Soil science
Mansour Mirzaei Varouei; Sh. Oustan; A. Reyhanitabar; N. Najafi
Abstract
Introduction
Savory is considered one of the most important medicinal plants, which is used in various food and medical industries. Nitrogen (N) plays a major role on the growth and yield of medicinal plants. Therefore, an adequate supply of N is required for successful production of savory. However, ...
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Introduction
Savory is considered one of the most important medicinal plants, which is used in various food and medical industries. Nitrogen (N) plays a major role on the growth and yield of medicinal plants. Therefore, an adequate supply of N is required for successful production of savory. However, the application of chemical N fertilizers is associated with many obstacles such as groundwater pollution, N enrichment of surface waters, and drop in the quality of plants. Accordingly, nowadays, great attention has been paid to organic fertilizers. In this regard, humic acid-based fertilizers have shown promising results. Humic acids (HAs) could be converted into nitrohumic acids (NHAs) through the nitration process, in which nitro groups (NO2) are located on the aromatic rings. This process increases the N content of the HA. Thus, NHAs can be used as organic N fertilizers in the cultivation of medicinal plants whose organic production is a priority. However, the effects of these types of fertilizers on plant growth and physiological characteristics have not been well understood. Accordingly, the present study for the first time investigates the effectiveness of NHA on the morphological and physiological characteristics of savory, as well as N loss through leaching.
Materials and Methods
In the current study, HA was initially extracted from leonardite (purchased from Yazd Golsang Kavir Company) as a rich source of HA. Then, NHA was prepared through the nitration process using nitric acid (50% by volume). After that, using FT-IR (Fourier transform infrared spectroscopy) and CHNS analysis the extracted HA and NHA were characterized, and their N content was determined. Afterward a greenhouse experiment in a completely randomized design (CRD) with three replications was conducted to determine the effects of 16 treatments, including control (without urea, HA and NHA), urea (U1, U2 and U3), humic acid (HA1, HA2 and HA3), nitrohumic acid (NHA1, NHA2 and NHA3), urea-humic acid (U1HA1, U2HA2 and U3HA3), and urea-nitrohumic acid (U1NHA1, U2NHA2 and U3NHA3) on the morphological and physiological characteristics of savory plant. The treatment levels were determined as 40, 80, and 120 mg N kg-1 for the first, second and third level of the treatments, respectively. In the combined treatments of urea and HA or NHA, an equal fraction of the total nitrogen (N) was applied. At the end of the experiment, standard methods were used to assess various characteristics, including root length, leaf area, plant height, root volume, wet and dry weights of shoot and root, leaf chlorophyll index, concentrations of phosphorus, potassium, nitrogen, nitrate, and nitrate reductase in both the shoot and root. Additionally, leaching was conducted on specific days during the experiment, and the leachate was collected for nitrate measurement.
Results and Discussion
The results showed that using the nitration process, some characteristics of the NHA such as total acidity, the content of carboxylic and phenolic groups as well as N content improved as compared to the initial HA. Moreover, the results indicated that most of the morphological and physiological traits of savory plants, including leaf area, plant height, root length, fresh and dry weights of root and shoot as well as chlorophyll index, and the concentration of nitrogen, phosphorous, potassium, nitrate and nitrate reductase enzyme were significantly higher in the NHA treatments than those of HA. In addition, the highest shoot dry weight was obtained in the combined treatments of U3NHA3 and U3HA3 as well as in the U3 treatment alone. The average rate of nitrate concentration increase in the U treatments was 1.77 times higher than the UNHA treatments. According to the results, U3 treatment indicated the highest nitrate loss which by using the U3NHA3 treatment, the mean concentration of nitrate in the leachate decreased by about 40.5% as compared to the U3 treatment.
Conclusion
The findings of this research revealed that most of the morphological and physiological traits of savory plant showed better responses to the combined treatments of U3NHA3 and U3HA3 as well as to the U3 treatment alone. However, with regard to the lower accumulation of nitrate in the shoot of savory as well as to the lower nitrate leaching, the combined treatments were preferred. Accordingly, NHA can be a alternative nitrogen source in increasing the yield and growth indicators of savory. However, the reasons behind the fact of the better performance of combined nitrogen treatments than the individual ones require more research in the future.
