JWSS - Journal of Water and Soil Science

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Sorghum grain is an important cereal to be cultivated in tropical and sub-tropical areas. The extension of its cultivation and application in animal and poultry diets may reduce the need for imported corn. In order to determine the nutritive value of sorghum, 36 sorghum grain (SG) varieties and one type of corn were grown at the same location. The grains were analyzed for their nutrient composition. Results from of proximate analyses showed that the ash, crude protein (CP), phosphorous (P) and acid detergent fiber (ADF) contents of SG were 1.72±0.54, 11.6±1.18, 0.34±0.03 and 8.35±3.93, respectively. The ether extract (EE) of SG was lower than Iranian and imported corns. Iranian corn had higher amounts of CP (10.7%), EE (5.9%) and CF (3.3%) than the imported one (7.8, 4.2 and 2.25). Tannin contents of low and high SG varieties were 0.021% and 0.998%, respectively. The apparent and true metabolizable energies (AME and TME) of SG were decreased due to increasing the tannin contents. The values of TME_n (3853, 3771 and 3213 Kcal/kg) showed significant differences (p < 0.05) among low, medium and high tannin sorghum (LTS, MTS and HTS) varieties. However, in comparison with the SG, the corn had higher amounts of TME (3853, 3771 and 3213 VS. 3947 Kcal/kg). LTS had the highest AME (3453 Kcal/kg) among all the grains, while there were no significant differences (P > 0.05) between MTS (3458 Kcal/kg) and the two corn grains (3406 Kcal/kg).

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An experiment was conducted in order to study the possibility of compensatory growth by changing dietary nutrients concentration in the female Arian broiler chicks using a completely randomized design by means of standard and diluted diets. By standard diet is meant diet recommended by Arian’s guide catalogue and by diluted diet is meant the diet used in Iran broiler farms. However, both diets contain the same nutrient/energy ratios. Chicks in the seven treatments received in their starter, grower and finisher stages standard and standard and standard, standard and diluted and diluted, diluted and standard and diluted, diluted and diluted and standard, diluted and standard and standard, diluted and diluted and diluted, standard and standard and diluted respectively. Furthermore each treatment contained three replicants and each replicant contained 30 chicks. This experiment was conducted in autumn using 630 female Arian broiler chicks for eight weeks.

 It was concluded that weight gain of chicks receiving standard diets during all stages of their growing period was the same as the chicks receiving diluted diet during their starter period and standard diets during grower and finisher periods. Feed consumption and feed conversion ratio of these treatments were statistically lower than other treatment groups. Furthermore, production index and percentage of mortality was better than other treatment groups. Likewise, viscera% and abdominal fat% remained significantly constant in all treatment groups. But the cost of feed per unit of live body weight was lower in the treatment receiving diluted diets in all three stages of their growing period.

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Excessive application of sewage sludge leads to the accumulation of potentially toxic elements in soils. The objective of this greenhouse study was to examine the DTPA–extractability of Fe, Zn, Cu, Mn, Pb, Cd, Ni, and Co in relation to soil pH and to investigate the concentrations of these metals in corn (Zea mayz). The study was conducted using a factorial experiment in a completely randomized design with three replications. Sewage sludge was applied at 0, 50, 100, and 200 t/ha on four soils [Langaroud (pH= 4.8), Lahijan (pH= 5.7), Rasht (pH= 6.8), and Isfahan (pH= 7.9)]. Application of sewage sludge significantly increased DTPA-extractable Fe, Zn, Cu, Pb, Cd, and Ni in all soils. The increasing effect was in accordance with sludge level. Langaroud soil had the highest and Isfahan soil the lowest levels of DTPA-extractable metals. Application of sewage sludge increased plant growth and metals in the foliage of corn plants. The metal concentration in corn tissues also increased with decreasing soil pH. Overall, the application of sewage sludge as an organic material, particularly in acid soils, may increase availability of heavy metals, which may, in turn, result in soil pollution. Therefore, addition of sewage sludge to soils should be managed on the basis of the changes in soil heavy metal concentration.

