JWSS - Journal of Water and Soil Science

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Potato is a valuable plant as a source of nutrition and as an industrial product. The modification and breeding of potato plants are very difficult, or even impossible, via the conventional plant breeding programs. However, plant biotechnology and tissue culture are reliable methods which can produce plant material for gene transformation using Agrobacterium as a vector. In this study, one-, two-, and three-step methods of plant regeneration from stem culture of potato cv. Delaware were tested. Among these only the one-step procedure using TDZ, a synthetic cytokinin, was the best for rapid plant regeneration. In this culture medium, several shoot buds and shoots were regenerated from stem culture, while the other methods using a culture medium supplemented with BAP, NAA, zeatin, 2ip, IAA produced white and green callus. Morphology and chromosome number of all regenerated plants were similar to the original plants. The results showed that the regeneration system was suitable for cv. Delaware and that the culture conditions prevented genetic variation of the regenerated plants.

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Physicochemical characteristics of potato (Solanum tuberosum L.) are very important for storage and processing qualities. The amount of reducing sugars (glucose and fructose) and organic acids at harvest, during and after storage is the most important factor. In this study, three potato cultivars (Moran, Marfona and Agria) were collected, dry cleaned and graded into three sizes. They were analyzed for specific gravity and dry matter content. Potato tubers were stored at 4°C and about 85% R. H. for 15 weeks and then reconditioned at room temperature (25±l)°C for 4 weeks. During the storage period of tubers, sugars (sucrose, glucose and fructose) were analyzed on a weekly basis, but citric, D-malic and D-pyroglutamic were analyzed on a monthly basis by high performance liquid chromatography (HPLC). Data were analyzed statistically in a completely randomized design with sampling and Duncans multiple range test.

The total sugar and organic acid contents of tubers significantly increased during the 15 weeks of storage at 4°C and decreased after reconditioning at room temperature. The size of tubers did not affect the accumulation of total sugars. Dry matter content and specific gravity of Agria tubers were higher than those of both Moran and Marfona. Also accumulation of reducing sugars was lower in Agria than in Moran and Morfona initially and after the storage and reconditioning periods. Therefore, Agria must be suitable for processing into chips or dry powder.

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Any mechanical force exerted on a potato tuber during the harvesting may result in mechanical damage. A few weeks prior to harvesting, haulm destruction could improve the rheological properties of the tuber and reduce its susceptibility to mechanical damage. The effects of elevator and oscillatory sieve diggers and haulm destruction on potato loss and mechanical damage were studied on a farmer field in Fereidan region of Isfahan. Two haulm management treatments (destruction and non-destruction) along with five potato diggers (elevator digger with a long main web and with agitator, elevator digger with primary and secondary webs and with agitator, elevator digger with a main web and with/without agitator, and reciprocating riddle digger) were laid out in a strip block design within a randomized complete block design with four replications. The main crop variety, namely Marfona, was planted in the field.

The results showed that the percentages of undigged and soil-covered tubers were significantly different among the potato diggers tested. These losses were due to the dices located to the sides of shares or gage wheels and wrong adjustments on the diggers. Comparing the performance of reciprocating riddle with elevator diggers, its sieving capacity was low and the severity of the mechanical damage and the numbers of tubers covered with soil were high. Haulm destruction was effective in reducing the peeler type damage (the less than 3 mm deep damage to flesh). Although the elevator digger with a main web (elevator chain) and without agitator had the least mechanical damage index, the differences among the elevator diggers tested were not significant (5%).

