle in choice cage studies. According to NDSU plant pathologists, Dakota Diamond expresses typical symptoms of bacterial ring rot. It is moderately susceptible to Pythium leak and is susceptible to foliar late blight and potato virus Y.

"While Dakota Diamond is most suitable for the chip processing market, it performs similarly to other chip cultivars in sensory evaluations," Thompson says. "Texture and flavor scores have been similar to those of Atlantic, Dakota Crisp and Dakota Pearl for boiling, baking and microwaving, in addition to flake production."

Certified seed of Dakota Diamond is available from certified seed producers in North Dakota, Minnesota and Nebraska. Tissue culture-based, limited-generation seed production (micro-propagated plantlets, mini-tuber production) is available from the North Dakota State Seed Department and operations in other states.