Potato

Mütevazi bir ürün olarak bilinen patates bitkisinin anavatanı Peru ve Bolivya And dağlarıdır. 1800 yıl öncesine kadar da İnka medeniyeti tarafından yetiştirilmekteydi. İnkalar yüzyıllarca patatesle iç içe bir yaşam tarzına bürünmüş olsalar da 16. yüzyılda patates bitkisi istilacı İspanyol medeniyeti tarafından Avrupa kıtasına getirilmiştir. 17. yüzyılın sonlarına doğru gelindiğindeyse patates bitkisi tüm Avrupa kıtasına yayılmış ve özellikle fakir insanlar tarafından yetiştirilmeye başlanmıştır. İrlanda adasında da aynı durum söz konusudur. Patateslerin tohumlardan ziyade yumru köklerinden yaygın bir şekilde yayıldığı göz önüne alındığında, ülke genetik olarak aynı patates bitkileri ile doludur. 1840'lı yılların başlarında, İrlanda nüfusunun neredeyse yarısının sadece diyet için patates ile ilintili yiyeceklere karşı bağımlı hale geldiği tahmin edilmektedir. Patates bitkisinin özelliklerine bakıldığında toprak altında kalırken geç kuruması ve ıslak zeminde durması doğal ömrünü uzatmaktadır. Amerika kıtasından getirilen patojenler daha önce İrlanda'ya getirilmiş olan orijinal patateslere nazaran daha çok farklılık göstermeye başlamıştır. İrlanda'daki patates tarlaları şiddetli kuraklık altında kalmaya başlamış ve her yıl rekoltenin yarısı ancak karşılanmaya başlanmıştır. 1846-1849 yılları arasında patates kıtlığı bir hayli baş göstermeye başlamış ve İrlanda halkı büyük bir kıtlık felaketi ile karşı karşıya kalmıştır. Söz konusu bu büyük kıtlığın sonuçları gittikçe korkunç bir hal almaya başlamıştı. Patates yemekleri bulmak artık gittikçe zor hale gelmeye başlamıştır. Bu arada baş göstermeye başlayan açlık ve kıtlık özellikle köylüleri etkilemeye başlamış topraklarını kiralamış oldukları zenginlere kira bedellerini ödeyememe durumuna gelmişlerdir. Bundan dolayı birçok tarım işçisi yer değiştirmeye başlamış olup daha sonra birçoğu Amerika Birleşik Devletleri'ne göç etmeye başlamıştır. Ayrıca yaşanan kıtlık felaketi neticesinde yaklaşık 1 milyon İrlandalı yaşamını kaybetmiş 1 milyonu aşkın insan ise daha önce de belirtildiği üzere çeşitli ülkelere ve kıtalara göç etmeye mecbur kalmıştır. Bu olaylar yaşanırken Britanya hükümeti yaşanan bu kıtlık felaketine karşı kayıtsız kalması İrlandalıları öfkelendirmiş ve 1922 yılında İrlanda hükümeti kurularak bağımsızlık elde edilmiştir. 1922 senesinde Bağımsızlık kazanan İrlanda nüfusu ise 1840 yılındaki nüfusunun ancak yarısı kadar idi. Bu yıldan itibaren İrlanda Devleti tarafından 1846-1849 yılları arasında yaşanmış olan kıtlık felaketini her yıl çeşitli etkinlikler düzenleyerek anılmaktada olup olayın izlerini taşıyan şehirlerde ise açık hava müzeleri açılmıştır.

This article investigates the markup pricing behaviour of U.S. exporters of agricultural products. Agricultural products studied are feed, flour, frozen potatoes, frozen orange juice, five categories of beef, five categories of pork, and two categories of chicken. The popular pricing-to-market (PTM) approach of Krugman (1987) is used to examine market power and imperfect competition for the markets under study. The

Protein concentrates prepared by expanded bed adsorption (EBA) chromatography from industrial potato juice (PJ) were analysed for chemical composition, color, enzyme activities, thermal properties and selected functional properties (solubility and emulsifying stability). Two EBA multi-modal resins, MIMO I-45 and MIMO 1300 (UpFront Chromatography), were employed under various pH conditions resulting in four potato protein concentrates, AD. Concentrate B contained an electrophoretically pure protease inhibitor fraction (20-21 kDa), whereas concentrate A, C and D contained both patatin (41 kDa) and protease inhibitors. The potato protein concentrates were explored for the presence of transitions from native to denatured states using differential scanning calorimetry (DSC). Concentrate C had lower heat of transition (DH) and T-onset than the other concentrates. The concentrate containing protease inhibitors exhibited the highest denaturation temperature and enthalpy. All concentrates differed significantly (P < 0.05) in color brightness, with concentrate B and D emerging as the brightest. The solubility of the concentrates was evaluated at pH 6 and pH 4.5. All concentrates had lower solubility at pH 4.5 than at pH 6 (70-80%). The stability of emulsions (1% protein, 20% oil, 0.08% xanthan gum) against creaming was analysed with a new method based on the Single electrode Capacitance Probe (SeCaP) technology. Small differences among concentrates were observed by the new SeCaP method.