Nosratollah Najafi; Rashed Ahmadinezhad; Naser Aliasgharzad; Shahin Oustan
Abstract
Introduction: Chemical fertilizers can supply all the nutrients required by plants, but their high consumptions cause environmental pollution and increased agricultural production costs. Organic fertilizers can improve the biological, physical, and chemical properties of soil and improve soil fertility ...
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Introduction: Chemical fertilizers can supply all the nutrients required by plants, but their high consumptions cause environmental pollution and increased agricultural production costs. Organic fertilizers can improve the biological, physical, and chemical properties of soil and improve soil fertility and productivity. However, these fertilizers alone cannot provide all the requirements of plants for different nutrients. In addition, these fertilizers are not sufficiently available to farmers everywhere. So, in order to increase effectiveness of organic and chemical fertilizers, to decrease environmental pollutions and to achieve sustainable agriculture, integrated application of organic and chemical fertilizers is recommended. Nitrogen (N), phosphorus (P) and potassium (K) are essential elements for plant nutrition and growth. Wheat as a strategic crop is the most important cereal and plays a very important role in human and animal nutrition and health. The deficiencies of N, P and K in the most agricultural soils often reduce the growth and yield of wheat. Therefore, the appropriate concentrations of these nutrients in wheat seed, leaf and stem are important not only for the optimum growth of the wheat plant and its quality improvement but also for the health of humans and animals.
Materials and Methods: This research work was carried out to study the effects of combining farmyard manure (FYM), municipal solid waste compost (MSWC) and municipal sewage sludge compost (MSSC) with different levels of urea on seed, leaf and stem yields of wheat (Triticum aestivum L.) cultivar Alvand and concentrations of N, P and K in seed, leaf and stem in a randomized complete blocks design with 15 treatments and three replications under field conditions at Khalatposhan Agricultural Research Station, University of Tabriz, Tabriz, Iran. The treatments included were: 1) control (without fertilizers), 2) 150 kg urea/ha, 3) 300 kg urea/ha, 4) 30 ton MSWC/ha, 5) 30 ton MSWC/ha + 150 kg urea/ha, 6) 60 ton MSWC/ha, 7) 60 ton MSWC/ha + 150 kg urea/ha, 8) 30 ton MSSC/ha, 9) 30 ton MSSC/ha + 150 kg urea/ha, 10) 60 ton MSSC/ha, 11) 60 ton MSSC/ha + 150 kg urea/ha, 12) 30 ton FYM/ha, 13) 30 ton FYM/ha + 150 kg urea/ha, 14) 60 ton FYM/ha, 15) 60 ton FYM/ha + 150 kg urea/ha. The size of each plot was 2.0m × 1.9m. At the end of growth period, the plants were harvested and different sections of wheat plant (seed, leaf and stem) were separated and the yield of each section was determined. The concentration of N in seed, leaf and stem were then measured by Kjeldahl method. After dry ashing of the seed, leaf and stem samples, the concentrations of P and K in their extracts were measured by spectrophotometer and flame photometer instruments, respectively.
Results and Discussion: The results showed that application of 300 kg urea/ha increased the wheat grain yield and concentrations of N, P and K in seed, leaf and stem but it decreased the stem yield. Application of 150 kg urea/ha had no significant effect on the leaf yield but its integration with 60 ton MSWC/ha significantly increased the leaf yield of wheat. The combining of 150 kg urea with 30 and 60 ton FYM, MSWC and MSSC per hectare increased yields of wheat stem and seed and their N and P concentrations as compared with the control and application of solely organic fertilizers. The use of FYM, MSWC and MSSC significantly increased the wheat grain yield and concentrations of N, P and K in seed, leaf and stem relative to the control but their effects on yields of leaf and stem depended on the type and rate of organic fertilizer. The highest yields of grain, stem and leaf and the highest concentrations of N, P and K in wheat grain, stem and leaf were observed under combined application of 150 kg urea and 60 ton FYM, MSWC and MSSC per hectare. The minimum yields of seed, leaf and stem and the minimum concentrations of N, P and K in different organs of wheat plant were observed in the control treatment. The average wheat yield component was in the order of seed > stem > leaf. The mean concentrations of N, P and K in different sections of wheat were in the order of seed > leaf > stem, seed > leaf > stem and stem > leaf > seed, respectively. The grain yield of wheat had positive and significant correlations (p<0.01) with concentrations of N, P and K in different organs of wheat, which indicates the role of N, P and K nutrition of wheat plant in increasing its seed yield.
