Soil science
Z. Khanmohammadi; A. Ahmadi
Abstract
Introduction
Iranian shallot, scientifically known as Allium hirtifolium Boiss. is a perennial plant of the Allium genus and native to Iran. The Allium genus has many antioxidant properties due to its being rich in organic compounds of sulfur and phenol. The shallot is used to treat rheumatic ...
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Introduction
Iranian shallot, scientifically known as Allium hirtifolium Boiss. is a perennial plant of the Allium genus and native to Iran. The Allium genus has many antioxidant properties due to its being rich in organic compounds of sulfur and phenol. The shallot is used to treat rheumatic and inflammatory pains, soothe superficial wounds, treat some stomach diseases, be antispasmodic, and also as a spice and flavoring in some foods. Considering the health benefits of shallot and its application in the food industry, shallot corms are harvested from the natural resources in different stages of growth. Therefore, it is necessary to preserve the natural habitats of shallot and also supply the market demand for this plant. It appears that the cultivation of shallots within agricultural systems could serve as a significant strategy for meeting the demands of the expanding global market. Furthermore, shallots are known for their low water requirements, making their cultivation a focal point in Isfahan province in recent years. Additionally, this crop stands out as a high-income generator in the region. Despite its economic potential, there has been limited research into optimizing the growth conditions for this valuable plant. Hence, this study aimed to explore the impact of urea and cow compost on the yield of Iranian shallots in the Fereydun Shahr region, focusing on the uptake of nitrogen, phosphorus, potassium, and nitrates.
Materials and Methods
This research was carried out in the crop year of 1400-1401 in a field with an area of 300 square meters (32° 55' 53" N, 49° 56' 43" E) located in Fereydunshahr city of Isfahan province. The experiment was conducted according to a completely randomized design. Factorial arrangement of experimental treatments including two fertilization factors (urea and cow compost) was used. Plots with dimensions of 2 × 3 meters were created with a distance of 50 cm between the rows. The treatments were considered as urea fertilization at four levels (0, 120, 240 and, 360 kg ha-1) and cow compost treatment at three levels (0, 40 and, 60 tons ha-1). After plotting and applying cow compost treatments, shallot corms were planted at a depth of 10 to 15 cm in November 1400. Urea fertilizer treatment was applied in two stages, the first stage when the plant germinated (mid-April) and the second stage before flowering (second half of May). All treatments were applied in 3 replications. It should be noted that the treatments in this research are shown as 0-0 (control), 0-40, 0-60, 120-0, 120-40, 120-60, 240-0, 240-40, 240-60, 360-0, 360-40 and 360-60. The corms were harvested in June 1401 and the fresh and dry yield of the shallots was determined. The amount of nitrogen, phosphorus and, potassium in shallots was measured. Nitrate concentration was also measured in the harvested corms based on the Iranian national standard No. 4106. The nitrogen, phosphorus and, potassium uptake by shallots was obtained from the product of yield and the concentration of these elements. Results were analyzed using analysis of variance (ANOVA) procedure and the means were compared using the protected least significant difference (LSD) test at р < 0.05 probability level using SAS 9.3 software.
Results and Discussion
The results showed that the combined use of chemical fertilizer (urea) and cow compost has a significant effect on the shallot yield increment, as the highest yield was obtained in the combined treatment of urea fertilizer 240 (kg ha-1) and cow compost 40 (ton ha-1) application. Although the highest nitrogen concentration and uptake were observed in the treatment of 360 (kg ha-1) of urea along with 60 (ton ha-1) of cow compost, it was not significantly different from the treatment of 240-40 (the treatment with the highest yield). In general, the concentration of shallots nitrate was much lower than the permissible limit according to the national standard of Iran No. 16596. The highest nitrate concentration (24.63 mg kg-1 of fresh weight) was observed in the combined treatment of 120 (kg ha-1) of urea and 60 (ton ha-1) of cow compost application (120-60), which was significantly higher than other treatments. On the other hand, the concentration of shallots nitrate in the 240-40 treatment was significantly lower than the treatments of 360 kg of urea per hectare along with 40 or 60 (ton ha-1) of cow compost.
Conclusion
According to the results, to achieve the best yield, the most suitable level of urea application was 240 kg ha-1 and the best level of cow compost was 40 ton ha-1. It seems, utilization more amounts of urea or cow compost will only cause additional costs to the farmer and a waste of capital. Moreover, it can increase environmental pollution and nitrate concentration of product, which cause to quality decrement.