In photosynthetic tissues superoxide dismutase (SOD) plays an important role by scavenging the superoxide radical whose production is an usual reaction in chloroplast thylakoids. To test the differential response of SOD, two Andean potato species differing in frost resistance, Solanum curtilobum (frost resistant) and Solanum tuberosum (frost sensitive), were subjected to methyl viologen-mediated oxidative stress and polyethylene glycol (PEG)-induced water stress. A significant increment (approximately two-fold) in total SOD and FeSOD activity, which occupied about 50% of the total activity, was found when leaves of S. curtilobum were exposed to water stress. In contrast, the SOD activity in leaves of S. tuberosum remained unchanged. The exposure of leaves of S. curtilobum to oxidative stress increased total SOD and FeSOD activity by 350%. High correlation between SOD activity and the F v /F m ratio under both PEG induced water stress and MV-mediated oxidative stress was observed. This suggests that SOD can protect PSII from superoxide generated by oxidative and water stress. The higher SOD activity could be an important mechanism to explain why some natives Andean potato like S. curtilobum are more resistant to abiotic stresses than S. tuberosum.

Two experiments were conducted to evaluate the effects of feeding different sources of easily fermentable carbohydrates to entire male pigs during the last weeks before slaughter. In Exp. 1, 48 entire male pigs (21.8 and 100.5 kg initial and final body weight, respectively) were used to evaluate the effect of adding 0, 3, 6, or 9% chicory inulin (containing 70% inulin) to diets during the last 30 days before slaughter on skatole concentration in the hind-gut and adipose tissue and on the composition of microbiota and mucosa morphology in the hind-gut. In Exp. 2, 66 entire male pigs (31.0 and 112.0 kg initial and final body weight, respectively) were used to evaluate the effect of adding 20% raw potato starch to diets as a top dressing or adding increasing levels of potato starch (0, 5, 10, 15%, and 20%) to diets prior to pelleting during the last 14 days before slaughter on skatole concentrations in hind-gut and adipose tissue and on the composition of microbiota in the hind-gut. Results from Exp. 1 showed a significant reduction in skatole levels in colon and rectum with increasing dietary levels of inulin (linear, P ≤ 0.002). In these diets there was also a reduction of enterobacteria counts in colon descendens (linear, P = 0.04) and rectum (linear, P = 0.02), and a tendency towards reduced levels of Enterococcus spp. in colon descendens (linear, P = 0.09) and rectum (linear, P = 0.08). Results from Exp. 2 showed that adding raw potato starch as a top dressing reduced skatole levels in rectum and adipose tissue compared with the control, while adding increasing levels of potato starch to diets prior to pelleting did not affect skatole levels. Adding potato starch as a top dressing or to diets before pelleting did not affect the cultured bacteria in the hind-gut of pigs. Feeding inulin or potato starch did not affect mucosal epithelial cell counts in the cecum or colon in Exp. 1 and Exp. 2, respectively. In conclusion, feeding increasing levels of chicory inulin to entire male pigs during the last period before slaughter reduced the level of skatole in the distal intestine and in adipose tissue, feeding pelleted diets containing up to 20% potato starch had no effect, while feeding 20% raw potato starch as top dressing reduced the level of skatole in the distal intestine and the adipose tissue of the entire male pigs.

Severe late blight epidemics in Tunisia in recent years prompted population studies on the pathogen responsible for this disease, Phythophthora infestans. Characterisation of 165 Tunisian P. infestans isolates collected from 2006 to 2008 was performed for the mating type and mt haplotype, while subsets were analysed for metalaxyl sensitivity (n=65), virulence on differential set of 11 R genes of Solanum demissum (n=31), aggressiveness on cv. Bintje (n=36) and measurement of the radial growth on agar medium at three temperatures (n=38). Most isolates from potato and all isolates from tomato had the A1 mating type. The A2 mating type was detected in the northeast and northern areas, but not in the northwest. All the A2 mating type isolates were metalaxyl resistant and seem to be part of a new generation of the P. infestans isolates which are more aggressive, with more complex races, and tolerant to higher temperatures. The increased severity of epidemics during 2006 to 2008 can be attributed to favourable weather conditions during growing seasons, adaptation of new genotypes, widespread phenylamide resistance in potato production regions and most probably incorrect spray programmes. In contrast to the presence of complex pathotypes in two major potato crop regions (north-east and northern areas), the

