Caribe: A smooth,oblong, purple-skinned potato variety of early maturity

Caribe produces smooth, oblong, purple-skinned tubers of excellent type and appearance. This cultivar is early in sizing and maturity and produces tubers of good boiling quality when harvested 80 days after planting. It is well adapted to Atlantic Canada where it has potential in early and maincrop table markets and it has also shown potential in several off-shore potatoproducing countries.     

Jacqueline Lee: A late-blight-resistant tablestock variety

Jacqueline Lee has a bright golden skin, yellow flesh, attractive oval shape, and excellent cooking qualities that make it suitable for tablestock use. In addition, it has been determined to have a high level of foliar resistance to the US-8 genotype ofPhytophthora infestans (Mont.) de Bary under Michigan field and greenhouse conditions. It is a full-season variety with vine maturity similar to Snowden. Jacqueline Lee has high yield potential. It has a high set (14–16 tubers/hill) of medium sized tubers that leads to 65%–80% marketable yield. Tubers are low in internal and external defects. It has a scab reaction similar to Atlantic, and the tubers have been observed to have a long dormancy.     

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.     

Beacon Chipper: A round white chip-processing potato variety

‘Beacon Chipper’ is a high-yielding, round white potato for the chip-processing market. This variety has an attractive round appearance with shallow eyes and high percentage of oversize tubers. Specific gravity in Michigan ranges from 1.077 to 1.083. Beacon Chipper may fit a window in raw product requirements between out-of-the-field ‘Atlantic’ crop and a late storage crop. This variety has some tolerance to common scab (Steptomyces scabies Thaxter) in comparison to Atlantic and ‘Snowden’. Beacon Chipper also has good chip-processing storage characteristics (light color and low amount of defects) and better tolerance to pressure bruise than Snowden. Based upon nitrogen and spacing management studies, we recommend that Beacon Chipper be planted at 20-cm within-row spacing with 180 lbs N/acre to maximize U.S. No. 1 yield and quality. The origin and pedigree of Beacon Chipper is currently unknown, despite extensive fingerprint analyses. The name Beacon Chipper was chosen to reflect the common nautical theme of Michigan and Maine.     

Auxin Modulates Gibberellin-Induced Effects on Growth,Yield, and Raw Product Recovery for Frozen Processing in Potato (<Emphasis Type="Italic">Solanum tuberosum</Emphasis> L.)

Tuber shape phenotype is an important determinant of raw product (≥7.6-cm-long French fries) recovery for frozen processing. Tuber length-to-width (L/W) ratios ≥1.8 translate to maximum yield of raw product; however, some cultivars produce tubers with much lower L/W ratios. While gibberellin (GA) can be used to elongate tubers, it also decreases tuber size and can thereby attenuate raw product recovery. We investigated the utility of GA and naphthaleneacetic acid (NAA) combination treatments for modifying tuber set, size, and shape to increase yield of raw product from ‘Payette Russet’ and ‘Alturas’; two late-season frozen-processing cultivars that often produce tubers with undesirably low L/W ratios. Models describing L/W ratio and fry yield by tuber size class were developed to translate total U.S. No. 1 tuber yields (>113 g) into yield of raw product. Increases in the L/W ratios of 113–284-g tubers had a greater effect on recovery of French fries (% fresh wt) than for tubers >284 g. Undersize (<113 g) and oversize (>340 g) tubers yielded 0 and 96% fries, respectively, regardless of L/W ratio. GA applied as a seed treatment effectively hastened emergence and altered tuber shape by increasing the L/W ratios of ‘Alturas’ and ‘Payette Russet’ tubers, enhancing total fry yield for the 113–340-g tubers by 24–46%, depending on concentration and application technique (dip, spray, in-furrow). However, GA also decreased apical dominance and shifted tuber size distribution away from >284-g tubers toward higher yields of <170-g tubers, erasing the gains in fry yield when all size classes (>113 g) were considered. When combined with GA, NAA maintained apical dominance, attenuated the shift in tuber size distribution, had no effect on the GA-induced increase in tuber L/W ratio, and only partly moderated the GA-induced stimulation of plant emergence. Raw product yield from ‘Payette Russet’ increased 12–39% in spray application trials by using NAA to confine the effect of GA to tuber shape and limit the loss of U.S. No. 1 tubers to undersize. Increases in tuber L/W ratio with GA/NAA seed treatments translated to increased yield of fries only when the relative concentrations were adjusted to minimize loss of >284-g tubers and gain in undersize tubers, as dictated by cultivar sensitivity to GA. ‘Alturas’ was less sensitive to GA than ‘Payette Russet’ for shifts in tuber size distribution but not shape, resulting in 17% increase in raw product with GA alone in pre-plant seed spray application studies. GA/NAA combination treatments provide an effective approach to manipulate tuber size distribution and enhance the yield of raw product for frozen processing in cultivars with a rounder tuber shape phenotype.     