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A great number of studies have been conducted on the role of Azotobacter - a free living N₂-fixer - in agricultural soils, but our information is lacking on the importance of Azotobacter in pasture soils. This research was conducted to study the relationship between ecological and edaphical factors with the population of the bacteria in soil. Soil samples were taken from two sites in Azarbaidjan (Mishou-dagh and Khadjeh), having different ecology, soils and vegetation types. We investigated also the effect of inoculation of rhizosphere with soil-isolated A. chroococcum on the growth of wheat (Triticum aestivum L. cv. Omid) during 56 days of growth in a pot experiment. The treatments included: 1) inoculation with A. chroococcum (+A), 2) N fertilizer at a rate of 35 mg/Kg as (NH₄)₂SO₄ (+N), 3) +A+N and 4) –A–N as control with four replications. Results showed that the population of Azotobacter chroococcum correlated positively with organic carbon and negatively with soil pH. In soils covered with vegetation the population of bacteria was higher than that in uncovered soils and the highest population of bacteria was found in soil samples collected from the rhizosphere of grass species and the lowest in that of legume species. In inoculation experiment, shoot and, particularly root growth, increased in the order of +N, +A and +A+N in comparison with control (–A–N) plants. These treatments also stimulate uptake and transport of K into shoot. Interestingly, the effect of +A treatment was significantly higher than that of +N and +A+N treatments. The same results were obtained for nitrogen. A higher uptake and particularly transport of K into shoot was attributed to low molecular weight organic molecules produced in inoculated roots and transport K into shoot. Results showed that inoculation with Azotobacter not only enhanced growth and chlorophyll content, but also stimulated uptake and translocation of ions into shoot. The stimulatory impact of inoculation is most likely a general effect that could also be important in micronutrients translocation into shoot.

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Drought stress is one of the most important environmental stresses in reduce of growth and plants production. Determination of resistance mechanisms to environmental stress in plant improvement is very important. In order to , experiment with osmotic potentials of PEG (zero (control), -4, -8 & -12 bar) and alfalfa genotypes was done. The selected alfalfa genotypes namely, Yazdi(tolerant), Nikshahri(moderate) and Ranger(sensitive) were grown in hydroponic culture. After 4 weeks, they were harvested in order to determination of proline accumulation and Ca⁺², K⁺ and Na⁺ concentration. The data showed with increasing of drought stress, proline accumulation were increased, but its rate was different among genotypes and organelles. Concentrations of K⁺, Na⁺ and Ca²⁺ increased with increasing of osmotic stress and there was significant different between genotypes. The K⁺/Na⁺ ratio in the shoots and roots of plant was decreased, when drought stress increased. Morphological and biochemical data showed Yazdi genotype was more tolerant to drought stress in compare with studied genotypes.

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Sewage sludge and effluents, as cheap sources of irrigation water and fertilizer, can supply plants with water and nutrients however, contamination of these sources with heavy metals and the possibility of human food chain contamination using these sources should be considered. In this research, the effects of industrial sewage sludge and effluents on concentration of some nurtients, heavy metals and sodium and dry matter yield of wheat (Triticum aestivum), barley (Hordeum vulgare) and corn (Zea mays) were investigated. The experiment was carried out in a greenhouse using a complete randomized design with four replication. The treatments comprised well water, well water + sewage sludge(50 tons/ha), and three industrial effluents from Iran Polyacryl factory including the cooling tower, the over flow and the factory outlet effluents. Chemical analysis showed the following results: The concentration of the elements in the sludge and the effluents were below the critical contaminating levels. The application of the treatments did not supply enough nitrogen for corn the cooling tower effluent could not supply enough nitrogen for wheat and barley all the treatments supplied enough P for wheat. None of the treatments could supply enough P for corn. The cooling tower, over flow and the factory outlet effluents could not supply enough P for barley, the micronutrient and heavy metal concentrations in the plant tissues using the effluents and the sewage sludge were higher than those for well water the dry matter yield of plants’roots and shoots was highest using well water + sludge and in comparison with the well water, effluents could increase the shoot dry matter yield.