Abiotic and biotic host-plant stress, such as desiccation and herbivory, may strongly affect sap-sucking insects such as aphids via changes in plant chemicals of insect nutritional or plant defensive value. Here, we examined (i) water deprivation and (ii) defoliation by the beetle Leptinotarsa decemlineata as stresses indirectly affecting the aphid Macrosiphum euphorbiae via its host plant Solanum tuberosum. For plant-induced stress, aphids were reared on healthy vs. continuously stressed potato for 14 days (no watering; defoliation maintained at $40%). Aphid performance under stress was correlated with metabolic responses monitored by profiling of the aphid proteome. M. euphorbiae was strongly affected by water stress, as adult survival, total aphid number and biomass were reduced by 67%, 64%, and 79%, respectively. Aphids performed normally on defoliated potato, indicating that they were unaffected or able to compensate any stress induced by plant defoliation. Stressed aphid proteomes revealed 419-453 protein spots, including 27 that were modulated specifically or jointly under each kind of host-plant stress. Reduced aphid fitness on water-stressed plants mostly correlated with modulation of proteins involved in energy metabolism, apparently to conserve energy in order to prioritize survival. Despite normal performance, several aphid proteins that are known to be implicated in cell communication were modulated on defoliated plants, possibly suggesting modified aphid behaviour. The GroEL protein (or symbionin) of the endosymbiont Buchnera aphidicola was predominant under all conditions in M. euphorbiae. Its expression level was not significantly affected by aphid host-plant stresses, which is consistent with the high priority of symbiosis in stressed aphids. r

The effects of normal and controlled atmosphere combinations on tuber components responsible for acrylamide formation were studied during prolonged storage at 9±1 °C using the tubers of “Agria” and “Russet Burbank.” The effects of low-dose irradiation (50, 200 Gy) prior to normal atmosphere storage were also studied. There was only a limited increase in the concentrations of sugars during 6 month of storage under normal atmosphere conditions. Low-dose irradiation slightly decreased the rate of sweetening in the tubers. The potential of acrylamide formation remained almost the same; however, the loss of firmness became clearer during 6 month of storage under normal atmosphere conditions. Controlled atmosphere storage in which O2 was deficient to a sufficient respiration increased the concentrations of sugars, and thus, the potential of acrylamide formation in potatoes upon frying at 170 °C for 10 min. The sum of glucose and fructose concentrations showed a good correlation (r 2∼0.90) with the potential of acrylamide formation for both cultivars.

Ready-to-eat potato-soy snacks were developed with high temperature short time air puffing process followed by oven toasting for increasing crispness. Oven toasting experiments were conducted with varying temperature (85.86-114.14°C) and time (12.69-35.31 min) based on central composite rotatable design. The final product was evaluated in terms of quality attributes such as crispness, moisture content, ascorbic acid loss, colour (L and DE) values and overall acceptability. The optimum product qualities in terms of crispness (38.7), moisture content (3.35%, db), ascorbic acid loss (20.87%, db), L value (52.03), DE (8.60) and overall acceptability (7.8) were obtained at temperature of 104.4°C and time of 27.9 min.

Summary. In this study, calli were obtained from in vitro grown potato stem or leaf segments cv. Cosima on MS medium containing 2,4-D, NAA, kinetin and yeast extract. After three subcultures, well grown calli were exposed to UV-C radiation with approximately 6.24 µmol photon/m2/s for 30 min three times at an interval of 2 weeks. Somaclonal variation induced by UV-C

Strain selections of Russet Norkotah have been selected for enhanced vigor and high yield. In addition, they exhibit less severe expression of disease symptoms in the presence of Verticillium dahliae, a soil-borne fungal pathogen that causes Verticillium wilt. However, this apparent resistance may be due to later maturity in the strain selections. This study was designed to compare the levels

Effects of nitrogen @ 20, 40, 60 and 80 meq in combination with potassium @ 10, 20, 30, 40 and 50 meq on in vitro tuberization of potato were evaluated to find out the optimum concentration of nitrogen and potassium for developing a standard protocol for in vitro tuberization of a popular variety Diamant. Microtuberization was delayed with increasing rate of nitrogen. Number of microtubers were reduced with an increase in total nitrogen but the average weight of microtubers increased with an increase in nitrogen level up to 60 meq. The number and size of microtubers increased with an increase in potassium up to 40 meq. Concentration of nitrogen at 60 meq and potassium at 40 meq in MS medium gave rise to microtubers of large size

Nb is a single dominant gene in potato that confers hypersensitive resistance to potato virus X (PVX) isolates from strain groups 1 and 2. Genetic and molecular analyses showed that Nb is located on the upper arm of chromosome V and forms part of a cluster of resistance genes encoding specificities to many different pathogens. We describe the genetical localisation of molecular markers tightly linked to the Nb locus and the development PCR-based markers suitable for isolation of the Nb resistance gene by positional cloning. A bulked segregant approach was applied to identify polymorphic AFLP markers tightly linked to the Nb locus. These markers were mapped in a population of segregating S1 progeny (1,300 plants) from a self-pollinated potato cultivar, Pentland Ivory. From this analysis, Nb was placed in an interval of 0.76 cM, flanked by the AFLP markers GM339 and GM637. Recombinant PVX strains carrying different combinations of avirulence genes were used in biological assays to show that Nb was also present in potato cv. Cara but was masked by the extreme PVX resistance conferred by the Rx gene. PCR-based screening of a Cara genomic BAC library with markers closest to the Nb locus identified a new marker tightly linked to Nb.

