Liberator: A round white chip- processing variety with resistance to scab

Liberator is a round white chip-processing selection with medium-high specific gravity and resistance to scab (Streptomyces scabies Thaxter). The tubers will chip process out of the field and from 10 C storage. The tuber appearance is similar to Norchip. Post-harvest tuber tests indicate a tolerance to fusarium dry rot. Liberator was tested in the North Central Regional Trials and the National Snack Food Association Trials. Under irrigated conditions the yield and specific gravity are similar to Snowden and Atlantic. Liberator has a full-season vine maturity that is similar to Snowden and tuber dormancy equal to Atlantic.     

White Pearl—A chipping potato variety with high level of resistance to cold sweetening

White Pearl is a chipping cultivar with high level of resistance to cold sweetening. The cold-chipping capacity of White Pearl is better than the current chipping cultivars, including Atlantic, Snowden and NorValley. White Pearl has low glucose content and good chip color when processed directly after a 7-month storage period at 3.3 to 5.5 C. White Pearl tubers are similar to Snowden with a round oval shape, light netting, shallow eyes, white flesh, small to medium size, uniform shape, and are practically free of external and internal defects. The yield and specific gravity of White Pearl are medium. White Pearl is similar to Snowden in susceptibility to early blight, pink rot and soft rot, but it is slightly more resistant to common scab. White Pearl vines are susceptible to late blight, but can be managed effectively with fungicides. White Pearl is more sensitive to blackspot bruise than Atlantic or Snowden at 7.2 C, but is more resistant at higher temperatures. White Pearl is sensitive to metribuzin (Sencor), but not rimsulfuron (Matrix) or sulfentrazone (Spartan).     

Sentinel: An Early Yellow-Fleshed Potato Cultivar Suitable for Fresh Market and Chip Processing

Sentinel (FV8957-10) is a new yellow-fleshed potato cultivar that produces a high yield of attractive round to oval tubers at early harvest. Sentinel is suitable for fresh market use and chip processing. It was selected at the Lethbridge Research Centre of Agriculture and Agri-Food Canada, AB from a cross made at the Potato Research Centre of Agriculture and Agri-Food Canada, NB between breeding clones F72218 and F47024. Sentinel has erect medium-height vines and produces uniform tubers of medium-size with a light buff skin, light yellow flesh and shallow eyes. In multi-date-harvest trials, Sentinel produced similar or higher marketable yield compared to Atlantic and NorValley in southern Alberta. When harvested at 80 days after planting, Sentinel produced similar or greater yield than Superior and Conestoga at test sites across western Canada. Specific gravity of Sentinel was less than Atlantic and Conestoga but higher than NorValley and Superior, whereas chip colour was similar to Atlantic and lighter than NorValley or Superior. Sentinel showed little tendency to slough or to darken after cooking. It showed clear foliar and tuber symptoms when infected with bacterial ring rot. Sentinel is moderately susceptible to verticillium wilt, early blight, fusarium wilt and common scab and susceptible to late blight.     

Dakota Jewel: An attractive, new, bright red-skinned, fresh market potato cultivar with improved storage characteristics

‘Dakota Jewel’ is a medium- to late-maturing potato (Solanum tuberosum L.) cultivar; however, tuber maturity is early. Tubers are smooth, round to oblong in shape, with bright red skin and white flesh. Dakota Jewel is suitable for the fresh tablestock market, both directly from the field and following storage. Yield potential is medium, with total yield, U.S. No. 1s and percentage U.S. No. 1s of Dakota Jewel equal to those of Red Norland; size distribution is similar. Dakota Jewel sizes early, retains its color in storage, and has strong dormancy. It is susceptible to hollow heart. A mean specific gravity of 1.077 across non-irrigated and irrigated sites in North Dakota is much higher than Red Norland and Red Pontiac, standard red tablestock cultivars. Sensory evaluation scores of baked, boiled, and microwaved tubers are similar to Red Norland and Red Pontiac. Dakota Jewel was released by the North Dakota Agricultural Experiment Station on 26 March 2004.     

NorValley: A white-skinned chipping cultivar with cold-sweetening resistance

NorValley is a multi-purpose, high-yielding, whiteskinned cultivar suitable for processing into chips, dehydrated flakes, or for table stock use. It chips directly from long-term storage at 6 C without reconditioning. NorValley has wide adaptability and is suitable for production on irrigated or non-irrigated land and has a low incidence of hollow heart. NorValley was released by the North Dakota Agricultural Experiment Station on August 22,1996.     

