فهرست مطالب mehri sharif

This study was conducted to evaluate the relationship between leaf iron and some easily-available soil properties in citrus orchards in the southern region of Kerman province by artificial neural network modeling and stepwise regression. For this purpose, 40 orchards were selected from the study area and the physical and chemical properties of soil and iron in the plant leaves were measured. Using artificial neural network in different models with different data from soil properties as input and leaf iron as output, the ability of these models to predict leaf iron concentration was evaluated. The results showed artificial neural network with variables of organic carbon, pH, clay, phosphorus, TNV and electrical conductivity with explanation coefficient of 0.86 and 0.81 and root mean square error (RMSE) of 14.60 and 20.13 mg.kg-1 for data Training and testing were the best models in estimating leaf iron. Comparison of regression and neural network models in the test data showed that the neural network had a higher accuracy with an explanation coefficient of 0.81 than stepwise regression with an explanation coefficient of 0.2. The amount of RMSE in the neural network also improved and increased from 27.72 mg.kg-1 in the stepwise regression model to 20.13 mg.kg-1 in the neural network. Artificial neural networks have been able to predict the iron in plant leaves based on the easily-available properties of the soil, so that by choosing organic carbon as the input of the first model to the best model by selecting organic carbon, pH, clay, phosphorus, TNV and electrical conductivity, model accuracy increased.

Due to the fact that it is not possible to remove chemical fertilizers in agriculture at once and also the use of organic fertilizers alone cannot fully complete the nutritional needs of plants, especially annuals plants, so the use of organic fertilizers with optimal use of Chemical fertilizers can play an important role in maintaining the physical and chemical structure of soil, increasing crop yield and reducing the negative environmental effects of chemical fertilizers. In the southern region of Kerman province, potatoes have been cultivated in autumn and winter for more than a decade. According to the studies on the amount and type of fertilizers used in autumn cultivation in the region, it seems that there is excessive consumption of fertilizers, especially urea, which, while producing a problematic crop, has destroyed soil fertility and polluted groundwater. One of the effective actions to reduce or stop this wrong process is the optimal use of chemical fertilizers and the use of organic fertilizers. This study was conducted to evaluate the application of poultry manure and urea fertilizer in potato production in the south of Kerman province.

The experiment was conducted in a randomized complete block design with five treatments, in three replications and for two years in Jiroft. The research treatments were: 1- Control (as in the region), 2- Recommended optimal urea limit for the region crop + Optimal consumption of other nutrients based on soil test, 3- Urea consumption 25% more than the optimal limit + Optimal consumption of other nutrients based on soil test, 4- Consumption of urea 25% less than the optimal limit + five tons of poultry manure per hectare + optimal consumption of other nutrients based on soil test and 5- Consumption of urea 25% less than the optimal limit + ten tons of poultry manure per hectare + Optimal consumption of other nutrients based on soil test. At the end of each year, the performance of each treatment was measured. Also, random samples were prepared from the tubers and leaves of each plot and potassium, iron, zinc, manganese and nitrate were measured in the tubers and leaves.

The results showed that the control treatment had the lowest yield (20 t / ha) and the highest nitrate concentration (293.3 and 639.5 mg/kg dry matter, respectively) and the lowest concentrations of potassium, iron, zinc and manganese in tubers and leaves. While treatment number five had the highest yield, which shows an increase of 74% compared to the control. Treatment number four had the lowest amount of nitrate, which had 48.8%, 14.6, 32.3 and 13.8% less nitrate in the tuber than treatments one, two, three and five, respectively.

The results showed that the application of treatment number five caused the production of about 35 tons per hectare and reduced the concentration of nitrate in the tuber (30% less than the critical level in Iran). Also, in terms of economic importance, the application of the recommended treatment, while reducing the consumption of urea fertilizer by 50% and increasing production by 75%, resulted in an income of about 50% more than the control treatment.