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Three potato cultivars (Solanum tuberosum L.), spring Marfona, autumn Cosima and Marfona, obtained from Isfahan Province, were stored under different conditions: 4^oC, darkness 12^oC, fluorescent light room temperature, darkness and room temperature, daylight. Relative humidity of the above stores was 85 to 90%. Analyses were carried out to determine total glycoalkaloids, α-solanine, specific gravity and total solids, during 30 days for the spring cultivar and 90 days for the autumn cultivars in stored tubers. α -Solanine content of each cultivar was determined by HPLC, in mg per 100 g dry weight, at the beginning, the midinterval, and the end of storage periods. Also, amounts of α-solanine in autumn cultivars, which showed the highest levels after storage for sixty days, were determined before and after heat processing for frying and cooking. Data were analyzed statistically by completely randomized design with Duncan’s multiple range test. The results revealed that the amount of α-solanine of the spring cultivar considerably increased under 12^oC and flourescent light as compared with the other storage conditions. The amounts of α-solanine considerably increased during the storage of autumn cultivars which were stored at 12^oC under flourescent light compared with those stored at room temperature and daylight, room temperature and darkness, and at 4^oC and darkness, respectively. The amount of α-solanine decreased due to spring conditions during the storage period for cultivars stored at room temperature and darkness. In spite of the decreasing effect of peeling, before frying and after cooking, frying and cooking processes had no effect on the amount of α-solanine in the samples. Therefore, according to the above results, the most appropriate storage conditions to prevent increasing effect of α-solanine in potato tubers was 4^oC in darkness.

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The commercial potato is an autotetraploid species. Certain allotetraploid species such as S. acaule despite theire identical ploidy level are not crossable with commercial potato due to their different endosperm balance numbers. The aim of this experiment was to investigate the possibility of germplasm transferring from allotetraploid species to cultivated potato by the use of diploid species and 2n gametes. For this purpose, one clone of S. phureja was crossed with S.acaule. The resulting F₁ seeds were planted the next year. For evaluation of male fertility and unreduced gametes, the pollen samples of F₁ hybrids stained with acetocarmin glycerol were assessed. For chromosome counting the tips of stolons were fixed and after staining with aceto – iron- hematoxilin were squashed. For future crossing some hybrids were grafted on tomato stocks. Cytologycal observation revealed that hybrids were triplod. Male fertility of hybrids as expected for odd ploidy was low, but approximately all of them had a few large stainable pollen (putative 2n). crossing of the hybrids as male parent with S. tuberosum was not  successful, but reciprocal cross was successful and 72 seeds were obtained from 380 pollination . considering EBN, it is exected that the resulting seeds originate from fertilization of unreduced gametes of triploid and n gamates of S. tuberosum to be pentaploid or near pentaploid. The applications of these hybrid in potato breeding via ploidy manipulation have been discussed. 

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The black dot disease of potato is a fungal disease caused by Colletotrichum coccodes (syn. C. atramentarium) that produces accervuli on infected underground plant parts which appear as black dots. The disease appears at the flowering stage and develops up to the season end. The survey on black dot disease of potato in two successive years indicated that the infection percentage is 39.86 in Feraydan (Isfahan), one of the most important potato production regions in Iran. Studies on usual cropping patterns with, potato including, wheat alfa-alfa, barley and fallow showed that in terms of disease infection, one year rotation with fallow reduced the disease severity almost to half compared with control and other cropping patterns. Biological seed and soil treatment, with Trichoderma harzianum in various spores density reduced the disease in various degrees significantly and increased the potato plant growth factors including the number of stems, foliage fresh and dry weights, and also the yields in cases of spore applications, depending upon the type and application dosage. Comparative susceptibility assessments of 24 commercial potato varieties to the black dot disease indicated that the variety Desiree was the least concerned in terms of infection, followed by Scort ,Casser, Casmos, Carlita and Moren , where as Marijke, Cosima and Monalisa were highly infected in comparison to other tested verities and the rests of varieties were scored within these two ranges.

