Tuber Grade Research Articles

Fertilization of Russet Burbank in short-season environment

A three-year investigation determined effects of N, P, K, and S rates on tuber yield and quality, economic return, and plant nutrient status of Russet Burbank grown on mineral soils in the Klamath Basin of Oregon. Yield responses were consistent over years. The highest yields and economic returns were achieved with the combination of 202 kg N, 29 kg P, 56 kg K, and 22 kg S ha-1. Petiole NO3-N concentrations were below published critical levels at the optimal N fertilizer rate of 202 kg N ha-1. Yield and economic return responses to increasing N rates were positive but small. The highest yield occurred at the lowest P rate (29 kg ha-1). Tuber yield, grade, or quality did not respond to K fertilization. Findings suggest that nitrogen fertilizer management based on petiole analysis may require modifications for short growing-season environments.

Zone-subsoiling effects on potato yield and grade

Soil compaction and erosion are problems in many Pacific Northwestern potato fields. We wanted to determine if zone-subsoiling would reduce these problems and improve potato yields and or grade without adversely impacting other production practices. Studies were conducted in Southern Idaho at six locations over two years on different soils and with different irrigation methods to assess the effects of zone-subsoiling immediately after planting on tuber yield and grade. Reservoir-tillage comparisons were made at three locations where sprinkler water application rates were higher than soil infiltration rates. Russet Burbank was represented by eight location-years and Russet Norkotah by two. Zone-subsoiling consistently improved tuber grade or increased tuber size. The biggest improvement was under furrow irrigation. Zone-subsoiling also tended to increase total yield in eight of ten location-years. Reservoir-tillage improved yield and grade, but zone-subsoiling did not without reservoir-tillage when water application rates were high. At no location did zone-subsoiling significantly decrease tuber grade or yield. Zone-subsoiling had no appreciable effects on hill configuration or seed-piece dislocation. Surface cracking and “water piping” occurred under furrow irrigation but were not significant problems. Results were similar for both cultivars. Additional studies will be needed to successfully incorporate zone-subsoiling into commercial production practices

Effect of altering the physiological age of potato seed-tubers in the fall on subsequent production in a short-season environment

The efficacy of utilizing "controlled seed-tuber aging" as a technique to enhance yield and improve tuber quality in areas with relatively short growing seasons was investigated in a 3-yr study. Prior to planting in the field, five physiological ages of Russet Burbank, Carlton, Norchip and Superior seed-tubers were produced by varying the heat-unit accumulation over a 200-d storage interval. Total yield increases of up to 90% and substantial improvements in tuber grade were achieved by planting aged (600–900 degree-day (dd)) seed-tubers. Plant growth from aged Russet Burbank seed-tubers was modelled to identify the mechanisms by which yield and quality were altered. Growth analysis demonstrated that the age-induced yield increases were due to faster emergence, faster leaf-area establishment, and tuberization earlier in the growing season compared with that from younger seed-tubers. The annual life cycle was thus accelerated, allowing plants from older seed-tubers to utilize the short (120-d) growing season more efficiently than those from younger seed-tubers. This was reflected in a higher harvest index: plants from 739 dd seed-tubers partitioned 63% of their total fresh weight into tubers compared with 48% for those from 66 dd seed-tubers (based on the quadratic model describing the relationship between seed-tuber age and and harvest index at 121 d after planting). The technique appears to be very promising for enhancing yield and/or promoting ’earliness’ of potatoes in regions with short growing seasons.Key words: Solanum tuberosum, seed-tuber age, plant growth, yield

Effects of soil moisture deficits on yield and quality of ‘Russet Burbank’ potatoes

