JWSS - Journal of Water and Soil Science

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The inhibitory effects of thyme and ajowan oils on growth of A. parasiticus on pear during cold storage were studied. The main components of the two essential oils are phenolic compounds such as thymol and carvacrol with antimicrobial properties. Pear samples were inoculated by suspension ( 10⁶ spor/ml) of A. parasitcus spores and sprayed by thyme (200 p.p.m) and ajowan (300p.p.m) separately and kept in cold storage (0 ±1⁰C and relative humidity of 85%). Organoleptic test for evaluating oil odor residue was studied after 3 months. The amount of spoilage and contamination of pear fruit in 1^st, 2^nd, and 3^nd month after cold storage was determined and were data the statistically analyzed. The results showed that in spite of the higher thymol content in ajowan oil constituent, which is well known as an antimicrobial agent Stronger than thyme oil, thyme oil at 200 p.p.m was more effective than ajowan oil in controlling and preventing, A.parasiticus growth in pear. It seems this is due to synergistic effects of other phenolic compounds such as carvacrol which does not exist in ajowan oil. The results of organoleptic test showed that the samples treated with ajowan oil have more acceptance than those treated with thyme oil thie applied even to the control sample. According to the results, thyme and ajowan oils are good promising natural antifungal agents without any hazardous effects on human health and can be successfully use as chemical fungicides.

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To obtain soil-moisture characteristic curve experimentally is time-consuming and usually subject to considerable errors. So, many investigators have tried to predict soil-moisture characteristic curve by different models. One of these models predicts soil moisture characteristic curve based on soil particle size distribution and bulk density. In this model, soil particle size distribution curve is divided into a number of segments, each with a specific particle radius and cumulative particle mass greater than that of the radius. Using these data, soil-moisture characteristic curve was estimated. In this model, a scale factor, α, is used which may be considered as a constant, or obtained by logistic or linear procedures. The average values of α for clay, silty clay, sandy loam, two loam soils, and two silty clay loam soils were 1.159, 1.229, 1.494, 1.391, 1.393, 1.253 and 1.254, respectively. For most conditions, soil particle size distribution curve is not available, but only the percentages of clay, silt, and sand could be obtained using soil textural data, which is not enough to draw a precise soil particle size distribution curve. In this situation, a precise soil particle size distribution curve must be initially developed on the basis of which the soil moisture characteristic curve can be predicted. In this study, using soil textural data of seven different soils, soil moisture characteristic curve of each was estimated. In these estimations, logistic and linear methods were used to obtain the α value. Then, the results were compared with those of measured soil moisture characteristic curve. For estimation of soil particle size distribution curve, two extreme values for soil particle radius, 125 and 999 m, were used. The results indicated that using particle radius of 999 µm is more appropriate. On the other hand, it was found that for clay, silty clay, and sitly clay loam texture, it is more appropriate to employ a linear equation to determine for estimating soil-moisture characteristic curve while the logistic equation can be more appropriately used for loam and sand loam textures.

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In a completely randomized design, the effects of six different additive compounds including limestone, hydrochloric acid, zeolite, aluminum sulfate, pad ammoniac, and fatty acids on nitrogen, pH, temperature, moisture, water soluble phosphorus, and microbial count of litter of broiler chicken were investigated. Each compound was added at a level of one kg/m² of litter. Six–hundred-and-sixteen (616) day- old broiler chickens (both sexes) were divided into 28 groups, 22 chicks per group. Four replications were allocated to each treatment from 1 to 56 days. All groups were fed with the same diet. Litter moisture was not affected by the treatment. Experimental treatments significantly (p<0.05) influenced the litter pH on day 21. The lowest pH was obtained with aluminum sulfate and the highest pH was obtained with limestone. At the end of the experimental period, all treatments had nearly the same pH levels. Litter temperature was not affected by the treatments . Experimental treatments had a significant (p<0.05) effect on litter nitrogen and bacterial count. Correlation between litter pH and nitrogen was significant and negative (r = -0.95, p<0.05). Effect of treatments on soluble P was significant and the lowest soluble P belonged to aluminum sulfate and pad ammoniac. Correlation between soluble P and pH was positive (r = 0.48, p<0.05). The results showed that some chemical compounds can be used to reduce litter pH, nitrogen, and soluble P and their effectiveness diminishes as chicks grow older.