Irrigation
H. Shirvani Ichi; M. Ghobadinia; negar nourmahnad; Seyed Hassan Tabatabaei
Abstract
Introduction: Nowadays, the use of effluent in irrigation and especially drip irrigation systems has increased. The findings uncovered that drip irrigation is assumed as the only method which is capable of overcoming specific problems caused by wastewater usage. In this study, the efficiency of sand ...
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Introduction: Nowadays, the use of effluent in irrigation and especially drip irrigation systems has increased. The findings uncovered that drip irrigation is assumed as the only method which is capable of overcoming specific problems caused by wastewater usage. In this study, the efficiency of sand and geotextile filters with zeolite on wastewater properties and their application in the filtration of the drip irrigation system was investigated.
Materials and Methods: This study was conducted to investigate the changes in important chemical properties in the municipal wastewater of a university after passing through sand filters, geotextiles, and zeolites in the drip irrigation filtration system. A factorial experiment was performed in a completely randomized design with three replications. Treatments included sand filter (control-CTRL treatment), geotextile filter (G), sand filter with zeolite (SZ), and geotextile filter with zeolite (GZ). The sand used in this study was the usual silica sand which was in three sizes of 3-5, 5-8, and 8-12 mm. In order to remove any contamination and soil particles and increase the accuracy of the measurement of suspended solids in the effluent, the sands were washed several times with water before usage. The geotextiles used in this study had three types with weights of 300, 500, and 1000 grams per cubic meter. The zeolite used in this study was clinoptilolite modified with hydrochloric acid. The wastewater used in this study was obtained from the effluent of Shahrekord University. System flow rate, Pressure, nitrate, suspended solids, sodium, calcium, magnesium, electrical conductivity, effluent pH were measured before and after entering the filters at different hours. Statistical analysis was done by SAS software and the Duncan test was used to compare the means of the data.
Results and Discussion: The results showed that the sand-zeolite treatment had a good performance in terms of pressure and the geotextile-zeolite treatment was able to provide pressure for a short time. The amount of nitrate in the wastewater of the sand filter was not significantly different from the amount of inlet, but in other filters was significantly reduced. The amount of nitrate input of all treatments was 26 mg/l.The average output nitrate in the sand filter was about 25 and in the other filters was less than 20 mg/l. The average amount of suspended solids in the effluent was about 110 mg/l, while the average amount of suspended solids in the wastewater was reduced to less than 72 mg/l. The sand and sand-zeolite treatments increased the total amount of calcium and magnesium in the wastewater more than geotextile and geotextile-zeolite treatments, respectively. The average Ca + Mg of effluent in the total operating hours of the system was higher than the average input in all filters. The percentage of EC changes in total hours increased about 4% in sand and geotextile treatments and 14% in geotextile- zeolite and sand -zeolite filters. The highest percentage of pH changes was related to sand-zeolite filter, which reduced the pH of incoming wastewater by about 4.5%. After that, geotextile- zeolite filter reduced the pH of the incoming wastewater by 4%. The average pH of the effluent of all filters is lower than the average of their inlet.
Conclusion: Sand and geotextile filters alone cause pressure drop and dropper clogging. However, the sand-zeolite treatment has performed well in this regard. The geotextile-zeolite treatment has the potential to be used in terms of supplying the necessary pressure for a short period by applying special treatment measures before this filter. These conclusions are only in terms of pressure drop due to the ability of filters in practical use and do not refer to their ability to filter the parameters and provide the desired flow. All treatments, especially zeolite treatments, significantly reduced nitrate, and these filters can be used to reduce effluent nitrate in cases where the amount of nitrate is more than allowed. However, since the sand filter had no effect on nitrate reduction, the effluent must be treated for nitrate before using sand filters. The geotextile filter had a higher percentage of suspended solids removal at all hours. The addition of zeolites to both geotextile and sand base filters reduced their ability to treat suspended solids. Therefore, geotextile filters can be a good alternative to ordinary sand filters in terms of this parameter. All treatments increased Ca + Mg relative to the input. The sand- zeolite treatment reduced the pH of the incoming wastewater more than other treatments (about 4.5%). Also, desalination of salts from zeolite treatments increased the EC of effluent in the sand-zeolite and Geotextile- zeolite treatments. According to this study, the use of sand-zeolite in terms of reducing nitrate and suspended solid, increasing calcium and magnesium, and reducing pH and no pressure drop is recommended.
