Starch Content In Potato Tubers Research Articles

Оценка влияния органоминеральных удобрений на формирование урожая картофеля

The results of field experiments on potatoes conducted in 2023 on the experimental fields of the Agrobiotechnopark of the Kazan State Agrarian University are presented. The purpose of the research was to evaluate the impact of the use of foliar application of experimental liquid organomineral fertilizers on the formation of the yield and quality of potato tubers. The objectives of the research included studying the nature of changes in the phytosanitary condition, yield and starch content in potato tubers when using a liquid organomineral fertilizer based on humic substances and food industry waste developed at Kazan State Agrarian University. The object of research was the Red Scarlet potato variety. Biosok was used as a standard humic fertilizer. The treatment was carried out in the budding phase - the beginning of flowering with a working fluid consumption of 300 l/ha. The drugs were used individually and as part of a tank mixture. The studies were carried out on gray forest highly cultivated soil. The agroclimatic conditions of the growing season in 2023 were characterized by periodically severe drought phenomena, which negatively affected the growth and development of potato plants. It was established that treatment of potato plantings with experimental organomineral fertilizer contributed to an increase in the number of tubers and their mass formed in one bush. The largest increase (by 3.2 t/ha to the control) in potato yield was obtained when using an experimental fertilizer with a consumption rate of 0.5 l/ha. When using foliar application of organomineral fertilizer, the infection of tubers of the new crop with dry rot and common scab significantly decreased. Due to the use of experimental fertilizer, there was an increase in the marketability of tubers and an increase in the starch content in them, which is important for industrial potato growing.

The effect of increasing rates of mineral fertilizers on the yield and quality parameters of potato tubers

The yield and quality parameters of potato tubers of Gala variety were determined in the conditions of the Middle Urals in 2020 and 2022 in long-term stationary experiment after prolonged application of NPK increasing rates (30-60-90-120-150 kg a.i.). The application of NPK by 60 kg a.i./ha and more promoted the potato yield raise by 1.1-1.3 times in 2020 and by 1.3-1.5 times in 2022 compared with the control variant without fertilizers (21.4 and 14.4 t/ha by years, respectively). The lowest dry matter content over the years of research was noted at the maximum dose of N150P150K150 mineral fertilizer in the experiment– 15.6 % in favorable weather conditions of 2020 and 19.4 % in the dry 2022. The starch content in potato tubers did not depend on the dose of applied mineral fertilizers and varied in 2020 in the range from 11.1 to 13.8 %, in 2022 – from 14.4 to 16.3 %. In potato tubers the content of crude protein in the wet mass increased from 1.32 to 1.90 % in 2020 and from 1.80 to 2.65 % in 2022 to the weight of wet mass with an increase in the dose of NPK from 30 to 150 kg/ ha active substance. The sugar content in 2020 was 0.58-0.83 % for natural humidity, in 2022 – 0.23-0.47 %. The fiber content in potato tubers did not depend on the doses of applied mineral fertilizers. The application of increasing doses of NPK did not lead to exceeding the permissible value of the nitrate content in fresh potato. According to a comprehensive assessment of the quality of tubers, potato yield, obtained under given conditions, was suitable for the production of low carbohydrate potato products and for fodder purposes.

Mechanical wounds expedited starch degradation in the wound tissues of potato tubers

Starch degradation occurs rapidly in stressed plants, but it is unclear how starch degradation occurs in potato tubers after they incur mechanical wounding. In this study, we found that wounding significantly upregulated the expression levels of StGWD, StAMY, StBAM, and StISA, and decreased the starch content of potato tubers. Meanwhile, wounding markedly upregulated the expression levels of StSUS, StBG, and StINV genes, and increased the content of sucrose, glucose, and fructose. Furthermore, wounding reduced the proportion of small starch granules and increase that of large as well as medium starch granules, in this way enhancing the average size distribution of starch. Initially, the hard surface layer of starch granules was removed by wounding, but the internal channels and other structures were only slightly affected. Taken together, the results show that wounding can accelerate starch degradation by promoting the accumulation of sucrose, glucose, and fructose, and the hydrolysis of starch granules in potato tubers.

Orphan Genes in Crop Improvement: Enhancing Potato Tuber Protein without Impacting Yield.

