JWSS - Journal of Water and Soil Science

---

In this research some properties of the casein micelles in the raw and pasteurized milk were studied by electron microscopy. SEM and TEM were used to evaluate the differences in acidified casein micelles of raw and pasteurized milk at the Iso Electric Point (pH=4.6). Milk samples were taken from research pilot plant of The College of Agriculture. Milk was pasteurized by the L.T.L.T. method in the same pilot plant. The samples of raw and pasteurized milk were divided into two parts. One part of raw and pasteurized milk was acidified to the Iso Electric Point of caseins (pH=4.6) by lactic acid (9%) and then sample preparation for electron microscopy was done. According to the previous findings, results indicated that in the native pH, specially in fresh raw milk casein micelles were in spherical and individual form with the smooth surface. Aggregated casein micelles were present of acidified samples of the raw and pasteurized milk. Aggregation was the result of neutralization of electric charges in the isoelectric pH of casein and partial removal of micellar calcium phosphate. Results of both electron microscope confirmed each other and effects of heating on increasing of the casein micelle size during pasteurization were seen.

---

The brown spot disease is one of the seed-borne diseases of rice, found in the all stages of its growth from nursery to farm. It causes qualitative and quantitative damage on rice. Therefore, some studies carried out on the different aspects of this disease and the reaction of some cultivars of rice against the pathogenic fungous agent of the diseases. To do so, 120 isolates, isolated from plant samples were collected from the 91 paddy fields in Guilan. To isolate the pathogenic fungous agent of the disease, the collected samples were cultured on PDA and filter paper. According to the results, the present isolation related to Bipolaris with the 3 species : Bipolaris oryzae (Ito & Kurib.) Drechsler ex Dastur Bipolaris victoriae Nelson Bipolaris sp. The total isolataes were consisted of 15% Bipolaris oryzae, 75% Bipolaris -victoriae and 10% Bipolaris sp. The study of pathogenicity of isolation in these three species was applied to Khazar rice in desicator. The symptoms created by these three species were different from necrotic spots to leaf death. The results indicated that not only the symptoms but also the virulence in these three species were different. The virulence in B. oryzae was more than B. sp and this was more than B. victoriae. To study the reaction of some cultivars of rices to the pathogenic fungous agent, 8 cultivars of rice: “ Bejar, Khazar, Sepeedroud, Domsephid, Hassan saraee, Binam, Neda, Nemat” respectively were used in the two stages of the plant growth, to leaf in the seedling stage and heading. The results indicated that in seedling stage there was no significant difference between these cultivars with respect to the amount of infection. And in heading stage, according to “Dunken” test (5%) they divided into the 3 groups: “Neda, Sepeedrud, Khazar and Binam” with the lowest amount of infection were in the first group, “Bejar, Domsephid and Hassan saraee” classified in the second group and “Nemat” was in the third one. But there was no significant difference between them according to the variance analysis table.

---

The biological parameters of cabbage aphid, Brevicoryne brassicae (L.) was studied in the laboratory conditions under the three constant temperatures (20, 25 and 30 ºC), RH 60±5% and a photoperiod of 16:8 (L:D) using 40 first instar nymphs. Among nymphs, 40%, 55% and 10% of them completed their nymphal period in 20, 25 and 30 ºC, respectively and developed to adult stage. In 30 ºC, the most biological acitivities of aphid were disrupted and the most individuals (nymphs and adults) were killed. Most developmental periods, longevity and the amount of reproduction in 20 ºC were significantly greater than other temperatures. In temperatures 20, 25 and 30 ºC the last individual of a cohort died in age of 33, 29 and 16 days, respectively. The life expectancy of cabbage aphid in the first day of experiment was 13.93, 10.50 and 7.19, respectively according to the mentioned temperatures. There was a little difference between net reproduction rates in temperatures 20 and 25 ºC (16.74 and 15.92, respectively). Net reproduction rate was reduced extremely in temperature 30 ºC (1.75). The intrinsic rate of the increase in the temperatures 20, 25 and 30 ºC were 0.187, 0.226 and 0.042, respectively. The results indicated that 25 ºC was the optimal temperature for biological activities of B. brassicae and its highest population growth was observed at this temperature.