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Representatives of fluorescent pseudomonad strains were assessed for their antagonistic activity against the blackleg of potato pathogen, Pectobacterium carotovorum subsp. atrosepticum. Tested strains belonged mainly to Pseudomonas fluorescens Biovars III, IV and V and they could produce inhibition zone on PDA medium against P. c. subsp. atrosepticum ranging from 1.5-5.5cm. Six selected strains were used in two concentrations 10⁷-10⁹ and 10¹⁰-10¹² colony forming units to control potato blackleg disease caused by P. c. subsp. atrosepticum under greenhouse conditions. Results showed that all strains applied could reduce the disease ranging from 46 to 71 percent. There was no significant difference among strains and their two concentrations under greenhouse conditions. Most of the strains applied increased potato fresh weight and all of them produced antibiotic and siderophore compounds in vitro.

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Potato (Solanum tuberosum L.) has relatively weak root system and requires high nitrogen fertilizer which is costly and may pose environmental pollution. This study was conducted to compare root morphological characteristics and nitrogen uptake of some potato cultivars growing in Iran. A greenhouse experiment using a completely randomized design with 3 replications and 8 potato cultivars including: Arinda, Agria, Premiere, Diamant, Concord, Marfona, Marodana and Nevita was conducted at Isfahan University of Technology, Isfahan. Virus-free seed tubers were planted and grown up to flowering stage. The plants were then harvested and their root length (RL), root average diameter (RAD) and root surface area (RSA) were determined using a Delta-T Scan image analysis system and Windias software. Root length density (RLD), root length and shoot weight ratio (R/S) were also calculated. Dry mater production and nitrogen accumulation (total nitrogen uptake) (PNA) were also determined. Soil inorganic nitrogen was measured before planting and after harvest. All measured parameters, except RAD, were significantly (p<0.05) affected by cultivar. Large differences observed between cultivars for all traits indicated genetic diversity among the studied potato cultivars. The highest and the lowest values of RL, RLD, RSA, R/S, RDW and PNA were found in Marfona and Nevita respectively. Based on cluster analysis, cultivars were divided into four different groups. Under the condition of this study, Marfona was superior whereas Arinda, Nevita, Marodana and Agria were inferior. Due to the high differences in root morphological characteristics and nitrogen uptake among potato cultivars, plant breeders may produce cultivars with larger root volumes and high nitrogen uptake.

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For production of fabricated potato chips, two potato- cultivars namely, Agria and Marfona, were obtained from Daran region of Isfahan Province and stored in cool storage at a proper and constant conditions ( T = 9°C and RH=85% ) . Specific gravity, dry matter and reducing sugars were determined at the time. Potato granule was prepared from both the cultivars by the Add-back procedure. To prepare a sheetable dough, potato granule, corn flour, emulsifier, shortening, water, starch, salt and wheat flour were used. After formulation of a non- adhesive dough, it was sheeted to thickness of mm and formed into slices of 3 cm diameter. These slices were processed by baking, vacuum drying, deep frying and combination of pre-drying and deep frying methods. To select the sample with the best texture a multiple comparison taste panel was held .The best method was baking at 125 for 30 minutes. To improve flavor and acceptability of selected chips, different seasonings (garlic powder, pepper, thyme, lactic acid, onion powder, salt, sugar) were used in chips formula and were compared by multiple comparison and triangle tests. Panelists selected treatments containing salt, pepper and garlic powder as the best formulatins.

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Evaluating different aspects of government policy in terms of their indirect and welfare effects has been always of interest. In this study, the effects of gauranteed purchasing policy on land under cultivation and yields of cotton, potatoes and onions were investigated in Fars province. For this purpose, a Nerlove model was applied to time series data of 1972-02 after testing their stationary to estimate the cultivated lands and yields functions of these products. The use of protection rates as explantory varrables is one of the interesting characteristic of such a model. Although the results were not similar for all the products, the indication is that the policy has not had significant influence on the land areas and yields of cotton, potatoes and onions. However, taking into account that the policy has been recentely commenced in Fars, and that the policy takes time to become effective, the policy may result in different outcomes in the long run.

