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.     

Yield and relationships among tuber size,sucrose and chip color in six potato cultivars on various harvest dates

Cultivars were harvested biweekly for yield, weekly for sucrose determinations, and stored for chipping. At the last harvest Crystal was highest in total and marketable yield. Specific gravity was higher in Lemhi, Russet Burbank, and Norchip than in Kennebec, Crystal and Dakchip. Storage tests showed Norchip had superior chipping color to other cultivars. Dakchip had better color after short rather than after long-term storage, while the opposite was true for Kennebec and Russet Burbank. Lemhi and Crystal were marginal in color throughout storage. Sucrose (mg sucrose/g fresh tuber) expressed as a sucrose rating (SR) ranged from 1.2 to 11.9 among the various cultivars and harvest dates. Correlation between SR’s and tuber size within cultivars ranged from ?.91 to ?.97. Variability in sucrose content of immature tubers explained 70% of the variability in chip color among cultivars after storage from four to six months. Sucrose levels may be used to predict relative chipping quality of various cultivars after moderate to long-term storage if measured during early tuber development when differences in sucrose concentration are greatest among cultivars.     

Mineral and protein content,test weight,and yield variations of hard red spring wheat grain as influenced by fertilization and cultivar

Among the complex factors affecting grain nutritional quality, protein and mineral content are highly important. A two-year study was conducted in eastern North Dakota to determine the influence of fertility on the protein and mineral content, test weight, and yield of two hard red spring wheat (Triticum aestivum L.) cultivars. Zero, medium (56, 12, and 47 kg/ha), and high (280, 122, and 465 kg/ha) rates of N, P, and K, respectively, were applied in a complete factorial arrangement to ‘Era’ (a semi-dwarf) and ‘Waldron’ wheat (a tall type) in 1977. Seven of these treatments were repeated in 1978. Micronutrients and S were also applied to most treatments in 1977, and micronutrients but no S to all treatments in 1978. In 1977 on a site with high residual NO₃-N, additions of N reduced yields and test weight but increased protein, P, Ca, Zn, Mn, and Fe content. At this site application of P increased grain yield, P, K, and Mg contents but reduced protein and Zn; fertilizer K increased Mn and Fe content and reduced yield, P, K, and Mg. In 1978, N additions increased grain yield, protein, Ca, and Fe but reduced Zn. The application of P and K had little influence on the composition of the grain in 1978. The two cultivars acted the same both years, with Waldron exceeding Era grain in protein (15%), P (12%), Mg (12%), Mg (12%), Zn (17%), Mn (30%), and Fe (12%). Era surpassed Waldron in test weight (2%), K (2%), and Ca (27%). Era proved to be more responsive to fertilizer additions for most grain parameters. Drier weather conditions and lower soil N status for the 1978 experiment produced grain higher in test weight and P, K, Ca, Mg, and Fe content but lower in yield, protein, and Zn. Many highly significant fertilizer-grain and grain-grain interactions were observed. Since wheat grain composition may often be altered by fertilizers and cultivars, the range of these changes should become known through investigations by soil scientists, agronomists, and nutritionists; additional research should be conducted to determine if their changes are of nutritional significance.     

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.     

Specific gravity,potato chip color and tuber mineral content as affected by soil moisture and harvest dates

In 1966 and 1967 the chipping quality of three potato varieties was studied using three moisture regumes, two nitrogen levels, and three harvest dates. Specific gravity and chip color of potatoes freshly harvested and of those stored 10 days, along with chip color differences between the two periods, were tested. Of the three varieties tested — Anoka, Kennebec, Irish Cobbler — Anoka§ specific gravity was least depressed by soil-moisture stress and its chip color least affected by time of chipping; all tubers, however, chipped darker after being stored. High soil temperatures were associated with low specific gravities and dark chips. In 1966 irrigation tended to lower soil temperature, resulting in lighter chip color for potatoes harvested from irrigated than from nonirrigated plots; also color was lighter at the first than at the later harvests. In 1967, when air temperatures were consistently lower and rainfall nearly adequate, chip color was lighter for potatoes harvester later in the season. Nitrogen levels did not influence chip color. Moisture regimes and varieties influenced mineral content of tubers more consistently for the two years than did harvest dates or nitrogen levels. Specific gravity did not correlate significantly with chip color.     

