Stored Tubers Research Articles

Identification of fungi associated with dry rot of yam under storage conditions

Dry rot of yam tubers is a disease that currently causes the greatest economic losses to small producers associated with this crop in the Colombian Caribbean, as it deteriorates the internal tissues of tubers, causing loss of its commercial value and the seeds. Currently, we are not certain about the identity of the causal agents, so this research was carried out in order to objetive collect, isolate and characterize the fungi associated with the dry rot disease of yam tubers cv. Espino in the Caribbean region of Colombia in storage conditions. This study was carried out between February and October 2019, identifying the yam-producing areas in the Colombian Caribbean region and collecting in the municipalities and sidewalks, tubers in storage. In laboratory, the associated fungi were isolated from the lesions and identified through the amplification of the ITS (Internal Transcribed Spacer) region of the ribosomal DNA, complemented by the Calmodulin and β-tubulin gene 2. A total of 56 fungi associated with lesions were isolated, which were grouped into 10 morphotypes, achieving their classification by genus and species. According to our results, the species DH2-Lasiodiplodia theobromae, DH3-Fusarium solani, and DH6-Neocosmospora rubicola were identified as the main causal agents associated to dry rot disease of yam tubers under storage conditions in the Colombian Caribbean region.

The Influence of Storage Conditions on the Biochemical Composition and Morphology of <i>Dahlia</i> Tubers

The aim of this study was to assess by means of biometric measurements and FT-IR and FT-Raman spectroscopic techniques the influence of storage conditions on the morphology and biochemical composition of Dahlia tubers. Investigated samples belong to ‘Kennemerland’ and ‘Red Pygmy’ cultivars of the Dahlia hybrida species, which were preserved over winterat 5-8 °C, 30-40% air humidity in different substrates: sand, sand and sawdust, peat and sawdust. The biometric parameters revealed that the peat and sawdust substrate is the most appropriate one for tubers storage, whereas the sand substrate is the least suitable one. The inulin signature was evidenced in all tuber samples as well as the changes of biochemical composition induced by different storage conditions. The analysis of the FT-IR and FT-Raman spectra demonstrated that the inulinaccumulation inside the tubers is favourably influenced by the sand storage, and depends on the cultivar type. Moreover, it was established that the peat and sawdust substrate favours the polyacetylene formation inside the tubers probably because it facilitates the occurrence and development of pathogens inside the tuber. It was also found that the polyacetylene concentration increased, which is associated with the plant response to the pathogen invasion, depends on the cultivar type.

Using Essential Oils to Decrease Potato Tubers Sprouting, Rotting and Insect Infestations during Storage at Ambient Temperature

Two storage experiments were carried out at El-Mansoura Horticultural Research Station, Dakahalia Governorate, Egypt, during four months of storage in summer seasons of 2013 and 2014 for studying the effect of seven treatments, i.e,. natural essential oils and selecron on storability and quality of potato tubers and reduction percentages in the infestations potato tubers moth (PTM) under Nawwala condition. These treatments such as ; clove oil, garlic oil, lemonion oil, eucalyptus oil, peppermint oil, basil oil, mixture of these oils and selecron. The obtained results revealed that all storage treatments expect, selecron and control gave different significantly in all studied characters. Using peppermint and clove oils recorded the lowest significant values of sprouting percentage, sprout weight, sprout length and weight of loss percentage in both seasons. The highest values of dry matter %, starch% and vitamin C were recorded with peppermint oil, but the lowest sugar percentage was obtained by using the same treatment during two seasons. Results indicated that the effects of essential oils and selecron under storage in Nawwala conditions on Phthorimaea operculla (Zell.) (PTM), after four months of storage, the tubers infestation in control were (48- 48.67%), while the mean reduction percentages of infestation ranged between (94.10- 98.86% and 93.23- 96.84) during two seasons of 2013/2014 respectively. Peppermint oil, eucalyptus oil, clove oil and mixture oils gave highest mean reduction percentages of infestation such as selecron. Generally, the obtained data indicated that all used oils offered the highest protection. Also, the results in laboratory showed that the effects of oil treatments on larvae PTM recorded significantly variation according to the type of oil and time of exposure which showed fatal action on the larvae of PTM. The efficacy of Peppermint oil, Eucalyptus oil, clover oil and Mixer oils were the best. The percent of mortality ranged between (76.14 and 100%) compared with selecron. Also, all oils were used effected inhibitor action on adults. The inhibition of egg laying and reduction percentages ranged between were (47.54 %and 95.02 %) of peppermint oil and galaric oils, respectively. This study recommends that it can be sprayed peppermint oil concentration at (2 cm 3 / L / ton) three times during the storage of potato tubers in Nawwala for (4 months) in order to reduce the proportion of sprouting and weight loss and rotting and get a higher percentage of dry matter, starch and less injuries Pferashh (PTM) in tubers. Finally, it could be recommended with peppermint oil, eucalyptus oil, clove oil and mixer oils were the best during storage to obtain the best characters storage and quality. These natural treatments are very safe and potent in improving storability and greatly decreasing PTM insect infection during storage conditions in Nawwala on potato tubers.