Qua-Quine Starch (QQS), an Arabidopsis thaliana orphan gene, and its interactor, Arabidopsis Nuclear Factor Y subunit C4 (AtNF-YC4), can increase the total leaf and seed protein in different plants. Despite their potential in developing protein-rich crop varieties, their influence on the protein content of the stem, modified stem, and tuber was never investigated. Potato (Solanum tuberosum) is one of the most valuable food crops worldwide. This staple food is rich in starch, vitamins (B6, C), phenolics, flavonoids, polyamines, carotenoids, and various minerals but lacks adequate proteins necessary for a healthy human diet. Here we expressed A. thaliana QQS (AtQQS) and overexpressed S. tuberosum NF-YC4 (StNF-YC4) in potatoes to determine their influence on the composition and morphological characteristics of potato tubers. Our data demonstrated higher protein and reduced starch content in potato tubers without significantly compromising the tuber yield, shape, and numbers, when QQS was expressed or StNF-YC4 was overexpressed. Publicly available expression data, promoter region, and protein-protein interaction analyses of StNF-YC4 suggest its potential functionality in potato storage protein, metabolism, stress resistance, and defense against pests and pathogens. The overall outcomes of this study support QQS and NF-YC4's potential utilization as tools to enhance tuber protein content in plants.

Влияние норм высева и удобрений на урожайность сортов риса при различных сроках посева

The article notes that the groundnuts crop yield in mixed cropping is the result of a combination of plant growth and development, photosynthetic activity, biomass harvesting and other aspects of increasing crop performance in specific soil and climatic conditions and depends on agricultural practices. In indoor practice, it has been found that the use of mixed cropping not only increases crop performance, but also improves crop quality. The amount of oil contained in groundnuts seeds, along with fast growing tomatoes, increased by 2.7% compared to groundnuts sole cropping. When sowing groundnuts with potatoes, a slight decrease in oil content was observed (49.5%). The content of proteins in this variant decreased by 2.4–1.5% compared with groundnuts sole cropping. The quality of potato tubers, including the amount of starch, changed in mixed cropping. When mixed cropping groundnuts and potatoes, the starch content in potato tubers increased to 25%. The quality of the tomatoes has also changed. The amount of vitamin C contained in medium and early ripening tomato varieties increased to 17.3–17.9 mg/%. This is 0.6–0.9 mg/% higher than on tomato sole cropping.

The quality of potato tubers and yield by using fertilizer systems

Potatoes belong to the most important food crop, are a useful food product and a valuable raw material for food products. The quality of potato tubers depends on the fertilizer’s application and the doses of the active substance. The study about the influence of fertilizer systems (organic, organic-mineral, mineral) on the productivity and quality of potato tubers is relevant. The effect on the quality of potatoes when using fertilizer systems depends on the soil and climatic conditions of the natural cultivation zone, biological characteristics of the variety and other factors. Starch is an indicator of the quality of potato tubers. The starch content in potato tubers increases with the use of mineral fertilizers. The starch content in tubers of early-ripening potato varieties increases their marketability. During heat treatment, the size of starch grains affects the consistency of potato pulp.

Influence of insecticides on the harvest and quality of potato stubs in the conditions of West Kazakhstan region

The article presents the results on the yield of potatoes, on the starch content in the tubers, which determined a certain degree of damage to the tops of the Colorado potato beetle. The lowest yield was obtained in the control, and in the variants with the use of insecticides against the Colorado potato beetle, compared with the control, it increased in all experimental variants, depending on the chemical preparation used, in 2017 by 1.8-4.5 times, the lowest indicator by the variant with the preparation cytcor, in 2018 the yield showed a difference of 1.8-4.05 times, it was also the smallest on the variant with cytcor, in 2019 the yield increased 1.81-4.41 times and here the lowest indicator was also when using cytkor. Potato yield on average for 3 years with the use of insecticides in the fight against the Colorado potato beetle was obtained in the range of 12.6 - 16.9 t / ha in the variants of cytkor, aktara, akarin, confidor, bankol, kinmix. A high yield (25.4 t / ha) was obtained when potato plantings were treated with fastacprofi, 28.8 t / ha - in the variant using karate zeon and 29.6 t / ha when decis expert was used. The starch content in potato tubers in the control untreated variant was 10.1 - 10.3%, and in the variants with pesticides - 15.0 - 16.4%, or 4.9 - 6.1% more than in the control. Potato yield and starch content in tubers depend directly on damage to potato plants by the Colorado potato beetle.