The production of strong healthy plant material ex vitro is essential for an efficient seed potato production programs. Current study shows an applicable method for enhancing performance of potato plantlet subsequent in vitro phase. Using of ventilation and omitting sucrose from the nutrient medium (photoautotrophic culture) resulted in strong plantlets with higher fresh and dry weight performed better during acclimatization. Furthermore, Using of culture media contain macronutrients based on potato leaves macronutrients concentrations produced vigorous plantlets. Varietal differences were recorded between the two tested varieties Cara and Diamant. To obtain healthy start material for seed potato program this study recommend the use of in vitro photoautotrophic culture and modified nutrient media based on potato leaf macronutrient concentrations.

Bacillus thuringiensis delta-endotoxins (DET) possess aphidicidal activity in an artificial diet bioassay. Crystalline preparations of CrylIA, CrylIIA and CrylVD solubilized in a slightly alkaline sucrose/amino acid diet clearly imparted toxicity toward adults of potato aphid, Macrosiphum euphorbiae (Thomas) (Homoptera: Aphididae) after 4-5 days of continuous feeding. No obvious feeding deterrence was noted in these assays, as copious honeydew was produced and aphids often died in a feeding position. CrylIIA which was solubilized in aphid diet, but filtered to remove spores or crystalline toxin lacked aphidicidal activity. Spores from an acrystalliferous strain (EG2205) were not toxic by themselves at 7.75 x 105 spores/ml aphid diet, but did restore toxicity to the filtered CrylIIA solution. Therefore, low levels of spores may be very effective in concert with DET for aphicidal activity. Results also clearly demonstrated that a suspension of crystalline CrylIIA alone, without spores, exhibited toxicity. Therefore, DET may be more toxic to the aphids when imbibed as a fine suspension, perhaps indicating the need for slow solubilization into the aphid midgut.

The aim of this study has been to determine the indirect and direct effects of farmyard manure and sewage sludge composts, produced in the northeastern part of Poland, on the content of 1 mol HCl⋅dm-3 soluble forms of zinc and copper in soil. In 2004-2007, a field experiment was carried out at the Experimental Station in Ba³cyny near Ostróda. The experiment was established on proper grey-brown podzolic soil originating from light boulder clay, which was rich in P, moderately abundant in K and low in Mg. It comprised a four-field crop rotation system (potato, spring barley, winter oilseed rape and winter wheat. The design of the experiment, set up according to the random block method, involved 8 objects (2 x 4): 1) farmyard manure, 2) compost (sewage sludge + straw), 3) dried and granulated sewage sludge, 4) composted sewage sludge. The composts and FYM were introduced to soil once (in 2004) at a rate of 10 t d.m.⋅ha-1 or 2 × 5 d.m.⋅ha-1 (under potato and winter oilseed rape). In 2004, nitrogen in the soil enriched with natural fertilizers was balanced to 150 kg⋅ha-1 according to the N-total content. In 2005, soil cropped with spring barley received only mineral fertilization, whereas winter oilseed rape received the second rate of organic fertilizers (in the series consisting of 2 × 5 d.m.⋅ha-1) and nitrogen was balanced to 120 kg⋅ha-1. In 2006, soil under winter wheat received only mineral fertilization. Prior to the establishment of the experiment, soil, manure and compost samples were taken. Having been averaged, the samples were subjected to determination of their content of Cu and Zn in 1 mol HCl dm-3. The soil, whose reaction was 5.04 in 1 mol HCl dm-3 , was moderately abundant in available zinc and low in copper. After four years of the trials, the levels of available forms of copper and zinc in the soil fertilized with sewage sludge

A two-year field study conducted at the Potato Research Centre in Fredericton, New Brunswick, demonstrated a quantifiable residency time for Bacillus thuringiensis (Bt) susceptible adult Colorado potato beetles (Leptinotarsa decemlineata) in a Bt-transgenic potato field. Fifty percent of Bt-susceptible beetles released in a transgenic Russet Burbank (NewLeafTM) potato plot were recaptured 4 to 7 days after release compared to 7 to 11 days for beetles released in a non-transgenic control plot. Beetles survived for long periods of time (up to 31 days) on transgenic potatoes in spite of the crop&#39;s toxicity. A significant number of beetles dispersed from transgenic plots. Twenty-five and 30% of the beetles released in the Bt-transgenic plot were recaptured in border rows or trench traps outside the plot indicating a high level of dispersal activity. The long residency time and the high level of dispersal activity could increase the chances of development of a Bt-resistant beetle pop...