Heat stress affects carbohydrate metabolism during cold-induced sweetening of potato (Solanum tuberosum L.).

Tolerance to heat stress for retention of low-temperature sweetening-resistant phenotype in potato is conferred by insensitivity of acid invertase activity to cold induction. Heat stress exacerbated cold sweetening (buildup of reducing sugars) of the LTS (low-temperature sweetening)-susceptible potato (Solanum tuberosum L.) cultivars, Ranger Russet and Russet Burbank, and completely abolished the resistance to cold sweetening in the LTS-resistant cultivars/clones, Sage Russet, GemStar Russet, POR06V12-3 and A02138-2. Payette Russet and EGA09702-2, however, demonstrated considerable tolerance to heat stress for retention of their LTS-resistant phenotype. Heat-primed Payette Russet and EGA09702-2 tubers accumulated fourfold more sucrose when subsequently stored at 4°C, while reducing sugar concentrations also increased marginally but remained low relative to the non-heat-tolerant LTS-resistant clones, resulting in light-colored fries. By contrast, sucrose concentrations in heat-primed tubers of the non-heat-tolerant clones remained unchanged during LTS, but reducing sugars increased fivefold, resulting in darkening of processed fries. Acid invertase activity increased in the LTS-susceptible and non-heat-tolerant LTS-resistant cultivars/clones during cold storage. However, Payette Russet tubers maintained very low invertase activity regardless of heat stress and cold storage treatments, as was the case for Innate® Russet Burbank (W8) tubers, where silenced invertase conferred robust tolerance to heat stress for retention of LTS-resistant phenotype. Importantly, heat-stressed tubers of Payette Russet, EGA09702-2 and Innate® Russet Burbank (W8) demonstrated similar low reducing sugar and high sucrose-accumulating phenotypes when stored at 4°C. Tolerance to heat stress for retention of LTS-resistant phenotype in Payette Russet and likely its maternal parent, EGA09702-2, is, therefore, conferred by the ability to maintain low invertase activity during cold storage of heat-stressed tubers.

Stem blight, foot rot and storage tuber rot of sweet potato caused by Plenodomus destruens in China

In September 2014, severe stem blight, foot rot and storage tuber rot on sweet potato were observed in experimental fields in Sanmen County, Zhejiang Province, China. The causal agent was identified as Plenodomus destruens on the basis of morphological characteristics and molecular identification. In pathogenicity tests, P. destruens caused severe wilting, stem rot, and storage tubers rot symptoms similar to those observed in the field. This is the first report of P. destruens causing stem blight, foot rot and storage tuber rot on sweet potato in mainland China where sweet potato is a main crop.

Sweet potato NAC transcription factor, IbNAC1, upregulates sporamin gene expression by binding the SWRE motif against mechanical wounding and herbivore attack.

Sporamin is a tuberous storage protein with trypsin inhibitory activity in sweet potato (Ipomoea batatas Lam.), which accounts for 85% of the soluble protein in tubers. It is constitutively expressed in tuberous roots but is expressed in leaves only after wounding. Thus far, its wound-inducible signal transduction mechanisms remain unclear. In the present work, a 53-bp DNA region, sporamin wound-response cis-element (SWRE), was identified in the sporamin promoter and was determined to be responsible for the wounding response. Using yeast one-hybrid screening, a NAC domain protein, IbNAC1, that specifically bound to the 5'-TACAATATC-3' sequence in SWRE was isolated from a cDNA library from wounded leaves. IbNAC1 was constitutively expressed in root tissues and was induced earlier than sporamin following the wounding of leaves. Transgenic sweet potato plants overexpressing IbNAC1 had greatly increased sporamin expression, increased trypsin inhibitory activity, and elevated resistance against Spodoptera litura. We further demonstrated that IbNAC1 has multiple biological functions in the jasmonic acid (JA) response, including the inhibition of root formation, accumulation of anthocyanin, regulation of aging processes, reduction of abiotic tolerance, and overproduction of reactive oxygen species (ROS). Thus, IbNAC1 is a core transcription factor that reprograms the transcriptional response to wounding via the JA-mediated pathway in sweet potato.