Conclusions: The wheat seed had higher concentrations of N and P and lower concentration of K compared to leaf and stem. In general, in order to decrease nitrogen fertilizers use, enhance N, P and K nutrition of wheat plant, improve wheat seed quality, decline environmental pollution and increase wheat yield, application of 150 kg urea and 60 ton manure per hectare is recommended. However, if there is not enough manure, 150 kg urea and 60 ton municipal solid waste compost or municipal sewage sludge compost per hectare can be applied at similar conditions.
Sheyda Kaboodi; farzin shahbazi; Nasser Aliasgharzad; nosratola najafi; naser davatgar
Abstract
Introduction: Understanding soil biology and ecology is increasingly important for renewing and sustainability of ecosystems. In all ecosystems, soil microbes play an important role in organic matter turnover, nutrient cycling and availability of nutrients for plants. Different scenarios of land use ...
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Introduction: Understanding soil biology and ecology is increasingly important for renewing and sustainability of ecosystems. In all ecosystems, soil microbes play an important role in organic matter turnover, nutrient cycling and availability of nutrients for plants. Different scenarios of land use may affect soil biological properties. Advanced information technologies in modern software tools such as spatial geostatistics and geographical information system (GIS) enable the integration of large and complex databases, models, tools and techniques, and are proposed to improve the process of soil quality and sustainability. Spatial distribution of chemical and biological properties under three scenarios of land use was assessed.
Materials and Methods: This study was carried out in Mirabad area located in the western part of Souldoz plain surrounded by Urmieh, Miandoab, Piranshahr and Naghadeh cities in the west Azerbaijan province with latitude and longitude of 36°59′N and 45°18′E, respectively. The altitude varies from 1310 to 1345 with average of 1325 m above sea level. The monthly average temperature ranges from -1.4 °C in January to 24.6 °C in July and monthly precipitation ranges from 0.9 mm in July to 106.6 mm in March. Apple orchard, crop production field and rich pasture are three selected scenarios in this research work. Soil samples were systematically collected at 65 sampling points (0-30 cm) on mid July 2010. Soil chemical and biological properties i.e. microbial community, organic carbon and calcium carbonate equivalent were determined. The ArcGIS Geostatistical Analyst tool was applied for assessing and mapping the spatial variability of measured properties. The experimental design was randomized complete blocks design (RCBD) with five replications. Two widely applied methods i.e. Kriging and Inverse Distance Weighed (IDW) were employed for interpolation. According to the ratio of nugget variance to sill of the best variogram model three following spatial dependence conditions for the soil properties can be considered: (I) if this ratio is less than 25%, then the variable has strong spatial dependence; (II) if the ratio is between 25% and 75%, the variable has moderate spatial dependence; and (III) otherwise, the variable has weak spatial dependence. Data were also integrated with GIS for creating digital soil biological maps after testing analysis and interpolating the mentioned properties.
Results and Discussion: Spherical model was the best isotropic model fitted to variograms of all examined properties. The value of statistics (R2 and reduced sum of squares (RSS)) revealed that IDW method estimated calcium carbonate equivalent more reliably while organic carbon and microbial community was estimated more accurately by Kriging method. The minimum effective range (6110 m) was found for microbial community which had the strong spatial dependence [(Co/Co+C)
Solmaz Kazemalilou; Nosratollah Najafi; adel reyhanitabar
Abstract
Introduction: Sunflower as one of the most important oil crops in the world is affected by water deficit stress. Water deficit stress is one of the most important limiting factors of crops growth and production in Iran and many regions of the world. Because of the low water productivity in Iran, the ...
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Introduction: Sunflower as one of the most important oil crops in the world is affected by water deficit stress. Water deficit stress is one of the most important limiting factors of crops growth and production in Iran and many regions of the world. Because of the low water productivity in Iran, the water conservation and increasing of water use efficiency through good management including integrated application of organic and chemical fertilizers and balanced nutrition of plants are necessary. One of the negative effects of water deficit stress is impaired uptake of nutrients such as phosphorus (P) by plants and a decrease in plant yield. It has been found that use of P can reduce the negative effects of drought stress on plants that means the tolerance of plants to drought stress increases with optimal nutrition of P. In Iran, due to the lack of organic matter and the high cost of chemical fertilizers, farmers tend to use organic wastes such as sewage sludge that can have an important contribution in the improvement of soil fertility and plant nutrition and lead to an increase in water use efficiency. Also, integrated and suitable nutrition of plants is a method of sustainable management of soil fertility under environmental stresses. Therefore, this study aimed to evaluate the effects of sewage sludge (SS) and triple superphosphate (TSP) on sunflower (Helianthus annuus L. cv. Farrokh) seed yield and its components and determining the optimal levels of their consumption under optimum and limited irrigation conditions.