La papa tiene una alta sensibilidad a los excesos y deficiencias de humedad en el suelo. Con la aplicación del modelo basado en el concepto grados día (°D), se obtiene un pronóstico del riego más preciso debido a que este modelo se ajusta automáticamente a las variaciones climáticas locales, lo cual permite determinar con mayor precisión el inicio de cada etapa fenológica del cultivo y sus correspondientes necesidades hídricas, incrementando así las eficiencias de riego. Esta investigación se realizó durante dos años agrícolas para el ciclo otoño-invierno (2005-2006 y 2006-2007) en el norte de Sinaloa, contando con un total de 23 parcelas (746.54 ha) de las cuales 12 fueron experimentales aplicándoles el modelo basado en el concepto grados día y las 11 restantes fueron testigo aplicándoles el sistema de pronóstico del riego en tiempo real (SPRITER-FAO) que utilizan algunos de los módulos de riego del Distrito 075 Río Fuerte. De esta forma se compararon las láminas de riego aplicadas (Lra) y requeridas (Lrr) por las dos vías de pronóstico, obteniendo la eficiencia, así como la variación en el número de riegos debido a la variabilidad climática. Para el ciclo 2005-2006 y 2006-2007, se obtuvo en parcelas experimentales de 7 y 9 Mg ha-1 más de rendimiento con respecto a las parcelas testigo, respectivamente, así como un 22.2 y 17.5% de mayor eficiencia en los riegos aplicados.

The objective of this study was to develop a simple mechanistic model to predict the magnitude of ABA signalling ([X-ABA]) of potatoes (Solanum tuberosum L.) exposed to partial root-zone drying (PRD). Potatoes were grown in pots in a glasshouse with the roots split equally between two soil columns. At tuber initiation stage, plants were subjected to three irrigation treatments: (1) both soil columns were fully irrigated (FI) daily to a volumetric soil water content (θ) of 18.0%; (2) PRD, in which one soil column was irrigated daily to 18.0% while the other was allowed to dry, and the irrigation was shifted between columns when the θ of the drying soil column had decreased to 7–8%; (3) non-irrigation (NI), where irrigation was withheld after onset of treatments and lasted for 5 days until θ had decreased to 7%. In the PRD plants, the fraction of soil water extraction (FSWE) by the dry roots declined exponentially with declining soil water potential (Ψsoil-dry); however, after shifting of irrigation, the previously dried roots immediately recovered the full capacity of water uptake. During the first PRD drying cycle, FI plants had the highest stomatal conductance (gs), and followed by PRD plants and NI plants had the lowest gs. Photosynthesis (A) was similar for FI and PRD plants, and was significantly lower for the NI plants only on 3–4 days after treatment. In the NI plants, a linear relationship between Ψsoil and [X-ABA] was obtained. Based on these relationships, a simple model predicting [X-ABA] in the PRD plants ([X-ABA]PRD) was developed. Assuming that a constant [X-ABA] of 115 nM (similar to that found in the FI plants) originated from the wet roots; the simulation results indicated that irrigation should be shifted between the two sides when Ψsoil-dry had decreased to ∼−80 kPa, and [X-ABA]PRD had reached a peak of ca. 150 nM. However, the [X-ABA]PRD predicted by the model was significantly lower than the measured value; whilst a simple average of [X-ABA] from the wet and the dry soil columns based on the [X-ABA]–Ψsoil relationship better predicted [X-ABA]PRD.

The content of reducing sugars and asparagine, responsible for the formation of acrylamide, was determined in eight Indian potato varieties. Among these, Kufri chipsona-2 and Kufri lavkar showed the lowest level of reducing sugar (680.68 ± 56.50 mg/kg) and asparagine (2074.36 ± 122.27 mg/kg), respectively. The acrylamide content in potato chips prepared from Kufri chipsona-2, the variety that is used commercially in India for making potato chips was also the lowest. Irradiation of this variety of potatoes at the sprout inhibition dose of 60 Gy and subsequent storage for six months showed a 10.7% lower content of reducing sugars at both 14 and 4 °C. The acrylamide content was 8.41% and 6.95% lower in chips from irradiated potatoes stored at 14 and 4 °C than the corresponding non-irradiated controls. The colour of the chips was also better in irradiated potatoes as judged from the L∗ and a∗ values.► Indian varieties of potatoes were screened for their ability to form acrylamide. ► Irradiation reduces sprouting, and hence the reducing sugars. ► Irradiated potatoes showed lower content of acrylamide in potato chips.

Potato is the fourth major food crop after rice, wheat and maize in Bihar. It occupies less than 5% of net sown area with production only 4 th after rice, wheat and maize. Potato a short duration crop has special significance since it gives exceptionally high yields/unit area/unit time and has high nutritional value to sustain burgeoning population and ward off hunger and malnutrition. Potato produces more food, edible energy and edible protein per unit area and time as compared to any other food crop. Potato provides excellent opportunities in rasing the income of the farmers as it has capacity to yield 5-10 times more than cereals, pulses or oilseeds. Efficient marketing is crucial for a successful diversification and commercialization of potato and accelerated farmer income growth.

Bronx, NY 10458-5126 U.S.A. tubérculos sin procesar. Las concentraciones de estos minerales disminuyó más drásticamente para chuño blanco comparado con chuño negro. El efecto de los cuatro variantes de congelado-secado sobre el contenido de materia seca, hierro, calcio y sodio del chuño varió dependiendo del proceso y/o cultivar.