Boeremia tuber rot of sweet potato caused by B. exigua, a new post-harvest storage disease in China

A new post-harvest storage disease was observed on sweet potato (Ipomoea batatas L.) in Zhejiang Province, China in November 2014. A species of Boeremia was constantly isolated from diseased tissues with typical symptoms of storage tuber rot. The isolates were identified as Boeremia exigua based on morphological characteristics and phylogenetic analyses of the internal transcribed spacer (ITS) region and 5.8S ribosomal DNA, the 28S large subunit ribosomal RNA (LSU) gene, the β-tubulin (TUB) gene and the actin (ACT) gene. The pathogenicity of the fungal isolates was confirmed through inoculation experiments. This is the first report of Boeremia tuber rot caused by B. exigua on sweet potato in China.

Evaluation of primary and secondary metabolites in selected varieties of potatoes.

The aim of study was to determine primary and secondary metabolites in selected varieties of potatoes. Potatoes (Solanum tuberosum L.) are good source of bioactive compounds, mainly phenols as one of the most important components. The chemical composition with reducing sugar, starch, ascorbic acid, total polyphenol and flavonoid content were analyzed in five potato varieties (Agria, Marabel, Red Anna, Picasso, Princess). Values of dry matter content ranged from 20.34 to 23.64%. In terms of tubers storage, its content above 20% is required. The highest level of starch was detected in variety Princess (16.82%). The lowest reducing sugar content was recorded by variety Marabel (0.08%). Similarly, low values reached varieties Princess (0.12%), Agria (0.14) and Red Anna (0.16%). These would be appropriate to use for food processing and for production of fried potato chips or fries. Variety Red Anna reached the highest amount of vitamin C (73.72 mg.kg-1). The lower levels of this vitamin showed tubers of varieties Picasso (35.02 mg.kg-1) and Princess (36.89 mg.kg-1). The antioxidant activity was measured with radical scavenging assays using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical as well as phosphomolybdenic assay. Potato varieties contained high levels of total polyphenols (0.474 – 1.550 mg GAE per dry weight) and flavonoids (1.407 – 15.933 μg QE per dry weight). The consumption of potatoes can provide nutritional value along with antioxidant potential that can be helpful for proper functioning of the body physiological systems. Statistical evaluation by the single factor analysis of variance detected high significant impact of variety on the content of all the analytical parameters in evaluated varieties of potato tubers.

Impact of ethylene and 1-MCP on sprouting and sugar accumulation in stored potatoes

Long term storage of potato tubers allows year round availability of the crop but is limited by sprouting. Continuous exposure to ethylene during storage prolongs storage life of potatoes by suppressing sprouting, yet there is a lack of information on whether continuous ethylene treatment is required throughout storage. Potato cvs. Saturna and Russet Burbank were stored at 6°C under four ethylene treatments (viz. continuous ethylene (10μLL−1), continuous air, transfer from air to ethylene after first indication of sprouting and vice versa) for thirty weeks in 2008–2009 (Year 1). In Year 2 (2009–2010), tubers were stored under the same treatments and duration as in Year 1, with the addition of 1-MCP (1μLL−1) applied for 24h at harvest or at first indication of peeping. Samples were taken after harvest and at specific intervals during storage. Respiration rate measured at each sampling point. Fructose, glucose and sucrose were determined in potato flesh of all cultivars as ethylene has been reported to have some negative effects on non-structural carbohydrate metabolism. Sprouting was also measured at the end of the experiment. Ethylene applied after first indication of sprouting was as effective at suppressing sprouting for cv. Russet Burbank as when applied continuously; the implications of which are that the cost of ethylene application in store rooms could be reduced by manipulating timing of continuous application. In addition, application of ethylene after the first indication of sprouting had little to no effect on tuber sugar accumulation compared with continuous ethylene application from harvest.

Defensive Armor of Potato Tubers: Nonpolar Metabolite Profiling, Antioxidant Assessment, and Solid-State NMR Compositional Analysis of Suberin-Enriched Wound-Healing Tissues.