Z. Pashazadeh Laleh; H. Jafari; A.R. Vaezi Hir
Abstract
Introduction: The water is the major key in sustainable development, so it is necessary to be managed and conserved. The quality of surface water resources is mainly controlled by natural or geogenic factors including chemistry of recharge water, soil and geology processes, as well as the man-made contaminant. ...
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Introduction: The water is the major key in sustainable development, so it is necessary to be managed and conserved. The quality of surface water resources is mainly controlled by natural or geogenic factors including chemistry of recharge water, soil and geology processes, as well as the man-made contaminant. Qualitative indicators are used as effective managing tools in decision making programs. Water quality indices (WQI) are the simple and suitable tools to determine the quality statue of the water. In order to calculate the water quality index, many parameters are integrated in mathematical formula to represent the quality condition of the water with a number which classifies the quality in the scales of the weak to excellent. Many water quality indices were introduced by researchers and organizations around the world. Aji-Chay, one of the most important flowing rivers in East-Azerbaijan province, northwest of Iran, is passing through Tabriz plain in its way and finally ends to the Uremia lake. Regarding the focused industrial zones, agricultural field and urban areas in this plain, the river is highly vulnerable to pollution and quality degradation. So, this study was aimed to assess the Aji-chay River based on quality indicators, in order to helps its better management. Materials and Methods: In this research for assessing pollution of the Aji-Chay river using water quality indices, 16 sampling stations were located along the river and water samples were collected during wet (May 2016) and dry (September 2016) seasons. Electrical conductivity (EC), temperature, dissolved oxygen (DO) and pH were measured in the field and total dissolved solids (TDS), turbidity, major ions (Ca, Mg, Na, K, HCO3, Cl, SO4), nitrate (NO3), phosphate (PO4), biological oxygen demand (BOD), chemical oxygen demand (COD) and biological contaminants (fecal coliform) were determined in the laboratory. Quality indicators including the US national sanitary foundation water quality indices in the two forms of multiplicative (NSFWQIm) and additive (NSFWQIa) and Iranian surface water quality index (IRWQIsc) were used to assess the quality of the Aji-Chay river. Results and Discussion: Turbidity and Electrical conductivity (EC) is high at the upstream which is related to movement of the River in upper red formation (Miocene series) which enhances the chloride, sodium, calcium and sulfate. Arsenic concentrations are exceeding the drinking standards (0.01 ppm) across all samples mainly from a geogenic sources as well as discharge of wastewater in some areas. The elements Cd, Mn, Ni, Pb, Mo, Co, Zn, Fe and Al are mainly geogenic, whereas Cu, Ba and Cr are mostly originated from anthropogenic activities. Based on the results, river quality at the wet season is highly controlled by the main branch and Gomnab-Chay, but Mehran-rood plays the major role in downstream water quality at the dry season due to its higher discharge rate. The process was confirmed by Piper and Schoeller diagrams. Most of the parameters are increased in middle parts at the river where the concentrated sources of contaminates and discharge of wastewater increased the organic and biological constituents and nutrients especially in dry season. Assessing the river quality for agricultural uses based on modified Wilcox diagram shows except for Mehran-rood, the other samples are unsuitable for agriculture and the dry season quality is better than the wet season. Based on the results, increase in most parameters and so, pollution and quality degradation of the river are observed to the downstream. Assessing quality of the Aji-Chay river using US national sanitary foundation water quality indices in the two forms of multiplicative (NSFWQIm) and additive (NSFWQIa) and Iranian surface water quality index (IRWQIsc) confirmed the bad to very bad qualitative statue of the river in most stations especially in the middle parts of the Tabriz plain. The results revealed that quality degradation of Aji-Chay river is probably due to discharge of contaminants from municipal and industrial wastewaters (effluents), highlighting the need for managing actions to improve quality of this important river. Comparing the quality indices showed the priority of NSFWQIm (multiplicative form of US national sanitary foundation water quality indices) in quality classification and pollution assessment of the Aji-Chay river. Conclusion: Quality degradation of Aji-Chay river is probably due to discharge of contaminants from municipal and industrial wastewater effluents, indicating the need for managing actions to improve quality of this river. In this study priority of NSFWQIm (multiplicative form of US national sanitary foundation water quality indices) in quality classification and pollution assessment of the Aji-Chay river was confirmed.