Effects of cement kiln dust on soil and potato crop quality

Cement kiln dust is a potential source of K and Ca for crops on acidic soils in Eastern Canada. The objective of this study was to assess the effect of cement kiln dust on soil chemical properties and potato (Solanum tuberosum L. cv. Superior) yield and quality on two Spodosols. Four rates of cement kiln dust, commercial K fertilizers, and lime were yearly applied and arranged in a randomized complete block design with four replicates. Soil extractable K and Ca increased rapidly after cement kiln dust applications and were comparable to commercial fertilizers or lime treatments. Heavy metal soil contents and plant uptake were not influenced by treatments. Soil metal contents decreased from to initial soil levels and were lower than recommended maximal norms. Tuber yields increased with rates of cement kiln dust and commercial fertilizers but decreased with lime rates. Yields were positively correlated to soil extractable K and partially with extractable Mg. The K and Mg plant uptake increased with cement kiln dust and commercial fertilizers rates but was significantly reduced by liming. Tuber specific gravity decreased with the highest commercial fertilizers and cement kiln dust rates. These results showed that cement kiln dust is an effective source of K and Ca for potato production without short term loss in tuber quality or soil contamination by metals.     

Potato chip color,specific gravity and fertilization of potatoes with N−P−K

The effects of fertilizers on potato chip color were studied over a period of 11 years. Yield and specific gravity data also were taken. Single element and compete fertilizers were used in randomized block and split plot experiments. Most of the work was done with the Russet Burbank variety but in some experiments the Kennebec, White Rose, Norgold Russet and Cascade varieties were also included. Specific gravity and chip color data were taken immediately after harvest. Effects of storage and reconditioning on chip color were recorded in some cases. Though statistically significant effects of N?P?K on chip color were found, the differences were small and of no commercial importance. Neither nutrient balance nor total amount of fertilizer used greatly affected chip color whether the tubers were harvested “immature” in July or in October after the vines were dead. The greatest effect of over-fertilization was on the specific gravity of the tubers. As amount of fertilizer applied increased, specific gravity often decreased which would reduce the amount of processed product per unit of fresh produce. Since most manufacturers of processed potatoes prefer high specific gravity tubers perhaps varieties should be grown specifically for the processing industry. Since proper fertilization did not have a commercially important effect on chip color but greatly increased the yield, farmers should fertilize for maximum production when growing potatoes for potato chips.     

氮磷钾肥对稻米铁、锌、铜、锰、镁、钙含量和产量的影响

 采用田间试验，在四川省西昌市用两个水稻品种研究了氮、磷、钾肥施用量对稻米中铁、锌、铜、锰、镁、钙含量和产量的影响。结果表明，稻米中铁、锌、铜、锰、镁、钙含量均随着施氮量增加先上升后下降，滇屯502的铁、锌、铜、锰、镁、钙含量和产量都以施用90 kg/hm2 N最高，稻谷产量以施用180 kg/hm2 N最高；而合系39的铁、锌、铜、锰、镁、钙的含量以施用180 kg/hm2 N最高，稻谷产量以施用270 kg/hm2 N最高，说明供试籼型品种滇屯502对氮肥的敏感性较粳型品种合系39强；磷肥明显降低了稻米中铁、铜、锰、钙的含量和产量，适量增施磷肥有利于增加稻米中镁的含量和产量；适量施用钾肥有利于提高稻米中铁、锌、铜、锰含量和产量，两供试品种铁、锌、铜、锰含量均以90 kg/hm2 K2O时最高，而钾肥明显降低了稻米中镁、钙的含量和产量。     

