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There is ample evidence for global warming and resulting climate change. To sustain food production in view of climate change, we need to improve resistance to abiotic stresses in commercially desired cultivars. Using potato as an... more
There is ample evidence for global warming and resulting climate change. To sustain food production in view of climate change, we need to improve resistance to abiotic stresses in commercially desired cultivars. Using potato as an example, a strategy is illustrated for such improvement by merging physiological and genetic approaches. Potato (Solanum tuberosum L.) is a cool-season crop, cultivated in the temperate zone in North America, Europe, and the highlands of South America, Africa, and Asia. In these areas, frost is often a major factor limiting potato production. Climate change models predict erratic weather patterns including more severe and untimely frost episodes. Cultivated potatoes are highly frost sensitive and are often killed when tissue temperatures fall below −3°C. Several wild potato species are frost tolerant. These species carry two desired traits: 1) They can survive temperatures as low as −6°C while growing under normal conditions (NAFT), and 2) they are able to acclimate in response to chilling temperatures and increase frost tolerance and survive at temperatures as low as −12°C (CAC). These two important traits are lacking in cultivated potatoes. We have demonstrated that NAFT and CAC are genetically distinct traits that must be selected for individually and combined in a desired genotype. By precise screening for both NAFT and CAC, we have been able to select frost-hardy clones of potato that also carry commercially desired traits. This progress was made possible by understanding the physiological and biochemical mechanisms of frost survival and cold acclimation. We have shown that: 1) plasma membrane ATPase is an important site of cellular response to temperature stress, and this response appears to be mediated by changes in cellular/membrane calcium and changes in membrane lipid composition; 2) specific lipid composition changes occur in the plasma membrane that allow a plant to acclimate to cold and increase freezing tolerance, and an increase in the degree of unsaturation of specific lipids is important in this acclimation process. We have further shown that these changes in lipid are associated with an increased expression of Δ9 desaturase gene during cold acclimation; 3) calcium can mitigate the impact of heat, cold, and salinity on potato. In addition to NAFT and CAC, freezing avoidance is an important trait for plant survival. We have been able develop frost-hardy carrot hybrids by combining freezing tolerance in the top with freezing avoidance in the root. Taken together, our studies provide a systematic approach to improving abiotic stress resistances of crop plants and suggest strategies for developing production practices to mitigate the impact of abiotic stresses in a changing climate scenario.
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Wild potato species provide a valuable source of genetic variability for the improvement of freezing tolerance in cultivated potato, Solanum tuberosum (tbr). However, breeding for freezing tolerance by using wild genetic resources has... more
Wild potato species provide a valuable source of genetic variability for the improvement of freezing tolerance in cultivated potato, Solanum tuberosum (tbr). However, breeding for freezing tolerance by using wild genetic resources has been hampered by contradictory results regarding the genetic control of this trait. Both dominance and recessiveness for this trait have been reported. To explore the genetic control of freezing tolerance, the expression of freezing tolerance was investigated in various interspecific F1 and somatic hybrids between hardy and sensitive species. In addition to 2 years of field evaluation, freezing tolerance before and after acclimation was characterized separately under controlled environments to dissect the two independent genetic components of freezing tolerance, namely nonacclimated freezing tolerance (NA) and acclimation capacity (ACC). The expression of freezing tolerance, including NA and ACC, was closer to that of hardy parent, sensitive parent, or...
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Maize grain hardness influences storage pest resistance, a key characteristic valued by smallholder farmers. The structural changes in the endosperm determine grain hardness and are influenced by agronomic practices. The purpose of this... more
Maize grain hardness influences storage pest resistance, a key characteristic valued by smallholder farmers. The structural changes in the endosperm determine grain hardness and are influenced by agronomic practices. The purpose of this study was to establish whether supply of calcium and magnesium based fertilizers can alter physicochemical properties of local and hybrid maize varieties and reduce the infestation by larger grain borer (Prostephanus truncatus (Coleoptera: Bostrichidae)) during storage. Two local and one hybrid maize varieties commonly grown by smallholder farmers in Malawi were cultivated under three fertilizer treatments (NPK (nitrogen, phosphorous, potassium), NPK plus gypsum, and NPK plus dolomite). After harvest, the grains were classified into flint and dent types, followed by P. truncatus infestation and determination of their physicochemical properties. The addition of gypsum and dolomite fertilizers led to higher levels of amylose, total zein and β-14 zein, ...