AC Stampede Russet: A high-yielding oblong russet cultivar for the french fry and fresh market industries

AC Stampede Russet has a maincrop maturity, and the tubers reach maximum size in western Canada in early to mid-September. The tubers are attractive with russet skin, shallow eyes, an oblong shape, and are very uniform in size. The cultivar is suitable for french fry or fresh market (count carton) production. It appears to perform best under irrigated conditions. The cultivar provides the industry with a russet-skinned, dual purpose russet cultivar with high yield, low defect levels, excellent fresh market appeal, and good storage quality for both the french fry and fresh market industries.     

Influence of Growth Regulators on Plant Growth, Yield, and Skin Color of Specialty Potatoes

2,4-D has been used since the 1950’s to enhance color in red-skinned potatoes, but there is little research on the potential use of other plant growth regulators to improve tuber skin color in the wide range of specialty potatoes now available on the market. Field trials conducted at Parma, ID in 2009 and 2010 evaluated the effect of foliar applications of 2,4-D, NAA, and LPE on plant height, foliar injury, tuber yield, size distribution, and skin color of six specialty potato cultivars. Skin color was rated visually and via HunterLab colorimeter at harvest, and again after storage (132 days in 2009 and 93 days in 2010) at 4 °C and 95 % R.H. 2,4-D caused slight foliar injury and reduced tuber size in all cultivars. It also increased visual skin color rating in the red-skinned cultivars ‘Red LaSoda’ and ‘TerraRosa’ at harvest and after storage, and influenced incidence of pink coloration around the eyes of ‘Yukon Gem’ tubers, but did not affect color of blue/purple-skinned cultivars. NAA and LPE did not consistently influence plant growth, yield, tuber size or visual skin color in any cultivar. Colorimetric evaluations mostly agreed with the visual ratings, and indicated that storage significantly altered skin color in all cultivars, regardless of growth regulator treatment.     

Optimization of Hairy Root Induction in <Emphasis Type="Italic">Solanum tuberosum</Emphasis>

An efficient protocol for hairy root induction in Solanum tuberosum was established using Agrobacterium rhizogenes. Transformation of Desiree was more efficient than with Shepody or Purple Majesty. Transformation efficiency of Desiree tuber discs (97% transformation efficiency) was higher in comparison to root (67% transformation efficiency), stem (61% transformation efficiency) and leaf (14% transformation efficiency) explants. Bacterial density, culture parameters, explant type, and genotype influenced the transformation efficiency, as well as the growth of hairy roots. Hairy root transformation efficiency in explants treated with acetosyringone was enhanced from 72 to 89% in Purple Majesty tubers and 56 to 80% in roots during co-cultivation. The growth rate of hairy roots from tuber discs was about 5 times greater than that of hairy roots from leaves. Tuber hairy roots were highly resistant to kanamycin in the absence of NPT II. This study describes the efficient generation of hairy roots in different potato tissues and cultivars that can provide a fast method to generate transformed tissue or be used for production of secondary metabolites.     

Comparative field performance of potatoes from seedlings and tubers

A field trial was conducted at Freeville, NY to compare yields from hybrid families ofSolanum tuberosum L. with yields from their corresponding full sib, first clonal generation tubers. Unselected tubers were saved after harvesting transplanted seedlings of four Neo-Tuberosum × Tuberosum hybrids in 1982. The following year these tubers were planted for comparison with seedlings of the same hybrids in a split plot design. Total yields and yields of tubers ≥ 38 mm in diameter were respectively 34% and 38% higher from tuber propagated plants than from seedlings. The biggest difference was in tubers ≥ 63 mm diameter, where plants from tubers gave yields more than double those from seedlings. Seedlings had twice as many large axillary branches per stem as plants from tubers. Uniformity of tuber size and shape, and overall appearance ratings of tubers were better with seedling propagation; however, these comparisons are biased by the tendency of seedlings to produce smaller tubers, which inherently receive higher ratings.     