Boulder: A round white multipurpose potato variety

Boulder is a round white selection with medium specific gravity that can be used in both the tablestock and chip-processing markets. The tubers will chip process out-of-the-field and from 10 C storage. The tubers of Boulder are large in size with a low incidence of internal defects. Boulder was tested in Michigan State University trials, the North Central Regional trials, on-farm trials in Michigan and other out-of-state replicated agronomic trials. Under irrigated conditions in Michigan, the yield is similar to or better than Atlantic, but specific gravity is less. Boulder has a full-season vine maturity that is similar to Snowden, but the tubers size early. Based upon our trials, an in-row spacing of less than 25.4 cm to reduce the percentage of oversize tubers is recommended. In simulated bruise tests, Boulder had less blackspot bruising than Atlantic, but was more blackspot susceptible than Onaway. Based upon five years of trials, Boulder has resistance to scab that is greater than Atlantic, but less than Onaway.     

Differences in sugars,chip color,specific gravity and yield of selected potato cultivars grown in michigan

Six cultivars, Atlantic, Eramosa, Kanona, Norchip, Onaway and Saginaw Gold and four selections, MS 700-70, MS 700-83 (Spartan Pearl), MS 716-15 and W-855 (Snowden), were analyzed for sucrose, glucose, chip color, specific gravity and yield at 98 and 138 days in 1988 and 1989, t evaluate their performance to Michigan growing conditions. The average yield of these cultivars at the two harvests for 1988 and 1989 was 46.9 and 54.7 t/ha and 43.1 and 52.3 t/ha, respectively. Eramosa and Onaway were the earliest maturing varieties with low specific gravity, high glucose content and processed into dark colored chips. The glucose and sucrose contents of the remaining eight cultivars at each harvest date were low and produced acceptable chips. The specific gravity of Atlantic, MS 700-70, MS 716-15 and W-855 was in the range of 1.079–1.088 and for Norchip, Kanona and Saginaw Gold the range was 1.071–1.076. The date of harvest, variety and year of production had significant effect (p > 0.01) on yield. The specific gravity, glucose content and chip color were significantly influenced by variety and year of production. The correlation between chip colorvs glucose (r= -0.842, p = 0.000) and harvest datevs yield (r= -0.572, p = 0.000) was also significant.     

Dakchip: A white-skinned chipping cultivar

North Dakota State University announces the name of a new potato to be called Dakchip. Dakchip is a medium maturing cultivar with chip quality quite comparable to Norchip but better than Kennebec. This new cultivar has round to oblong white skinned tubers and has an excellent plant type and growth. Dakchip is comparable to Kennebec in yield but higher than Norchip. Dakchip has moderate resistance to late blight but is susceptible to most potato viruses and some races of scab.     

Influence of cultivar,harvest-date and soil nitrogen on sucrose,specific gravity and storage stability of potatoes grown in Michigan

The cultivars Atlantic, Belchip, Denali, Monona, Norchip and Russet Burbank were harvested at weekly intervals from early August to early October in 1980–81 and analyzed for the following attributes: 1) sucrose rating (SR) (mg sucrose/g fresh tuber) 2) specific gravity (Sp.G.); 3) total yield and 4) chip color. At the final harvest, samples of each cultivar were stored and analyzed for color to determine chipping ability after storage. All varieties achieved a SR below 1.0 by 145 days of growth. Higher nitrogen levels reduced the total yield for early harvests but had no significant effect for later harvests. Changes in sucrose levels as tubers matured were helpful in evaluating the chemical maturity of more recently developed cultivars in relation to established chipping varieties.     

温度、pH对马铃薯多酚氧化酶活性的影响

对加工型马铃薯试管苗、茎段愈伤组织、块茎及块茎芽在不同温度、不同 pH条件下PPO活性的检测结果表明 :pH对马铃薯PPO活性具有明显的影响 ,块茎芽以及愈伤组织PPO活性均在 pH 5～ 5 5之间最高 ,分别为 94 2 0及 2 0 4 0 (0 0 1ΔOD/min) ,而试管苗在培养基 pH为 8时PPO活性最高 (19 80 (0 0 1ΔOD/min) )。不同温度下不同品种PPO活性表现不同 ,甘农薯 1号、Atlantic试管苗PPO活性在 18～ 2 5℃之间达到高峰 ,分别为 16 80和 37 2 0 (0 0 1ΔOD/min) ;Shep ody、Snowden试管苗在 5℃下PPO活性较高 ;除此之外 ,不同品种贮藏块茎PPO活性均在 2 5℃表现最高。     

Dakota rose: A bright red tablestock potato cultivar that retains its skin color in storage

‘Dakota Rose’ is a medium-maturing, white-fleshed, red-skinned cultivar that retains its bright red color in storage. Tubers have very smooth skin with an oblong shape. Yields are equivalent, or superior, to ‘Red Norland’, but lower than ‘Red Pontiac’, a late-maturing cultivar. Dakota Rose produces a high percentage of U.S. No. 1 tubers and few oversized tubers. Sensory evaluation scores for baked, boiled, and microwaved potatoes are similar to Red Norland and Red Pontiac, standard red tablestock cultivars. The specific gravity averaged about 1.067 across irrigated and non-irrigated sites, a typical value for a red tablestock cultivar. Adequate skin set for handling has often been difficult to achieve; application of nitrogen early in the growing season, coupled with chemical vinekill 3 weeks prior to harvest aids in minimizing the problem. Dakota Rose was released by the North Dakota Agricultural Experiment Station on 17 November 2000.     