Abstract A ‘Russet Burbank’ potato crop was subjected to 14 irrigation treatments in a rainshelter experiment at Lincoln, New Zealand in the 1987–88 growing season. In 12 treatments, plots were trickle irrigated and covered automatically by the shelter whenever rain fell, so that precise responses of yield and quality to water deficit timing and severity could be obtained. These treatments ranged from overwatering to withholding water to develop maximum potential deficits of up to 138 mm. The water stress treatments were applied either ac tuber initiation, early tuber bulking, or late tuber bulking (assessed by sampling spare plants). Except when fit was raining, these plots were exposed to prevailing climatic conditions. The two remaining treatments, which were outside the rainshelter, checked for direct effects of the shelter on the crop. One treatment was irrigated to achieve the same deficits as one of the treatments inside the rainshelter, and the other was not irrigated. Highest yields of process grade tubers (63 t/ha} were obtained from the overwatered plots. Among the drought-stressed treatments, the highest yields were 58 t/ha of process grade tubers, obtained from plots subjected to drought during tuber initiation; these had fewer bit larger tubers. Drought during late tuber bulking reduced process grade yields by 20%, with both tuber size and tuber number being reduced by up to 20%. Non-irrigated rainfed plots outside the shelter had low yields and small tubers because the season had half the average rainfall. The levels of water deficit imposed had no effect on tuber processing quality.

Labelle: A widely adapted high yielding white skin potato cultivar

LaBelle is a round-blocky, white skinned, white fleshed, smooth, shallow-eyed potato cultivar that is widely adapted and medium late in maturity. It produces a high total yield and a very high percent of number one grade tubers. LaBelle was rated first in overall merit in the 1984 and 1985 North Central Regional trials.

Comparison of 10 clones of the potato cultivar, Kennebec

Nine clones of Solanum tuberosum L. cv. Kennebec from sources in Victoria, South Australia and Tasmania, and the commercially grown clone, clone 1, which was imported from Vancouver, were multiplied from pathogen-tested seed and compared in 3 Victorian potato districts during 2 seasons. Haulm appearance of the 10 clones was similar. Tubers of clones 2 and 9 had a more desirable elliptical shape with shallow eyes than clones 1, 7, 8, 11 and 13. Clone 7 produced significantly (P<0.05) less total yield than the highest yielding clone at 3 sites. Compared with the other clones, clones 2 and 7 yielded significantly (P<0.05) less oversize (>450 g) and medium (100-450 g) tubers and significantly (P<0.05) higher yields of small (<100 g) tubers at several sites. Clone 1 produced a much higher proportion (5.7%) of total yield as oversize tubers than clones 2 (1.6%) and 7 (0.8%). Clones 2 and 7 produced a significantly higher (P<.05) number of tubers per plant than all other clones at the 3 sites. Averaged over these 3 sites, clones 2 (and 7) produced 6.2 (6.8) tubers per plant and the other clones were in the range 4.5-5.0. No consistent differences in specific gravity or crisp colour were observed between the clones. Clone 2 was selected as being best suited for the crisp processing industry because of its even shape, high number of tubers per plant and low yield of oversize tubers, while maintaining high yields and good specific gravity and crisp colour. Our results show that differences exist in total and size grade yield and tuber number and appearance between clones of a cultivar. They further highlight the importance of selection work to maintain desirable characteristics of established cultivars and to remove mutants with undesirable characteristics.

Daminozide reduces mean weight of potato tubers but fails to increase uniformity

At 3 sites in South Australia daminozide reduced mean potato tuber weight by 9-13% (P<0.05). Total yield of potatoes was reduced by 6-11%, although the effect was significant (P< 0.01) at only 1 site (Purnong Landing, reduction 11%). There were no effects of daminozide on tuber number, uniformity of tuber weight, specific gravity of tubers (at 1 site) or yield of ware grade tubers (80-350 g fresh weight). However, daminozide increased yield of grades (90-130 g) by 40% and decreased yield of grades (260-350 g) by 32% (P<0.05). In achieving these results, rates of 0.85, 1.7, 3.4 and 6.8 kg a.i. ha-l of daminozide were about equally effective. We conclude that, unless there is a market requirement for tubers of 90-130 g in weight, daminozide should not be used for the cultivars Sebago, Exton and Coliban if haulms are killed by herbicide or disease from 15 to 30 days before natural plant senescence. Stem length and leaf area index were reduced early in the season by daminozide, but late in the season leaf area index was increased.