Three-dimensional Stochastic Shape Modelling for Potato Tubers

Tuber shape is a genetically determined, important varietal characteristic that is also influenced by environmental factors. In this study, the overall dimensions of tubers of two potato cultivars (Van Gogh and Yukon Gold) were determined using a triaxial ellipsoid model that was found to encompass the main varietal differences. The more detailed surface features were captured using a spherical-harmonics series representation for the residual undulation. The method was then applied to four additional cultivars (Bellona, Lady Rosetta, Pito, and Sabina). Modelling the undulation of tuber surface in addition to the overall dimensions indicated that cultivars differed in the global shape and, in specific cases, also in the surface undulation of tubers. The new, improved method for modelling tuber shapes can thus capture and distinguish the overall three-dimensional shape and irregularities caused by growth conditions and other factors. It is envisaged to be useful for quantitative genetics approaches aiming to resolve the relative impact of different genes on tuber shape, as well as for various machine vision and other applications.     

Influence of time of application of maleic hydrazide on the yield and quality of Russet Burbank potatoes

A three-year study in central Wisconsin with timed foliar applications of maleic hydrazide at 3 lb/A (3.36 kg/ha) resulted in an improvement in quality and a favorable alteration in the shape of tubers of the Russet Burbank potato variety. Application in early and mid-July resulted in an increase in yield of U.S. 1 tubers and reduced yield of malformed tubers. Over 40 percent fewer misshapen tubers were produced when applications of maleic hydrazide were made during July when compared with tubers from untreated plants. Applications made in midor late July resulted in tuber development with a more favorable length to diameter ratio of U. S. 1 tubers, again compared with tubers from untreated plants. Maleic hydrazide applied in early or mid-June resulted in severely reduced yield and increased incidence of misshapen tubers. When applied in July or early August, no effect on tuber specific gravity was found. Maleic hydrazide functioned as an effective sprout inhibitor on tubers from all treatment dates except when applied in early June.     

Yield-enhancing and tuber-downsizing effects of transplantation cultivation method of case-held tuber seedlings in the sweet potato cultivar Beniharuka

We developed transplantation cultivation method of case-held tuber seedlings (CTS), which was derived from direct planting method of seed tubers, and applied this method to the sweet potato cultivar Beniharuka. A plastic case made of polypropylene was designed for cultivation of CTS. Seed tubers of cultivar Beniharuka in the range of 30–80 g were cut in half. The half-cut tubers were placed inside the plastic cases, and the cases were filled with a commercial soil mix. The case-held tubers were incubated under natural sunlight in a glass house. After 3–4 wk, the CTS were transplanted into a field. Mother tuber (seed tuber) enlargement was suppressed by the plastic confinement of the cases, and daughter tubers were formed above the case as vine-root-originated tubers. In the field experiments in 2012 and 2013, daughter tuber yields were increased 19% and 21% by case-held tuber seedling transplanting (CTST) over conventional vine-planting (VP), the number of daughter tubers per plant in CTST were 36 and 68% higher than in VP, and the mother tuber yields were limited to 2.1 and 4.3% of the total fresh yield of mother and daughter tubers, respectively in 2012 and 2013. Application of CTST method to cultivar Beniharuka enhanced tuber yield, increased the number of daughter tubers per plant, downsized daughter tubers compared to VP, and mother tuber enlargement was suppressed by case-holding. The CTST method is expected to produce more and smaller good in shape tubers of cultivar Beniharuka compared to VP.     

