Soil science
R. Motalebifard
Abstract
Introduction
Grape is one of the most important horticultural products in the world and Iran which has been noticed due to its cultivation area, high economic and nutritional values. Annually, about 68 million tons of grape are produced in the world. Iran, with 309,000 ha cultivation area and ...
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Introduction
Grape is one of the most important horticultural products in the world and Iran which has been noticed due to its cultivation area, high economic and nutritional values. Annually, about 68 million tons of grape are produced in the world. Iran, with 309,000 ha cultivation area and about 3.3 million tons share of production, is the 11th largest producer of this fruit in the world. Recent studies have shown that plant nutrition and soil fertility have significant effect in the reduced yield quality in the grape fields of our country. Plant nutrition as an influential factor is a function of the interaction of nutrients and environmental conditions. Assessing the nutritional status of plants is necessary to achieve the relationship between nutrients availability in the soil, the amount of elements in the plant and yield. Plant analysis method is used to optimize fertilizer application and diagnose plant nutrition disorders. The plant analysis method is useful for evaluating plant nutrition if an appropriate method to be used to diagnose and interpret the results. Tissue nutrient status can be diagnosed by the Critical Value Approach (CVA), the Diagnosis and Recommendation Integrated System (DRIS), and Compositional Nutrient Diagnosis (CND). Only DRIS and CND provide nutrient imbalance indexes, although no threshold value has been validated yet for diagnostic purposes. CND method expresses interactions by considering the ratio of one element to all elements. In this method, high and low functional groups are separated with great accuracy with the help of mathematical and statistical methods and the application of the cumulative function of variance ratio of nutrients and chi-square distribution function. A critical CND imbalance index was derived from the chi-square distribution function. Due to the importance of grape production in the country and the lack of required nutritional norms, this study was conducted to investigate the nutritional status of grape fields using the CND method.
Materials and Methods
In order to evaluate the nutritional status of grape fields in the Hamedan province, this study was conducted in the cropping years of 2017-2020. Every year, 40 different orchards were selected in each of the regions. The orchards were selected in such a way that they had different ranges of yield and soil properties. A database containing laboratory and field data was created for each grape field. The geographical location was recorded for the orchards. In each orchard, plant (leaf) samples were prepared and analyzed based on suitable laboratory methods. At the end of the season, the yield and its components were determined by visiting each orchard. Concentrations of nitrogen, phosphorus, potassium, calcium, magnesium, iron, zinc, manganese, and copper were measured in grape leaves. The project database was completed and CND indices were calculated for each nutrient element. The selected grape fields were divided into two groups with high and low yield based on yield. The CND norms and indexes were computed according to computation steps of Parent and Dafir. The Cate–Nelson ANOVA procedure was used to partition yield data between two groups by maximizing the between-groups sums of squares to determine the threshold values for CND indexes required to compute the critical CND r2 value. We used 83 observations for developing the nutrient norms.
Results and Discussion
The results of the indices calculated by the method of CND showed that the grape fields were deficient in nitrogen and potassium among the macronutrients and iron and manganese among the micronutrient elements. There was a correlation (0.25) between nutritional balance index and yield that was significant at 1 percent probability level. Potassium index was negative in 83% of low yield orchards. After potassium, nitrogen had a negative index in 58% of medium and low yield orchards. Phosphorus had the most positive index among macronutrients and was positive in most orchards. Among the micronutrients, manganese, iron, and zinc indices were negative in 59%, 49% and 73% of the orchards, respectively. The presence of calcareous conditions in the soils of the region can be the reason for this deficiency. The boron index was positive in some orchards and negative in some other orchards. Furthermore, in total, the index of unknown factors was negative in 41% of grape fields in Hamadan province.
Conclusion
The results indicated that management of evaluated orchards was not suitable and application of chemical fertilizers was unbalanced. The results of this study can be used in grape fields to increase yield and product quality. Therefore, it is recommended to use deficient elements in the fertilization program to improve yield.
rahim motalebifard
Abstract
Introduction: 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. In Iran this important crop has third rank after wheat and tomatoes with the production of 4.6 million tons. Potato is a temperate crop, growing ...
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Introduction: 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. In Iran this important crop has third rank after wheat and tomatoes with the production of 4.6 million tons. Potato is a temperate crop, growing and yielding well in cool and humid climates or seasons, but it is also cultivated in tropical to sub-polar climatic regions, and represents a major food crop in many countries. Potato is sensitive to nutrients deficiency especially phosphorus and zinc. At least one-third of the cultivated soils globally are estimated to contain too low amounts of bioavailable zinc for optimal crop production. In Iran more than 70 percent of irrigated soils suffer from zinc deficiency. Many reasons have role in mentioned deficiency such as calcareous and alkaline soils, lower organic carbon and higher application of phosphorus fertilizer. So, evaluation of zinc fertilizers efficiency is essential under different soil phosphorus conditions.