Potato responses to calcium application on several soil types

On low cation exchange capacity, sandy soils where soil test Ca is low, potato tuber (Solanum tuberosum L.) Ca levels may not be optimal for maximum yield or quality; therefore, this study evaluated the effect of several levels of applied Ca on potato yield and quality on four soil types in Wisconsin. Calcium was applied to a Plainfield loamy sand, a Keiner loamy sand, a Pence sandy loam, and an Antigo silt loam at five rates in 1984 (0, 84, 252, 420, and 588 kg Ca ha−1) and at six rates in 1985 (0, 56, 112, 168, 224, and 336 kg Ca ha−1) as a band of CaSO4 in the hill. In 1984, on the Plainfield soil, three rates of sidedress Ca(NO3)2 (0, 84, and 168 kg Ca ha−1) were factorially combined with the five CaSO4 treatments to evaluate the efficacy of Ca(NO3)2 as a concomitant Ca and N source. In general, total yield was not affected by CaSO4 additions; however, the addition of approximately 100 kg Ca ha−1 as Ca(NO3)2 increased total yield 3.6 Mg ha−1. On the low-CEC, low-Ca soils (Plainfield and Kelner), improved tuber grade and/ or US1A size grade were detected with the addition of up to approximately 300 kg Ca ha−1 as CaSO4. The percent of US1A tubers increased 5 to 10% and the yield of US1A prime size (170–370 g) tubers increased 3.4 to 8.4 Mg ha−1 above control values. These improvements were accompanied by increased periderm Ca concentrations, even though leaflet Ca concentrations were not affected by Ca applications. The use of 100 kg Ca ha−1 asCa(NO3)2 in combination with CaSO4 was more effective than CaSO4 alone. On higher soil test Ca soils (Pence and Antigo), responses were inconsistent and periderm Ca was generally not increased.

The effect of subsoiling and irrigation on potato production

Thin tillage pans restrict water movement and potato ( Solanum tuberosum L.) root penetration in fine-textured soils of the Columbia Basin in central Washington State, U.S.A. Deep chiseling beneath potato rows, with simultaneous deep incorporation of fertilizer, was used to break-up the pans, enabling deeper root development. The effects of subsoiling on soil physical conditions and on potato production were examined under varying rates of irrigation. Deep tillage decreased soil strengths and bulk densities and increased porosity to depths of 10–16 cm below the pans. These improved subsoil physical conditions resulted in deeper root penetration, but the additional rooting only amounted to a small increase to the total root system. Cubic polynomial regressions demonstrated that subsoiling significantly increased potato yields under very droughty conditions but had no significant effects at intermediate (near optimum) levels of water application. Potato quality (percentage of U.S. No. 1 grade tubers and tuber specific gravity) was generally unaffected by deep tillage. These results indicate that, for potatoes, appropriate irrigation management can be used to overcome problems of restricted root penetration and impeded water movement caused by tillage pans.

Response of Nooksack potatoes to nitrogen fertilizer

The Nooksack cultivar because of differing characteristics may have different responses to grower management practices developed principally for Russet Burbank. This study was conducted to determine the effects of nitrogen on yield, grade, and specific gravity of the Nooksack cultivar. In irrigated field experiments, N fertilizer was sprinkler-applied daily on Quincy sand soil. In other experiments, on a Warden silt loam soil all N was broadcast and incorporated before planting. Fertilization rate did not significantly affect tuber grade or specific gravity. Short term shifts in N supply did not cause tuber deformities and poor grades as they commonly do with Russet Burbank. Nooksack, while responsive, did not have a strong positive response to N fertilization. Tuber yields were depressed at fertilizer plus residual N levels above 200 kg/ha on Warden silt loam and above 300 kg/ha on Quincy sand. This difference was because of variation in NO3 leaching and soil N mineralization and was reflected in calculation of optimum N rates. Nooksack may require less N fertilization than Russet Burbank partially because of the strong dormancy of Nooksack tubers that retards emergence and shortens growing season. Management to promote more rapid dormancy break and lower N nutrition during tuber initiation could result in earlier establishment, earlier tuber bulking, and greater yields of Nooksacks.