The cultivation, storage, and distribution of potato tubers are compromised by mechanical damage and suboptimal healing. To investigate wound-healing progress in cultivars with contrasting russeting patterns, metabolite profiles reported previously for polar tissue extracts were complemented by GC/MS measurements for nonpolar extracts and quantitative (13)C NMR of interfacial solid suspensions. Potential marker compounds that distinguish cultivar type and wound-healing time point included fatty acids, fatty alcohols, alkanes, glyceryl esters, α,ω-fatty diacids, and hydroxyfatty acids. The abundant long-chain fatty acids in nonpolar extracts and solids from the smooth-skinned Yukon Gold cultivar suggested extensive suberin biopolymer formation; this hypothesis was supported by high proportions of arenes, alkenes, and carbonyl groups in the solid and among the polar markers. The absence of many potential marker classes in nonpolar Atlantic extracts and interfacial solids suggested a limited extent of suberization. Modest scavenging activities of all nonpolar extracts indicate that the majority of antioxidants produced in response to wounding are polar.

Results of Еxploitation Тesting of Potato Diggers Used for Мercantile Potato Harvesting in Conditions of Northern Kosovo and Metohija

Mercantile potato harvesting is an operation that requires a quality work of potato diggers, because of the possible damage to tubers caused by the working body that can affect the quality and duration of the storage of tubers. For potatoes harvesting, the best effects are expressed by single-row and double-row diggers with a conveyor belt. This paper presents the re­sults of exploitation tests on various potato diggers used for mercantile potato harvesting in the ecological conditions of northern Kosovo and Me­tohia. The aim of our study was to determine the quality of the work of potato diggers, the power consumption and surface effect. On the basis of these results, it was concluded that the total loss of potato tubers was between 5.01% (565.7 kg ha-1) and 11.50% (1,291.2 kg ha-1) according to the yields in the studied plots. During the testing the digger generated effects ranged from 0.10 ha h-1 up to 0.28 ha h-1, with an average fuel consumption of 12.60 l hа-1 up to 19.20 l hа-1.

Chlorogenic Acid Biosynthesis Appears Linked with Suberin Production in Potato Tuber (Solanum tuberosum).

Potato (Solanum tuberosum L.) is a good source of dietary antioxidants. Chlorogenic acid (CGA) and caffeic acid (CA) are the most abundant phenolic acid antioxidants in potato and are formed by the phenylpropanoid pathway. A number of CGA biosynthetic routes that involve hydroxycinnamoyl-CoA quinate hydroxycinnamoyl transferase (HQT) and/or hydroxycinnamoyl-CoA shikimate/quinate hydroxycinnamoyl transferase (HCT) have been proposed, but little is known about their path in potato. CA production requires a caffeoyl shikimate esterase (CSE), and CA serves as a substrate of lignin precursor ferulic acid via the action of caffeic/5-hydroxyferulic acid O-methyltransferase (COMTI). CGA is precursor of caffeoyl-CoA and, via caffeoyl-CoA O-methyltransferase (CCoAOMT), of feruloyl-CoA. Feruloyl-CoA is required for lignin and suberin biosynthesis, crucial for tuber development. Here, metabolite and transcript levels of the mentioned and related enzymes, such as cinnamate 4-hydroxylase (C4H), were determined in the flesh and skin of fresh and stored tubers. Metabolite and transcript levels were higher in skin than in flesh, irrespective of storage. CGA and CA production appear to occur via p-coumaroyl-CoA, using HQT and CSE, respectively. HCT is likely involved in CGA remobilization toward suberin. The strong correlation between CGA and CA, the correspondence with C4H, HQT, CCoAOMT2, and CSE, and the negative correlation of HCT and COMTI in potato tubers suggest a major flux toward suberin.

Improving cold storage and processing traits in potato through targeted gene knockout.

Cold storage of potato tubers is commonly used to reduce sprouting and extend postharvest shelf life. However, cold temperature stimulates the accumulation of reducing sugars in potato tubers. Upon high-temperature processing, these reducing sugars react with free amino acids, resulting in brown, bitter-tasting products and elevated levels of acrylamide--a potential carcinogen. To minimize the accumulation of reducing sugars, RNA interference (RNAi) technology was used to silence the vacuolar invertase gene (VInv), which encodes a protein that breaks down sucrose to glucose and fructose. Because RNAi often results in incomplete gene silencing and requires the plant to be transgenic, here we used transcription activator-like effector nucleases (TALENs) to knockout VInv within the commercial potato variety, Ranger Russet. We isolated 18 plants containing mutations in at least one VInv allele, and five of these plants had mutations in all VInv alleles. Tubers from full VInv-knockout plants had undetectable levels of reducing sugars, and processed chips contained reduced levels of acrylamide and were lightly coloured. Furthermore, seven of the 18 modified plant lines appeared to contain no TALEN DNA insertions in the potato genome. These results provide a framework for using TALENs to quickly improve traits in commercially relevant autotetraploid potato lines.