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This experiment was conducted to evaluate the effects of adding acetic acid to drinking water on the performance and ileal microorganisms of broiler chickens. In a completely randomized design with 5 treatments and 5 replicates, 300 day-old commercial mail broiler chicks (ROSS) were divided into 25 groups, 12 chicks per group. Each of the five levels of acetic acid added to drinking water (0.0, 0.1, 0.2, 0.3, and 0.4%) were given to five replicates for a period of 21 days. All groups were fed a practical corn-soybean based diet. During the experiment, chickens were not fed any antibiotics or coccidiostats. The diet formulation for all groups was the same. At 14 and 28 days of age, one chicken of each replicate was weighed and killed by cervical dislocation. Ileal contents were collected and used for microbial evaluation. At 49 days of age, one bird from each pen was killed to weigh gastrointestinal tract, liver, pancreas and abdominal fat. The number of total aerobes and colliforms per gram of ileal contents were enumerated on the appropriate bacteriological media. There was no significant difference in feed intake, weight gain, feed to gain ratio, live body weight, gastrointestinal tract, abdominal fat, liver and pancreas weights (p>0.05). Also, the differences among treatments for total aerobe and coliform counts were not significant (p>0.05). Under the conditions of this study, addition of acetic acid as an organic acid into drinking water at the levels used could not affect the performance and ileal microbial counts of chickens.

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Lintz-Donawitz (LD) converter slag, a by-product of the iron and steel-making industry is produced in large quantities in Isfahan, Iran. The slag contains 52.8 and 2.2% (w/w) CaO and MgO, respectively. To determine the influence of LD slag on the chemical characteristics of three acid soils from Gilan, an incubation study was conducted. The soil samples were collected from 0-30 cm of rice and tobacco fields and a tea garden. Treatments were 0, 0.5, 1, 2, 4, 8 and 16 % (w/w) of converter slag/kg soil. The slag was thoroughly mixed with 500g soil in plastic pots. Soil moisture content was adjusted to near field capacity and changes in pH, EC and AB-DTPA-extractable Fe, Mn, Zn, P and K were determined at 1, 10, 30 and 60 days. Results showed that soil pH increased with increasing slag rates. Slag increased AB-DTPA-extractable P and Mn, the magnitude increase depend on the amount of slag applied. However, the effect of slag on AB-DTPA-extractable Fe depended on initial pH, initially decreasing at the pH range of 7.4 - 8.5 and then increasing at higher pH levels. Slag decreased AB-DTPA-extractable K especially in highly acid soil. In the present study, soil pH and AB-DTPA-extractable Fe decreased with time, though the effect of incubation time on pH was not significant. The effect of incubation time on AB-DTPA extractable Mn and P was different. Time effect on EC and AB-DTPA-extractable K was not significant. In general, soil chemical characteristics were more affected by slag rates than by incubation time. In conclusion, it seems that converter slag is a suitable amendment for acid soils. It is suggested that the effect of LD converter slag on plant growth and chemical characteristics of acid soils be studied under field conditions.

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Two hundred Arian broiler chicks were used to investigate the effect of contents of dietary glucosinolates on performance of broiler chicks during starter (0-21 days of age) and grower periods (22-42 days of age) in a completely randomized design. The dietary glucosinolates contents in the starter period were 0 (S₁), 7.5 (S₂), 15 (S₃), 22.5 (S₄), 30 (S₅) µmol/g and in the grower period they were 0 (G₁), 5.7 (G₂), 11.4 (G₃), 17.1 (G₄), 22.8 (G₅) µmol/g. Feed intake during the grower period was affected (P<0.05) by different levels of glucosinolates in the diets and the lowest feed intake was observed in the G₅ treatment. The lowest body weight gains were observed in the S₅ and G₅ treatments during the starter and grower periods, respectively (P<0.05). The feed conversion ratio (FCR) in the S₅ treatment for the starter and the G₅ treatment for the grower period were significantly different (P<0.05) from other treatments. The correlation between the body weight gain and level of dietary glucosinolates or glucosinolate consumption was high during the starter (r = -95.3% and -94.7%, respectively) and relatively high (r = -69.5% and -72.4%, respectively) during the grower period. This experiment showed that the amount of glucosinolates in the diets of broiler chicks for the periods of starter and grower feeding system should not be more than 11.36 and 8.11µmol/g diet, respectively. Also during the starter and grower feeding periods, the highest level of rapeseed meal could be used in the broiler diets are 13 and 8 percent, respectively.

