Peyman Jafari; Amirhooshang Jalali
Abstract
Introduction: Spinach (Spinaciaoleracea L.) is considered as a green leaf with fresh and canned consumption, a significant source for vitamin C, vitamin A, carotenoids, flavonoids, folic acid, calcium and magnesium.According to statistics, 4479 hectares of Iran agricultural land were devoted to spinachand ...
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Introduction: Spinach (Spinaciaoleracea L.) is considered as a green leaf with fresh and canned consumption, a significant source for vitamin C, vitamin A, carotenoids, flavonoids, folic acid, calcium and magnesium.According to statistics, 4479 hectares of Iran agricultural land were devoted to spinachand the average yield per hectare is equal to 42.18(FAO, 2014).Different regions of Iran havegenetic diversity of the spinach landraceand cultivation of this plant relieson the use of the landraces.Among the different spinach landraces, a landracescalled seed barbed (Spiny), has a significantimportancebecause of some desirable characteristics.Thisstudy was conductedfor comparison of five spinach landracein Isfahan, showedthat spiny seed Varamin with 47.8 tons per hectare fresh yield allocated the highest yield.The number and size of leaves and side branches are the most important components of plant yield.Due to the fact that about 70 percent of total dietary nitrate intake per person per day will be provided through the leafy vegetables,considering the amount of accumulated nitrate in spinach is very important.To evaluate the yield and yield components of eight Iranian spinachlandrace, and two varieties of leafy American and German experiment was conducted for two years.
Materials and Methods This research was performedfor two years, in Kabootarabad Agricultural Research Station of Isfahan to evaluate the yield and yield components of eight Iranian spinachlandraces(Varamin prickly seed, Sari, Ghaemshahr, Babul, Kashan, Najaf Abad, Varamin 88 andArdestān), and two American and German leafy cultivars. Randomized complete block design with three replications was usedfor each year and the results were reported based on two-year combined data analysis. In full leaf development stage and before the harvest of each plot, 10 plants randomly were selected and measured attributes: number of leaves, leaf length, leaf width and length of the petiole. In order to assess yield, after removing two distance of half a meter from each side, two central rows of plants per plot (surface equivalent to two square meters) were analyzed. Nitrate content of samples wasanalyzed using ion analyzer. Data statistical analysiswas performed using SAS software and means were compared by Duncan’s multiple rangetest at 5% probability level.
Result and DiscussionsYield, leaf length, petiole length and height (at 1% statistical probability level) and number of leaves and nitrate content (at 5% statistical probability level) were statistically significant. Spiny seed Varamin with 53.49 t ha-1 fresh yield, produced to the highest yield. In other research according to the environmental conditions and variety, spinach fresh yield have been reported from 18.6 to 44.8 t ha-1. It looks different mass spinach; produce the highest yield in specific geographic environments. In a similar study that was conducted underIsfahan weather conditions, spiny seed Varaminlandraceproduced 47 830 kg ha-1 fresh yield. Range in plant height was from 24 cm to 30.33 cm in Najaf Abad, and Sari landraces, respectively. When spinach was encountered with optimal climate conditions, achieved the maximum height that led toa positive impact on fresh yield. Ardestānlandrace produced the lowest number of leaves (10.67)among the landraces/varieties had been studied. In a similar study of 29 spinach genotypes the leaf number were varied from 12 to 23. Petiole length range between varieties/landraces was from 9.84 to 18.33 cm. Although the petiole length, is a desired trait for mechanized harvesting, but in case of improper management of nitrogen fertilizer can be considered as an undesirable trait. Leafy Varaminlandracewith 231 and 462 ppm nitrate in blade and petiole, respectively, had the lowest and German cultivar with 583 and 1182 ppm nitrate in blade and petiole, respectively, had the highest nitrate accumulation. Despite the differences between the varieties/landraces,the contentof nitrate in petioles was greater than the leaf blade (about 1.6 times) in spinach. Higher concentrations of petiole nitrate compared to the blade considered in many research, and in caseof poor management fornitrogen fertilizers, it may increase up to6 times. In any case, leafy cultivars such as German have been modified for mechanized cultivation and have long petiole with nitrate content. That's why their petioles are separated in the industrialprocessing. It is better fresh petioles of spinach isolated or sufficiently boiled to reduce nitrate levels. According to the results obtained in this study among the examined populations of spiny seed Varaminlandraces, leafy Varamin, Najaf Abad, and Sari can produce yields similar toGerman variety and so are suitable for the production of spinach in Isfahan province.