Plant growth response from aged potato seed-tubers as affected by meristem selection and NAA

Plant growth from Russet Burbank seed-tubers of different ages was compared as affected by source of meristematic tissue (apical or basal) and NAA treatment. In controlled environment studies, single-eye seedcores from 17-mo-old seed-tubers produced twice as many shoots compared to those from 5-and 29-mo-old seed-tubers. Seed-tuber age and shoot dry weight/core were inversely related. Dry weight/shoot decreased as age increased to 17 mo and then remained unchanged from 17 to 29 mo. Apical meristems lost growth potential faster than basal meristems as age advanced. Meristem physiological age apparently depends on relative position of the buds as well as on the chronological age of the seed-tuber. NAA (10–40 mg/l) decreased the number of shoots/core, had no effect on shoot dry weight/core but increased the dry weight/shoot when applied to seedcores from 20-mo-old seed-tubers. On seedcores from 8-mo-old seed-tubers. NAA decreased the shoot dry weight (g/core, g/shoot). In field studies, NAA (100 mg/l) increased the total tuber yield of plants grown from seedpieces cut from 8-and 20-mo-old seed-tubers. These increases were manifested in age-specific effects on tuber grade. The effects of seedtuber age on plant growth and tuber yield were partially overcome by seedpiece treatment with NAA.

Metalaxyl and other fungicides for control ofPhytophthora infestans on potato in northwest Washington State

In northwest Washington State, fungicidal control of late blight caused byPhytophthora infestons was evaluated for three years. During 1977, a high rainfall year with supplemental sprinkler irrigations, all metalaxyl and chlorothalonil treatments reduced tuber rot at harvest, but only metalaxyl extended control of tuber rot after 4 months’ storage. During 1978, a high rainfall year, one application of metalaxyl sprayed over or dusted on potato seed pieces at planting or applied five times to foliage at 2 or 4 wk intervals gave excellent blight control equal to that with chlorothalonil applied to foliage every 2 wk. In 1979, a low rainfall year,P. infestons did not kill plants in untreated plots until October. Five applications of metalaxyl sprayed every 2 wk on foliage did not control foliage blight. However, metalaxyl reduced foliage blight when dusted on cut potato seed pieces. Mancozeb sprayed every 2 wk also gave excellent control. The possibility that metalaxyl applied to foliage is effective in late blight control only when washed into the soil by rainfall or irrigation for uptake by roots is discussed. Yields and percent U.S. No. 1 grade tubers were not significantly affected by any treatment in these 3-year trials.

Effect of daily irrigation rate and soil texture on yield and quality of Russet Burbank potatoes

Adequate soil water is needed for satisfactory yield and quality of potato tubers. With sprinkler irrigation systems it is common practice to apply more water than the crop uses in order to maintain high soil water levels. A study was initiated to evaluate the response of Russet Burbank potatoes to a wide range of daily sprinkler irrigation rates when grown on two soilsa loam and a sand—differing in water holding capacity. The results from the two soils were very different. On the loam soil, yields generally increased with increased applications of water, up to the equivalent of 40 to 50% estimated Et. Irrigation treatment effect on percent No. 1 tubers was inconclusive. In 1978, percent No. 1 tubers increased with water applied up to about 70% estimated Et. In 1980, irrigation rates between the equivalent of about 20 and 80% estimated Et had little effect on tuber grade. Yields and percent No. 1 tubers were depressed at irrigation rates greater than about 80% estimated Et. On the sand, yields and percent No. 1 tubers increased with increased irrigation rates up to about 100% and 80% estimated Et, respectively. Tuber specific gravity was not affected to an important degree by irrigation treatment on either soil. These results indicate that a good crop of potatoes can be grown on a loam soil at daily irrigation rates considerably less than estimated Et rates, while such reductions will decrease yields and grade on a sandy soil.

