A P R I L 2 0 1 7 12 POTATO GROWER tubers with second growth, and many with jelly end. Growth cracks were common reason for culling for Ranger Russet, Umatilla Russet, ND113224C-3Russ (which also was more roundish under the Russet Burbank fertility regime), and were noted in ND050032-4Russ. Several advancing selections and industry standards had outstanding French fry color when fried at har- vest (field fry) and after storage at 45F for 8 weeks (Table 3). Many demonstrate sugar end resistance, and while most clones considered resistant to sugar ends had some, our rating of sugar ends is more stringent than that of the processors in an effort to identify durable resistance, and thus they are man- ageable during processing (see foot- note 3 on Table 3 for definition). ND8068-5Russ, which following many years of evaluation across many environments would be con- sidered to be resistant to sugar ends, did develop some in 2016. It is plau- sible that due to its very early matu- rity relative to all other clones in this full season trial, that tubers were over-mature after having been dead for weeks prior to harvest. Trial entries were also evaluated for specific gravity and internal defects (Table 1). The mean specific gravity was 1.0901 for the trial, with a range of 1.0762 to 1.1074 for ND113330- 1Russ and Dakota Trailblazer, respectively. Hollow heart/brown center was notable in ND 091933ABCR-7Russ, ND091933 ABCR-2Russ, Russet Burbank, ND102587AB-1Russ and ND060735- 4Russ. Trial entries are also evaluat- ed for blackspot and shatter bruise potential. Blackspot bruises result when polyphenol oxidase and tyro- sine combine within damaged cells due to tubers impacting objects dur- ing harvest and handling; the skin is usually not broken and bruises are difficult to detect without peeling. Ranger Russet serves as our suscepti- ble control and had a rating of 4.0. Growers should use best manage- ment practices to maximize the marketing of bruise-free tubers, including a pre-harvest irrigation if appropriate, maintain belts and con- veyors full of tubers and soil as the potatoes move through the har- vester, limit drops, and utilize padding on harvesters, in trucks, and on conveyors going into stor- age. Shatter bruise potential (Table 3) was evaluated following storage at 45F. No clone stood out as having significant potential for shatter, even those with high specific gravi- ty. Keeping tubers properly hydrat- ed prior to harvest, using bruise-free management techniques, harvesting above 45F, and minimizing damage, all limit shatters. Shatter bruises may be a possible entrance point for pathogens such as Fusarium gramin- earum, Fusarium sambucinum and Fusarium coeruleum. The trial identified many promising advancing dual-purpose (frozen pro- cessing and tablestock) russet selec- tions. The most advanced is ND8068-5Russ, a very early matur- ing selection, about seven to ten days earlier than standard Russet Norkotah. It will not compete with late season cultivars for yield; how- ever, it sizes early, is typey, and has potential as an early russet for pack- ing, or may be used for early pro- cessing in place of Shepody or Ranger Russet in mid-July. Our sincere thanks to Hoverson Farms for hosting this research trial. Thanks also to Richard Nilles, James Bjerke, Steffen Falde, and Ben Hintz for assistance from planting through grading and evaluations. Thanks also to the Northern Plains Potato Growers Association, the Minnesota Area II Research and Promotion Council, and NIFA Special Potato program for funding. The potato breeding program and potato improvement team are grateful for the opportunity to conduct cooper- ative and interdisciplinary research efforts across North Dakota and western Minnesota, and appreciate our many grower, industry, and research cooperators in North Dakota, Minnesota, and beyond, for funding, certified seed potatoes, encouragement, and cooperation in support of our processing research. Resulting from a cross made in 2006 between Dakota Russet and Dakota Trailblazer, the dual-purpose russet ND060735-4Russ has performed well in the National French Fry Processing Trial.