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Sunflower (Helianthus annuus L.) can have an important role in vegetable oil production. Also, appropriate soil fertility is necessary to obtaine higher seed yield and quality of the crop. This experiment was conducted to investigate the effect of fertilizer treatments of macro and micronutrients on seed yield and other agronomic traits in sunflower. The effects of thirteen fertilizer treatemts (as main factor) were investigated on agronomoic traits of two hybrid cultivars, "HiSun33" and "Euroflor" (as sub factor) in a randomized complete block design with three replications. The results showed that there was significant interaction between fertilizer treatments and cultivars for most of the traits and the effects of fertilizer treatments were dependent on the cultivar. Almost all of the fertilizer treatments of N, P, K, Fe, Zn and Mn either significantly or non-significantly decreased the means of head diameter, 1000-seed weight, seed yield/plant, seed yield and oil yield in Euroflor cultivar however, in HiSun33 cultivar, each of N, P, and K fertilizers had no significant effect on seed yield. Application of Zn and Mn fertilizer in soil or spraying them on plants had no significant effect on seed yield and yield components in HiSun33 cultivar however, application of Fe feritilizer (Sequestrene) significantly increased the seed yield of this cultivar and had no significant effect on its seed oil. In HiSun33, seed yield and oil content for treatments of control, NPK and NPK+Fe were 4946, 5155 and 7090 kg/ha and 40.72, 43.10 and 43.07 %, respectively. The effects of fertilizer treatments on oil concentration of seed were not significant, thus the variation of oil yield was due to the seed yield. The correlation coefficients and regression analysis showed that seed weight and head diameter were most important seed yield components,. In general, it seems that in a soil conditions like that of this experiment, Fe fertilizer can increase seed and oil yield in HiSun33 cultivar.

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The influence of Nitrogen (N) rates on mineral nutrient uptake in stem and seeds, proline and carbohydrate in flag leaves of Wheat (Triticum aestivum L . Var Chamran) under saline conditions was studied in a field experiment in 2003 and 2004. The experiment was conducted using a split plot design with three replications. The treatments comprised five levels of salinity: 1.5, 5, 10, 15 and 20 ds/m in main plot and three nitrogen levels: 50 , 100 and 150 kg N/ha in sub plot. Salinity treatments were applied in a clay–loam soil by water with NaCl and CaCl₂ (5:1 by wt ). The results showed, the nutrient uptake was influenced by both salinity and N treatments. With the Exception of magnesium in seed, salinity increased nitrogen, calcium and magnesium concentrations in seed and stem in both years. By increasing salinity levels, the concentration of potassium in stem and seed decreased and Sodium concentration increased. In the stem the concentration of Sodium in the 20 ds/m was about 17 and 22 times more in the first and second year, respectively. In these experiments, by increasing salinity and nitrogen treatments, proline concentration in flag leaves increased in the two stages (flowering and milky stages) in both years. Salinity had similar effect on carbohydrate accumulation in both stages, but nitrogen treatment had two different effects on carohydrate concentration. In flowering stage, by increasing nitrogen application, carohydrate concentration increased but in milky stage decreased.