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The identification of potato cultivars is a recurrent objective of potato research. The research is prompted by the increasing number of potato cultivars and the importance of seed purity. In developing a reliable method for identification of the imported potato cultivars and determining their genetic relationship, the capacity of 10 polymorphic simple sequence repeat markers (SSRs) was evaluated for the analysis of 28 commercial cultivars of potato. The number of alleles detected at different loci ranged from 3 to 10 alleles with a total of 57 for all loci and a mean of 5.7 alleles per locus. In the 28 potato cultivars analyzed, the number of heterozygous genotypes per locus varied between 6 to 28 with an average number of heterozygous genotypes per locus of 18, considering the 10 loci studied. Based on the resulting dendrogram of jacquard's similarity coefficient and UPGMA analysis, the potato cultivars were placed in two major groups. However, the results from similarity coefficient confirmed the close phylogenetic relationships among members in each cluster. The dendrogram derived from SSRs data clustered together Kenebek, Florida and Atlantic which are known as American potato cultivars, but Stanbuli, an old cultivar in Iran, was placed in concert with European cultivars. This finding might be an indication that this cultivar along with other unidentified cultivars, growing in local fields, has been introduced from European countries to Iran. The results obtained illustrate the appropriate utility of SSRs to assess genetic relationships of potato cultivars and develop a PCR- based tool for evaluation of potato seed purity.

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To determine the preheating effect on frozen French - fries quality, four potato cultivars: Agria, Marfona, Auozonia & Auola were selected from Faridan region in Isfahan province & transferred to cold storage at temp.=5+0.5°C and RH=85-90%. At first, some physico – chemical characteristics of potato tubers such as specific gravity and dry matter content were measured by A.O.A.C methods. Also reducing sugar contents were analyzed by “High Performance Liquid Chromatography” (HPLC). The potato strips were blanched in hot water at different condition: 70°C - 4 min, 70 °C 10 min, 95 °C - 2min and then deep - fat fried at temperature 175°C for 2 minutes. Product quality properties such as texture, color and oil absorption were determined by standard methods. The data were analyzed using a factorial experiment in a completely randomized design, and average comparisons were made by by Duncan's multiple range test (p < 0.01). The results showed that blanching at 70 °C for 10 minutes markedly improved the quality parameters. Treatment at 95 °C – 2 min did not have any significant effect on Hunter Lab color parameters compared with 70 °C – 10 min. treatment, but the texture was significantly different. The oil absorption increased in strips blanched at 95 °C for 2 minutes. The samples blanched at 70 °C – 4 min had no significant effect on the product quality. In conculsion, Agria &Auola cultivars were more suitable for manufacturing French - fries than the other two varieties.

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Potatoes are the third most important food crop in Iran. But fluctuations in the production of potato have made imbalances in supply and demand. Lack of appropriate planning for cultivation and marketing operation and farmers’ little knowledge of marketing provides a ground for uncertainty about marketing. To compete successfully in markets, knowledge on marketing is necessary. Succeeding in markets is possible by conducting the marketing educational programs. The broad objective of most marketing educational programs is to help producers modify production and marketing. The first stage in planning of marketing programs is to determine the educational needs. Therefore, needs assessment before planning and conducting to programs is necessary. In this study the educational needs of potato farmers regarding marketing have been considered. The descriptive- correlational research methodology was used in this study. The target population included potato farmers from Ajabshir Township, East Azerbaijan Province. A random sample of 110 potato farmers was selected by multistage cluster random sampling method for completing the questionnaires. Research results indicated that respondents’ technical knowledge in marketing is low especially in pricing and marketing. The most important educational needs of respondents were marketing and pre-harvest activities. The independent variables such as age, literacy rate, yield rate, experience of potato farming and size of potato farms did not have any significant relationship with educational needs. Based on respondents’ opinions, the best educational method was meeting agents on farm and conducting the educational courses.