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Research Interests: Biology, Crop Science, Germplasm, French Fries, Solanum Tuberosum, and 2 moreAsparagine and Acrylamide(Asparagine and Acrylamide)
(Asparagine and Acrylamide)
Four snap bean cultivars were grown during the summers of 1996 and 1997 in Hancock, Wis. Fertilizer treatments consisted on 80 kg of Ca/ha applied as gypsum (CaSO4·2H2O) or calcium nitrate [Ca(NO3)2], and the control (no calcium applied).... more
Four snap bean cultivars were grown during the summers of 1996 and 1997 in Hancock, Wis. Fertilizer treatments consisted on 80 kg of Ca/ha applied as gypsum (CaSO4·2H2O) or calcium nitrate [Ca(NO3)2], and the control (no calcium applied). The experimental design was a randomized complete block with a factorial set of treatments (4 × 3) repeated six times each year. Gypsum was all applied at planting, whereas calcium nitrate was applied weekly starting 1 week prior to flowering for 4 weeks. Yield and calcium concentrations in pods were determined. The statistical analyses showed no significant effect from fertilizer type on pod calcium concentration or yield. A strong cultivar effect was detected for both parameters measured. `Evergreen' (5.47 mg Ca/g dry wt) presented the highest pod calcium concentration and `Labrador' (4.10 mg Ca/g dry wt) the lowest. No significant fertilizer × cultivar interactions were observed. Results for pod calcium concentration remained consistent,...
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Research Interests: Biological Sciences, Sequence alignment, Physical sciences, Arabidopsis, Specific Activity, and 11 moreSubstrate Specificity, LPC, RT PCR, SIGNAL PEPTIDE, Protein isoforms, Amino Acid Sequence, Recombinant Proteins, Palmitic Acid, Linoleic Acid, Molecular Sequence Data, and Medical and Health Sciences
... volume. Specific heat is a measure of the energy required to raise 1 gram of a material lo celcius, and thermal conductivity is a measure of the amount of energy transmittable through a material via molecular bonds. However ...
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Previous research has provided evidence that Ca is transported to the tuber along with water via the roots on stolons and tubers. Several studies have documented that in-season Ca application can increase tuber Ca concentration and reduce... more
Previous research has provided evidence that Ca is transported to the tuber along with water via the roots on stolons and tubers. Several studies have documented that in-season Ca application can increase tuber Ca concentration and reduce storage rot and internal defects such as hollow heart, brown center, and internal brown spot. The objective of the present study was to
Research Interests: Nutrition, Prediction, Fertility, Calcium, Potato, and 5 moreSeasonality, Soils, Sol, Soil Type, and Horticultural production
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Page 1. Amer J of Potato Res (2004) 81:125-135 125 Evidence for the Up-regulation of Stearoyl-ACP (59) Desaturase Gene Expression during Cold Acclimation Sandra E. Vega 1, Alfonso H. del Rio 1, John B. Bamberg 2, and Jiwan P. Palta 1. ...
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Roots on potato tubers and stolons displayed the normal root anatomy which consisted of a central vascular cylinder surrounded by endodermis with Casparian strips, the cortex and epidermis. Tuber roots appear to initiate from the... more
Roots on potato tubers and stolons displayed the normal root anatomy which consisted of a central vascular cylinder surrounded by endodermis with Casparian strips, the cortex and epidermis. Tuber roots appear to initiate from the parenchyma cells adjacent to the vascular tissue. Shoot tips were similar to normal apical meristems. These observations support our research demonstrating the growth of functional
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Page 1. 1996 397 POTENTIAL FOR IMPROVING FREEZING STRESS TOLERANCE OF WILD POTATO GERMPLASM BY SUPPLEMENTAL CALCIUM FERTILIZATION Sandra E. VegaS,John B. Bamberg 2, and Jiwan P. Palta : Abstract ...