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Azotobacter chroococcum is an important PGPR (Plant Growth Promoting Rhizobacteria) producing compounds needed for plant growth. The aim of this research was to study the effects of different native strains of Azotobacter chroococcum on growth and yield of wheat under greenhouse counditions. Seeds of spring wheat (Triticum aestivum L. var. Pishtaz) were inoculated with some Azotobacter chroococcum strains capable of producing IAA, HCN, sidrophore and fixing molecular nitrogen. The inoculation of wheat with those strains had a positive, significant effect on biological yield, seed protein percentage, thousand seed weight, leaf area, N, P, Fe and Zn uptake, in particular, by wheat. The increased growth of wheat was most likely due to the production of IAA and enhanced nitrogen fixation by inoculated strains. Some strains of Azotobacter chroococcum native to Chaharmahal va Bakhtiari are established as PGPR. Results also support the efficiency of Azotobacter chroococcum as an important biofertilizer in wheat cropping systems. The selected strains had a significant effect on wheat growth and yield, including biological yield and seed quality under greenhouse counditions. This beneficial effect of Azotobacter chroococcum on wheat is attributed mainly to IAA production and, to some extent to non symbiotic nitrogen fixation in the rhizosphere. So, these strains can potentially be used to improve wheat nutrition of micronutrients such as Fe and Zn, in particular.

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Rapeseed (Brassica napus L.) is one of the oilseed crops in the temperate regions and is adapted to different climate conditions. This crop can have an important role in production of vegetable oil, and providing appropriate soil fertility can increase its seed and oil yield. In order to investigate the effect of N, P, K, Fe, Zn and Mn on seed yield and other agronomic traits of rapeseed, an experiment was carried out at the Research Farm of Isfahan University of Technology in 2006. The experiment was arranged as split plot in a randomized complete block design with three replications in which eleven fertilizer treatments and two cultivars of rapeseed (Ocapi and Zarfam) were considered as the main and sub factors, respectively. The results showed that there was no significant effect of fertilizers on days to maturity, but application of NPK+Fe significantly increased the plant height in both cultivars. The fertilizer treatment had no significant effect on the number of pods per plant and seeds per pod. The interaction effects indicated that application of N, P, K, NP and NK significantly increased 1000-seed weight in Ocapi cultivar however NPK+Fe significantly decreased 1000-seed weight and non significantly increased seeds per pod in Zarfam cultivar. Application of N, NPK and NPK+Fe increased the seed yield by 13, 7 and 43%, respectively. Averaged over two cultivars, N significantly increased seed oil content, but significant interaction between fertilizers treatments and cultivars indicated that application of K and NP significantly reduced the seed oil content in Zarfam cultivar. Fertilizer treatments of N, NPK and NPK+Fe had higher effects on seed oil content and oil yield and means of these traits for fertilizer treatments of control, N, NPK and NPK+Fe were 39.7, 41.7, 39.4 and 39.8%, and 681.1, 816.4, 730.2 and 983.3 kg/ha, respectively which indicate that N and Fe increased the seed and oil yield in both cultivars. However, the application of Zn and Mn had no significant effect on seed yield and seed oil content. In this study, the variation of seed yield and oil yield was mainly due to the variation of number of pods per plant and seed yield, respectively. In conclusion, it seems that in soil and climatic conditions like this experiment, application of N and Fe can be economically important and increase the seed and oil yield in rapeseed.

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This study was conducted to investigate the effects of thirteen fertilizer treatments (as main factor) on agronomic traits of two local cultivars (as sub factors) of sesame (Sesamum indicum L.), "Mobarakeh" and "Ardestan" in Isfahan by using a randomized complete block design with three replications. The results showed that applying fertilizer treatments of N, P, K, Fe, Zn and Mn had no significant effects on yield components, seed yield and oil yield. However, comparing the control treatment, simultaneous application of all fertilizers significantly reduced days to maturity. Significant interaction between cultivars and fertilizer treatments was observed for seed oil content, as application of N, P, NPK and NPK+Fe+Zn in Mobarakeh and application of N+K in Ardestan reduced seed oil content. However, the other fertilizer treatments had no significant effects on this trait. The Mobarakeh cultivar compared to Ardestan had significantly higher plant height, higher seeds per capsule, lower 1000-seed weight, higher seed yield per plant and per hectare and higher oil yield. Seed yield for Mobarakeh and Ardestan cultivars were 1646 and 1169 kg/ha and their seed oil contents were 52.88% and 53.81%, respectively. The correlation coefficients and regression analysis showed that the variation of seed yield was mostly due to the number of capsules per plant and seeds per capsules, thus these two traits were the most important yield components. Oil yield had a very high correlation coefficient with seed yield (r=0.99^**), whereas its correlation with seed oil content was very low (r = -0.10^ns). Therefore, it seems that seed yield was the main cause of higher oil yield.