Susceptibility of twenty potato cultivars to the potato moth at Pukekohe: A preliminary assessment

Abstract In a field study 20 potato cultivars were compared for relative levels of foliar and tuber infestation caused by the potato tuber moth (Phthorimaea operculella (Zeller)). All became seriously infested and showed no evidence of resistance. ‘Wha’, ‘Ono’, and ‘1584c10’ were the least seriously affected cultivars when assigned a performance rank based on a combination of foliage mining intensity, level of table grade tuber infestation, and total tuber yield. Varieties with a prolonged upright growth habit and few leaves close to the soil surface sustained low foliage mining populations. Light tuber infestation was also associated with plant growth habit, such as deeper tuber set, rather than with true resistance.

Cultural practices in relation to infestation of potato crops by the potato tuber moth

Abstract In a field trial at Pukekohe the effect of sprinkler irrigation and wide ridging (91 cm) on potato infestation by the potato tuber moth Phthorimaea operculella Zell., Lepidoptera, Gelechiidae was assessed in a season of unusually low rainfall. Infestation of table grade tubers was 10% under sprinkler irrigation compared with 86% under no irrigation. Irrigation increased tuber yield four-fold. The combined effects of irrigation on tuber infestation plus yield produced a 27.9-fold increase in marketable potatoes, from 1513 kg/ha to 41 297 kg/ha. Wide ridging was associated with reduced infestation of table grade tubers. Closer spacing of seed to maintain correct plant density per hectare did not affect tuber yield. No interaction between irrigation and row width was detected. Irrigation reduced foliage-mining intensity (number of miners per unit available leaf). As the crop matured, foliage was denser under irrigation, and the actual population level (number of miners per unit land area) was higher...

Foliar damage, residue levels and tuber yield in potato treated with various concentrations of 2,4-D at three stages of growth

A field trial with potato plants treated with 0, 0.1, 1 and 10 p.p.m. 2,4-D at the emergence, flowering and flower drop stages was conducted. Symptoms of foliar damage were noted a month after the treatments. The susceptibility of the plants to 2,4-D damage decreased in the order of emergence, flowering and flower drop of the plants, irrespective of the concentration of the herbicide. There may be economic loss for producers of seed potatotes owing to the foliar 2,4-D damage. Residues of 2,4-D in both foliage and tubers were determined. The limit of detection was 0.005 p.p.m. The average recovery of 2,4-D amine and acid from fortified foliage and tubers was 81 to 87 per cent. Residue levels of 0.110 p.p.m. 2,4-D were found in the slightly damaged foliage following application at flower drop, but only 0.010 p.p.m. was found in severely damaged foliage following application at emergence. Traces of 2,4-D residue were found in the tubers after the plants had reached maturity. In general, tuber yield (numbers, weight and specific gravity) was not affected by the various concentrations of 2,4-D applied at the three stages of growth. However, it appeared possible that the yield of No. 1 grade tubers might be slightly reduced when plants are treated at emergence, irrespective of the concentration of the herbicide.

The suitability for canning of some potato varieties

Unreplicated plots of up to 29 varieties were grown for three years at a high plant density and until maturity when the dry matter content and canning characteristics of the 20–40 mm grade tubers were assessed. A low dry matter content was not always associated with freedom from breakdown on canning. Several varieties showed promise butMaris Peer was considered the best withArran Pilot andSutton's Foremost receiving qualified commendation.