Materials and Methods: This project was carried out in order to investigate the effect of zinc sulfate levels on yield, nutrients concentration and zinc recovery and agronomic efficiency under different phosphorus conditions in potato (Solanum tuberosum L.) in Hamedan province (Tajarak station). The current research was done as a randomized complete block design with 9 treatments, three replications and three locations (with different soil phosphorus levels). The phosphorus locations were involved two locations with 10-15 mg available P per kg of soil (without or with phosphorus application) and a locations with 20-25 mg available P per kg of soil. Zinc treatments were consisted of soil application of 0, 20, 40, 60, 80, 100 and120 kg of zinc sulfate (ZnSO4.7H2O) per hectare and foliar spray of zinc sulfate at the rate of 5 grams per liter at one week before and one week after flowering. After harvesting, the tuber and shoot yield, tubers and shoot zinc uptake, nutrients concentration were measured in different parts of potato plant, and recovery and agronomic efficiency of applied zinc fertilizer were calculated.
Results and Discussion: The results showed that the zinc treatments significantly affected the tuber yield of potato. The application of 40 kg.ha-1 zinc sulfate and foliar spray of Zn one week after flowering evidenced the highest and the lowest yield, respectively and the difference between these treatments were 17 percent. The differences between without Zn application and foliar spray of Zn one week after flowering were not significant on yield which showed that the time of fertilizer foliar application is very important and by delaying of foliar spray the yield could not increase. The zinc treatments affected significantly tuber zinc uptake and the foliar spray of Zn one week after flowering by 80 percent increase comparing with control, had the highest tubers zinc uptake. The tuber and shoot zinc concentration were significantly affected by the zinc sulfate levels. The highest and lowest concentration of zinc in shoot and tubers were observed in the foliar spray of Zn one week after flowering and control. This treatment caused 160 and 24 percent increasing in shoot and tubers zinc concentration in comparison with control. In spite of considered increase in zinc content by foliar application of zinc one week after flowering, the potato yield did not increase considerably. The tuber and shoot yield were affected significantly by different phosphorus locations (p
rahim motalebifard
Abstract
Introduction: With 12 million tons production per year, garlic is the fourth important crop in world. In addition to its medical value, it has been used in food industry. The Hamedan province with 1900 ha cultivation area and 38 percent of production is one of the most important garlic area productions ...
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Introduction: With 12 million tons production per year, garlic is the fourth important crop in world. In addition to its medical value, it has been used in food industry. The Hamedan province with 1900 ha cultivation area and 38 percent of production is one of the most important garlic area productions in Iran. Few studies on water use and management of garlic exist in the world. Garlic is very sensitive to water deficit especially in tubers initiation and ripening periods. The current research was done because of scarce research on garlic production under water deficit condition in Iran and importance of plant nutrition and nutrients especially nitrogen on garlic production under stressful conditions. Nitrogen is necessary and important element for increasing the yield and quality of garlic. Application of nitrogen increases the growth trend of garlic such as number of leaves, leaf length and plant body. Reports have shown that garlic has high nitrogen requirement, particularly in the early stages of growth.
Materials and Methods: This study was conducted for evaluating the combined effects of nitrogen and irrigation on the yield and quality of garlic (Allium sativumL.). The study was performed as a split-block based on randomized complete blocks design with factors of irrigation at four levels (0-3(normal irrigation), 3-6 (slight water deficit), 6-9 (moderate water deficit) and 9-12 (sever water deficit) meters distance from main line source sprinkler system), nitrogen at four levels (0, 50,100 and 150 kg nitrogen per ha) using three replications and line source sprinkler irrigation system. The total water of irrigation levels was measured by boxes that were fixed in meddle of each plot. The statistical analysis of results were performed using themethod described by Hanks (1980). The chlorophyll index was measured using the chlorophyll meter 502 (Minolta, Spain). The chlorophyll a and bwas measured by the method described by Arnon (1946) and Gross (1991) in fresh leaf samples using spectrophotometer at 645 and 663 nm. Data were subjected to analysis of variance using MSTATC and SPSS softwares. Duncan’s multiple range test at p≤0.05 probability level was applied to compare the mean values of measured attributes. The Excel software (Excel software 2007, Microsoft Inc., WA, USA) was used to draw Figures.
Results and Discussion: The results showed that, the application of nitrogen significantly affected most of measured attributes. The application of 150 kg N per ha showed highest stem height (40.5 cm), dry weight of stem (5.34 g),wet weight of stem (69.5 g), chlorophyll index (49.7),chlorophyll a (9.8 mg.g-1dw) and chlorophyll b (4.04 mg.g-1dw) and increased stem height, dry and wet weight of stem, chlorophyll index and chlorophyll a and b around 7, 6, 7, 12, 22 and 36 percent, respectively. The irrigation levels significantly affected most of measured attributes similar to the nitrogen levels. The application of 409 mm irrigation water per growing season resulted to maximum stem height (41.9 cm), leaf number (7.5), dry weight of stem (5.39 g) and wet weight of stem (70.1 g), chlorophyll index (50.5) and chlorophyll a (10.2 mg.g-1dw) and chlorophyll b (4.04 mg.g-1dw). The severe water deficit (application of 138 mm irrigation water per growing season) decreased stem height, leaf numbers, dry and wet weight of stem, chlorophyll index and chlorophyll a and b about 13, 36, 12, 12, 19, 42 and 44 percent, respectively. The two way interaction of nitrogen and irrigation was significant and mostly synergistic on wet and dry weight of stem. The highest amounts of stem wet weight (73.2 g) and stem dry weight (5.63 g) were resulted from application of 150 kg nitrogen per ha under full irrigated condition that increased dry and wet weight of stem 17 and 25 percent respectively comparing with without nitrogen application under sever water deficit condition. Application of 409 mm irrigation and 100 kg N per ha is suitable for condition that enough irrigation waterexists. However in water deficit condition, the application of 150 kg nitrogen per ha could be recommended.