The research was carried out to assess the effect of vermicompost and tuber size on the changes of TSS (total soluble solids), sucrose (non-reducing sugar) content, and skin color of potato under ambient storage condition. Potato variety BARI TPS-1 was used as an experimental crop. The experiment was consisted of two factors, i.e., factor A:-Vermicompost level (Vm1-4): Vm1: 0 t ha-1 (control), Vm2: 3 t ha-1 , Vm3: 6 t ha-1 and Vm4: 9 t ha-1 ; factor B:-Tuber size (T1-5): T1: 5-10 g, T2: 10-20 g, T3: 20-30 g, T4: 30-40 g and T5: >40 g. The research exhibited that vermicompost had a significant effect on most of the quality contributing parameters investigated under the experiment. Results exhibited that processing quality parameters increased with increasing vermicompost level irrespective of tuber size. Among the twenty (20) treatment combinations, vermicompost at the rate of 9 t ha-1 with tuber size >40 g produced the minimum total soluble solids (4.55% Brix), minimum sucrose (0.2947 mg g-1 FW) and maximum skin color (L* 67.38, a* 15.38, b* 26.60). In respect of ambient storage condition total soluble solids (TSS), sucrose slowly increased with increasing storage time up to 40 days after storage (DAS) and finally became non-suitable for both table and processing purpose; while skin color decreased with increasing storage time. Therefore, the study suggests that potato growers may use vermicompost for improving processing quality of potato varieties and can store potato up to 40 DAS at ambient storage condition.

This investigation evaluated some new (Preflo) and existing commercially available (Starch 1500, Star Tab) modified starches as direct compression excipients. Preflo corn starches (CH-10, CH-20, CH-30) and Preflo potato starches (P-250, PI-10, PJ-20) were evaluated and compared with respect to their pharmaceutical properties such as particle size, density, flowability, friability, and compression properties. Preflo starches showed a high bulk density and good flowability. Preflo corn starches and Star Tab formed harder tablets than Preflo potato starches and Starch 1500. Data from the Athy-Heckel plots indicated that the Preflo starches are soft materials and, unlike Starch 1500, undergo plastic deformation. Tablets containing acetaminophen were also compressed with the starches and disintegration and dissolution studies were conducted. Starch 1500 tablets disintegrated in 3.5 min, whereas none of the Preflo starch tablets disintegrated in 30 min. While complete acetaminophen releas...

BACKGROUND: Acrylamide is a probable human carcinogen produced during food preparation, including frying of potato products. The aim of this study was to investigate the impact of seasonal variation on tuber composition and its acrylamide generation potential.RESULTS: The chemical composition of potato varieties used respectively for French fry (Bintje and Ramos) and crisp (Lady Rosetta and Saturna) production was studied throughout a storage period of 9 months during two growing seasons (2003 and 2004), in addition to their acrylamide generation potential during preparation of French fries. A significant impact of variable climatological conditions on the reducing sugar, dry matter, total free amino acid and free asparagine contents of tubers was observed. Exceptionally warm summers gave rise to a lower reducing sugar content (expressed on a dry matter basis) and thus a lower susceptibility to acrylamide generation during frying.CONCLUSION: It cannot be excluded that potato growers and the potato-processing industry are confronted with some harvests that are more prone to acrylamide generation than others owing to climatological variability, thus confirming the importance of a multifactorial approach to mitigate acrylamide generation in potato products. Copyright © 2007 Society of Chemical Industry

The effect of snowdrop lectin (Galanthus nivalis agglutinin; GNA) expression on hostplant preference was examined with a two-choice disc test. Discrimination between a transgenic potato [Solanum tuberosum (Solanaceae)] capable of synthesizing GNA, and an isogenic cultivar, was studied under laboratory conditions using the glasshouse potato aphid Aulacorthum solani (Hemiptera: Aphididae), the onion thrip Thrips tabaci (Thysanoptera: Thripidae), and the two-spotted spider mite Tetranychus urticae (Acari: Tetranychidae).

Salinity is one of the main environmental stresses, and it affects potato growth and productivity in arid and semiarid regions by disturbing physiological process, such as the photosynthesis rate, the absorption of essential nutrients and water, plant hormonal functions, and vital metabolic pathways. Few studies are available on the application of combined nanomaterials to mitigate salinity stress on potato plants (Solanum tuberosum L. cv. Diamont). In order to assess the effects of the sole or combined application of silicon (Si) and potassium (K) nanoparticles and biochar (Bc) on the agro-physiological properties and biochemical constituents of potato plants grown in saline soil, two open-field experiments were executed on a randomized complete block design (RCBD), with five replicates. The results show that the biochar application and nanoelements (n-K and n-Si) significantly improved the plant heights, the fresh and dry plant biomasses, the numbers of stems/plant, the leaf relat...

