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M A R C H 2 0 1 6 POTATO GROWER 13 cracksecondary growth 2 hollow heart 2 wireworm 2 and soft rot 1. In North Dakota samples were collected from 17 different red-skinned potato lots. From these samples the most prevalent blemishes were skin netting 40 and external bruisingskinning 35. Other blemished documented were superficial common scab 15 black dot 14 growth cracks 14 lenticel spot 10 silver scurf 7 enlarged lenticels 6 pink or light color 4 and vascular discoloration 3. Blemishes such as external bruise lenticel spot and sunburn can be con- trolled through cultural management practices. These data indicate growers could improve quality by taking more care when handling potatoes allowing potatoes to dry sufficiently after wash- ing and ensuring complete soil cover- age over tubers to prevent greening. The use of plant growth regulators to improve blemishes was evaluated in Becker Minnesota and Grand Forks North Dakota. In each trial plant growth regulators did not effect total yield. The use of NAA naphthale- neacetic acid Rejuvenate on seed reduced stem number at Grand Forks from 4.5 non-treated to 3.3-3.7 stemsplant. This was likely because the stem number of the non-treated was higher in Grand Forks than Becker. In Grand Forks blemishes were not affected by the growth regulators used. However in Becker ethephon 2- chloroethyl-phosphonic acid reduced nettingrusseting on tubers but increased the amount of pitted scab and lenticel spot. The use of 24-D did not increase or decrease blemishes. Trials conducted in Grand Forks North Dakota and Becker Minnesota showed that some fungicides reduced black dotsilver scurf blemishes. Those that were most consistent were Emesto Silver Quadris Nubark Mancozeb Moncot 70 DF and Maxim 4 FS Table 1. Other treatments showed promise but were not consistent as the previous- ly mentioned products. We have learned from this first year of study that blemishes were common from tubers sampled and some can be controlled by management practices. Plant growth regulators generally did not effect blemishes except in the case of ethephon. Fungicides at planting reduced blemishes in some cases. Further research is being conducted on this project and will be reported in the future.