Fatemeh Rakhsh; Ahmad Golcchin
Abstract
Introduction: Mobilization and stabilization of organic matter in soils represent a set of complex processes involving the processing and decomposition of organic matter by diverse communities of soil fauna and microorganisms, as well as chemical-physical interactions with mineral particles of soil. ...
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Introduction: Mobilization and stabilization of organic matter in soils represent a set of complex processes involving the processing and decomposition of organic matter by diverse communities of soil fauna and microorganisms, as well as chemical-physical interactions with mineral particles of soil. Clay minerals have high effects on the soil organic matter dynamics. Clay minerals with the physical protection of organic matter play an important role in reducing the rate of decomposition of organic matter. The effects of soil texture on the soil organic matter dynamics have been investigated in many studies, but the effects of exchangeable cations and clay types on mineralization of organic nitrogen and microbial biomass nitrogen have not been given much attention. For this reason, the aim of this study was to evaluate the effects of types and clay contents and exchangeable cations on the mineralization of organic nitrogen and microbial biomass nitrogen.
Material and Methods: Appropriate amounts of homoionic Na-, Ca- and Al- clays from Georgia kaolinite, Illinois illite and Wyoming montmorillonite were mixed with pure sand to prepare artificial soils with different clay contents, exchangeable cations, and clay types. The artificial soils have zero, 5 and 10% clay from Georgia kaolinite, Illinois illite and Wyoming montmorillonite that their clay minerals saturated with Ca, Na and Al. Alfalfa plant residues were incorporated into the artificial soils and the soils were inoculated with microbes from a natural soil and incubated for 60 days and concentration of NH4-N and NO3-N were measured every 15 days. In the artificial soil samples, microbial biomass nitrogen was measured by the fumigation-extraction method in the end time of incubation period.
Results and Discussion: The results of this study showed that the percentage of mineralized nitrogen in the two-month incubation period, was higher in the pure sand than in soils containing 5% and 10% clay, indicating that clay contents influence the capacity of soils to protect and store organic nitrogen. Microbial biomass nitrogen increased as the amount of clay in the soil increased. The highest and lowest amounts of microbial biomass nitrogen measured in soils with 10% clay (9.26 mg per 50 g dry soil) and pure sand (4.31 mg per 50 g dry soil), respectively. There was a significant influence of exchangeable cations on the percentage of mineralized nitrogen and microbial biomass nitrogen. The microbial biomass nitrogen and the percentage of mineralized nitrogen were highest in Ca-soils and lowest in Al-soils. The percentage of mineralized organic nitrogen in two months of incubation period was highest in soils with Georgia kaolinite clay and lowest in soil with Wyoming montmorillonite clay. The amounts of microbial biomass nitrogen in soils with Wyoming montmorillonite clay were lower than soils with Georgia kaolinite and Illinois illite clays. The percentage of mineralized organic nitrogen increased as the incubation period increased. The results of this study indicated that organic nitrogen mineralization rates and microbial biomass nitrogen were affected by types and clay contents and exchangeable cations and interaction of organic matter with clays and is an important process as it slows soil organic matter decomposition.
Conclusions: Mixing the alfalfa residues with artificial soils and incubation samples allowed to study the effects of types and clay contents and exchangeable cations on the percentage of NH4+-N, NO3--N, mineralized nitrogen, and microbial biomass nitrogen. Soils with different clay contents have different surface areas and cation exchange capacities; therefore, it is concluded that organic nitrogen storage of soils is, partly, controlled by the surface areas, cation exchange capacity and physical protection provided by the soils. Nitrogen mineralization and the amounts of microbial biomass nitrogen were different in soils with different exchangeable cations. It is concluded that exchangeable cations exert their influence on microbial biomass and hence nitrogen dynamics by controlling the size and activity of the microbial population through modifying the physicochemical characteristics of microbial habitats. Since various clay minerals have different specific surface areas and cation exchange capacity and the physicochemical changes induced in the soil environment as a result of variations of exchangeable cations is much greater in soils with higher cation exchange capacity and specific surface area. It seems the effects of clay mineralogy on the dynamics of organic materials and microbial biomass, in part, arise from the type of exchangeable cations present on the exchange sites of the clay minerals.
