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1.
The stem and bud portions of Russet Burbank tubers held at 70 F (21.1 C) for 2 weeks had significantly more reducing sugars at holding temperatures of 45 (7.2 C) and 42 F (5.6 C) than tubers immediately placed in 45 and 42 F storage. At a holding temperature of 48 F (8.9 C), no differences were found Two-week pre-holding temperatures of 42, 45, 56, and 70 F followed by a holding temperature of 42 F were compared. Sugar accumulations tended to be minimal at pre-holding temperatures of 48 to 50 F. Reducing sugar accumulation increased as pre-holding temperatures increased or decreased from this optimum. Longer periods of pre-holding temperatures at 48 F delayed sugar accumulation; however, the eventual total amounts of reducing sugars in May at a holding temperature of 42 F were similar, whether pre-holding periods were 1 to 2 months or 4 to 5 months  相似文献   

2.
Tubers of Russet Burbank potatoes were stored at 36 F (2.2 C), 42 F (5.6 C), 45 F (7.2 C), 48 F (8:9 C), and 70 F (21.1 C) and respiration rates determined. Chemical treatments 4 with growth regulators were made and respiration rates determined on intact tubers. Tubers stored 42 F (5.6 C) and 45 F (7.2 C) generally respired less and at a more uniform rate than tubers stored at other temperatures. The respiration rate of CIPC and BA (20 ppm) treated tubers was less than the untreated tubers.  相似文献   

3.
Russet Burbank tubers from plants which died prematurely (low fertility plots) accumulated significantly greater amounts of reducing sugars in storage than tubers from plants which were adequately fertilized. Also, a significantly greater difference in relative amounts of reducing sugars between the apical and basal portions was obtained from tubers of the low fertilizer regime. The basal portion had a three times greater amount of sugars than the apical portion. This is of particular interest to processors of French fries who try to obtain uniformity of color in processed fries. The difference in total reducing sugar accumulation in storage between tubers of high and low fertilizer regimes was greater at the lower storage temperatures. Tubers allowed to mature in the ground (second harvest date) accumulated less sugars in storage than tubers dug shortly after vine kill.  相似文献   

4.
Idaho-grown Russet Burbank potatoes treated with a sprout inhibitor were stored at 42 F, 45 F, and 48 F for 11 months. Monthly quality evaluations showed that tubers stored at 42 F were less mealy, contained more reducing sugars, and were yellower in color than those stored at 45 F or 48 F. The latter two treatments were not significantly different in mealiness and were generally similar in yellowness of color. Tubers stored at 48 F had less reducing sugars than those stored at 45 F. Although all treatments resulted in a gradual darkening of the potatoes during storage, differences in grayness among the three storage treatments were minor from a practical standpoint. It is suggested that a storage temperature no lower than 45 F be used to maintain the internal quality of Russet Burbank potatoes.  相似文献   

5.
Basal and apical portions of mature and immature Russet Burbank tubers stored at 42 F (5.6 C), 45 F (7.2 C), and 48 F (8.0 C) were analyzed for sucrose and reducing sugars at seven monthly intervals for three seasons. Percent relative difference of reducing sugars (between mature and immature tubers) was greater in the apical than the basal portion. On the other hand, seasonal differences in percent reducing sugars were reflected more in the basal portion by greater relative differences among seasons than in the apical portion. Statistical analysis showed no trend or influence of maturity or storage temperature in affecting the relativeratio of reducing sugars between the basal and apical portions. Differences among growing seasons appeared to affect this ratio. Tubers from the 1970–71 season had more equal relative amounts of sugars in the two portions than did the tubers from 1968–69 or 1969–70 seasons. Ratio ofsucrose between the basal and apical portions was not affected appreciably by maturity, storage temperature or season, although immaturity and lower storage temperatures caused slightly greater overall sucrose accumulation. Sucrose and reducing sugar contents were poorly correlated regardless of maturity, storage temperature or different seasons.  相似文献   