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During summer of 2004, tuber and stem samples of potato plants showing wilt symptoms were sampled from different fields of East Azarbaijan, Fars and Karaj provinces. A total of 39 bacterial strians were isolated and based on the morphological, biochemical characters and pathogenicity tests were divided in to two district group. All the strains of East Azarbijan and Karaj provinces were identifeid as race 3 / biovar 2A of Ralstonia solanacearum and strians of Fars province were identified as race 3 / biovar N2 of the bacterium. Distinct differences were observed in utilization of carbon (D-trehalose, D-ribose and tartrate) as well as tyrosinase activity and protein profiling in SDS-PAGE among the two biovars. Based on the results of phenotypic tests, eight strians of biovar 2A were selected and their plasmids were extracted and electrophoresis on 0.7% agarose gel. All the strians had a single plasmid with similar size and no variation was observed among the strains. According to available literature, this is the first report of occurrence of biovar N2 of R. solanacearum in Iran.

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Factor and principal component analyses are widely used in different sciences especially in agricultural science. To determine the factors that create variation between potato cultivars, in normal (non-stress) and water deficit (stress) conditions, two experiments were conducted in the form of randomized complete block design with three replications in summer 2002. Stepwise regression analysis showed that in normal conditions, stem length, number of stems/plant and leaflet width contributed significantly to yield. In stress condition, other than stem length and number of leaves/main stem, leaflet length also entered the model. As is evident, stem length had a detrimental effect on tuber yield in both stress and non-stress conditions. So, this trait could be used as an important criterion for the selection of high yielding genotypes. Principal component analysis revealed that number of stem, leaf length and leaf width were important traits creating variability between potato cultivars, especially number of stem that had high coefficients in the first principal for both environments. Factor analysis distinguished two factors in normal environment named leaf surface and structural attitude factors, and also two factors in stress environment called photosynthetic surface and structural attitude. Therefore, these factors should be intervened and attended to in breeding programs.

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In order to determine the potato cultivars responses to irrigation regimes and fertilizer combinations, an experiment was conducted on Fereidan Research Farm, Isfahan Province in 2003. The trial was designed as split-split plot based on randomized complete block design with three replications. The cultivars (Arinda and Navita) were planted as main plots, and irrigated after 70, 140, 210 mm water evaporation from standard A pan surface that provided optimal watering, mild drought, and severe drought, respectively, as sub plots. Fertilizer combinations including of NPK + Zn, NPK+ Mn, NPK +Zn + Mn and NPK+ Manure were used as sub-sub plots. Results showed that the cultivar Arinda produced higher yield, mean tuber weight and total tuber number. By decreasing the amount of irrigation, the total yield and mean tuber weight were decreased. The highest amount of seed tubers (35-55 mm diameter) and marketable tuber sizes (diameter>35mm) and lowest amount of small size tuber numbers (diameter <35) were obtained in moderate drought. The use of NPK + Zn + Mn and NPK+ Manure produced the highest yield and mean tuber weight. Planting the cultivar Arinda with efficient irrigation is suggested in Isfahan province. Moderate drought is recommended for production of higher amount of seedy tubers. A combination of manure, Mn and Zn fertilizers are also suggested for potato farms of this district.

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Potato is one of the most important tuberous crops. To achieve optimum yield in potato, suitable brand and sufficient and balanced soil nutrients are necessary. In order to study the effects of Zinc, Manganese and Copper on potato yield and leaf and tuber concentrations of Phosphorus and Iron, a factorial pot experiment with 32 treatments was conducted in greenhouse of Soil Science Department, Zanjan University, using a completely randomized design and three replications. The study factors were four levels of Zinc(Zn0: 1.14, Zn1: 5, Zn2: 10 and Zn3: 15 mg/kg soil), four levels of Manganese(Mn0: 1.4, Mn1: 5, Mn3: 10 and Mn4: 20 mg/kg soil) and two levels of Copper (Cu0: 0.22 and Cu1: 2 mg/kg soil) which were applied to the soils of planting pots. The results showed that potato yield increased as the soil concentrations of Zinc, Manganese and copper increased to certain levels Soil application of zinc and manganese fertilizers significantly decreased leaf and tuber concentrations of Phosphorus and Iron. Soil application of copper decreased Iron concentration of leaf but not Phosphorus. The highest potato yield was obtained from the treatment of 15, 10 and 2 mg zinc, manganese and copper per kg of soil, respectively.