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Of all types of xenobiotics, pesticides such as herbicides play a significant role in soil and water pollution due to their widely usage all over the world. This study addresses the ability of organic amendments to enhance atrazine and metamitron degradation in two herbicide contaminated soils with contrasting textures under laboratory conditions. Soil samples were collected from surface soils with textures of sandy loam and silty clay, from northeastern part of Iran. Initial concentration of herbicides was 50 mgkg^-1 soil. Contaminated soil samples were treated by manure, compost and vermicompost at the rates of %0.5 and %2 (w/w). Residual concentrations of atrazine and metamitron were determined by HPLC at the end of incubation periods of 20,40 and 60 d. Residual concentrations of atrazine were 93, 77.8 and 72.4 % of the initial concentration after 20, 40 and 60d incubation, respectively. Residual metamitron concentrations were clearly lower than atrazine. After 20,40 and 60 d., the remaining concentrations of metamitron were 5.8, 2 and 1.2 %, respectively. Organic amendments at the rates of .5 and 2 % showed similar effects on the enhancement of herbicides degradation in soils. However, no significant effect was observed between types of organic amendments. Degradation was clearly affected by soil textures. Residual concentrations of herbicides were higher in sandy loam than in silty clay soil.

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Increasing soil contamination by chemicals has become an issue of increasing environmental concern. Leaching of chemicals into and through the vadose zone creats serious problems due to the contamination of the soil matrix, soil solution and groundwater. Therefore, in order to study the effect of the preferential flow, macropores and organic matter on mobility and leaching of the metals such as cadmium lead, and zinc, an experiment was conducted as a factorial-split plot based on the completely randomized design with three replications. Three treatments of the undisturbed soil (U), the disturbed soil (D) and the disturbed soil containing 3 percent organic matter (O) were leached by the solutions with the concentration of 20 mg.L^-1 of Cd, Pb, and Zn for a month. Then the concentrations of Cd, Pb and Zn in the leachate were measured at different time intervals. The ANOVA results indicated that the metals had a significant difference in the leachate at 1% and the order of their mobility was: Zn>Pb>Cd. Also, there was a significant difference between different soil treatments at 1% and the concentration of the three metals in U and O treatments was more than their concentrations in D treatment. Furthermore, a significant difference between the time intervals of leaching (pore volumes) was observed at 1%. So that, Cd in leachate of U, O and D treatments indicated a significant difference after leaching for 3, 3 and 5 days, respectively (1%). But, Pb in the leachate of the three soil treatments after leaching for 11 days had a significant difference. Zn concentration only in O treatment had a clear trend at different time intervals of leaching and a significant difference was observed after leaching for 8 days.

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An experiment was conducted to study the effects of substitution of the different levels (0.0, 10, 20, 30 and 40%) of oat grains for the corn with and without enzyme supplementation (β -Glucanase. 0.0 and 1%) on the performance of the broiler chickens. Four hundred and eighty (480) Arian broiler chicks were employed in a randomized complete block design with 10 treatments and 3 replications (16 chickens for each replicate) from 1-56 days of age. The chicks fed with 10 percent of oats in the diets, supplemented with enzyme, had significantly higher BW than other treatments. While with 40 % oat in diet body weight were significantly decreased. The feed conversion increased with increasing of the oats levels and the enzyme supplementation resulted in lower feed conversion. With increasing oats in the diet, the percentage of carcass weight decreased, but the pancreas weight increased significantly. Conversely, the enzyme supplementation resulted an increase in carcass weight and reduction in the pancreas weight. The percentage of the tibial ash, calcium and phosphorus were unsignificaulty decreased with the increasing of the oat but enzyme lementation resulted an increase in tibial ash, calcium and phosphorus. In the areas where the corn production is limited, including 30 percent of the oats supplemented with enzyme in the diet of the broiler chicks can be beneficial.