The southern region of Kerman province with the production of citrus about 500 thousand tons per year, is ranked third in the country. One of the limiting factors of citrus production in this region in terms of quantity and quality is the concentration of some elements, especially boron in irrigation water. The effect of organic fertilizer, superabsorbent and chemical fertilizer with calcium on reducing the boron toxicity of irrigation water on sure orange rootstock in a factorial experiment was conducted in a randomized complete block design with 4 replications in 1996 and 1997. The factors include cow manure at two levels (0 and 2wt%), superabsorbent with three levels (0, 0.1 and 0.25wt%) and chemical fertilizers at three-level (control, balanced application chemical fertilizers without calcium based on soil test and balanced application of chemical fertilizers with calcium from calcium nitrate source based on soil test). The irrigation was done by drip irrigation with water with EC 845 μs / cm and boron concentration of 1.55 mg / l. The results showed that the simple and combined effects of superabsorbent, chemical and organic fertilizers on the percentage of leaves with boron toxicity symptoms, boron concentration was significant at the level of one percent. The highest concentration of boron per leaf (144.3 mg / kg) was observed in the control treatment with the highest number of leaves with symptoms of boron toxicity (22.97%) and the lowest concentration of potassium, magnesium, iron and zinc. Combined use of 2% organic matter + 0.25% superabsorbent + balanced use of chemical fertilizers based on soil test (without calcium) had the lowest percentage of leaves with symptoms of boron toxicity and the lowest amount of boron, but the highest percentage of magnesium increase (136.4) Showed potassium (197.4), iron (139) and zinc (123) compared to the control treatment. The results showed that separate and combined application of chemical and organic fertilizers with superabsorbent in soils with boron toxicity can reduce the effects of toxicity and improve plant nutritional conditions.

This study was conducted to evaluate the application of growth stimulants and chemical fertilizers on yield of Valencia oranges in the south of Kerman province. 

The experiment was performed as a factorial experiment in a randomized complete block design with 21 treatments in three replications. The first factor was chemical fertilizer at three levels and the second factor was growth stimulants at 7 levels. At the end of the experiment, yield, weight and average diameter of fruit and total soluble solids, total acidity, pH and vitamin C in fruit were measured. 

Seaweed showed the greatest effect on fruit diameter and yield, which were 2.9 and 53.3% better than the control, respectively. In chemical fertilizer treatment based on 75% of soil test, humic acid had increased yield (22.6% of a control treatment). Also, regardless of the type of chemical fertilizer treatment, the highest amount of nitrogen, phosphorus and potassium was observed in the seaweed treatment. 

Humic acid and seaweed were the best growth stimulants in increasing yield in the presence or absence of chemical fertilizers. The treatment of Chemical fertilizer based on soil test and foliar application of seaweed with a concentration of 5 per thousand after falling flowers and Hazelnut fruit showed the highest increase in the yield and nutrient uptake in leaves compared to other treatments.

This study was conducted to evaluate the application of poultry manure and urea fertilizer in onion in the randomized complete block design with three replications during 2018 and 2019. The treatments were:1-Control (276 kg/haN), 2-Recommended optimal nitrogen limit for the region crop (184 kg/haN)+Optimal consumption of other nutrients, 3- nitrogen consumption 25% more than the optimal limit+Optimal consumption of other nutrients, 4-Consumption of nitrogen 25% less than the optimal limit+five t/ha of poultry manure+optimal consumption of other nutrients and 5-Consumption of nitrogen 25% less than the optimal limit+tent/ha of poultry manure+Optimal consumption of other nutrients. The results showed that the effects of treatments on yield, the concentration of other elements, and nitrate residuals in onion bulbs and leaves were significant at the level of 1% probability. The control had the lowest yield (43.3t/ha) and the highest nitrate residuals (184.3 and 571.2mg/kg, respectively) and the lowest concentrations of potassium, iron, zinc, and manganese in bulbs and leaves. Also, treatment five showed the highest yield (25.1% increase compared to the control), and no significant difference in yield was observed between treatments four and five. The lowest nitrate residuals in bulbs were in treatment four, which was 69.9%, 21.7, 43.3, and 3.4% less than treatments one, two, three, and five, respectively. The application of treatment four, while reducing the consumption of urea fertilizer by 50% and as a result of reducing nitrate in bulbs to less than the critical level and increasing the yield by 18%, resulting in about 11% more revenue than the control.

In order to investigate the effect of organic matter, superabsorbent and optimum nutrition on reducing the effect of salinity on irrigation water on sure orange rootstock, a factorial experiment was conducted in a randomized complete block design with 12 treatments and 4 replications. the first factor was an organic matter with two levels (0 and 2 wt%), the second factor was superabsorbent with three levels (0, 0.1 and 0.25 wt%) and the third factor was the two-level optimum nutrition (no fertilizer and optimum fertilizer of required by the plant-based on soil testing. Leaves percentage with symptoms of salinity damage and concentrations of zinc, iron, boron, phosphorus, potassium, sodium, calcium and magnesium were measured different treatments. The results showed that the combined application of animal manure with a superabsorbent fertilizer resulted in an increase in the concentration of these elements in the shoot compared to the control. The highest percentage of sodium (0.17) and leaves with salinity (22.01) and the highest amount of boron (148.2 mg / kg) were observed in control treatment. Also, C2D3E2 treatment (combined 2% organic matter, 0.25% superabsorbent and optimum nutrient intake) had the lowest sodium content and leaves with salinity and lowest boron content, but the highest increase in potassium, iron and zinc with about 2% Equal to their values in the control treatment