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In this study, a completely randomized experiment was designed with five irrigation treatments and three replicates. The irrigation programs were raw wastewater (T1), treated wastewater (T2), a combination of 50% raw wastewater and 50% fresh water (T3), a combination of 50% treated wastewater and 50% fresh water (T4), and fresh water (T5). The experiments were run within a greenhouse. The lysimeters were built up in September 2009 and they were filled with a two layer soil. The upper (30 cm) and lower (40 cm) layers were sandy loam and sandy clay loam, respectively. The results showed that the effects of watering treatments on transfer coefficients of heavy metals from soil to shoots (except Cd) and tubers of potato (except Zn and Cu) were significant (p <0.01). Maximum and minimum transfer coefficients of heavy metals were observed in the (T1) and (T5) treatments, respectively. Also, the transfer coefficients of Cd from soil to shoots were lower than tubers. In the case of Zn, Cu and Pb, transfer coefficients from soil to tubers were lower than shoots. In this study, the maximum transfer coefficients to shoots were Cd (0.331-0.463), Zn (0.383-0.230), Cu (0.173-0.386) and Pb (0.003-0.057), respectively. Maximum transfer coefficients toward tubers (except T5) were Cd (0.439-0.572), Cu (0.081-0.138), Zn (0.170-0.217) and Pb (0-0.017), respectively. The combination of wastewater and fresh water use in short-term irrigation might be feasible, but a heavy metal monitoring program is necessary.

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efficiency was investigated during a 2-year period (2009-2010) in a silty clay loam soil in Tajarak Research Station (Kaboudarahang Township), Hamedan. The experimental design was a strip-plot within a randomized complete blocks design. The horizontal band, the irrigation water rate after flowering, included full and deficit irrigation (100% and 75% potato water requirement) and the vertical band, kind of inter-planting row tillage including 1- subsoiling to 30-35 cm soil depth, 2- chiseling to 20-25 cm soil depth, 3- sweeping to 5 cm soil depth and 4- no-till. During the growing season, soil mechanical resistance (cone index) in two stages and water infiltration into the soil were measured. At the end of the growth season (harvesting time), potato yield quantity and quality were measured. Result showed that the effect of inter-row tillage on soil mechanical resistance was significant. Subsoiling and chiseling had lower soil mechanical resistance and higher water permeability between treatments, respectively. The effect of inter-row tillage on potato yield was significant so subsoiling and chiseling had a higher potato yield between treatments, respectively. The effect of irrigation water rate on potato yield was not significant. The effect of inter-row tillage on water use efficiency wasn’t significant.

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Comparison of the land suitability variations among the soil map units in viewpoint of pedodiversity indices may provide a good assessment of the soil mapping precision. The main objective of this study was to assess the significance of functional pedodiversity thorough two detailed map units for irrigated wheat and potato for class and subclass levels of suitability in the Faradonbeh plain, using Shannon and Simpson indices. First, soil samples at 35 and 47 sampling sites in the D and E map units, respectively, were collected from the depths of 0-25, 25-50, 50-75 and 75-100 cm. Then, the qualitative land suitability class and subclass of all sampling points for each studied land use, was evaluated based on simple limitation method. Although both indices showed higher values in the subclass level of suitability, but the average functional pedodiversity of the studied map units, indicate a significant difference (95% confidence level), just in this suitability level. It was observed that the significance of the pedodiversity indices is not influenced by the land use type or the analyzed diversity index. Hence, as a supplementary procedure to study the intra-unit variation of the soil maps, use of diversity indices may provide some worthwhile information