尿素和茶树落叶对荒地土壤元素迁移的影响

用亚热带茶区的3 种未垦荒地土壤进行土柱模拟, 研究重施尿素和表覆茶树落叶对土壤中Si、Al、K、Na、Ca、Mg 等6 种元素迁移的影响。结果表明, Si 的淋出量和Al+ K+ Na + Ca +Mg 的淋出总量均以黄棕壤> 红壤> 赤红壤。尿素和茶树落叶处理对硅淋出量的影响较小, 但可使各土壤主要的淋失元素, 包括赤红壤中的Ca 和Na, 红壤中的Ca 和Al 及黄棕壤中的Na、Ca和Mg 的淋失量明显增大, 从而使Al+ K+ Na+ Ca+ Mg 的淋出总量在3 种土壤中分别比对照柱增加163 % 和58% 、64 % 和57 % 、140 % 和84 % , 尿素的促进盐基和Al 淋失作用比茶树落叶更强,两者都可加速土壤的酸化。     

Tuber yield, storability, and quality of Michigan cultivars in response to nitrogen management and seedpiece spacing

Information is required on nitrogen (N) fertility and seedpiece management for new cultivars and advanced breeding lines. Interactions amongst N fertilizer rate, genotype, and seedpiece spacing are complex, and can affect tuber yield, quality, and storability as well as N fertilizer efficiency. A field study was carried out in 2001 and 2002 at MSU Montcalm Research Farm in central Michigan. Tuber yields and post-harvest quality characteristics were evaluated for five potato genotypes (MSG227-2, MSE192-8Rus, Jacqueline Lee, Liberator, and Snowden) in response to a factorial combination of three N levels (200 kg N ha^-1, 300 kg N ha^-1-, and 400 kg N ha^-1) and two seedpiece spacings, narrow (0.20 m or 0.25 m) and wide (0.33 m or 0.38 m). Narrow seedpiece spacing consistently produced the highest U.S. No. 1 yields in all genotypes tested (37 and 34 t ha^-1, narrow vs wide spacing, respectively). There was a tradeoff between seedpiece spacing and N level in 2001 as tuber yields were enhanced by higher N levels at wide seedpiece spacing, but not at narrow spacing. In 2002, tuber yield was not enhanced, but petiole nitrate-N and tuber-N increased as N fertilization increased. Genotype was the major factor that influenced tuber quality characteristics at harvest and for stored tubers (e.g., specific gravity, internal defects, bruising, chip color rating, sucrose, and glucose). Spacing had minimal effects, whereas higher levels of N slightly reduced specific gravity both years, reduced internal defects in 2001 and enhanced sucrose at harvest in 2002. The cultivars tested demonstrated excellent storage characteristics for different N fertility levels and seedpiece spacing combinations. Overall, the recommended N fertilizer level for moderately long-duration potato cultivars in Michigan (200 kg N ha^-1) and a narrow seedpiece spacing optimized yield and tuber quality performance while conserving N fertilizer.     

Growth,Yield and Quality of Turmeric (Curcuma longa L.) Cultivated on Dark-red Soil,Gray Soil and Red Soil in Okinawa,Japan

Abstract

We evaluated growth, yield and quality of turmeric (Curcuma longa L.) cultivated in pots with dark-red soil (pH 5.2), gray soil (pH 7.4) and red soil (pH 4.4) in Okinawa, Japan. The soils were collected from the 50-cm deep layer of the fields. We did not use any chemicals or organic fertilizers. Turmeric cultivated on dark-red soil had the highest plant height, root biomass and shoot biomass as compared with that cultivated on other soil types. Turmeric on dark-red soil had the highest yield with favorable color of the deep yellow and high curcumin content (0.20%). Protein content of turmeric in dark-red soil was 5.2%, which was around 40% higher than that in other soil types. Turmeric cultivated on dark-red and gray soils had a fat content 71% higher than that in red soil. The content of Ca, K and Mg was the highest when turmeric was cultivated on gray soil, and Fe was the highest when cultivated on dark-red soil. To gain a high yield and high contents of curcumin, fat, protein and Fe, we should cultivate turmeric in dark-red soil in Okinawa. We could not recognize the specific soil factor(s) required for high yielding and high quality of turmeric; however, it seems that a proper combination of soil factors, nutrients and/or pH level may be necessary to gain a high yield and high quality.     