Agroecological assessment of potato variety specimens in the conditions of the Astrakhan region

The article presents the results of the ecological test of 13 promising varieties of potato in a hot climate of the Astrakhan region. The analysis of the potato various samples productivity showed that under the spring planting period ten samples had the yielding capacity on 4.2-19.6 t/ha higher than the standard variety Impala (44.7 t/ha). High air temperatures during the summer planting period were the cause of the reduction in yield in almost all samples due to the decrease in the number and weight of tubers from one plant. The varietal specimen 10C-120-003 was able to produce a high yield under specific conditions of the region, which was on 2.4 t/ha higher compared to the same indicator in the spring planting period. The following specimens were distinguished by the starch content in potato tubers: Doka-2 and 10C-120-003 (19.2%), La Strada (18.4%), Flamingo (18.1%), Karmen (16.9%), 172/24 (16.3%), Real and 10C-135-015 (15.2%). The specimens Primabel, 802/17 and Baltic Rose have accumulated in tubers the largest amount of vitamin C, the surplus in relation to the standard was 0.1-0.3-0.6 mg% respectively. The cost-effectiveness analysis showed that cultivation of potato in the conditions of the Astrakhan region on drip irrigation conditions is profitable.

Experience in the use of BoHum humic preparation in the cultivation of vegetable crops

Humic preparations are becoming more and more popular. At the All-Russian Research Institute of Reclaimed Lands - a branch of the Federal Research Center "Soil Institute named after V.V. Dokuchaev" a method for obtaining humic preparation BoHum, which contains at least 10 g / l of humic acids, the presence of macro- and microelements, pH not more than 9.0 was developed. The humic preparation BoHum was used for foliar feeding of carrot plants grown on low-lying peat soil and for processing potato tubers before planting in sod-podzolic soil. The use of BoHum as a foliar feeding influenced carrot plants through the leaf surface and through the soil during the first and partially second spraying. As a result, the working solution BoHum 1: 300 contributed to obtaining the maximum increase in the yield of carrots - 13.4% (the relationship between the yield and the coefficient of mineralization in peat soil r= 0.90). Treatment of potato tubers with the humic preparation BoHum led to more intensive plant development (plant height increased by 23% on average) and activation of soil microflora, which affected the potato yield (r= 0.88). The maximum yield was obtained in the variant of using the BoHum working solution 1:10 - 10.3%. As a result of the use of BoHum, the quality of vegetable products improved: carotene in carrot roots increased by 15%, the starch content in potato tubers averaged 13.5% versus 12.6% in the control, the nitrate content was almost two times lower than the MPC for these crops.

QTLs for potato tuber resistance to Dickeya solani are located on chromosomes II and IV

AbstractThe goal of this research was to identify quantitative trait loci (QTLs) for potato tuber resistance to the soil‐ and seedborne bacterium Dickeya solani and for tuber starch content, to study the relationship between these traits. A resistant diploid hybrid of potato, DG 00‐270, was crossed with a susceptible hybrid, DG 08‐305, to generate the F1 mapping population. Tubers that were wound‐inoculated with bacteria were evaluated for disease severity, expressed as the mean weight of rotted tubers, and disease incidence, measured as the proportion of rotten tubers. Diversity array technology (DArTseq) was used for genetic map construction and QTL analysis. The most prominent QTLs for disease severity and incidence were identified in overlapping regions on potato chromosome IV and explained 22.4% and 22.9% of the phenotypic variance, respectively. The second QTL for disease severity was mapped to chromosome II and explained 16.5% of the variance. QTLs for starch content were detected on chromosomes III, V, VI, VII, VIII, IX, XI, and XII in regions different from the QTLs for soft rot resistance. Two strong and reproducible QTLs for resistance to D. solani on potato chromosomes IV and II might be useful for further study of candidate genes and marker development in potato breeding programmes. The relationship between tuber resistance to bacteria and the starch content in potato tubers was not confirmed by QTL mapping, which makes the selection of genotypes highly resistant to soft rot with a desirable starch content feasible.