Peyman Jafari; Amirhooshang Jalali
Abstract
Introduction: The fresh, steamed and boiled spinach were used because of antioxidant compounds that have great biological value. This plant is usually rich in nitrates that can play an important role in reducing heart attacks. Each year, more than 30% of the area under cultivation leafy vegetables in ...
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Introduction: The fresh, steamed and boiled spinach were used because of antioxidant compounds that have great biological value. This plant is usually rich in nitrates that can play an important role in reducing heart attacks. Each year, more than 30% of the area under cultivation leafy vegetables in Iran, was allocated to spinach. Spinach growing in both spring and autumn or summer, has poor quality due to stem production. Higher spinach yield have been reported in autumn cultivation (compared to spring or winter planting). The nitrogen-rich lands, little light condition, excessive use of nitrogenous fertilizers and plants during the growing season short cause some plants like spinach, are faced with the problem of nitrate accumulation. The accumulation of nitrate in vegetables will be different depending on the species and genetic differences.
Materials and Methods: This research was conducted for two years in Kabootarabad Agricultural Research Station of Isfahan in order to determine the most suitable planting prickly seed spinach. Each year, of experiment was based on randomized complete block design with four replications and the results were reported based on two-year combined data analysis. Five planting dates at intervals of 15 days from the beginning of September had been adjusted. Prickly seed spinach was prepared from Seed and Plant Improvement Institute. In full leaf development stage and before the harvest of each plot, 10 plants randomly were selected and measured attributes including number of leaves, leaf length, leaf width and length of the petiole. In order to assess yield, two central rows of plants per plot (surface equivalent to two square meters) were analyzed after removing two distance of half a meter from each side. Nitrate samples were analyzed using ion analyzer. Statistical analyses of the data, correlated traits were performed using SAS software and comparisons of means using LSD at 5%.
Result and discussion: According to the results, year had no significant effect on traits. 5 September sowing date, GDD=571 was diagnosed as the best spinach planting date yielding 43 tons per hectare. Delayed planting date of 5 September to 22 October showed significant yield reduction and the amount of nitrate accumulation in plants also increased linearly. Number of leaves can be changed as one of the main factors influencing the performance of spinach according to cultivar and environmental conditions and in some studies they were ranged from 12 to 23. Amounts of nitrate accumulation in spinach were 2675, 2898, 3189 and 3571 ppm of fresh weight in different planting date of 5 September (571 GDD), 22 September (354 GDD), 6 October (193 GDD) and 22 October (84 GDD), respectively. The different sowing date, petiole nitrate accumulation varied from 3513 to 4680 ppm. Nitrate accumulation was ranged from 2135 to 3125 ppm wet weight in leaf blade. Different planting dates can influence on the length of day and intensity of light and thus can affect the amount of nitrate in plant. After planting date of August 22, temperature and radiation also reduced, and therefore it is natural that reduce the activity of the enzyme nitrate reductase and be more prepared conditions for nitrate accumulation. According to the World Health Organization, the uptake of nitrate and nitrite per kg of body weight daily allowance, equal to 0.06 and 0- 7.3 mg has been reported. The quality of light received by the plant also had an effect on nitrate accumulation, and red light compared to blue light has a greater role in stimulating the enzyme nitrate reductase activity and thus is more effective in reducing nitrate accumulation.
Conclusion: Climatic conditions affect the quantity and quality of vegetative organs. The results of this study showed that unsuitable spinach planting date will reduce not only yield, but also increases the concentration of nitrate (over 2500 ppm of fresh weight) and it may causes risks for consumers.