6.
Potato virus X (PVX)-free and mild PVX-infected tuber lines originating from the same Katahdin clone were compared for susceptibility to tuber rot incited byFusarium roseum (Lk.) Synd. and Hans. ‘Avenaceum’. The effect of interval between top-kill and harvest on development ofFusarium tuber rot was also determined. A series of tubers from both PVX-free and PVX-infected tuber lines was either (i) mechanically bruised and inoculated by immersion in a spore suspension ofF. roseum ‘Avenaceum’, (ii) mechanically bruised but not inoculated, (iii) inoculated only or (iv) neither bruised nor inoculated. Tubers from all treatments were then stored at temperatures of 18–21 C (65–70 F) for a 3-week period prior to being placed at 4 C (39 F) for the remainder of the storage period. The amount of rot was determined after a 5–6 month storage period at the latter temperature. In a 4-year study PVX-free tubers were significantly (1% level) more susceptible to infection byF. roseum ‘Avenaceum’ than tubers infected with mild PVX. PVX-free tubers left in the ground for 2 or 3 weeks after top-kill were significantly (1% level) more susceptible toFusarium dry rot than those infected with the virus; however, there was no significant difference in disease incidence between PVX-free and PVX-infected tubers when harvested 4–5 weeks after top-kill. Tubers, both PVX-free and PVX-infected, remaining in the ground for a 2 week period following top-kill were significantly (1% level) more susceptible toFusarium tuber rot than those harvested 3 weeks after top-kill; similarly, both PVX-free and PVX-infected tubers harvested 3 weeks after top-kill were significantly (1% level) more susceptible than those left in the ground for a 4–5 week interval.  相似文献   

7.
The incidence of tuber decay in rail car shipments of potatoes from the State of Washington was determined from 1965 to 1969 inclusive. Reinspection certificates revealed that 7.9% of the rail cars of potatoes shipped during this period were rejected due to tuber defects; tuber decay accounted for 63% of these rejected cars. Percentage of rejections due to tuber decay was greater for Russet Burbank than for Norgold Russet potatoes. Temperature, moisture, and oxygen levels influenced development of bacterial soft rot in freshly harvested potatoes and in potatoes stored for 3 months at 35 F (2 C) previous to treatment. When tuber surfaces were kept dry, no soft rot developed in 11 days over ranges of 50–70 F (10–21 C) and 2–20.5% oxygen levels. Freshly harvested tubers partially immersed in water did not rot when cooled to 40 F (4.4 C) in < 24 hours and held for 8 days under either 20.5 or 4% oxygen levels; however, tubers, rotted when stored similarly but at 50 F or higher temperatures. Partially immersed tubers incubated for 1 day or longer at 70 F developed soft rot in a low oxygen (4%) when later stored for, 8 days at 40 F. When rot occurred, the amount was always greater under lower oxygen levels irrespective of storage temperature. Of various cooling methods tested in rail cars loaded with 100 lb (45.4 kg) sacks of potatoes, prechilling of tubers and icing of cars prior to loading lowered floor temperatures most rapidly. Icing cars after loading lowered floor temperatures the slowest. In a carton shipment, the temperature remained above 68 F (20 C) in cartons after 8 days in transit, even though the wall and floor temperatures had cooled to near 55 F (12.8 C) by the second day. Oxygen level surrounding, tubers in the center of car loads of 100 lb sacks of potatoes was approximately 20.5% after 8 days transit.  相似文献   