Influence of Foliar-Applied Growth Retardants on Russet Burbank Potato Tuber Production

The potato cv Russet Burbank grows poorly in the semi-arid climate of the High Plains, primarily due to its tendency to produce misshaped tubers. Since gibberellic acid (GA₃) is associated with stem elongation and may be involved in tuber shape, the objective of this study was to determine whether GA₃ biosynthesis inhibitors could improve tuber shape. Prohexadione-Ca and chlormequat-Cl are two well-known such inhibitors. They were applied to ‘Russet Burbank’ at 0, 70, 280, 1,120, 4,480 g/ha when the largest tubers were 20, 60 and 100 g/tuber from 2001 to 2003. Neither compound affected tuber shape. Yields increased 17–20 % by prohexadione-Ca at 280 g/ha and 9–33 % by chlormequat-Cl at 4,480 g/ha. In 2004, prohexadione-Ca at 280 g/ha was applied when the largest tubers were 3, 25, 100, 180, and 370 g to determine a tuber stage response. Yield increased 14 % when applied at 25 and 100 g/tuber growth stages, but the number of misshaped tubers increased from 48 % to 75 %. These two inhibitors did not overcome tuber misshaping and should not be used for that purpose.     

马铃薯新型栽培种在实生种子选育中的应用研究

本文研究比较了马铃薯实生种子选育中,新型栽培种(Neo-tuberosum)利用的6类不同组合方式产生的杂种实生种子在群体生产力和一致性上表现的差异,结果表明:①不同组合方式形成的具有不同Neo-tubersum基因频率的实生种子,群体间生产力表现极显著的差异。这一差异主要表现在产量构成因素上,商品薯数量和小薯数量对构成群体产量均有极显著的作用;小薯数量的增加对提高群体的商品薯率有极显著的负作用,即块茎数量越多,块茎越小。后代商品薯率取决于S.tuberosum种质,而块茎数量主要由Neo-tuberosum决定,并找出其生产力表现的优先顺序。②S.tuberosum×Neo-tuberosum组合表现的一致性水平在株高、薯形、皮色和芽眼深浅等性状上与S.tuberosum自交群体相似,没有显著差异,是利用新型栽培种进行实生种子选育的最佳组合方式。     

Variability of Phytonutrient Content of Potato in Relation to Growing Location and Cooking Method

Potato has a defined complement of metabolites that contribute to the human diet. Among these are the carotenoids and anthocyanins. Carotenoids are found in all potatoes in the flesh. White-fleshed varieties have 50 to 100 μg per 100 g fresh weight (FW), while moderately yellow-fleshed varieties will generally possess from 100 to 350 μg per 100 g FW. The more intensely yellow-fleshed genotypes, which may look orange, at the higher extremes are at levels above 1,000 μg per 100 g FW. The highest level published is 2,600 μg per 100 g FW in diploid germplasm derived from South American Papa Amarilla cultivars. Potato generally has predominantly lutein, a xanthophyll which is also found in the human retina, and must be obtained in the diet. The genotypes with extremely high levels of total carotenoids have zeaxanthin, an isomer of lutein, which is also present in the human retina. Anthocyanins are present in red- or purple-skinned and fleshed varieties. Total anthocyanins range from 1.5 mg to 48 mg per 100 g FW in a solidly pigmented purple-skinned, purple-fleshed breeding line. The degree of pigmentation in the flesh appears to be under polygenic control. Anthocyanins are potent antioxidants and anti-inflammatory substances. The level of total anthocyanins is correlated with antioxidant level (r?=?0.94, P?<?0.001). Several methods of cooking interacted with genotypes in the antioxidant level remaining after cooking compared to raw potatoes. No method of cooking completely eliminated antioxidant activity, while boiling appeared to increase it compared to raw potato in the case of the most highly pigmented clone.     

Growth and preharvest stress and processing quality of potatoes

The quality factors influenced by stress conditions are: total dry matter or starch content and distribution of starch, sugar content, types of sugars and distribution, texture, mealiness, flesh color, tuber size and shape, and tuber defects such as growth cracks, and hollow heart. Early stress during growth can cause tubers to become pointed on the stem-end with low starch content and high reducing sugars. Uneven growth due to stress results in growth cracks, or hollow heart and malformed tubers. Varieties differ considerably as to susceptibility. Stress generally causes lower starch content in tubers which results in greater sugar accumulation in storage. Relative maturity is also influenced by stress during growth. Immature and over-mature tubers (from prematurely dead plants) accumulate greater amounts of sugar in storage than tubers properly matured. Stress can also cause poor texture of processed products, such as tough texture of French fries as well as lack of mealiness. Flavor and color of processed products can also be detrimentally influenced by stress.     