To detect soil changes related to vegetation and fertility restoration in a long fallow agricultural system of the Venezuelan Andes, 32 soil (A horizon, 0–15cm depth) and litter characteristics were studied in plots at different stages of the fallow-cultivation cycle. Four sectors of the valley were sampled, each one including seven plots: recently ploughed after a long fallow period; 1

The production of potatoes has become important in Europe, especially since the 19th century. Since 1850 the yield of ware potatoes increased in The Netherlands from approximately 10 t ha-1 to the present level of 45 t ha-1. This was achieved by various improvements in production techniques. Several breakthroughs were accomplished in breeding for host resistance against pathogens. The current use of pesticides (nematicides, herbicides, fungicides, etc.) is high in potato production, at least in The Netherlands, particularly due to the use of fumigants to control nematodes in the starch potato growing areas. The Dutch government adopted objectives with respect to general reductions in the use of pesticides and the leaching of nutrients (nitrate). Adaptations in cultural measures are required to meet these objectives and to arrive at more sustainable systems of production in the future. In this paper special attention is given to past and present problems and possibilities with respect to cyst nematodes, late blight, wart, Colorado potato beetle, nitrogen nutrition, weed control, haulm destruction and sprout suppression.

We present efficient protocols for the regeneration of fertile plants from corm explants of Hypoxis hemerocallidea Fisch. & C. A. Mey. landrace Gaza, either by direct multiple shoot formation or via shoot organogenesis from corm-derived calluses. The regeneration efficiency depended on plant growth regulator concentrations and combinations. Multiple direct shoot formation with high frequency (100% with 5-8 shoots/explant) was obtained on a basal medium (BM) supplemented with 3 mg/l kinetin (BM1). However, efficient indirect regeneration occurred when corm explants were first plated on callus induction medium (BM2) with high kinetin (3 mg/l) and naphthalene acetic acid (NAA 1 mg/l), and then transferred to shoot inducing medium (BM3) containing BA (1.5 mg/l) and NAA (0.5 mg/l). Shoot regeneration frequency was 100% and 30-35 shoots per explant were obtained. The regenerated shoots were rooted on a root inducing medium (BM4) containing NAA (0.1 mg/l). Rooted plantlets were transferred to the greenhouse. The regenerants were morphologically normal and fertile. Flow cytometric analyses and chloroplast counts of guard cells suggested that the regenerants were diploid. Efficient cloning protocols described here, have the potential not only to substantially reduce the pressure on natural populations but also for wider biotechnological applications of Hypoxis hemerocallidea-an endangered medicinal plant.

Stem nodes of the potato virus Y NTN (PVY NTN ) susceptible potato cultivar (Solanum tuberosum cv. '' Igor '') were studied to investigate whether alterations in shoot morphology caused by infection with PVY NTN are related to changes in structure and activity of the shoot apical meristem. The PVY NTN causes severe disease symptoms known as the potato tuber necrotic ringspot disease (PTNRD) in susceptible potato plants grown in the field. Although in stem node culture the symptoms are mildly expressed, in systemically PVY NTN -infected plants the shoot height stem diameter, number of leaves and the total leaf area were lower than in the healthy control plants at day 18 and 35 of culture. Histological analysis of the longitudinal sections of the shoot tip revealed that the infected plants had smaller shoot apical meristems due primarily to a lower cell number in different meristem zones. One of the most affected zones of the apical shoot meristem was the peripheral zone, the region in which leaf primordia are induced. The data is consistent in showing that the infection of potato plants with PVY NTN leads to alterations in the shoot apical meristem structure and mitotic activity. These changes are, in turn, reflected in altered overall morphology of the infected plant.

Temporal aspects and interaction effect of pungency evoked by capsaicin/chili and leading flavour attributes in model food matrices were studied. Two experiments were performed: in experiment I pure capsaicin at three levels (0.5, 25, 125 ppm) was added to various carriers (water solution, potato starch gruel and tomato soup and sauce) and in experiment II chili powder was used as irritant (0.03%, 0.08%, 0.2%) in six different model food matrices (tomato, chicken and mushroom soups and sauces). Intensity changes of pungency and 2-3 leading flavour/taste attributes were traced using Time-Intensity procedure at predetermined discrete time intervals. Most of T-I parameters of capsaicin pungency depended strongly on both, carrier complexity and capsaicin concentration. The three pairs of model soups and sauces suppressed pungency evoked by chili differently. Pungency intensity was consistently lower in sauces than in soups. Increasing chili level caused systematic but moderate or slight suppression of leading flavour attributes (more often in soups and less in sauces). Various taste quality (acidic, bitterness and saltiness) were differently affected by pungency. Quality changes and temporal migration of pungency sensation in the mouth contributed additionally to the complexity of interaction between pungency/leading flavour and taste attributes/carriers.

A collection of 241 isolates of Rhizoctonia solani obtained from potato plants grown in different areas in France was characterized for anastomosis grouping, symptomatology on tubers of different cultivars and sensitivity to three fungicides. Most isolates collected belonged to (anastomosis groups (AGs)) AG 3, but 2% and 4% of the isolates were AG 5 and AG 2-1. AG 3 and AG 2-1 isolates were mostly obtained from sclerotia on tubers, but all AG 5, some AG 3 and some AG 2-1 isolates were recovered from superficial tuber alterations, like deformations, corky or scabby lesions. Sclerotia were formed on tubers produced by healthy stem cuttings grown in soil artificially infested with AG 3, but not on tubers grown in soil infested with either AG 5 or AG 2-1. No variation in susceptibility to sclerotial formation was observed among five potato cultivars. In all cases, a large proportion of tubers showed superficial corky lesions, often associated with deformations. The proportion of tubers with lesions and deformations was highest in soil infested with AG 2-1 and significantly lower on cv. Samba in all treatments. All isolates were highly sensitive to flutolanil, iprodione and pencycuron, except the AG 5 isolates, moderately sensitive to pencycuron. These results show that, although AG 3 is the most common R. solani group on potato in France, AG 5 and AG 2-1 may be present. Isolates differed for pathogenicity. In vitro sensitivity to fungicides varied among AGs.