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Some of the field crops are severely affected by the Fusarium foot and root-rot in the west of Iran, Hamadan. Pathogenic Fusarium species are potentially severe destructive diseases and could be a major limiting factor for the cereals and potato production in this province. The purpose of this study was to determine the possible effect of soil solarization on the population dynamics of Fusarium spp. The propagules under Hamadan climatic conditions. Pre-tarping irrigation to achieve the field capacity was carried out prior to the various treatments including the black and transparent polyethylene plastic sheets. The experiment was performed in a completely randomized block design with three replicates, in a naturally infested soil. After three, five and eight weeks, soil samples were collected from different soil depths in appropriate plots. The propagule numbers of Fusaria were counted through dilution plate method using selective Nash & Synder and PDA media. The results indicated that the propagules of Fusarium in treated soils (five and eight weeks treatments) were significantly decreased as compared with the three week treated and untreated control plots. Better results obtained with the transparent sheets after eight weeks, followed by treatments with five weeks of mulching. Accordingly, the hydrothermal control of the Fusarium foot and the root-rot disease seem to be effective under the cool and temperate area of Hamadan.

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The objective of this study was to evaluate effects of cow manure on soil hydraulic properties and bromide leaching in a sandy loam soil (coarse loamy mixed, Typic Torrifluvents). Manure was applied at 0, 30, and 60 tha^-1 at three replications in a completely random design. Three months after manure application potassium bromide (KBr) at rate of 300 Kg ha^-1 Br was uniformly applied on the surface. Soil bulk density, porosity, organic matter, and soil moisture at18 levels of matric potentials were determined. Soil samples to the depth of 105 cm at 15-cm increments were collected after 100, 200 and 400 mm of irrigation. Soil bulk density, porosity, organic matter content, and soil moisture at different levels of matric potential increased significantly with manure application. Manure application also significantly affected the hydraulic parameters. Bromide leaching was significantly lower in plots with manure application and the greatest leaching occurred at the zero manure application treatment. The center of mass evaluation indicated a relatively similar result with measured values.

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In order to achieve a sustainable management of land resources and to improve land quality, quantitative assessment of effective factors and soil quality indicators are required. The aim of this study was to evaluate variability of selected soil quality attributes in central Zagros affected by such factors as region, land use and management practices. Twelve sites were selected in three provinces including Chahar Mahal va Backtiari (Sabzku, Broujen), Isfahan (Semirum), and Kohkeloyeh va Boyerahmad (Yasodje). Different management practices were considered such as: protected pasture, intensive grazing, controlled grazing, dryland farming, irrigated wheat cultivation, legume-farming practice, protected forest, and degraded forest. Systematic sampling with taking 50 samples of surface soil in each site was carried out. The results of univariate and multivariate analysis revealed that all factors significantly influenced the spatial variability of selected soil quality attributes namely phosphatase activity, microbial respiration, soil organic matter, and total nitrogen. The results obtained from discriminant analysis indicated that all selected soil quality parameters could significantly be used as soil quality indicators in order to recognize and discriminate sustainable agricultural and forestry ecosystems and/or optimal management practices.

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This study was conducted to evaluate the effects of different levels of energy and protein on the performance of male broiler breeder chicks. Three hundred and sixty day-old Arian male broiler breeder chicks were used in a 2×3 factorial experiment with two levels of metabolizable energy (3050 and 3200 Kcal/Kg) and three levels of protein and sulfur amino acids (110% NRC, NRC and 90% NRC) in a completely randomized design with four replicates per treatment. Results obtained from the whole of the experiment’s period (0-49 days of age) indicated that level of dietary energy had a significant effect on body weight and daily gain (P<0.05). Increasing of the energy levels from 3050 to 3200 kcal/kg increased body weight (2216g vs 2314g) and daily gain (45.2 vs. 47.2 g per day). Dietary energy level had no effect on feed intake, feed conversion and carcass components. Increasing of dietary protein significantly increased body weight and daily gain and decreased feed conversion and percentage of abdominal fat pad (P<0.05). The results of this study indicated that we can fed Arian male broiler breeder chicks by using diets containing 3200 Kcal ME/kg and protein and sulfur amino acid levels according to NRC recommendation or 10% higher during 0-21, 21-42 and 42-49 days of age and achieve suitable growth rate and body weight.