8.
Russet Burbank and Shepody potatoes of different chemical maturities (i.e. varying sucrose concentrations) at harvest were preconditioned by holding at 15 C for various durations to lower the concentration of reducing sugars to levels acceptable for processing as french fries out of 8 C storage. In chemically immature tubers (i.e. those harvested with a high sucrose), sucrose declined after harvest and stabilized in storage regardless of the preconditioning period. However, there was a temporary small increase in sucrose after harvest in more chemically mature tubers. The concentrations of the reducing sugars glucose and fructose were low at harvest, usually < 1.0 mg g?1, but increased rapidly during the first 30 to 45 d of storage in tubers with more than 2.0 mg g?1 sucrose at harvest. Preconditioning for up to 70 d at 15 C either limited the increase in reducing sugars or lowered them more rapidly during storage than when preconditioned for only 14 d. Fresh weight loss of Russet Burbank and Shepody was greater in physically and chemically immature tubers compared to more mature tubers. Extended preconditioning of Russet Burbank and Shepody resulted in minimal additional weight loss.  相似文献   

9.
Potato (Solanum tuberosum L. cv. Russet Burbank) tubers were harvested weekly over a 6 week period from non-water-stressed and water-stressed plants. Discs were cut from fresh tubers and from tubers stored for 10 days at 4°C to determine their wound healing ability as evaluated by disc resistance to water loss. Neither harvest date nor water status significantly influenced wound healing while storage significantly increased wound healing ability. Enhanced wound healing associated with storage was accompanied by reduced variability of disc resistance to water loss and increased levels of suberin as reflected by the diol and alcohol components. This work suggests that plant senescence and harvest date are not good indicators of the potential wound healing ability of tubers. Physiological evidence is presented to support the practice of short periods of storage following harvest to improve tuber wound healing ability and thereby reduce shipping and handling losses due to injury.  相似文献   

10.
Studies were made of pH changes of apical and basal portions of Russet Burbank and Norgold Russet potatoes during growth and in storage. Russet Burbank had a higher pH of the apical portion during the later stages of growth as compared to the basal portion. No significant differences between the two portions were found during growth with Norgold Russet. After a period of moisture stress the pH of the basal portion of Russet Burbank dropped significantly. The basal portion of both varieties at higher specific gravities had higher pH after storage than the apical portion. A highly significant negative correlation was obtained after storage between reducing sugar levels of tubers of different specific gravities and pH levels in both varieties. There were no significant differences in pH among storage temperatures of 34, 38, 42 and 45 F. However, the pH level at 48 F storage was significantly higher than at the other temperatures. The pH level of tubers from seedlings and varieties were poorly correlated with their reducing sugar contents after storage. It appears that pH can be an indicator of potential chip color only within the confined limits of a specific lot.  相似文献   

11.
In three experiments with cvs Diamant (short dormancy) and Désirée (long dormancy), the effect of a haulm application of gibberellic acid (GA) on the dormancy of seed potatoes harvested immature was investigated. Several storage temperature regimes were imposed to examine the interaction between GA and storage temperature. The storage regimes included 18 and 28 C continuously, hot pre-treatments of different duration (different periods at 28 C and subsequently 18 C) and a cold pre-treatment (20 days at 2 C and subsequently 18 C). A foliar spray of 375–750 g GA/ha 3–6 days before haulm killing shortened dormancy, and minimally induced sprouting before harvest. The magnitude of the GA effect depended on the cultivar and storage temperature regime. Compared to untreated tubers stored at 18 C, dormancy was shortened by about 40 days by a GA application and storage at 18 C (Diamant) or by about 90 days by a GA application and storage at 28 C (Désirée).  相似文献   

12.
Change in weight and, to a lesser degree, in specific gravity of tubers during storage was much more dependent on relative humidity than on temperature. Katahdin usually lost more weight and showed a greater increase in specific gravity than Russet Burbank. The increase in weight loss of cured tubers in the course of the storage period was nearly always linear. The increase in specific gravity was often particularly pronounced at the end of the storage period. Black spot susceptibility decreased during the storage season and was sometimes affected by temperatures as well as relative humidity. In the cases that these influences were significant, colder and drier storage conditions resulted in less susceptible tubers than higher temperatures and relative humidities, but the differences were small. In one year out of three Russet Burbank was more susceptible than Katahdin, once the opposite was true, and once there was no difference between them. Susceptibility to damage, which decreased during the storage period in two out of three years, was greater at lower temperatures and higher humidities than under warmer or drier storage conditions. Variety differences were not consistent.  相似文献   