A two-year experiment was conducted at the Kentland Agricultural Research Farm (KARF), VA, to evaluate potato (Solanum tuberosum L.) production of 32-to 57-mm-size-range tubers (referred to hereafter as creamers) in a conservation-tillage, cover-cropping strategy. The experiments used a split-plot design in which the main-plots were cover crop treatments and the sub-plots were different potato selections. Main plot treatments included rye (Secale cereale L.), crimson clover (TrifoUum incarnatum L.), Austrian winter pea (Pisum sativum L.), rape (Brassica napus L.), oat (Avena sativa L.), rye/crimson clover mixture, rape/ crimson clover mixture, bare soil/raised beds, and bare soil/fiat beds (control). Potato selections tested were Bl145-2, B1491-5, and B1492-12 in 2000 and Bl145-2, Bl102-3, and B0811-4 in 2001. Yields in the conserva-

Early blight caused by Alternaria solani is a severe constraint in potato production. The severity of this disease has been increasing day by day for last few years in India due to changes in weather. Disease severity and area under disease progress curve (AUDPC) was recorded in each treatment plot. The early blight disease had significant negative correlation with maximum relative humidity during 2012-13 and in year 2013-14 minimum temperature was significantly correlated. The severity of early blight showed significant positive correlation with maximum temperature and highly significant positive correlations with sun shine hours in year 2013-14 in all tested treatments. The study showed that minimum temperature and rainfall revealed negative but non-significant correlation in all treatments except untreated control in year 2012-13. The maximum tuber yield 223.70 and 222.00 q/ha in first and second years, respectively, were recorded with spray of nd Fenamidone @ 0.2% at disease initiation and 2 spray of Mancozeb @ 0.25% followed by Mancozeb @ 0.25% at 15 days intervals in both respective years.

Potato production from rooted apical cuttings or from small tubers (1-20g) produced in high density beds has great potential in Asia. This is particularly important in non-traditional warrner environments. This research .was conducted to assess the feasibility of producing many smaU tubers in high density beds. A second objective compared tubers from beds with transplanted rooted cuttings and traditional seed tubers for growth and yield in the field. Tuberlet production in beds exceeded 2000/m 2 with a density of 1000 plants/m 2 under optimal growing conditions while under high temperatures only about 1.25 tuberlets/plant were pr0duced. In field experiments, transplanted cuttings yielded 20 t/ha in the mid and high elevation areas, only slightly less than tuberlets of 5-10g while at the hot site, yields were generally only 8 to 10 t/ha for both materials. Larger healthy seed tubers produced siguificantly higher yields at the low and high elevation sites. Tuberlets of 1-5g were also able to give yields of 20 t/ha in the midelevation site. These resuhs indicate that cuttings and smaU tuberlets are two ways of growing potatoes which need to be further evaluated for socioeconomic assessment by farmers.

Modern potato breeding requires over 100,000 seedlings per new variety. Main reasons are (1) the increasing number of traits that have to be combined in this tetraploid vegetatively propagated crop, and (2) an increasing number of traits (e.g., resistance to biotic stress) originates from wild species. Pre-breeding by introgression or induced translocation is an expensive way of transferring single traits (such as R-genes, coding for resistance to biotic stress) to the cultivated plant. The most important obstacle is simultaneous transfer of undesired neighbouring alien alleles as linkage drag. Stacking several genes from different wild sources is increasing this linkage drag problem tremendously. Biotechnology has enabled transformation of alien genes into the plant. Initially, transgenes were originating mainly from microorganisms, viruses or non-crossable plant species, or they were chimeric. Moreover, selection markers coding for antibiotic resistance or herbicide resistance were needed. Transgenes are a new gene source for plant breeding and, therefore, additional regulations like the EU Directive 2001/18/EC were developed. Because of a strong opposition against genetic modification of plants in Europe, the application of this Directive is strict, very expensive, hampering the introduction of genetically modified (GM) crops and the use of this technology by small and medium-sized enterprises (SMEs). Currently, GM crops are almost the exclusive domain of multinationals. Meanwhile, not only transgenes but also natural genes from the plant species itself or from crossable plant species, called cisgenes, are available and the alien selection genes can be avoided in the end product. This opens the way for cisgenic crops without alien genes. The existing EU directive for GM organisms is not designed for this new development. The cisgenes belong to the existing breeders' gene pool. The use of this classical gene pool has been regulated already in