不同品种椰子液体胚乳发育过程中K、Ca、Na、Mg元素变化规律

对3个不同品种椰子液体胚乳中K、Ca、Na、Mg等4种大量矿质营养元素含量的动态变化规律,以及不同果龄及不同品种间的元素含量进行比较和相关性分析。结果表明,椰子果实在发育期间,随着果实的发育椰子液体胚乳中的K、Ca含量呈逐渐下降、Na含量呈逐渐增加、Mg含量呈逐渐下降之后回升的趋势。所测4种元素含量,K>Ca>Mg>Na。不同元素含量在不同品种间的比较结果不同,K含量中,本地高种>小黄椰>文椰3号;Ca含量中,文椰3号>小黄椰>本地高种;Na含量中,小黄椰>本地高种>文椰3号;Mg含量在第7串果实中,本地     

云南澳洲坚果园土壤和叶片养分评价

通过对云南省西双版纳、普洱、临沧、保山、德宏等5个具有地域代表性的澳洲坚果种植区中的土壤和叶片养分分析,发现澳洲坚果种植区土壤与叶片养分具有较大的地域差异。47个澳洲坚果园的土壤pH、有机质和碱解氮、有效磷、速效钾、交换性钙、交换性镁、有效硼、有效铜、有效锌平均含量分别为：4.94、29.17g/kg和109.23、36.64、200.05、352.78、85.65、0.60、2.03、2.14 mg/kg;叶片氮、磷、钾、钙、镁和硼、铜、锌平均含量分别为：16.36、0.73、8.39、6.05、0.80 g/kg和17.74、3.46、9.86 mg/kg。土壤pH值低于5.0的样品比例占60%,土壤有机质、碱解氮、有效磷、速效钾、有效铜和有效锌含量达到丰富程度的样品比例依次分别占40%、31%、47%、56%、38%和18%,土壤交换性钙、交换性镁和有效硼达到缺乏程度的样品比例依次为71%、67%和84%。叶片氮、磷、钾、钙、镁和锌养分达到适宜和丰富的样品比例为97%、67%、100%、49%、51%和100%,磷、钙、镁、硼和铜养分达到缺乏程度的样品比例依次为33%、51%、49%、87%和88%。因此,云南澳洲坚果园土壤肥力调控的重点是增施有机肥,减施磷钾肥,补施钙镁中量元素及铜硼等微量元素。     

Irrigation,nitrogen and gypsum effects on specific gravity and internal defects of Atlantic potatoes

Irrigation, nitrogen and gypsum were investigated in a 3-year study to determine their influence on specific gravity and internal physiological defects. Excess irrigation during August and September reduced specific gravity, increased the incidence of hollow heart, and in some years, internal brown spot. Tuber yields were not significantly affected by excess irrigation. Exclusion of late season irrigation, however, significantly reduced tuber yields. No consistent yield response to nitrogen was evident, but a response up to 168 kg/ha was observed in 1987. Nitrogen rate did not effect hollow heart, internal brown spot or chip color. The incidence of internal brown spot in the tubers of check treatments was quite variable from year to year, and ranged from 8 to 21%. The lowest incidence of internal brown spot observed in 1989 coincided with the highest calcium levels in the tuber peel. Although gypsum treated potatoes had reduced incidence of internal brown spot, the effects were partial and inconsistent. Significant increases in peel and petiole calcium concentrations in the gypsum treated plots only occurred in one year. The peel calcium levels appeared to be influenced more by the season and to a lesser extent by gypsum. Gypsum applications produced no effects on total or US#1 tuber yield, specific gravity, hollow heart, or chip color. Preliminary data also suggested that gypsum did not markedly influence the incidence of blackspot. Based on this study, a routine gypsum application to improve the tuber quality of the variety Atlantic is not recommended.     