Materials and Methods: This experiment was conducted as a split-plot factorial arrangement in a randomized complete block design in Agricultural Research Station of Khoy under field conditions for two years. Experimental factors were irrigation time at two levels (irrigation after 60 and 150 mm evaporation from class A evaporation pan), triple superphosphate at three levels (0, 100 and 200 kg/ha), sewage sludge at four levels (0, 14.2, 28.4 and 56.7 t/ha) and year at two levels (2014 and 2015) with three replications. The 1000 seed weight of sunflower, weight and number of seeds per plant, the percentage of empty achenes, head diameter and seed yield were measured at the end of plant growth period. Statistical analysis of the data was performed using MSTATC software and means comparison was done by Duncan’s multiple range test at 5% probability level.
Results and Discussion: The combined analysis of variances showed that the effect of year was significant for weight of seeds per plant, head diameter and seed yield but it is not significant for 1000 seed weight, number of seeds per plant and percentage of empty achenes. Although water deficit stress significantly increased the percentage of empty achenes but 1000 seed weight, weight and number of seeds per plant, head diameter and seed yield significantly decreased compared to optimum irrigation conditions. The application of integrated application of 200 kg TSP and 56.7 tons SS per ha increased yield and yield components significantly compared to the control treatment. The interaction effects of TSP×SS×irrigation were significant for all studied characteristics. Under optimum irrigation condition, the highest 1000 seed weight (64 g), weight of seeds per plant (85 g), number of seeds per plant (1513), head diameter (22 cm) and seed yield (5576 kg/ha) were observed in intergrated treatment of 200 kg TSP+56.7 tons SS/ha. Under limited irrigation condition, the highest 1000 seed weight (57 g), seeds weight per plant (81 g), seeds number per plant (1494), head diameter (19.6 cm) and seed yield (5322 kg/ha) were obtained from 56.7 tons SS/ha treatment which showed no significant difference with 100 kg TSP+56.7 tons SS/ha treatment. Under optimum and limited irrigation conditions, the percentage of empty achenes were significantly decreased by integrated treatments of 200 kg TSP+56.7 tons SS/ha and 100 kg TSP+56.7 tons SS/ha (70 and 81 percent, respectively) compared to the control.
Conclusion: The results of this study indicated that integrated application of triple superphosphate and sewage sludge can mitigate negative effects of drought stress; therefore in order to reduce the use of chemical fertilizers, increasing sunflower seed yield and development of sustainable agriculture, integrated treatments of 200 kg TSP+56.7 tons SS/ha under optimum irrigation and 100 kg TSP+56.7 tons SS/ha under limited irrigation can be recommended at similar conditions (from the aspect of soil, plant, sewage sludge and climate).
siros sadeghi; Shahin Ostan; Nosratollah Najafi; Mostafa Valizadeh; Hassan Monirifar
Abstract
Introduction: Heavy metal contamination not only adversely affects the chemical properties, availability of nutrients and biological activity of the soils, but also causes serious risk to the human health from entering the food chain. Cadmium as an unnecessary heavy metal is highly toxic to plants. Cadmium ...
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Introduction: Heavy metal contamination not only adversely affects the chemical properties, availability of nutrients and biological activity of the soils, but also causes serious risk to the human health from entering the food chain. Cadmium as an unnecessary heavy metal is highly toxic to plants. Cadmium toxicity inhibits plant growth and even death. Metabolic processes such as photosynthesis and cellular respiration are disturbed due to cadmium toxicity. Among the heavy metals, zinc is an important nutrient in many biological processes such as photosynthesis, activity of antioxidant enzymes, proteins, hormones and other activities. Because of the similar chemical behavior of cadmium and zinc, interaction between the two metals is of interest to many researchers.