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Control of tuber sprouting in long-term potato storage is an important priority in potato industry. Chemical sprout inhibitors are effective in reducing sprouting but are environmentally unfriendly. Researchers have been examining... more
Control of tuber sprouting in long-term potato storage is an important priority in potato industry. Chemical sprout inhibitors are effective in reducing sprouting but are environmentally unfriendly. Researchers have been examining essential oils from plants ...
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Breeding and selection for frost resistant potatoes with high yield and good quality is very promising. This has been demonstrated in a frost resistance breeding program conducted at the International Potato Center, Lima, Peru. Yield... more
Breeding and selection for frost resistant potatoes with high yield and good quality is very promising. This has been demonstrated in a frost resistance breeding program conducted at the International Potato Center, Lima, Peru. Yield trials were conducted using selected frost resistant clones at various Andean locations at elevations from 3,200 to 3,900 meters (14). During the growth season, several
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The stolon length and percentage of tubers with tuber roots were compared for eight cultivars ofSolanum tuberosum L. over two growing seasons. Although stolon lengths varied considerably within cultivars, there were significant... more
The stolon length and percentage of tubers with tuber roots were compared for eight cultivars ofSolanum tuberosum L. over two growing seasons. Although stolon lengths varied considerably within cultivars, there were significant differences in the average stolon lengths among cultivars. The cultivars Norchip and Monona had the shortest stolons whereas Norland had the longest average stolons. The length of the stolon did not appear to be related to color type or time of tuber maturity. Since there was no significant difference in stolon length between years, stolon length appears to be a consistent genetic trait. There was no significant correlation between the stolon length and tuber size. The incidence of tuber roots also showed variation among cultivars, although there was significant variability between times of sampling. Recent studies have demonstrated that to maximize calcium uptake by tubers, the calcium must be placed around the tubers and stolons. Since stolon length determines the location of the tubers in the hill, the stolon length of different cultivars may need to be considered for fertilizer application, cultivation or hilling procedures. Thus, to get maximum benefit from supplemental calcium for Norchip and Monona, application would need to be made close to the main stem. However, in the other cultivars, the majority of the hill would have to be enriched in calcium to effectively supply calcium to the various tubers in the hill.
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Research Interests: Carbon Dioxide, Photosynthesis, Biomass, Potato, Life Support Systems, and 15 moreGrowth, Darkness, Crop Production, Relative Humidity, Photoperiod, Harvest Index, Solanum Tuberosum, Spacecraft, Dry Matter, Fresh Weight, Plant Leaves, Dry Weight, Horticultural production, cross sectional area, and Energy Requirement
Uniconazole (UCZ) can control tree size by suppressing tree growth. Growth control of one year-old `Haralred' on MAC 9 `MARK' (dwarf) and EMLA 7 (semidwarf) rootstock was evaluated in the greenhouse. Uniconazole (65 or 130 mg/L)... more
Uniconazole (UCZ) can control tree size by suppressing tree growth. Growth control of one year-old `Haralred' on MAC 9 `MARK' (dwarf) and EMLA 7 (semidwarf) rootstock was evaluated in the greenhouse. Uniconazole (65 or 130 mg/L) was sprayed 0, 1, 2 or 3 times at 3 week intervals. Total shoot growth was inhibited 31% and 24% on `MARK' and EMLA 7 rootstock, respectively, with 130 mg/L. Rootstock and scion diameter and number of leaves per tree were not affected by UCZ. Total leaf area on `MARK' rootstock increased when UCZ was applied once at 65 or 130 mg/L. On EMLA 7 two 130 mg/L sprays resulted in 22% less total leaf area compared to the control. UCZ applied three times reduced specific leaf weight on EMLA 7 trees 12% compared to the control. Branch angle was increased proportional to UCZ applications on semidwarf rootstock from 40° to 47°, and decreased on dwarf rootstock from 47° to 39°. Stomatal conductance increased 43% on `MARK' with 130 mg/L UCZ applied two...