The influence of potassium fertilizer application on tuber yield and mineral element content of potato petioles during the growing season

Potassium was applied at rates equivalent to 0, 135, and 250 pounds per acre (0, 151, 180 kg K/ha) to study the effect of soil applied K on tuber yields and concentration of mineral elements in the petioles of potato plants during growth both measured at 14 day intervals. Petioles were analyzed for N, P, K, Ca, Fe, Mg, Zn, Cu, Al, Mn, and B. Seasonal trends in petiolar K content were highly correlated with tuber bulking regardless of rate of K application. Increasing K application rates generally increased petiolar levels of K and Zn (early in the season) and decreased the levels of N, Mg, Ca, Zn (late in the season), Al, Fe, Cu, and B in the petioles. Concentrations of P and Mn were unaffected by K applications. Seasonal trends in the mineral element content of petioles were not influenced by K. Results indicate that a prediction model for tuber yield based upon trends in the K content of petioles is valid under differing soil levels of K.     

Selection for chip quality and specific gravity of potato clones: possibilities for early generation selection

Summary Ten cultivars contrasting in chip quality were grown in the field and in the glasshouse to evaluate three different methods for chip quality assessment. Specific gravity was also measured. The glasshouse culture simulated growth of seedlings and the field culture represented growth of advanced breeding lines. Differences between cultivars for chip quality and specific gravity could be established in both environments. Although ranking of the cultivars in both environments was not identical, both good and bad genotypes could be identified. It seems that mild selection for specific gravity and chip quality among glasshouse-grown seedlings can be exercised. If tubers of glasshouse-grown plants are too small to slice chips, Reflocheck Glucose test strips offer a satisfactory alternative to frying chips. Crip in UK     

Uptake and use efficiency of N, P, K, Ca and Al by Al-sensitive and Al-tolerant cultivars of wheat under a wide range of soil Al concentrations

The impacts of acidic soils and Al toxicity on wheat nutrient economy have been scarcely researched under field conditions even though these soils are widely spread in wheat production areas around the world. The main objective of this study was to quantitatively evaluate the element (N, P, K, Ca and Al) economy of an Al-sensitive and an Al-tolerant wheat cultivar growing under different soil Al concentrations at field conditions. To reach this objective, two field experiments were conducted in an Andisol in Valdivia (39°47′18″S, 73°14′05″W), Chile. Treatments were a factorial arrangement of: (i) two spring wheat cultivars (Al-sensitive, Domo.INIA and Al-tolerant, Dalcahue.INIA) and (ii) five exchangeable Al levels (0-2.7 cmol₍₊₎ kg⁻¹) with three replicates. At harvest, plant biomass was sampled and divided into 5 organ categories: ears, grains, blade leaves, stems plus sheath leaves and roots. The element content (N, P, K, Ca and Al) in each organ was measured to quantify element uptake and concentration, nutrient uptake efficiency (UPE) and nutrient utilization efficiency (UTE). Element uptake (N, P, K, Ca, and Al) was negatively affected by the increased soil Al concentration in above-ground and root biomass in both cultivars (R² = 0.61-0.98, p < 0.01), although clear differences were found between cultivars. On the contrary, the impact of soil exchangeable Al on the plant element concentration was minor, showing weak associations with soil Al levels. However, the Al concentration in above-ground tissues of the Al-sensitive cultivar was an exception because it increased exponentially with the Al soil concentration (R² = 0.96-0.99, p < 0.001). Nutrient uptake efficiencies, UPEs (N, P, K and Ca), were negatively affected by soil Al concentrations and were well described by linear equations in both cultivars (R² = 0.58-0.98, p < 0.05), with notable differences between them. Both nutrient uptake (capture) and UPE were the traits that best explained above-ground biomass production (R² = 0.82-0.99, p < 0.001, n = 20). Nutrient utilization efficiency, UTEs (N, P, K and Ca) responded more conservatively to the soil Al concentration, except for the Al sensitive cultivar under very high soil Al levels.     