---

The vast and diverse rangelands of Iran require the selection of appropriate methods for grazing intensity measurement in the different vegetation types. Methods can be compared on the bases of time and budget as well as their accuracy. In this study nine methods of the utilization measurement were conducted on the E. ceratoides stands of Hanna exclosure Semirom, Isfahan province. The duncan multiple range test was used to compare mean utilization percentages obtained from the different methods, with paired cage method data was used as control group. Analytical Hierarchy Process (AHP) was also used to compare methods for accuracy, time and budget. The means from reference unite, twig length, production index, plant count and stem count methods had significant (p<0.05) differences compared with control group but were comparatively time consuming and more expensive than other methods. The height-weight method resulted in an estimate with no significant difference with the control group. This method was also fastest and least expensive among methods with the accurate results (p<0.05).

---

In this study, the simulation of the BORKHAR plain aquifer located in north-east of Isfahan was done for the estimation of the hydrodynamic coefficients and for the preparation of the prediction and management model with the purpose of the study of the water table surface situation in the next years. The study of the geological situation of the plain and the report of the drilling of its exiting wells indicated that the BORKHAR plain has two kinds of aquifer: confined and unconfined. According to the field data related to the unconfined aquifer, a part of this aquifer was selected for the mathematical simulation. The calibration model for the estimation of the K and Sy. coefficients was done by dividing the plain into four geohydrologic units and by using the PEST, a module of the MODFLOW model. The situation of the water table level during 1380-1390 was studied according to the different management options by the calibration model. If the trend of the exploitation doesn’t change during the next ten years, we will confront with a maximum drop of 48 meters. As a practical way for preventing from this drop, it was suggested that the exploitation management reduce the 30 percent of the demand. One of the most important result of this will be the 26 percent reduction of the drop. By developing an optimization model and by imposing the necessary constraints on the critical regions, and transferring water from other parts, it seems that the trend of the drop will be controllable at a admissible level (less than 10 meters until 1390). Using the optimization model will make a change in the increasing trend of the drop and an improvement in the situation of the aquifer.

---

In order to determine the water production functions for winter wheat (Variety, C73,5), an experiment was conducted in through of a complete randomized block design with 9 treatments and 3 replications in Mashhad region. While the first treatment (as a control treatment) was selected on the basis of irrigation in all growth stages of growing season, six treatments were selected on the basis of an irrigation cut in the six stages of growth season and two remaining treatments were also selected on the basis of a constant reduction of irrigation to the amount of 20 and 60 percent. In general the water stress was caused that the amounts of depth percolation were calculated negatively which was an indication of the water uptake from below the root zone. According to results, models of the yield in per unit of area had a higher correlation coefficient of determination in relation to the models of the yield in per unit of water. The derived sensitivity coefficients indicated that the winter grain formation and flowering stages were respectively the most sensitive stages of the growth season stages to the water deficit. There are some differences between these computed sensitivity coefficients and the amounts reported by the other researchers. Probably the variety, degree of stress, the climatic conditions and some unknown factors may explain these differences.

---

This study shows how multiobjective programming, compromise programming and filtering techniques could be used to manage scarce resources. Data were collected from a sample of 109 Rafsanjan pistachio producers. The aim of the program was to make a compromise between the objectives of profit maximization, the maximization of the area under pistachio gardens and also maximization of the groundwater use. The multiobjective programming approach and filtering techniques were used to find the efficient set among these objectives. A compromise between the objectives was established by the compromise programming method. Although none of the above three objectives achieved completely in the compromise solution, it became nearer to the ideal point on the assumption that the importance of three objectives was the same. By omitting this assumption and considering the objective weights based on decision maker preferences, the compromise solution might become nearer to the ideal point.