Assessment of breeding hybrid potatoes in irrigated conditions of the steppe zone of the Southern Urals

The creation of varieties with a high potential productivity and adaptability applied to the environmental conditions of a particular climatic zone is the main goal for breeding programs. The purpose of this work is studying and identifying the most adaptable hybrid materials that are most adaptable to the conditions of the steppe zone of the Southern Urals for selection, combining high productivity, resistance to major diseases with the complex of economically valuable traits. The objects of research were breeding hybrids 10.76.32; 02.40.17; 01.2.50; 01.12.51; M07.48.19; 05.57.32 and 10.02.19 obtained in the potato breeding laboratory of the South Ural Scientific Research Institute of Horticulture and Potato. Assessment of the represented volume of samples was carried out according to the morphological characteristics of plants, productivity, marketability, starch content in potato tubers, culinary type, taste, resistance to pathogens (Erwinia carotovora atroseptica, Clavibacter michiganensis sepedonicus, Dickey pectobacterium atrosepticum, Phytophthora infestans, Streptomyces scabies, PVM, PVS, PVX, and PVY). The breeding hybrids under study significantly exceeded the variety - standard Nevsky - in terms of yield by 97-1182g per bush. The highest starch content was recorded in breeding hybrids: 02.40.17 (18.4%), M07.48.19 (18.2%), 0.1.2.50 (17.6%). In taste the highest tasting score received - M07.48.19, 02.40.17 (5 points), 05.57.32 (4.5 points), 10.02.19 (4.7 points). The culinary type assessment showed that to the salad type (preferably not fall apart) applies the selection hybrid 10.76.32. Over the years of research low susceptibility to the pathogens under consideration was possessed by the following hybrids: 01.12.51, M07.48.19 and 05.57.32.

Cultivation of potato varieties adapted to the soil and climate conditions of the Euro-North-East

Relevance and methods . During 2014–2019, a comparative test of three varieties (Zyryanets, Vychegodsky, Pechorsky) and one hybrid (1603-7) of potatoes was conducted in the Komi Republic. Results. As a result of research, it was found that on average for 6 years, the highest yield of tubers was obtained from the variety and amounted to 36.0 t/he and exceeded the standard varieties: Nevsky by 15% and Udacha by 36.8%. In terms of starch content in potato tubers, the «Zyryanets» variety was the leader — 16.0%, the «Vychegodsky» variety — 15.7%, and the Pechorsky variety — 14.1%. In standard varieties the amount of starch was Nevsky by 14.6% and Udacha by 14.8%. The highest amount of vitamin C was in the «Pechorsky» variety — 14.0% for other varieties — 11.4–15.4%. The dry matter content in tubers of various varieties varied from 20.9 to 23.9%. The largest collection of starch per hectare was obtained in the Pechorsky variety (5.01 t/he), Zyryanets (4.94 t/he), and in standard varieties 3.89–4.57 t/he.

EQTL mapping of the 12S globulin cruciferin gene PGCRURSE5 as a novel candidate associated with starch content in potato tubers

Tuber starch content (TSC) is a very important trait in potato (Solanum tuberosum L.). This study is the first to use expression quantitative trait loci (eQTL) mapping of transcript-derived markers for TSC in potato. Thirty-four differentially expressed genes were selected by comparing the RNA-seq data of contrasting bulked segregants. For the 11 candidate genes, we determined their relative expression levels across the segregating diploid potato population using RT-qPCR. We detected 36 eQTL as candidate genes distributed on all twelve potato chromosomes, and nine of them overlapped with QTL for TSC. Peaks for two eQTL, eAGPaseS-a and ePGRCRURSE5, were close to the corresponding loci of the large subunit of ADP-glucose pyrophosphorylase (AGPaseS-a) and the 12S globulin cruciferin gene (PGCRURSE5), respectively. The eQTL peaks for AGPaseS-a and PGRCRURSE5 explained 41.0 and 28.3% of the phenotypic variation at the transcript level. We showed the association of the DNA markers for AGPaseS-a and PGRCRURSE5 with QTL for TSC, and significant correlation between the expression level of PGRCRURSE5 and TSC. We did not observe a significant correlation between the expression level of AGPaseS-a and TSC. We concluded that the cruciferin gene PGRCRURSE5 is a novel candidate involved in the regulation of starch content in potato tubers.