Effect of irrigation applied at different growth stages and length of irrigation period on quality characters of potato tubers

Summary Potatoes were irrigated at three growth stages: (1) planting-stolon initiation. (2) stolon initiation-tuber bulking, and (3) tuber bulking, when available soil water dropped to 25%, 50% and 75%, bringing it up to field capacity; and irrigation ceased 0, 10 and 20 days before maturity. Significant increases in specific gravity, dry matter, starch content, chip yield and significant decreases in protein content and oil absorption rate of chips were observed due to the frequent irrigation at growth stages 1 and 2. No significant effect on chip colour was attributed to irrigation during the early growth stages. Frequent irrigations at the final growth stage were found to have deleterious effects on specific gravity, dry matter, starch content and chip yield especially when irrigation continued until maturity.     

Variance components for yield and specific gravity in a diploid potato population after two cycles of recurrent selection

The potato(Solanum tuberosum L.) processing industry needs cultivars with high tuber specific gravity and acceptable color of processed product. All of the cultivars with high specific gravity currently grown in the U.S. are very closely related, which increases their genetic vulnerability and results in inbreeding as efforts are made to improve these traits. The use of diploidSolanum sp. in breeding may resolve these problems. The purposes of this study were (1) to estimate narrow-sense heritability for yield and specific gravity in random-mating diploid hybrid potato populations ofS. phureja - S. stenotomum (PHU-STN) following two cycles of recurrent selection, (2) to examine phenotypic variances for yield and specific gravity following two cycles of recurrent selection within PHU-STN, (3) to compare the yield and specific gravity of individual PHU-STN clones with Atlantic, and (4) to screen these PHU-STN clones for the presence of 2n pollen. Four clones from each of 72 maternal half-sib families were evaluated for yield and specific gravity in replicated field tests in 1990 and 1991. A second selection cycle, using a randomly mated population obtained from the highest specific gravity clone in each maternal half-sib family, was similarly evaluated for yield and specific gravity in replicated field tests in 1995 and 1996. Narrow-sense heritability for specific gravity was estimated as 0.37 ± 0.25 and 0.43 ± 0.27, in the first and second selection cycles, respectively, with a 27% decrease in phenotypic variance. Narrow-sense heritability for yield was estimated as 0.60 ± 0.26 and 0.06 ± 0.24, in the first and second selection cycles, respectively, with a 73% decrease in phenotypic variance. There were significant correlations between yield and specific gravity in 1990 (r=0.32) and 1996 (r=0.37), but not 1991 (r=0.08) and 1995 (r=0.05). These results indicate that additional breeding efforts in this PHU-STN population could result in improvements in specific gravity. However, the amount of variation for yield in this population is decreasing and may indicate that the yield potential of this population is rapidly approaching its limit. In the second selection cycle, many of the 288 clones were significantly higher in specific gravity than the high-specific-gravity cultivar Atlantic, but none were higher yielding. Fifty-eight clones from the second selection cycle produced at least 5% 2n pollen. When used in tetraploid x diploid hybridizations, this diploid population could furnish new genetic material to the tetraploid potato germplasm base for simultaneously increasing specific gravity and yield.     

Breeding progress for potato chip quality in North American cultivars

Forty-four potato cultivars, released in the period between 1876 and the present were grown concurrently in field trials, stored simultaneously in three different environments, then evaluated for chip quality. They represented cultivars historically used and/or bred for potato chip production. Quality factors measured were tuber solids, chip color, reducing sugar levels, sucrose levels, and percent of defect-free chips. Tuber solids tended to increase in the late period cultivars, but trends were erratic. The release of Lenape marked the beginning of an increase in tuber solids that has continued to the present. There was a significant trend for lower reducing sugars and better chip color that corresponded to increasingly later cultivar release dates. Since about 1960, progress toward lower reducing sugars and better chip color has been constant, regardless of whether tubers were stored at 4.4 C, stored at 4.4 C and reconditioned, or stored at 10 C. Late period cultivars tended to have a greater percentage of defect-free chips in comparison to those released earlier, with most of the improvement coming during the last few years. This study provided evidence that potato breeders have made significant progress in developing cultivars with good chip quality. Evidence was also found that Lenape was a landmark cultivar and has been an important contributor to the observed breeding progress