---

Due to the existence of salinity and high temperature and sensitivity of some plants in most regions of Iran, especially in Khoozestan, there are a lat of difficulties in the planting and husbandry of lawn. Therefore an experiment was carried out under field conditions, to investigate the effect of seven levels of salinity as: Karun river water with EC of 1.09, distilled water (0.01) and irrigation with hand made salinity of 3, 6, 9, 12 and 15 dS/m on the growth and development of three types of lawn namely: Lolium perenne L. cultivar Barball, Festuca arundinacea cultivar Kentaky-31-C and Cynodon dactylon cultivar Primo in the form of a 7×3 factorial with a completely randomized design in 3 replication. A number of leaves on the main shoot and tiller, fresh and dry weight of leaves, leaf area and a number of tiller per plant were recorded. According to the results, it was revealed that the effect of salinity, Genus and interaction were significant (P<0.05) on growth parameters. In all salinity levels, Cynodon dactylon, in comparison to the other two genus displayed the highest rate of growth, while between the two other genus there were no significant differences. In addition, it was revealed that the number of leaf on the tiller and main shoot in Cynodon dactylon at a salinity of 15 dS/m was 5.1 and 4, respectively. Whereas in others, no leaves were initiated at this level of salinity. It was also appeared that at salinity of 15 dS/m, the growth of leaf area, the fresh and dry weight of leaves greatly decreased in Lolium perenne and Festuca arundinacea, while Cynodon dactylon still had growth ability. It was concluded that the number of tiller per plant and high of the plant was less affected by salinity, compared to the other growth parameters in all of genus.

---

Over-grazing may induce changes in the dynamics of plant residue carbon and soil organic carbon (SOC). The objective of this study was to evaluate the litter quality of three dominant pasture species, and the relationship between litter quality and C dynamics under different range managements in native rangelands of SabzKou. Aboveground litters from three dominant species including, Agropyron intermedium (AP), Hordeum bulbosum (HB) and Juncus stenophylla (JU) were collected in an area protected from grazing for 15 years. Concentrations of N, P and K in litter samples were determined. Litter decomposition was also studied by using a litter bag experiment. Bagged litters were incubated under field conditions at grazed and ungrazed sites for one year. Concentrations of N in litters were 1.37, 1.36 and 0.98, respectively, for AP, JU and HB. Assuming 50 % C in the litter, C/N ratios of litters were 37.2, 37.3 and 51.1, respectively, for AP, JU and HB. The litters of AP, JU and HB contained, respectively, 0.13,0.12 and 0.21 % of P, and 1.04, 1.01 and 1.72 % of K. Results indicate no significant (p>0.05) and consistent difference in litter decomposition rates between grazed and ungrazed areas. The three pasture species, however, showed significant (p<0.01) differences in litter decomposition rate. It is appearing that the trend in litter decomposition of these plant species correlates initially with litter C/N ratio, but other quality parameters of litter as well as soil environmental conditions would likely affect the litter decomposability in advanced stages of decomposition process.

---

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.

---

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.

---

The appropriate planting pattern of safflower in summer planting might be different from the planting pattern suitable for spring planting, and this has not been determined under Isfahan environmental conditions. A field experiment was conducted in the summer of 2000 at the Agricultural Research Station, Isfahan University of Technology, using a randomized complete block design with a split plot layout and three replications. Main plots consisted of three row distances (30 cm flat and 45 and 60 cm on bed), and sub-plots included three planting densities (30, 40, and 50 plant m^-2). The experiment was planted in June 13 using local safflower variety of Isfahan, named Koseh. Leaf area index, number of heads per branch, number of seeds per head, 1000-seed weight, seed yield per plant and harvest index were not significantly effected by row distance. Increase row distance significantly enhanced most developmental stages and increased number of branches per plant and per square meter, but significantly decreased number of heads per plant and per square meter and seed and petal yields. The highest seed and petal yields (3841 and 373 kg per ha, respectively) were obtained with 30 cm row distance. Plant density had no significant effect on number of branches per plant, number of seeds per head, 1000-seed weight and seed yield per plant and per unit area. Plant density significantly enhanced most developmental stages and increased leaf area index, number of branches and number of heads per square meter, but significantly decreased number of heads per branch and per plant, petal yield and harvest index. The highest seed yield without petal clipping (4341 kg per ha) was obtained with 30 cm row distance and 50 plants m^-2 treatment. The results obtained in this experiment indicate that this planting pattern might be appropriate for summer planting of safflower under conditions similar to this experiment.

---

In orther to determine the critical period for weed control in the Chitti bean (Phaseolus vulgaris) line KS-21467 a field study was conducted at the Bean Research Station of Khomein by a randomized completele block design in 2001 and 2002. The treatments included weed free and weed infested period until 20, 28, 36 and 44 days after planting (DAP) with two weed free and weedy checks. The results indicated that the critical period at 5% allowable yield loss was 20-53 DAP (between first-trifoliate and flowering stages) in 2001 and 35-51 DAP ( between blossom and flowering stages) in 2002. Weed dry weight decreased averaglly 81% in weed-free period until 44 DAP compared to the weedy check. Yeild decreased averaglly 63% in weedy check compared to the weed free check. Weed competition increased the height of bean, wherease 100-seed weights and the number of seeds per pod were not substantially affected. There was a negative and significant correlation of weed dry weight with the number of pods per plant, the number of seeds per plant and yeild.