ДЕЙСТВИЕ МИКРОУДОБРЕНИЯ «АГРО-МАСТЕР» НА УРОЖАЙНОСТЬ И КАЧЕСТВО КЛУБНЕЙ КАРТОФЕЛЯ

The effect of microfertilizer «Agro-Master» on the yield and quality of early and medium early of potato tubers varieties was studied, carried out at the experimental field of North Caucasus Research Institute of Mountain and Foothill Agriculture - branch of the VSC of RAS in the forest-steppe zone of Republic of North Ossetia-Alania on grass rotation in the period from 2017 to 2019 yy. The experimental data indicate that the use of microfertilizer «Agro-Master» in a specific soil and climate zone is a promising technique that can improve the productivity and quality of potato tubers in the field. The data of our studies on leached chernozems showed no clear differences in the timing of the onset of the development phases of potatoes. The intensity and speed of emergence of seedlings to a greater extent depends on weather conditions and varietal characteristics. It was found that when spraying potatoes with microfertilizer «Agro-Master» in different doses, the process of dying of tops is slowed down in comparison with the control options. So, in the Zukofsky early variety, the top-off phase begins 7-8 days earlier than the Red Scarlett variety and 10-11 days of the Predgorny variety of local selection. The maximum yield increase was observed when processing of the microfertilizer «Agro-Master» at a dose of 2 kg/he on the pre-mountain local breeding grade – 27,5 tons per hectare, while the increase in yield to control was 5,0 tons per hectare, for varieties of Zukofsky early and Red Scarlett – 5,0 and 4,7 tons per hectare respectively. The highest dry matter content was on the experimental version (dose 2 kg / ha) for the Predgorny variety – 26,6 %, the Zukofsky early and Red Scarlett varieties – 25,9 and 23,8 %, that accordingly is more than control on 3; 2 and 3 %. The starch content in the studied potato tubers in the experimental varieties was diverse. The maximum starch content in potato tubers was obtained using the variant treated with Agro-Master at a dose of 2 kg/he for Predgorny variety (16,0 %), which is explained by the favorable influence of microfertilizer «Agro-Master» and the manifestation of varietal characteristics.

CHANGE OF MAINTENANCE OF DRY SUBSTANCES AND STARCH IN TUBERS OF POTATO IN DEPENDENCE ON TERMS OF TILL

Potatoes is the most important food crop, one of the main crops grown throughout the world. A way to improve the profitability of the potato industry is processing. The processing production requires special varieties of potatoes. Tests were carried out by the department of vegetable breeding «Agrarian scientific center of republic of Dagestan» in 2017-2018 with the purpose of study the effect of soil-climatic conditions of Dagestan highlands on dry matter and starch content in potato tubers for production of processed potato products. Processing of potatoes is one of the methods to increase profitability of industry. One of the quality indexes of the use of potato varieties for their processing is high level of dry matter and starch. As a result of the research, the following varieties were identified: high-yielding are Impala, Irbit, Zhukovsky Ranniy, Manifesto, Matushka, Nevsky, Primabella, Rosara, Silvana, Spiridon and Udacha; high dry matter content are Alena, Vektor, Dzhokonda, Desiree, Matushka, Nart, Primabella and Rossi; high in starch: Desiree - 23%, Vector and Primabella - 22.2% each. The results of the present investigation revealed that climate of the mountainous areas of Dagestan republic promotes the increase of dry matter and starch content in potato tubers by 3-4%.

Potato Tuber Yield and Quality Under Different Potassium Application Rates and Forms in West Siberia

Abstract Potato cultivars have different strategies for dealing with potassium (K) deficiency in soil, and their response to different forms and rates of K fertilisation may vary because of differences in soil K availability. This study was performed to evaluate the effect of K fertilisation rates (0, 30, 60, 90, 120 and 150 kg K/ha) on tuber yield and quality (dry matter, starch, sugar and ascorbic acid content, taste) of two potato cultivars (Roco and Rosara) grown in the microplot field experiment on Luvisol in the forest-steppe zone in southern West Siberia, Russia (NL 54.422106, EL 83.160257). The tuber yield of both potato cultivars increased with increase in K application rate up to 2.1 and 2.9 kg/m2 for Roco and Rosara, respectively. Sugar content, averaging 3.5%, was mostly determined by cultivar; however, in both cultivars it tended to decrease with increasing K application rate. The application of K fertiliser in the form of sulphate as compared to chloride increased dry matter content from 22.4 to 23.8% and ascorbic acid content from 13.2 to 14.6 mg/100 g fresh mass. Starch content of potato tubers averaged 59.7 ± 4.8% over all K fertilisation variants, with cultivar responses being different. Potassium application rate did not affect Roco tubers’ taste, while improving Rosara tubers’ taste under moderate application rates. The results underscore the importance to adjust fertiliser recommendations concerning potassium application rates and source on the basis of biological requirements and intended utilization of individual potato cultivars