A. Hemati; H. A. Alikhani; M. Rasapoor; H. Asgari Lajayer
Abstract
Introduction: Recycling organic wastes has vital roles in sustainable agriculture, reducing pollutants in the environment, and nutrient enrichment of soils. Compost is the product of recycling organic waste through anaerobic treatment, which can be a good alternative.Again the use of chemical fertilizers ...
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Introduction: Recycling organic wastes has vital roles in sustainable agriculture, reducing pollutants in the environment, and nutrient enrichment of soils. Compost is the product of recycling organic waste through anaerobic treatment, which can be a good alternative.Again the use of chemical fertilizers is inappropriate. Vinasse is brown material and it is a product of industrial production of alcohol from molasses. Vinasse, a by-product of ethanol production from molasses, is a highstrength effluent with a high content of organics, mainly organic acids, reducing substances, cultured matter and glycerol. The wastewater is characterized by high concentrations of potassium, calcium, chloride and sulphate ions, a high content of suspended solids, a high CoD (Chemical oxygen Demand) level and a high temperature at the moment of generation.Vinasse can be used as a supplement for enhancing compost fertilizer quality, because it has plenty of organic matter and minerals. This research was done with the purpose of surveying application of vinasse in different levels on indices of compost producing (temperature, microbial population, nitrogen, carbon, the ratio C/N, nitrate, pH and EC) and producing time in different phases (during the production and after compost production) for 5 months in the waste resumption complex of Aradkooh in Tehran.
Materials and Methods: The method used for compost production from solid waste material was ventilating the fixed mass. In this research, the volume of ventilation was 0.6 lit air for 1 lit waste material in a minute.Four different treatments (each three replicates ) were applied to the compost:C0 without vinasse (control), C1, C2 and C3, respectively 10, 20 and 30 ml vinasse per kg waste material. The following factors were measured during each phase: Total-N was measured by the Kjeldahl method and organic carbon was measured by the Walkley-Black method. Thermometers were used for temperature monitoring at different locations in the riff-raff. The microbial population size was obtained by the CFU method.Electrical conductivity and pH of the water extracts from the samples were determined by shaking the samples mechanically with distilled water at a solid-to-water ratio of 1:10 (w/v). Additionally, NO3–N was determined by spectrophotometric method.
Results and Discussion: At the beginning of this study, theresults showed that, after the formation of the riff-raff, temperature was increasing rapidly all over the riff-raff, which indicates a specified microbial activity. Minimum time to reach the thermophilic temperature, 30 ml per kilogram of vinasse raw materials, was for (C3) and maximum of them was for the control treatment (C0). Adding vinass in the second phase led to an increase in the compost mass temperature. Treatment C3 with the highest and treatment C0 has the lowest microbial populations. Total nitrogen content increased during composting of the waste materials in comparison with its initial concentration. In both phases treatment C3 has the highest and treatment C0 has the lowest total nitrogen content. According to results of the measurements of organic carbon in the first phase, at the beginning of composting process, most of the organic matter was in treatment C3and the lowest organic matter was in C0. However, with increasing the composting process, the vinass treatment had lost jts organic carbon with more gradient. In the second phase by adding vinass, the originally organic carbon increased because of the high levels of organic matter. But,with further vinass treatment, they lost their organic carbon more vigorously. During five months,changes in the ratio of carbon to nitrogen C/Nwas variable. In vinass treatment, the ratio ofC/N increased more vigorously until it reached one quarter and then it fell less sharply. In the first month, this ratio fell less sharply in the control group, and in the final months it fell with more intensity. In the second phase, decreasing the ratio of carbon to nitrogen was observed and the decrease treatment was more than the other treatments. The monthly analysis of riff-raff samples showed that the higher increase in pH mostly occurs in the first month, and in all cases the value of the electrical conductivity increased during composting. Until the second month of pH and EC treatment, C3 and C2 increased and decreased in the third to fifth months.In the second phase pH at vinasse treatment increased and pH at C0 treatment decreased. Maximum amount of nitrate was observed at C3 treatment and at Epsom salt phase nitrate has the maximum amount.
Conclusion: Eventually, it is recognized that treatment C3 and C2it is adequate to add context of organic waste and this treatment decreases the production time of compost up to two months.The second phase was not suitable compared with the first phase due to the inability of increasing nitrate-nitrogen and pH.