13.
Freshly harvested microtubers produced by Wye and CIP methods were treated with Rindite and then stored at 6 C under continuous light or in dark. After 12 weeks, storage behavior, dormancy break and subsequent sprout growth were assessed. Increased period of Rindite treatment and storage in light caused significant weight loss of microtubers. Greater weight loss was recorded from International Potato Center (CIP) microtubers and those stored in the light versus in the dark. Wye microtubers treated with Rindite for 48 hours and stored under light tended to have more microtubers with 2 or 3 sprouts per microtuber than single sprouts. Fresh weight of sprouts was also greater in Wye microtubers when treated with Rindite for 48 hours and stored under light. Longest sprout length increased with increased duration of Rindite treatment.  相似文献   

14.
Shortening dormancy of seed potatoes by storage temperature regimes   总被引：1，自引：0，他引：1  
Summary Four experiments (three with four cultivars, one with twenty cultivars) investigated the effect of different storage temperature regimes on the duration of dormancy of seed potatoes harvested immature. Regimes included constant temperatures (18 and 28°C), hot pre-treatments (20 days at 28°C and subsequently 18°C) and cold pre-treatments (20 days at 2°C and subsequently 18°C). Compared with 18°C, storage at 28°C slightly prolonged dormancy of some cultivars with a genetically short dormancy and shortened dormancy by up to 45 days in cultivars with a long dormancy. Some tubers of one cultivar lost their ability to sprout after storage at 28°C for 90 days. A hot pre-treatment shortened dormancy by 2–3 weeks on average, for all cultivars examined. A cold pre-treatment shortened dormancy by 2 weeks on average in some cultivars with a short dormancy and in all cultivars with a long dormancy.  相似文献   

15.
Potato (Solanum tuberosum L. cv. Russet Burbank) tuber periderm resistance to water loss was monitored during the harvest season. Periderm resistance of tubers from water-stressed plants was compared with tubers from unstressed plants throughout a six-week harvest period, in order to determine the effect of plant condition on tuber resistance to water loss. Tubers stored for ten days at 4°C immediately following harvest were also monitored to determine if storage enhanced periderm resistance and if any difference occurred between tubers from stressed vines compared with those from unstressed vines. During the harvest season, tuber resistance to water loss was positively correlated with plant water stress, as measured by leaf water potential and leaf diffusive resistance. Storage of tubers after harvest also caused an increase in periderm resistance. The commercial practice of vine killing, therefore, may have a positive effect on reducing weight loss in storage by enhancing the resistance of tuber periderm to water loss.  相似文献   

16.
Field experiments were conducted in 1995, 1996, and 1997 at Agriculture and Agri-Food Canada’s Harrington Research Farm to assess the effect of whole seed tuber size and pre-plant seed storage conditions on processing yield (> 51 mm dia.) of potato (Solanum tuberosum L. cv Russet Burbank). Following commercial storage, seed tubers were stored at 4.4 C then subjected to one of three pre-plant treatments: (1) planted directly from storage, (2) held at 10 C for 3 wk before planting, or (3) green-sprouted for 3 wk before planting. Five sizes of whole seed were used (28, 42, 56, 70, and 84 g) with a variable size cut seed treatment added for comparison. Plots were harvested 138,134, and 131 days after planting in 1995, 1996, and 1997, respectively. Cut seed produced a higher yield of tubers > 51 mm diameter in comparison to all whole tuber seed sizes, with the exception of the 28 and 56 g sizes. In terms of total yield, the 28and 42-g whole seed tubers yielded significantly less than all other seed sizes examined. Warming or greensprouting seed tubers prior to planting did not increase tuber yield. The larger whole seed tuber sizes tended to result in greater numbers of stems and tubers per plant. To maximize marketable yield of Russet Burbank planted from whole seed tubers, it is recommended that the seed be between 28 and 42 g in size. Accepted for publication 25 May 2004.  相似文献   