Ivory Crisp: A potato variety with high tuber solids and cold chipping ability

Ivory Crisp was released in 2002 by the experiment stations of Idaho, Oregon, Washington, and North Dakota, and by the USDA/ARS. It resulted from a 1980 cross of ND292-1 and A77268-4. Ivory Crisp is suited for use in both the direct delivery and storage chipping markets. Ivory Crisp is a medium-maturing potato variety with round, white tubers and excellent chipping quality. It has medium to high yield potential, high tuber solids, resistance to most internal and external tuber defects, and the ability to chip from cold storage. In trials in Idaho, Oregon, and Washington, total and U.S. No. 1 tuber yield of Ivory Crisp was similar to Atlantic but lower than Chipeta. Yield of tubers in the size range 113–336 g for Ivory Crisp is higher than for either Atlantic or Chipeta. Ivory Crisp is resistant to growth cracks, secondary growth, hollow heart, and stem-end necrosis, but susceptible to shatter bruise. Tuber sugar content has consistently remained low following cold storage and near-acceptable chip color retained at 4.4 C. Ivory Crisp is susceptible or moderately susceptible to most common field diseases of potato. It is highly susceptible to common scab, powdery scab, and pink rot. Tubers of Ivory Crisp have dry matter content (22.4%) lower than those of Atlantic, but higher than those of Chipeta. Glycoalkaloid content of Ivory Crisp tubers is very low (4.3 mg 100 g^-1). An application for Plant Variety Protection has been filed for Ivory Crisp. Seed is available from potato seed growers in Idaho, North Dakota, and Canada. Small amounts of seed, for research purposes, can be obtained by contacting the corresponding author.     

Uniformity among virus-free clones of ten potato cultivars

Heat therapy and meristem tip propagation were used to develop two or three virus-free clones of 10 cultivars from the following sources: Epicure from British Columbia and Scotland; Katahdin, Kennebec, Keswick, Red Pontiac and Sebago from British Columbia and New Brunswick; Norchip from Alberta, Quebec and Washington; Norland from Alberta, British Columbia and North Dakota; Red La Soda from British Columbia, Nebraska and North Dakota; and White Rose from British Columbia and North Dakota. Tests prior to treatment showed that all but one of the stocks were infected with potato virus X and/or potato virus S but in only five of the ten cultivars were all clones infected with the same virus or viruses. Field trials with the virus-free clones, which extended over four years, showed that one of the Norchip clones produced fewer tubers per plant than two other clones in three years of the four years, but no consistent differences in yield or specific gravity of tubers were found among the clones of any of the 10 cultivars.     

Influence of seedpiece spacing and population on yield, internal quality, and economic performance of Atlantic, Superior, and Snowden potato varieties in eastern North Carolina

In recent stand assessment surveys on North Carolina farms, potato plant stands averaged only 67% of target populations. In response to these findings, this study was designed to determine the effects of seed-piece spacing and varying seedpiece populations on yield, internal quality, and economics of three potato varieties commonly grown in North Carolina: Atlantic; Snowden; and Superior. The three varieties responded differently to changes in spacing and population. Atlantic was sensitive to differences in spacing and populations, with reduced yields of grade A tubers as spacing increased above 23 cm. Atlantic was not able to compensate for wide (46 cm) spacing, even when seed-piece populations were high (doubles planted every 46 cm). Yield of B tubers was greater for 15 cm spacing and decreased significantly as spacing was increased. Yield of Superior was affected less by increases in spacing than decreases in population. Superior was able to compensate for wide gaps in spacing if seedpiece populations were high. Superior produced more B tubers at the 15 cm spacing, and less at the 46 cm spacing. Yield of grade A Snowden tubers did not differ with spacing or population; however, there were more B tubers in the 15 cm, 23 cm, and 46 cm (doubles) treatments than the wider spacing treatments. Incidence of hollow heart and heat necrosis increased in Atlantic in treatments that tended to have larger tubers. Economic analyses of data suggest that growers can significantly increase profit/hectare by optimizing spacing and populations with Atlantic and seedpiece populations in Superior.     