Conclusion: In general, to achieve the optimum growth of garlic in similar soils and climatic conditions, application of 100 kg nitrogen per ha would be recommended under normal irrigation conditions while at water deficit conditions the application150 kg nitrogen per ha could be recommended that had only two percent difference with the mentioned treatment and this difference was not significant.
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
H. Besharati; R. Motalebifard
Abstract
Introduction: After soybean and palm oil, canola is third important oil seed in the world which belongs to the genus Brassicaceae, that its seeds contain about 40% oil. The per capita consumption of oil in Iran is about 14 kg, so approximately 900 thousand tons of oil will be required for each year. ...
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Introduction: After soybean and palm oil, canola is third important oil seed in the world which belongs to the genus Brassicaceae, that its seeds contain about 40% oil. The per capita consumption of oil in Iran is about 14 kg, so approximately 900 thousand tons of oil will be required for each year. However, only less than 10% of this oil is produced in the country. In recent years, special attention has been paid to canola cultivation in order to increase oil production, so during recent years an apparent increase in canola cultivated lands is significant. In most of these canola cultivated lands, the soil is calcareous therefore; some available nutrients such as phosphorus, iron and zinc are less than the amounts required by plants. Increasing qualitative and quantitative yield of canola in calcareous soils is a priority to canola cultivation improvement. Sulfur plays an important role in oil content of oily seed crops. On the other hands sulfur oxidation in calcareous soils can improve some nutrients availability. The present study was designed to investigate the effect of sulfur on yield, oil content and nutrients uptake and also its impact on soil chemical properties with 8 treatments, in 3 replications.
Materials and Methods: This study was conducted in Ekbatan research station in Hamedan province for 2 years as completely randomized block design with 8 treatments and 3 repetitions. The treatments were: T1: Control (Without sulfur and Thiobacillus), T2: Application of 150 kg sulfur per ha, T3: T2+ Thiobacillus inoculums (2% of applied sulfur), T4: Application of 300 kg sulfur per ha, T5: T4+ Thiobacillus inoculums (2% of applied sulfur), T6: Application of 600 kg sulfur per ha, T7: T6+ Thiobacillus inoculums (2% of applied sulfur) T8: Fertilizing based on soil test without sulfur and Thiobacillus. Thiobacillus inoculant containing about 107 cells of Thiobacillus bacteria which belonged to neutrophile Thiobacilli were prepared at soil biology Dep. of Soil and Water Research Institute. In this research treatments were applied in two separate sites (each site contains 24 plots which their dimensions were 2.4×10 meter). For evaluating the residual effect of treatments, the experiment was carried out in constant plots in second year. Phosphorus, iron, zinc, manganese and sulfate, were not applied to any of the treatments except for T8, and the above mentioned treatments were just received 250 kg urea. These all treatments were applied only in the first year and on the second year of experiment their Residual effects on canola were evaluated. During the growing season agricultural practices such as irrigation, weed and pest control in all units were managed uniformly. Soil chemical data were obtained by analyzing of Ec, pH and bicarbonate each year in May. The leaf and seed samples were taken for essential analysis. When plants growth completed, each plot was harvested separately then canola yield and also the phosphorus, iron and zinc content of shoots and grain were measured.
Results: The results of two years indicated that the treatments had no significant effects on pH and bicarbonate of soil while increasing sulfur application rate, caused a decrease in soil bicarbonate content. In addition to that, the treatments did not affect the yield of canola significantly. In the first year of experiment, treatments had shown significant effects (P=0.01) on glucosinolates, seed sulfur and Cu of leaf, whereas no effect determination was occurred about indices of leaf and seed of canola. the results also suggested an increase of 800 kg in the sixth treatment (600 kg sulfur consumption without Thiobacillus) and canola seed yield of treatment T6 enhancedfrom 3446 kg to 4531 kg per ha. Fertilization treatment (T8) could not increase canola yield, so it confirms that the nutrient concentration in experiment sites were near the critical level for canola.
Conclusion: In total results revealed that different sulfur treatments have no significant and considerable impacts on canola yield and soil chemical properties, and the effects was not observed in the second year of experiment, too. Probably the sulfur consumed or sulfur oxidation in the experiments was not enough to cope with high lime (14%) and buffering capacity of the soil. Also probably the nutrient concentration in test sites were more than critical level for canola and plants absorbed enough nutrients from the soil. No increase in canola yield in fertilization treatments (T8) can confirm this opinion, though. It also seems that there were no favorable conditions (soil moisture) for the oxidation of sulfur in the soil.