Materials and Methods: In this study, to investigate the interaction effects of cadmium and zinc on shoot and root dry matter and chemical composition of corn (Zea mays cv. single cross 704), a factorial experiment as a randomized complete block design in triplicate with eight levels of cadmium (zero, 0.5, 2.5, 5, 10, 20, 40 and 80 mg Cd kg-1) and eight levels of zinc (zero, 5, 25, 50, 100, 200, 400 and 800 mg Zn kg-1) was conducted in a loamy sand soil under greenhouse conditions. After 60 days, the plants were harvested and dry weights of shoots and roots were determined. Moreover, after wet digestion, the concentrations of cadmium, zinc, iron, manganese and copper in these tissues were determined by flame atomic absorption spectrometry (Shimadzu-6300).
Results and Discussion: Treatments with 800 mg Cd kg-1 showed symptoms of cadmium and or zinc toxicity at early stages of the growth. These plants died after 10 to 20 days of germination. The results showed that the cadmium and zinc interactions on shoot and root dry weights were significant. At 0.5, 2.5, 20 and 80 mg Cd kg-1 (except for Cd0.5-Zn25), application of 5 to 50 mg Zn kg-1 increased shoot dry weight. Higher levels of zinc supplementation exhibited adverse effects. At 5 and 10 mg Cd kg-1, supply of 5 to 100 mg Zn kg-1 was associated with an increase in shoot dry weight, but shoot growth was reduced at higher zinc levels. At 40 mg Cd kg-1, application levels of 5 to 200 mg Zn kg-1 increased shoot dry weight, whereas 400 mg Zn kg-1 showed adverse effects. Moreover, the cadmium and zinc interactions on chemical composition of corn were significant. Based on the results, at low levels of cadmium, zinc supplementation at each level increased the shoot and root cadmium concentrations, while at high levels of cadmium, low and high zinc supply caused a decrease and increase in the shoot as well as root cadmium concentrations, respectively. The concentration of a particular trend was observed on the shoot and root. Supplementation of zinc at each level of cadmium (except for 80 mg Cd kg-1), first increased and then decreased the iron concentration of shoots and roots. Application of zinc at each level of cadmium decreased manganese and copper concentrations in shoots and roots.
Conclusions: According to the results, the ecological tolerance of corn to zinc was found to be 800 mg Zn kg-1. Also, the application level of zinc with positive effect on shoot dry weight increased with an increase in cadmium level. At all levels of cadmium, supplementation of zinc at medium levels prevented the accumulation of cadmium in shoots, while high and low levels of zinc intensified the cadmium accumulation. The highest accumulation of cadmium in roots was occurred at highest level of zinc. Zinc supplementation at each level of cadmium first increased and then decreased iron concentration in shoots and roots. However, zinc supply at each level of cadmium decreased copper and manganese concentrations in shoots and roots. As a conclusion, zinc at low levels diminished toxic effects and accumulation of cadmium, meanwhile high levels of zinc not only did not control cadmium but showed deleterious effects. The critical level of poisoning for cadmium in aerial parts of both plants in lower density in the soil (up to 90 mg kg-1 ) showed very little changes, but in higher density, it decreased in brassica napus and increased in zea mays. The critical level of poisoning on the aerial parts of both plants showed very little change with increasing the total density of cadmium in the soil.
rahim motalebifard; Nosratollah Najafi; Shahin Oustan
Abstract
Introduction: In natural environments, plants are subjected to biotic (insects, bacteria, fungi, and viruses) and abiotic (light, temperature, water availability, nutrients, and soil structure) stresses that can have negative effect on growth, metabolism, and yield. Among these, drought is a major abiotic ...
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Introduction: In natural environments, plants are subjected to biotic (insects, bacteria, fungi, and viruses) and abiotic (light, temperature, water availability, nutrients, and soil structure) stresses that can have negative effect on growth, metabolism, and yield. Among these, drought is a major abiotic factor that limits agricultural crop production. Potato production has fourth rank in the world after rice, wheat, and maize with the production of 321 million tons from 19.6 million hectares. By about 3 percent of cultivation area, potato had 7.2 percent of total agricultural production (5.57 million tons) in our country (Iran). Limited studies have been conducted on the interactive effects of Zn and P on potato tubers quality under water deficit conditions.