Skin set evaluation by skin shear measurements

Skin set of tubers, an indication of maturity, is a major reason for desiccating potato vines (Solanum tuberosum L.). A hand-held torque meter was evaluated for measuring tuber skin resistence to shearing as a measure of skin set. To demonstrate practical use of the torque meter to growers, shear resistance must be related to tuber skinning. ‘Atlantic’ and ‘Snowden’ potato tubers were individually measured for skin shear resistance followed by skinning. A linear relationship between skin shear resistance and tuber skinning was observed. The regression equations were Torque (mN*m) = 354 - (1.4 * Percent Skinning) for Atlantic in 1995 and Torque (mN*m) = 404 - (2.2 * Percent Skinning) for Snowden in 1996. The objective measuring of shear resistance was directly related to the more subjective measuring of tuber skinning with an R-square of 0.83. In 1995, harvested Atlantic tubers from desiccated plants were measured for skinning and resistance to torque. Skinning decreased and torque resistance increased during the 3-wk period after the initial desiccation treatment. However, skinning remained unacceptable at one and two weeks after desiccation regardless of treatment. Three weeks after desiccation, tubers from diquat-treated plots showed acceptable skin set levels and a torque resistance over 325 mN*m, which the model indicated would give acceptable skin set. Unacceptable skinning and a low torque resistance, less than 310 mN*m, remained a problem with vine flailing. Data indicated that resistance to torque exerted by the torque meter was an accurate measurement of skin set for harvested tubers. However, model regressions for the two round-white chipping cultivars, Atlantic and Snowden, differed. The torque meter can be used in the field or office. A major difficulty was maintaining a constant pressure on the tuber skin while applying the torque.     

Winema: An Early Maturing, Red- Skinned Cultivar for Fresh Market

Winema, an early maturing, red-skinned cultivar for fresh market use, was jointly released in 2000 by the Agricultural Experiment Stations of Oregon, North Dakota, California, Idaho, and Washington. Winema was evaluated in irrigated trials in Oregon and California from 1990 to 2000 and in the Western Regional Trial in 1995,1997, and 1998. Winema has produced lower total yields than Dark Red Norland and Red LaSoda at most locations, but similar or higher marketable yields and significantly fewer culls. In 20 location-years of replicated Oregon and California trials, Winema produced 108% and 99% of marketable yields of tubers under 280 g compared with Red LaSoda and Dark Red Norland, respectively. Similarly, in 23 location-years of The Western Regional Trial in 6 western states, Winema produced 109% and 92% of marketable yields of tubers under 280 g compared with Red LaSoda and Dark Red Norland, respectively. Winema tubers are smooth-skinned with shallow eyes. Winema’s bright red color does not fade appreciably in storage. Winema is susceptible to potato virus Y (PVY). Foliar symptoms of PVY are difficult to detect visually.     

Marcy: A chipping variety with resistance to common scab and the golden nematode

‘Marcy’ is a white-skinned, white-fleshed potato cultivar notable for its high yield, good chip color, and resistance to common scab and race Ro1 of the golden cyst nematode. It was selected from a cross made at Cornell University in 1990 between ‘Atlantic’ and Q155-3. Full-season marketable yields of Marcy have averaged 15% to 20% greater than Atlantic in 83 trials across New York, Maine, and Pennsylvania. Specific gravity of Marcy has averaged 0.008 less than Atlantic. Chip color out of 7 C storage in New York has been similar to ‘Pike’, but not as light as ‘Snowden’. Marcy tubers have an attractive oval shape, shallow eyes, and highly textured skin. Marcy was jointly released by the New York and Pennsylvania Agricultural Experiment Stations in 2002.     

A rapid test for chemical maturity monitoring of tubers

A rapid procedure for determining tuber maturity and processing quality using a blood glucose monitor is outlined. The procedure is simple to use, inexpensive and gives acceptable percent glucose and sucrose rating (SR) values for commercial applications. The procedure has been used successfully for determining the best time to sell commercial quantities of stored tubers (cvs. Norchip, Niska) for processing as chips in Alberta.     

Influence of potato specific gravity on yield and oil content of chips

Tubers from bulk samples of Norchip potatoes were separated into specific gravity groups by weighing each tuber in air and then in water. Forty-nine chipping samples were assembled according to specific gravity from the segregated tubers (1.060 to 1.110 specific gravity). Chip yield increased and chip oil content decreased linearly through a specific gravity of 1.110. The contribution of specific gravity to chip yield was demonstrated by expressing chip yeild on a zero percent oil basis. For all lots of Norchips tested, the specific gravity distribution was similar, and all standard deviations (s) were the same (0.0064). Using s, a table of tolerances was compiled for estimation of the appropriate sample size for routine specific gravity determinations.