Peyman Jafari; Amirhooshang Jalali
Abstract
Introduction: Spinach is one of the most important leafy vegetables, rich in calcium, phosphorus, potassium, vitamin C and B-carotene, and it is likely to be Iran's origin. More than 30 percent of the area under cultivation of in Iran leafy vegetables, allocated to spinach plant. Spinach is a cool season ...
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Introduction: Spinach is one of the most important leafy vegetables, rich in calcium, phosphorus, potassium, vitamin C and B-carotene, and it is likely to be Iran's origin. More than 30 percent of the area under cultivation of in Iran leafy vegetables, allocated to spinach plant. Spinach is a cool season crop and its cultivation is done in the fall and in early spring. Various regions of Iran, has the vast genetic diversity in relation to the mass of spinach. In a study to evaluate the yield and agronomic traits spinach 121 mass Iran, the masses were divided into six clusters that each cluster has specific morphological and agronomic traits. Leafy vegetables, especially spinach are the main sources of nitrate absorption and about 70 percent of total dietary nitrate intake per person per day is provided by leafy vegetables.
Material and Methods: To study the preliminary agronomic and morphological traits and nitrate amounts of 100 Iranian spinach mass are available in GenBank, an investigation was carried out in Agriculture and Education Center Research in Esfahan for two years (2013-2014) by using of five mass dominant cultivars, and two control landrace (Varamin 88 and Varamin prickly seed). The aim of the first year of the study was the primary isolation of superior landraces based on agronomic traits of spinach. At the end of the first year of growth, seed traits, including the type (smooth-prick), the width of the blade, leaf color, wrinkling of leaf area, leaf thickness, the petiole (standing, half-standing and sleeping), petiole length, shape of leaf, the shape of the leaf tip, bolting during plant growth and the number of male and female were determined. A total of 25 landraces selected in the first year of study were compared in the second year using a randomized complete block design with three replications. Studied traits were: yield, dry matter yield, number of leaves, leaf length, leaf width, and petiole length and nitrate levels. Statistical analyses of the data, correlated traits were performed using SAS software and comparisons of means calculated by using LSD at 5%.
Result and Discussion: The results showed that 21.5% of the populations used in this study had the petiole with a standing (vertical) position and 25.2% of them had a long petiole. Length of the petiole and hoisted were considered desirable trait for mechanized harvesting. However, varieties have high nitrate concentrations, or in cases where the management of nitrogen fertilizers does not do well, longer tail leaves are an undesirable trait because the accumulation of nitrate in the tail leaves is more than leaf spinach. 35.5% of spinach leaves landrace used in this study were green color. Leaf color in leafy vegetables is very important. Leaf length, have a range of 11 cm in the Kashan, up to 18 cm in mass TN-69-101 (collected from Lorestan). In this study the agronomic characteristics of the mass of the spinach, length of leaf blade mass in Kashan, Shahreza and Najaf Abad, were 15.50, 11.50, and 9.50 cm, respectively, and all three populations were significantly different in this respect. A significant positive correlation was observed between leaf length and leaf width (0.78**). The highest of fresh yield was 32.59 t ha-1 and produced by Varamin 88 that with six masses (TN-69-73, Varamin- prickly, TN-69-74, TN-69-153, TN-69-140, TN-69-58) did not differ statistically. Three populations of TN-69-153, TN-69-140 and Varamin- prickly (advanced masses prickly Varamin) both in terms of fresh and dry matter yield were superior. The (TN-69-78) mass with 17 leaves, the highest, and (TN-69-22) mass with 11/33 leaves, the lowest number of leaves produced among the different masses. Leaf blade width in the mass TN-69-31, was equal to 12/38 cm and with the eleven other populations had a significantly blade width more than other the masses. In terms of nitrate in shoots, TN-69-153 population with 1708 mg of nitrate per kg of dry matter had the highest amount of nitrate.
Conclusion: The results of this study showed that considering the diversity traits among different populations of spinach in various parts of the Iran can be provide suitable potential for agronomic and breeding purposes. The masses after selection and purification can be available to farmers and producers.