17.
Throughout a 7-month storage period, Russet Burbank tubers continuously ventilated at 32 F (0 C) and 45 F (7.2 C) with atmospheres of 2% O2, air, 4% CO2, and intermittently ventilated with air, evolved ethylene at a rate no greater than 0.008 μ 1 Kg?1 hr?1. Tubers stored in 80% O2 and 12% CO2 produced ethylene at much higher rates. In all cases where sprouting occurred, the rate of ethylene production increased. Inoculation withFusarium roseum greatly stimulated ethylene production but inoculation withAlternaria solani did not.  相似文献   

18.
Potato transplants (Solanum tuberosum) were harvested and stored at 1.7, 7.2, 12.8, 15.6 and 18.3°C between 4 and 8 days. The transplants were evaluated after storage for leaf color and drop, wilt, tuberization, and stolonization. After transplanting, the plants were evaluated for survival. At 1.7 and 7.2°C storage, the leaves were greener with less drop than at the higher temperatures. During storage above 7.2°C, the development of tubers and stolons continued. Plant survival was generally higher at 1.7, 7.2 and 12.8°C than at 15.6 and 18.3°C.  相似文献   

19.
Early potatoes are typically produced using less nitrogen than a full season potato crop as high rates of nitrogen may delay tuber set and lead to excessive vine growth that is difficult to terminate prior to harvest. Bintje and Ciklamen potato cultivars were grown with preplant soil nitrogen levels of 34 to 38, 67, and 101 kg N ha-1 in 2013 and 2014 near Paterson, Washington. Nitrogen rate had little impact on the number of tubers and stems per plant of both cultivars, but increasing nitrogen rate tended to increase leaf area of both cultivars. Vine desiccation of Bintje with diquat was less complete as nitrogen rate increased, while Ciklamen vine kill was reduced by higher nitrogen in 1 of 2 years. Tuber skinning injury, tuber weight loss, and tuber size distribution were not affected by nitrogen rate. Tuber skinning injury and tuber weight loss were reduced in both cultivars by harvesting at 4 weeks after initial vine kill compared to harvesting at 2 weeks after vine kill. Total tuber yield was lower for both Bintje and Ciklamen in 1 of 2 years at the 34 to 38 kg N ha-1 rate. Tuber nitrogen and zinc levels tended to increase with increasing nitrogen rates, while most other nutrients, vitamin C, total phenolics, and antioxidant capacity showed little response. It appears that 67 kg N ha-1 provides adequate nitrogen to produce a good tuber set and yield of small tubers while not producing excessive vine growth that may be more difficult to kill.  相似文献   

20.
Russet Burbank and WC230-14 potato tubers were stored at 0 C (32 F) and 5 C (41 F) in air, air plus 4% CO2 and air plus 8% CO2 for a 175 day storage period. Four times during this period, tubers were removed and inoculated withErwinia carotovora var.atroseptica (van Hall) Dye orFusarium roseum var.sambucinum (L. K.) Sn. and H. and stored at 17 C (62.6 F). Tuber samples were also reconditioned for two weeks at 17C(62.6 F) and then inoculated. Tubers were evaluated for rate of membrane permeability, free glucose, free fructose, and sucrose content and the rate of tuber decay by the two pathogens. Relative to 5 C (41 F), 0 C (32 F) storage increased sugar content, membrane permeability and the rate of tuber breakdown. Increasing CO2 during storage at 0 C (32 F) and 5 C (41 F) increased each of the above parameters. Reconditioning tended to alleviate the adverse effects of 0 C (32 F) storage and increasing CO2 levels, but varietal differences existed. A significant and high correlation was obtained between the rate ofErwinia decay, membrane permeability, and sucrose content of the tubers.  相似文献   

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