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This study was carried out to evaluate the duration of time of feeding starter and finisher diets on live performance and carcass characteristics of female broilers. Starter diet was fed to 14 or 21 days of age. Finisher diet was fed beginning at 35 or 42 days up to 49 days of age. The results indicated that reduction of duration of feeding starter diet reduced weight gain (P<0.0071) and impaired feed conversion ratio (P<0.0002) up to 21d. Reduction of time of feeding starter diet caused a decrease in body weight at 21d (P<0.0071) whereas it had no effect on body weights at 42 and 49 days. Increasing time of feeding finisher diet caused a drop of the weight gain (P<0.0076) and impaired feed conversion ratio (P<0.0001) up to 42d but these differences were not significant up to 49d, suggesting a catch-up growth during 42 to 49d. There was no significant effect of dietary treatments on carcass characteristics at 49 days of age. Lowering time of feeding starter diet and increasing time of feeding finisher diet caused a significant decrease in pH, moisture and nitrogen contents of the litter.

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Due to the feeding on prickly shrub of Astragalus adscendes by an insect (Cyamophila dicora Loginva), a kind of the manna named Gaz-angubin is produced which it’s harvesting has a long history in Isfahan province. This manna is exclusively produced in Isfahan, Iran. In this research, a map of spatial distribution of this prickly shrub was provided. By random-systematic sample of line transects, biological criteria such as insect density, canopy coverage, branch and the soil moisture were measured. Multiple linear regression and nested design were used to analyses the response and predictor variables. The results indicated that the prickly shrub of Astragalus adscendens occupied the wet parts of mountainous areas of Isfahan and density of insect is highly related to the age, canopy coverage and soil moisture. By increasing the age of prickly shrub, the densities of insect are also increased. Regression analysis showed that the age of plant are more important in two areas of Kloseh and Lashokhm, while in Dareh-sibe area, soil moisture and the moisture of branches are more important. In other words, when the moisture is enough (e.g. Kloseh and Lashokhm areas), the age of plant has the paramount effects on insect density but when the area was suffered from drought, branches and soil moisture are more important.

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The soil potassium status and effect of soil physical and chemical properties on it were investigated using 109 surface soils (0-30cm) from four regions in Guilan province. Neutral molar ammonium acetate extractable K (K-NH₄OAc), boiling molar nitric acid extractable K (K-HNO₃) and water soluble K were determined. Results showed that CEC and clay were normally frequency distributed while distribution frequency of other variables such as silt organic carbon and pH were not normal and have significant skew and kurtosis. In addition sand, K-NH₄OAc and K-HNO₃ has logarithmic normal distribution. Water-soluble potassium was affected by sand, pH, O.C and K-NH₄OAc (R²_a=0.73**). Ammonium extractable potassium was affected by soluble potassium, non-exchangeable potassium and CEC (R²_a=0.72**). Boiling nitric acid was affected by exchangeable potassium and silt (R²_a=0.55**). Geographic distribution of K-NH₄OAc data shows amount of it in central parts of Guilan, particularly Sepidrood river watershed is more than other regions. Fomanat region soils have the less clay, CEC, K-NH₄OAc and K-HNO₃. According this study about 68.8 percent of Guilan soils was classified in the range of medium to very low potassium status.

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This study was conducted to evaluate the effects of four levels of irrigation (irrigation of plants after I₁ = 40, I₂ =60, I₃ = 80 , and I₄ = 100mm of evaporation from class A pan) and four plant densities(D₁ = 30, D₂ = 40, D₃ = 50 and D₄ = 60 plants/m²) on the seed yield and seed quality in three soybean cultivars(V₁=Hobit, V₂=Williams and V₃=Hill) in a split factorial design, based on the completely randomized blocks, with three replication for two years(2001 and 2002). The Irrigation treatments were assigned to the main plots, and the plant densities and cultivars to the sub plots. Results indicated that soybean seed yield was influenced by the different irrigation and plant density levels in the both years. Irrigation levels I₂ produced the highest and I₄ the lowest seed yield. It was also revealed that the plant density D₃ produced the highest and D₁ the lowest seed yields. Among the cultivars under investigation, V₂ produced the highest and V₃ the lowest seed yield . Seed oil and its protein contents both were affected significantly by the irrigation levels, plant densities and cultivars in both years. The plants receiving I₁ treatment had the highest and those having I₄, the lowest percentages of seed oil. Changes in the plant densities also affected seed oil and protein content. The plant density of D₁ caused the seeds to have the highest oil and lowest protein percentages. However, D₄ decreased oil and increased protein percentages. The highest water use efficiency was obtained from I₃ and that of the lowest value from I₁. The results also indicated that D₄ had the highest and D₁ the lowest water use efficiencies. Therefore, it could be concluded that the water use efficiency can be increased by increasing the plant density per unit area. The highest efficiency for biological and grain yield belonged to V₂ and V₁ respectively where as the lowest efficiency for those two mentioned characters belonged to V₁ and V₃, respectively. However, the treatment I₂V₂D₂ is recommended for higer the seed yield production per unit area.