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Plots set up on a commercial seed farm were supplemented with 0 or 168 Ca/ha supplied from liquid calcium nitrate at 3 and 6 weeks after hilling (84 kg Ca/ha per application). Paired measurements of tuber medullary tissue Ca concentration... more
Plots set up on a commercial seed farm were supplemented with 0 or 168 Ca/ha supplied from liquid calcium nitrate at 3 and 6 weeks after hilling (84 kg Ca/ha per application). Paired measurements of tuber medullary tissue Ca concentration and decay severity after inoculation with Erwinia carotovora pv. atroseptica (Eca.) were taken on identical tubers from these separate plots of `Atlantic', `Superior', `Red Norland', and `Russet Burbank'. Fresh-cut seed pieces sprayed with a suspension of Eca. (108 cfu/ml) were planted in separate 1-liter containers filled with field soil maintained under two soil moisture regimes: 1) air-dry days 1–5, saturation days 6–10, field moisture capacity (FMC) days 11–18, or 2) FMC days 1–18. Containers were placed at 22C constant air temperature at the Univ. of Wisconsin–Madison Biotron. Decay severity (percent volume seed piece decay) and decay incidence (percent tubers with any decay) were rated after 18 days. Eight seed pieces per trea...
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To assess nutritional potential, pod yield, and Ca concentration of pods and foliage were determined for a snap bean population, which included sixty S1 families plus four commercial varieties. The experimental design was an 8 × 8 double... more
To assess nutritional potential, pod yield, and Ca concentration of pods and foliage were determined for a snap bean population, which included sixty S1 families plus four commercial varieties. The experimental design was an 8 × 8 double lattice, repeated at two locations (Arlington and Hancock, Wis.). Snap beans were planted in June 1993 and machine harvested in August 1993. Calcium analyses were made using an atomic absorption spectrophotometer. Significant differences were detected in pod Ca concentration and yield among the S1 families. Pod size and Ca concentration were inversely correlated (R2 = 0.88). Distinct differences between the locations were not observed, and higher Ca genotypes remained high regardless of location or pod size. Low correlation (R2 = 0.21) between pod and leaf Ca concentration was found. Pods of certain genotypes appeared to have the ability to import Ca more efficiently than others, but this factor was not related to yield.
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Two commercial snap bean (Phaseolus vulgaris L.) cultivars (Hystyle and Labrador) that differ in pod Ca concentration were grown aeroponically to assess physiological factors associated with these differences. Xylem flow rate, Ca... more
Two commercial snap bean (Phaseolus vulgaris L.) cultivars (Hystyle and Labrador) that differ in pod Ca concentration were grown aeroponically to assess physiological factors associated with these differences. Xylem flow rate, Ca absorbed, and Ca concentration in sieve sap and pods (all and commercial size no. 4) were measured. Flow rate, Ca absorption and pod Ca concentration, but not sap Ca concentration, differed between cultivars, and this suggests that genetic variability in pod Ca concentration is caused mainly by differences in flow rate, rather than differences in sap Ca concentration. `Hystyle' showed 1.6 times greater flow rate, 1.5 times greater pod Ca concentration, and 1.7 times greater Ca absorbed than `Labrador'. Flow rate correlated positively with Ca absorbed (R = 0.90), Ca concentration in pods of size no. 4 (R = 0.55), and total pods (R = 0.65). Plant maturity influenced sap Ca concentration and Ca translocated increased as plant matured. These results pro...
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Common Scab of Potato, a disease caused by the bacterium Streptomyces scabies continues to be a serious problem for growers in the north central and other potato producing regions of the United States. This disease adversely affects the... more
Common Scab of Potato, a disease caused by the bacterium Streptomyces scabies continues to be a serious problem for growers in the north central and other potato producing regions of the United States. This disease adversely affects the marketable yield of potato crops, either through occasional reduction of gross yield, or more importantly, reducing the skin quality. The incidence and severity of scab varies with location and season. Cropping history, soil moisture, and soil texture are largely responsible for this variability (Haynes et al. 1997). Lowering the soil pH under 5.2 has been proposed to reduce scab problem, but this practice will greatly reduce the choices of crops that can be used in rotation with potatoes. Furthermore, other species, Streptomyces acidiscabies produces scab diseases at pH lower than 5.2 (Bonde and McIntyre, 1986; Lambert and Loria, 1989).