Materials and Methods: This study was conducted for evaluating the effects of soil moisture, phosphorus (P) and zinc (Zn) levels on the chemical composition and nutrients content of potato (Solanum tuberosum L. cv. Agria) as a factorial experiment based on randomized complete blocks design with three factors under greenhouse conditions. The study was performed with factors of Zn at three levels (0, 10 and 20 mg Zn per kg dry soil as ZnSO4.7H2O), P at three levels (0, 30 and 60 mg P per kg dry soil as Ca(H2PO4)2.H2O (monocalcium phosphate)) and soil moisture at three levels (0.5FC-0.6FC, 0.7FC-0.8FC and 0.9FC-FC) using three replications and 81 pots. The soil moisture levels were imposed three weeks from the flowering (64th day) until harvest (85th day after planting). After imposing of soil moisture levels and at the harvest, the yield and yield components, reducing sugars concentration in fresh weight by di- nitro phenol method (Mostofi and Najafi, 2005) and starch by Antron method (Mostofi and Najafi, 2005), N, P, K, Mg, Na, Fe and Zn concentrations in dried potato tubers were measured. Data were subjected to analysis of variance as factorial 3×3×3 with n=3 by using MSTATC software. Duncan's multiple range tests at p≤0.05 probability level was applied to compare the mean values of measured attributes. The Excel software was used to draw Figures.
Results and Discussion: The results showed that water deficit significantly affected most of qualitative attributes and nutrients concentration of potato Tuber N, P and reducing sugar concentrations were significantly increased (p
Adel Reyhanitabar
Abstract
Knowledge about the P critical level and plant response to application of P can effectively help with the proper use of this element. In this study, P critical level for corn (Zea mays L.) was determined in 25 combined soils samples from corn fields of East Azerbaijan province during 2011-2012. Corn ...
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Knowledge about the P critical level and plant response to application of P can effectively help with the proper use of this element. In this study, P critical level for corn (Zea mays L.) was determined in 25 combined soils samples from corn fields of East Azerbaijan province during 2011-2012. Corn have been cultivated in two level of P (zero and 40 mg P kg-1) as a factorial experiment in a randomized complete blokes design with three replications .After 60 days, the plant growth parameters in shoot and root were measured. According to the results, in studied soils, clay content ranged from 12.4 to 57.3 with a mean 31.1 %. Calcium carbonate equivalent ranged from 7 to 35 with a mean 21.5 % and active calcium carbonate ranged from 1.47 to 10.78 with a mean 5.1 %. Application of P significantly increased shoot and root dry weight and their P content. According to the results, applied phosphorus levels, soil type and their interaction had a significant effect on corn growth parameters. Critical level of soil P for corn with Olsen-P, based on 90% relative yield, was determined 12, 14.44 and 10.46 (mg P kg-1 soil) by using graphical Cate–Nelson, Cate–Nelson analysis of variance and Mitscherlich-Bray methods, respectively. Mitscherlich-Bray equation coefficient C1 and C2, for Olsen-P, were 0.0956 and 0.0073 (kg soil mg-1P) respectively. Dry weight of shoot was positively and significant correlated with Olsen –P.
Z. Lotfi Arpachaei; Abazar Esmali; kazem hashemimajd; n n
Abstract
In modern agriculture, the preparation of soil fertility map seems to be necessary to plan for appropriate using of fertilizers for crops. This study was conducted to prepare a distinct map for evaluating soil fertility according to soil chemical properties in 136 soil samples of Ardabil plain in Ardabil ...
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In modern agriculture, the preparation of soil fertility map seems to be necessary to plan for appropriate using of fertilizers for crops. This study was conducted to prepare a distinct map for evaluating soil fertility according to soil chemical properties in 136 soil samples of Ardabil plain in Ardabil province. To achieve this purpose, the available K and P, total N, EC, pH and organic matter of soil were mapped using geostatistical Kriging estimator into Geographic Information System (GIS) by ArcGIS9.3 software. The Analytical Hierarchy Process (AHP) was used for weighting soil fertility factors as the input data. Then a membership functions was defined for each factor by factorial scoring and the map of soil fertility was prepared and classified for wheat and potato by using AHP technique into GIS program. The results showed that 74.84, 3.59, 19.3 and 2.32 percentage of lands for wheat cropping were classified based on soil fertility into groups of weak, moderate and suitable, respectively while for potato it was 24.88, 27.57, 7.19 and 40.34 percentage, respectively. As a final result, this type of distinct soil fertility map for different crops could assist us to manage the appropriate using of lands and fertilizers.
N. Najafi; S. Mardomi; Sh. Oustan
Abstract
In a greenhouse experiment, the effects of waterlogging, sewage sludge and manure on the uptake and concentrations of P, K, Ca, Mg and Na in root and shoot of sunflower (Helianthus annuus L.) were investigated. A factorial experiment based on completely randomized design with three replications including ...