КАЧЕСТВО УРОЖАЯ СЕЛЬСКОХОЗЯЙСТВЕННЫХ КУЛЬТУР НА ЕВРОПЕЙСКОЙ ТЕРРИТОРИИ РФ В УСЛОВИЯХ ИЗМЕНЕНИЯ КЛИМАТА

The positive trend of starch content in potato tubers under the conditions of Murmansk Province and sugar content in grapes under the conditions of Rostov Province is shown for the period of the 1990s. Weather dependence of protein content in wheat was investigated in the experiments of 1963-1993 at four experimental stations of the Vavilov Institute. Direct dependence of the studied quality indicators on the sum of temperatures above 15°C and inverse dependence on the sum of rainfall for this period have been identified.

Study on Correlation between the Starch Content of Potato Tuber and its Viscoelastic Characteristics

When potato tubers had received the exogenic action, water and starch in tubers generated tougor pressure which would act on cell walls in the tuber tissue, so starch content and water ratio have an obvious effect on the mechanical characteristics of potato tubers. In order to provide a mechanical method for detecting the starch content of potato tubers, correlation between viscoelastic characteristics and starch content of tubers was studied. In the research, the tubers of Desiree potato were compressed by cylindrical probe, and showed nonlinear stress-strain curves. The viscoelastic model of potato tuber was established, and its viscoelastic parameters were determined. Meanwhlie, the starch content and water ratio of potato tuber were detected after mechanical tests, and the correlation between viscoelastic parameters and starch content was analysed. According to the results of correlation analysis, viscosity coefficient which had been obtained from the viscoelastic model was significantly correlated with starch content and water ratio. Finally, the regression equation of starch content and the viscosity coefficient was determined.

Effect of nitrogen application on selected nutritional components of potato tubers

In this work the influence of graduated nitrogene fertilizers doses to the soil on starch and vitamin C formation in potato tubers grown in field conditions in locality Veľká Čalomija was studied. The investigated potato cultivar Solara is medium early potato cultivar. The determined average starch content in potato samples ranged in interval 12,426 % - 15,084 %, while the highest starch content was determined in variant 1 (without nitrogen addition to the soil). The starch content in potato tubers was decreased in order: variant 1 (15,084 %) > variant 2 (14,427 %) > variant 3 (14,378 %) > variant 4 (14,023 %) > variant 5 (12,603 %) > variant 6 (12,426 %). The content of C vitamin was increased with the graduated nitrogen doses to the soil only till variant 4 and after that the content of vitamin C was decreased. The average content of C vitamin ranged in interval 3,786 - 6,225 mg.kg-1 of fresh matter.

Soil nitrogen variability in relation to seasonal nitrogen cycling and accumulation of nitrogenous components in starch processing potatoes

Seasonal dynamics of total soil nitrogen, ammonium and nitrate ions contents were evaluated for a processing potato field experiment conducted on three sites with different altitudes. Fertilization levels of 100 and 200 kg N ha−1 applied before potato crop planting were compared. Content of soil ammonium and nitrate ions ranged from 1.5 to 149 mg kg−1 and from 3.0 to 108 mg kg−1 on soil dry matter basis, respectively and showed strong seasonal dynamics with a rapid increase of the content during June and subsequent fall down to initial values. The nitrogen fertilization level had minimal effect on seasonal dynamic of total soil nitrogen, ammonium and nitrate ions contents. The higher fertilization level significantly increased crude protein content in potato tubers and yield of crude protein per area unit. The factors of starch content in potato tubers and yield per area unit were affected negatively by the higher dose of nitrogen fertilization. It could be concluded that the dose of 100 kg N ha−1 is sufficient for production of potato tubers with high content of both crude protein and starch, especially in production areas with higher altitude. The dose of 200 N is justifiable only in production areas with lower altitude (below 400 m a.s.l.) that are not so suitable for accumulation of crude protein and starch in potato tubers.