---

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.

---

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.

---

In this study changes in microstructure of casein micelles in raw and pasteurized milk were investigated by SEM and TEM. Milk was pasteurized by L.T.L.T. method (Temperature: 63 ^oC_ Time:30 minute).Samples of raw and pasteurized milk were taken from research pilot plant of The College of Agriculture. Each sample was divided into two parts. One part of each sample was directly prepared for SEM and TEM, whereas the second part were renneted at 2 ^oC and kept at this temperature for 24 h. and then prepared for evaluation by electron microscopes. Results indicated that in native state, particularly in raw milk casein micelles are in spherical shape with smooth surface and in the single form. The samples, which stored in the cold were under the effect of the rennet, encounter of filamentous status that might be due to the changes occurred in kappa-casein following the action of rennet along with partial removal of beta-casein and micellar calcium phosphate. Micrographs of casein micelles in pasteurized milk indicated that thermal condition during pasteurization had influenced on increasing of casein micelles size.

---

The meat productions are the most popular among different food products. On of the serious problems of this kind of products may be the change of the physical and chemical properties. The Restriction of the use of synthetic antioxidants have prompted the extensive research on the effect of the natural antioxidant and replacement of synthetic antioxidant with the natural ones. In this study, the effect of α-tochopherol (vitamin E) and propyl gallate on German sausage was evaluated. Four different German sausages were formulated and prepared in 30 Kg batches as follows: control without antioxidant, sausages plus α- tochopherol (200 or 500 ppm) and sausages plus propyl gallate (200 ppm). Twelve Kg of the samples were filled into cellulosic casings and the other 18 Kg in polyamidic casings. All samples were cooked. One third of the packed samples were stored at (4˚C ± 1) for 10 days and the rest were stored at (– 18 ˚C ± 1) for 6 months. The extent of autoxidation for samples were determind by peroxid and TBA values. During the storage period, autoxidation rates of control samples were more than other treatments. Propyl gallate was more effective in reduction of autoxidation than α- tochopherol treatments. Addition of 500 ppm vitamin E was more effective than 200 ppm. Significant differences were observed among treatments (P< 0.05). The study of the shear strength of the stored susages at the (4 ºC ±1) for the 10 days indicated that the most shear strength is seen in the cellulosic casing samples. The same results obtained for the stored samples at the (-18 ºC ±1) for the 6 months.

---

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.

---

Manganese toxicity occurs in many agricultural and natural ecosystems under the various soil conditions such as the nature of substrate, acidity, flooding or vicinity to the mining areas. The objective of this work was to study the effects of excess Mn in the growth medium on three important crop species, namely rice (Oryza sativa L. cv. T. Hashemi), maize (Zea mays L. cv. SC.704) and sunflower (Helianthus annuus L. Mehr). Plants were cultured in the hydroponic medium under controlled environmental conditions and treated with 0 (control), 25 50, 75 and 100 µM Mn for 12 days. Dry mass production, the effect of supplemental Mg and Ca on the toxicity expression, root respiration and K⁺ leakage from shoot and root tissues were studied under the Mn treatments. In order to study the effect of light intensity on the expression of toxicity symptoms, plants were cultured under the different light conditions, thereafter their growth and metal uptake and transport were studied. Sunflower plants treated with the 50 µM Mn and higher, showed dark-brown spots associated with the trichomes on the leaves and petioles. Maize plants developed interveinal chlorosis and any visual leaf symptoms was observed in rice. In all of the studied species, a great portion of the absorbed Mn was translocated into shoot, the highest transport was observed in sunflower and the lowest in maize. No significant correlation was observed between the expression of Mn toxicity and the accumulation rate of Mn. Growing under the low light intensity, in addition to the lowering biomass production, increased or decreased the toxicity effect depending on species. Mn-toxicity-induced root respiration was not associated with the differential response of species to Mn toxicity. In contrast the change of K⁺ leakage from shoot and root tissues was well correlated with the toxicity response of tested plants.

---

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.