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In a greenhouse experiment, the effects of waterlogging, sewage sludge and manure on the uptake and concentrations of P, K, Ca, Mg and Na in root and shoot of sunflower (Helianthus annuus L.) were investigated. A factorial experiment based on completely randomized design with three replications including duration of waterlogging at five levels (0, 2, 4, 8, 22 days), source of organic fertilizer at two levels (manure and sewage sludge) and each at three levels (0, 15, 30 grams per kg of soil) was conducted. The results showed that by increasing the duration of soil waterlogging, the P and K uptake and concentration in shoot and root, the concentration of Ca and Na in root, the Mg concentration in shoot, the uptake of Ca and Mg in root and the uptake and concentration of Na in shoot increased but P uptake and concentration in root and K uptake in root and shoot decreased again. By increasing the duration of soil waterlogging, the uptake and concentration of Ca in shoot decreased but the Ca concentration in shoot increased again. The effect of soil waterlogging on the Mg uptake in shoot was not significant. By application of sewage sludge and manure and increasing their amounts, the uptake and concentration of P in shoot and root, the uptake of Ca in shoot and root and the uptake and concentration of Na in shoot increased. The K uptake and concentration in shoot increased by application of manure and increasing its level while decreased by application of sewage sludge. The effect of soil waterlogging on the macronutrients and sodium uptake and concentrations in root and shoot was dependent on the source and amount of organic fertilizer and vice versa. The results demonstrated that even short periods of soil waterlogging (2 days) had considerable long-term effect on the concentrations of elements in plant. Generally, sunflower plant accumulated P, Mg and Na in root and Ca in shoot while the K concentration in root did not differ with shoot significantly.
N. Najafi; S. Mardomi
Abstract
چکیده
تأثیر مدت غرقاب شدن خاک، منبع و مقدار کود آلی بر ویژگی های رشد گیاه آفتابگردان ((Helianthus annuus L. در شرایط گلخانه ای بررسی گردید. آزمایش به صورت فاکتوریل و در قالب طرح ...
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چکیده
تأثیر مدت غرقاب شدن خاک، منبع و مقدار کود آلی بر ویژگی های رشد گیاه آفتابگردان ((Helianthus annuus L. در شرایط گلخانه ای بررسی گردید. آزمایش به صورت فاکتوریل و در قالب طرح پایه کاملاً تصادفی با سه تکرار شامل مدت غرقاب در پنج سطح (0، 2، 4، 8، 22 روز) و منبع و مقدار کود آلی در پنج سطح )شاهد، 15 گرم کود گاوی، 30 گرم کود گاوی، 15 گرم لجن فاضلاب و 30 گرم لجن فاضلاب بر کیلوگرم خاک( انجام شد. نتایج نشان داد که با افزایش مدت غرقاب شاخص کلروفیل برگها، وزن تر و خشک ریشه و بخش هوایی و نسبت وزن خشک بخش هوایی به ریشه کاهش یافتند ولی ارتفاع گیاه و قطر ساقه در محل طوقه افزایش یافتند و سطح برگها تغییر معنی داری نکرد. با کاربرد هر دو کود آلی شاخص کلروفیل، سطح برگها، قطر ساقه در محل طوقه، وزن تر و خشک ریشه و بخش هوایی و نسبت وزن خشک بخش هوایی به ریشه افزایش یافتند ولی ارتفاع گیاه تغییر معنی داری نکرد. اثر متقابل غرقاب و کود آلی بر شاخص کلروفیل برگها، سطح برگ و نسبت وزن خشک بخش هوایی به ریشه معنی دار بود ولی بر سایر صفات مورد مطالعه معنی دار نبود. بیشترین وزن تر بخش هوایی و ریشه و سطح برگها در تیمار بدون غرقاب و کاربرد 30 گرم لجن فاضلاب بر کیلوگرم خاک مشاهده گردید. لجن فاضلاب رشد بخش هوایی و ریشه آفتابگردان را بیشتر از کود گاوی افزایش داد. حساسیت ماده خشک بخش هوایی آفتابگردان به تنش غرقاب بیشتر از ماده خشک ریشه بود.
واژه های کلیدی: آفتابگردان، رشد، غرقاب، کود آلی، لجن فاضلاب