Reeves kingpin: A high-yielding mid-season potato variety suitable for fry processing

Reeves Kingpin is a mid-season processing potato variety developed and selected at the University of Maine’s Aroostook Research Farm in Presque Isle, Maine. Its main attribute is its high-yielding potential, giving an average yield of 47 mt/ha. Reeves Kingpin is suitable for processing into french fries due to its large tubers, high specific gravity, and acceptable fry color. The average specific gravity of Reeves Kingpin is 1.085 which is comparable or better than ‘Russet Burbank’ and ‘Shepody’. Reeves Kingpin has received good baking scores, which may qualify it for fresh market; however, its tuber appearance generally does not meet fresh market standard. The tubers have netted to lightly russeted skin and are long and blocky in shape. The tubers rarely exhibit the pointed and knobby characteristics of Russet Burbank. The incidence of misshapen tubers, sunburn, and growth cracks can be high under some conditions; however, hollow heart, internal heat necrosis, and vascular discoloration are not usually a problem. Tubers of Reeves Kingpin are relatively tolerant to shatter and black spot bruise. The plants of Reeves Kingpin are relatively taller, with greener leaves, more flowers, and moderate to heavy fruit set compared to Russet Burbank. The late-season vigor of Reeves Kingpin is an advantage compared to Shepody, but its haulms can be hard to kill prior to harvest, particularly if over-fertilized. Reeves Kingpin is resistant to tuber net necrosis and moderately resistant to verticillium wilt and early blight. However, it is susceptible to golden cyst nematode, late blight, bacterial ring rot, and corky ring spot virus and moderately susceptible to common scab.     

Effect of two forms of maleic hydrazide on the cell structure at the midsection,stem and bud ends of the cortical and perimedullary regions of Russet Burbank tubers

The cortical and perimedullary cells of the potato tuber increased in size when treated with the diethanolamine and the potassium salt of maleic hydrazide. The best time for maleic hydrazide application appeared to be from mid to late July. There was a greater increase in cell size in the cortex than the perimedullary region and treatment with the amine salt was more effective than the potassium salt. The cells were smallest at the bud end; however, with maleic hydrazide treatment, increase in cell size was greater in this region compared to the midsection and stem end. From late August to late September the cell size of untreated tubers remained relatively unchanged, whereas, tubers treated with the amine salt showed a 16 to 46% increase with a lesser increase with the potassium salt. The rounder form of the treated tubers can be explained by the shape and increase in cell size in the cortical and perimedullary region. Increase in cell size also may help prevent the formation of misshapen tubers.     

Modoc: A potato variety with bright red skin and early maturity for fresh market

Modoc is an early maturing, red-skinned, whitefleshed potato cultivar for fresh market use. The Agricultural Experiment Stations of Oregon, North Dakota, California, Idaho, and Washington jointly released Modoc in 2003. Modoc was derived from a 1989 cross of ND1196-2R and ND2225-1R performed at North Dakota State University. Modoc retains bright skin color in storage and is suited for marketing directly from the field or storage. It produces slightly lower total yield than Red LaSoda or Dark Red Norland, but higher marketable yield and more desirable tuber size and shape. Modoc tubers seldom exhibit growth cracks, secondary growth, hollow heart or other external or internal defects. Dry matter content of Modoc tubers is similar to Dark Red Norland and Red LaSoda (18.9% compared to 18.8% and 17.7%, respectively). Culinary quality of Modoc was rated equal to Dark Red Norland and Red LaSoda for boiling and microwaving preparation methods. Modoc tubers are similar to standard varieties in sugar, vitamin C, and glycoalkaloid (4.5 mg/100 g) concentration. Modoc foliage clearly expresses PVY symptoms and has not demonstrated high susceptibility to viral or fungal diseases during a decade of seed production and evaluation.     

An assessment of true potato seed families ofSolanum phureja

Summary Experiments were carried out withSolanum phureja germplasm which had been selected for tuberization response under W. European growing conditions. Selected clones and seedling (true potato seed; TPS) families ofS. phureja were raised in the field and tubers assessed for yield, tuber number, skin colour, size, shape and cooking characteristics. Some families had low within-family variances for cooked flesh hardness and some appeared as uniform for tuber size and shape as the selectedS. phureja clones. Skin colours of the tubers within TPS families were often assorted. The commercial potential ofS. phureja as a possible TPS-derived crop is discussed, as its self-incompatibility makes possible the cheap production of true potato seed.