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Under irrigation and in double-cropping system, a large amount of plant residue remains after harvest that along with the limited time for residue decomposition and complete seedbed preparation, necessitates reduced tillage and special residue management. In the present study, the effects of various seedbed preparation methods on vegetative growth, yield components and seed and oil yields of sunflower (Euroflor hybrid) were studied in a barley-sunflower cropping system during 2001 at the Agricultural Research Station, Isfahan University of Technology. Three residue management treatments (standing, partly removed and burned) along with five tillage systems (moldboard + disk chisel + disk disk moldboard and furrower as the minimum tillage) were laid out in a split-block design with three replications. Burning residue treatment significantly increased plant dry weight at various developmental stages and also head diameter. Number of seeds per head, 1000 seed weight, harvest index, and oil yield were non-significantly higher in the burned residue treatment. Seed yield was significantly higher in the burned and partly removed residue treatments. Moldboard + disk and chisel + disk treatments significantly produced higher plant dry weight at various developmental stages, head diameter and seed yield. Number of seeds per head, 1000 seed weight, harvest index, and oil yield were non-significantly higher in these treatments. Minimum tillage ranked the lowest for these traits. The results of this experiment indicate that chisel + disk treatment with the partly removed residues might be an appropriate seedbed preparation method in a barley-sunflower double planting under conditions similar to this experiment.

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An experiment was conducted with the male Ross broiler chicks from 1 to 42 days of age to test the effects of different dietary protein and lysine levels on performance, carcass characteristics, and N excretion. Treatment diets consisted of three levels of supplemental lysine in starter and grower period (0, 0.15, and 0.30 %) and the two levels of protein (20.84, 17.84 in starter, and 18.12, 16.12% in grower period) with 2900 Kcal ME/kg diet. The results indicated that the Reducing dietary protein decreased significantly the weight gain in starter, grower, and total period up to 6, 4.6, and 5.6%respectively (P<0.05). It also decreased the feed consumption in starter period (P<0.05). Decreasing dietary protein had no significant effect on gain to feed ratio and breast meat yield, but increased abdominal fat percentage significantly (P<0.05). Increasing dietary lysine increased the feed consumption in starter and weight gain, gain to feed ratio in grower and total period of the experiment (P<0.05). Increasing lysine in diet caused a significant increase in breast meat and tight yield, and percentage. Adding supplemental lysine reduced the N excretion in starter period significantly (P<0.059). N excretion reduced significantly by decreasing dietary protein (P <0.05). Dietary treatments had not significant effect on mortality percentage. The results of the present experiment indicated that with providing limiting amino acids and adding supplemental lysine to diet, the crude protein could be reduced up to 3 and 2 percent in starter and grower periods respectively. Reducing the crude protein had not adverse effect on the feed efficiency.

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In the current experiment seven catheterized broiler breeder hens were used at 60 weeks of age. Retention of ¹⁴CO₂ in the body of the hens following continuous infusion of NaH¹⁴CO₃ during each of tow-30-hr continuous infusion studies was determined. Oxidation rate plateau was established within two hours in each experiment. Recovery of ¹⁴CO₂ at the steady state in the first and second study were 91.09 and 87.55 percent respectively and were not significantly different. Mean breath ¹⁴CO₂ recovery was 89.32 percent and hence retention was 10.68 percent. Recovery of ¹⁴CO₂ in breath was not significantly affected by laying of egg or photoperiod. Recovery of ¹⁴CO₂ during the fed state was significantly lower than the fasted state. The results of this experiment indicated that, using of uncorrected data for the retained isotope into body, lead to 10.68 percent AA requirements underestimation in broiler breeder hens by indicator amino acid oxidation technique.