Acrylamide in potato crisps prepared from 20 UK-grown varieties: Effects of variety and tuber storage time

Twenty varieties of field-grown potato were stored for 2months and 6months at 8°C. Mean acrylamide contents in crisps prepared from all varieties at both storage times ranged from 131μg/kg in Verdi to 5360μg/kg in Pentland Dell. In contrast to previous studies, the longer storage period did not affect acrylamide formation significantly for most varieties, the exceptions being Innovator, where acrylamide formation increased, and Saturna, where it decreased. Four of the five varieties designated as suitable for crisping produced crisps with acrylamide levels below the European Commission indicative value of 1000μg/kg (Saturna, Lady Rosetta, Lady Claire, and Verdi); the exception was Hermes. Two varieties more often used for French fries, Markies and Fontane, also produced crisps with less than 1000μg/kg acrylamide. Correlations between acrylamide, its precursors and crisp colour are described, and the implications of the results for production of potato crisps are discussed.

Participatory evaluation of Guinea yam (Dioscorea cayenensis Lam.–D. rotundata Poir. complex) landraces from Benin and agro-morphological characterization of cultivars tolerant to drought, high soil moisture and chips storage insects

Guinea yam (Dioscorea cayenensis Lam.–D. rotundata Poir. complex) is an important tuber crop that highly contributes to food security and poverty alleviation in Benin. However, its production is seriously affected by many biotic and abiotic constraints which could be overcame by concentrating the production on resistant or tolerant cultivars. In order to identify such cultivars that are known to exist in Benin traditional agriculture, 51 villages were randomly selected throughout the production zones and surveyed. Out of the 426 cultivars (subject to synonymy) evaluated using participatory approach and 13 agronomic, culinary, and technological traits, 25, 47, 49, 64 and 64 cultivars respectively tolerant to poor soils, nematodes, high soil moisture (adaptability to lowland), drought and chips (peeled and dried tuber) storage insects were, among others, identified. These pools of cultivars could serve in breeding program or be directly used in varietal exchanges towards the zones of interests. The agromorphological characterisation conducted per pool of performing cultivars revealed the existence of many duplicates that should be clarified with the use of molecular markers. Flowering, sex and intensity of flowering of the different cultivars were analysed and revealed a low rate (11.68 %) of non-floriferous plants, a high rate (61.03 %) of plants with low intensity of flowering and five types of male inflorescences indicating a hypothetical evolution towards the suppression of flowering with the cultivated yams.

Amylase and acid phosphatase activity in potato tubers treated with gibberellic acid and stored at 2°C and 8°C

Amylase activity was higher in tubers stored at 2°C and mare marked in the soaked ones (both in water and in GA<sub>3</sub>). In the late and difficult-sprouting cv. Uran, sokaing resulted in increased amylolytic activity also at 8°C stored tubers. On the contrary, the acid phosphatase activity was a little higher at 8°C than at 2°C stored tubers. At the former temperature two peaks of activity were marked:, in November–December and February–March.

Effect of Provenance and Storage Agroecology on Duration of Yam (Dioscorea rotundata Poir.) Tuber Dormancy

Crop improvement in yam is slow due to poor understanding of tuber dormancy. Tuber provenance and storage agroecology are thought to affect the duration to sprouting in yam, but systematic studies on the role of these factors are rare. The objective of this study was to determine the effects of tuber provenance and storage agroecology on the duration to sprouting in D. rotundata. Twenty landraces [comprising 7 originating from the Guinea savanna (GS), 5 from the Forest/transition (TS), and 8 from the Humid forest (HF)] were collected and multiplied at a location in their respective agroecologies: Abuja (GS), Ibadan (TS) and Onne (HF). Thereafter, 100 tubers of each of the 20 landraces were stored at each of the three sites, and dates of the appearance of shoot bud (ASB)/ sprouting were recorded. The results showed that provenance did not significantly affect the duration from planting to sprouting or the duration from date in storage to sprouting in D. rotundata. The duration to ASB varied by up to 21 days (d) for landraces originating from HF and TS, and 37 d for landraces originating from GS. Variations among landraces within a provenance group were greater than between provenance groups. This suggests that the provenance of a landrace is not a major factor controlling the duration to ASB. All landraces responded to storage agroecology/ environment in a similar manner. There was no interaction between provenance and storage environment. Tubers stored at Onne and Ibadan sprouted about 10 d earlier than those at Abuja, and this was associated with slightly higher temperature and RH at Onne and Ibadan. Storage agroecology is an important factor controlling the duration to sprouting but provenance is not.