M. Akbarzadeh; B. Ghahraman
Abstract
In geo-statistics, prediction of an unknown value of random field has been performed in specified time and position, using spatio-temporal Kriging. In some circumstances, a suitable covariate increase the estimation prediction. Geo-statistical methods of Universal Kriging (UK) and Kriging with External ...
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In geo-statistics, prediction of an unknown value of random field has been performed in specified time and position, using spatio-temporal Kriging. In some circumstances, a suitable covariate increase the estimation prediction. Geo-statistical methods of Universal Kriging (UK) and Kriging with External Trend (KwET) were applied to Mashhad plain water quality data sets. The optimal network to monitor groundwater quality was presented, using Entropy. All wells ranked based on the criterion of Entropy and mutual information. Then, the optimal network was determined based on the percentages of acquired information and relying on the spatio-temporal Kriging. Based on UK and KwET, electrical conductivity (EC) was the best covariate. KwET with EC as a covariate was the superior Kriging method. A network covering 111 wells showed to be as informative as the existing monitoring network with a total of 237 wells.
A. Hassanoghli
Abstract
Produced sludge from wastewater treatment plants is a source of macro and micro nutrients and organic matters which is needed for agriculture. On the other hand, application of sludge with no criterion may cause some health risks and also, soil and surface water and ground water resources pollution may ...
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Produced sludge from wastewater treatment plants is a source of macro and micro nutrients and organic matters which is needed for agriculture. On the other hand, application of sludge with no criterion may cause some health risks and also, soil and surface water and ground water resources pollution may be followed. In this regards, the effect of different amounts of sewage sludge used as organic fertilizer in compare with chemical fertilizers on transport of minerals below the root zone and yield and yield components in soybean cultivation were studied. Therefore, 15 cylindrical plastic soil culomns with a height of 100 cm and 60 cm diameter were constructed and drainage PVC pipes with geotextile filter were installed for all of them. The sludge of Ekbatan housing complex wastewater treatment plant after processing and digestion was taken place and used. The culomns were filled by a Clay Loam textured soil and Soybean (Williams variety) was planted. Treatments include three levels of wastewater sludge fertilizer (10, 25 and 50 ton/ha), chemical fertilizers (150 kg/ha ammonium phosphate and 50 kg/ha urea) and control without using fertilizer in three replications. According to the results, the highest mean amount of nitrate in drainage water of culomns (base on split plot through time as statistical completely randomized design) was 57.17 mg/lit in the early season and treatment related to the use of sludge was 50 ton/ha. The lowest mean value of nitrate obtained from the control in the end of cultivation season and was 3.51 mg/lit. The most yield of Soybean was 277.85 gr grains per culomn which obtained from use of 50 ton/ha of manure sludge. The greatest weight of 1000 grains and the number of pods with values of 127.42 gr and 856 in number, measured in this treatment too. Application of 25 ton/ha sludge, chemical fertilizers and 10 ton/ha sludge were after it, respectively. So, the highest use of sewage sludge on soybean cultivation (at the rate of 50 ton/ha), transfer the highest amount of nitrate below the root zone and led to the best yield indicators
A. Mohseni; H. Mirseyed Hosseini; F. Abbasi
Abstract
Fertilizing method plays an important role in fertilizer and water use efficiency and plant yield and losses fertilizer. A field experiment was carried out at 16 treatments with factorial a complete randomized block design during 2010 for free drainage furrows. First factor was four levels of water (60, ...
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Fertilizing method plays an important role in fertilizer and water use efficiency and plant yield and losses fertilizer. A field experiment was carried out at 16 treatments with factorial a complete randomized block design during 2010 for free drainage furrows. First factor was four levels of water (60, 80, 100 and 120% of full irrigation) and second factor was four levels of fertilizer (0, 60, 80 and 100% of required fertilizer) for fertigation method. The 16 treatments mentioned above, were compared with common fertilizing method. Nitrogen requirement was applied in four stages of the growth: before cultivation, in seven leaves, shooting and earring stages, the first portion (before cultivation) was applied by manual distribution and others by fertigation. In conventional treatment, the whole of required fertilizer was used in two split applications (before planting and in seven leaves). Results showed, the highest yield, yield component and use efficiency of corn was obtained on 100% irrigation and 100% fertilizer treatments. While the highest amount percolation of nitrate into soil was related to conventional treatment.