How Potato Plants Take the Heat?

Potato is the third most important food crop in the world after rice and wheat. Because of its widely distributed cultivation and high yields, it is considered a critical species in terms of food security in face of a growing world population. However, potato is particularly vulnerable to high temperature during various stages of its life cycle. Elevated temperatures strongly suppress tuberization, negatively affect storage and shelf life of tubers and reduce fitness of seed potatoes. Breeding new heat-stress tolerant cultivars is therefore an urgent need for sustainable increases in potato production. To achieve this goal an integrated approach combining physiology, biochemistry and molecular genetics is followed to analyze the impact of elevated temperatures on source-sink relations of potato plants, potato tuber development, starch accumulation and tuber quality and tuber dormancy. First results indicate that heat effects source-sink relations by altered expression of the tuber inducing signal FT, by stimulating shade-avoidance responses of the shoot and by decreasing sink-strength of developing tubers. Sink strength of growing potato tubers is mainly regulated by the activity of sucrose synthase. Measuring sucrose synthase expression and activity of heat grown potato tubers revealed a significant down-regulation of the enzyme which is consistent with reduced tuber growth. Interestingly, genetic variation in the activity of sucrose synthase exists, potentially enabling selection of potato varieties with heat-tolerant sucrose synthase isoforms. Although FT seems to play a major role in regulating tuberization, sink-derived and additional source signals are likely to be involved in orchestrating the heat-induced shift in assimilate allocation. This assumption is based on experiments in which soil and air temperatures of pot grown potato plants were independently controlled in growth chambers and transcript as well as sugar and enzyme profiles were recorded. Results of this analysis and their implication to improve heat tolerance of potato plants will be discussed.

Fine Screening for Resistance to Cold-Induced Sweetening in Potato Hybrids ContainingSolanum raphanifoliumGermplasm

Potato is an indispensable part of human food. Many wild and cultivated potato relatives have been screened to find the best germplasm to improve productivity and quality, but only a small sample of the available biodiversity has been exploited. Most wild relatives are self-incompatible diploids. Genetic variability exists within and among populations, even within a species. Therefore, it is necessary to carry out fine screening to identify individuals carrying traits of interest. This study was carried out to quantify phenotypic variability for resistance to cold-induced sweetening, an important processing trait. Five families were evaluated for potato chip (crisp) color following cold storage of tubers harvested from four greenhouse trials and one field trial. The families were generated by crossing a single diploid clone to five plants from one accession of the wild potato relativeSolanum raphanifolium. Analysis of variance revealed that resistance against cold-induced sweetening was dependent on family and trial. This study underscores the importance of fine screening to select individuals in potato accessions for use in potato improvement.

Cultivar-Specific Variation in the Content of Nitrates (V) and (III) Depending on Potato Tuber Storage

Abstract The order to monitor the chemical pollution of food, the dynamic development of ecology and specialisation in potato production as well as its large consumption caused the investigations about the influence of storage time and genetic conditions of potato on con-tents of nitrates (V) and (III) in tubers for different use purposes during 2009–2011. In the present study, eight cultivars of potatoes with different use purposes and duration of vegetation time obtained from producer Norika Poland INC were used: ‘Albatros’, ‘Gala’, ‘Karatop’, ‘Kar-lena’, ‘Kiebitz’, ‘Lambada’, ‘Molli’ and ‘Pirol’. The tubers of cultivars used for processing such as starch pro-duction (‘Albatros’) as well as chips and crisps (‘Karlena’) were characterised by the highest content of nitrates (V) and (III). After 6 months of storage, a significant decrease of nitrates (V) and (III) contents was observed, which from the point of view of the con-sumer should be considered as the beneficial effect. Regardless of cultivar, the depletion of nitrates (V) was in the mean of 4.7% and of nitrates (III) was about 4.4%. Regardless of the use purposes, the intake of 300 g of investigated potato tubers after harvest as well as after storage time does not exceed the recommended daily allowance for nitrates (V) and (III), where after the storage time this amount is even declining.