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In order to investigate the effect of sugar plant effluent on shoot solute percentage, yield components and grain yield of two wheat cultivars, a two year field experiment was conducted on a farm near Eghlid sugar plant during 2004-2005. Treatments consisted of two wheat cultivars (Alamot and Zarin) and two irrigated treatment: irrigation with effluent and irrigation with spring water (control). The statistical design was a completely randomized factorial with three replications. The results showed that under effluent treatment, nitrogen, phosphorus and calcium percentage increased in shoot, and Fe, Mn, Zn, Cu and B concentration decreased. However, effluent treatment had not any significant effect on K, Mg and S concentration. The results showed that N percentages in Alamot and Zarin cultivar under control treatment were 2.41 and 2.54% and under effluent treatment were 3.28 and 3.41%, respectively. P percentages under control treatment were 0.42 and 0.47% and under effluent treatment were 0.46 and 0.51%, respectively. Ca percentages under control treatment were 0.29 and 0.32% and under effluent treatment were 0.46 and 0.51%, respectively. In both years, the lowest number of tiller, number of spike, number of kernel per spike, thousand kernel weight, grain yield and harvest index were obtained from effluent treatment in the two wheat cultivars whereas this reduction was higher in Alamot than Zarin cultivar. In Alvand and Zarin cultivars, the lowest number of tiller per plant with 2.33 and 2.50, number of spike per plant with 1.83 and 1.92, number of kernel per spike with 31.67 and 32.50, grain yield with 5233 and 5532 kg ha^-1 and harvest index with 32.03 and 33.53% and water productivity with 0.72 and 0.75 kg m^-3 were respectively obtained from effluent treatment compared to control. Thus, the results showed that using sugar plant effluent could decrease grain wheat quality and wheat grain yield.

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Understanding distribution of soil properties at the field scale is important for improving agricultural management practices and for assessing the effects of agriculture on environmental quality. Spatial variability within soil occurs naturally due to pedogenic factors as well as land use and management strategies. The variability of soil properties within fields is often described by classical statistical and geostatistical methods. This research was conducted to study what factors control the spatial variability of soil nutrients using an integration of principal component analysis and geostatistics in Appaipally Village, Andra Pradesh, India. 110 soil samples were randomly collected from 0-30 cm and prepared for laboratory analyses. Total N, available P, Ca, K, Na, Mg, S, B, Mn, Fe, Zn were measured using standard methods. Statistical and geostatistical analysis were then performed on raw data. The results of PCA analysis showed that 4 PC's had Eigen-value of more than 1 and explained 71.64 % of total variance. The results of geostatistical analysis revealed that three PC's had isotropic distribution based on surface variogram. Spherical model was fitted to all PC's. Ranges of model were 288 and 393 m for PC1 and PC3 respectively. On the other hand the range for PC2 was significantly different (877m). The most important elements in PC2 such as Fe, Mn, and Zn probably had similar range of effectiveness (700-900m). The comparison of PC's distributions indicated that PC1 and PC3 including total N, available Mg, K, Cu, Ca and P, were in accordance with farming plots dimensions and management practices. Therefore, it is necessary to improve the appropriate fertilizers used by farmers. The pattern of PC2 distribution was not consistent with farmer's plots, but had the best concordance with soil acidity. Therefore, the most correlated elements with this PC including Fe, Mn, and Zn are mainly controlled by soil acidity and not affected by management practices. However, spatial variability of these elements in areas lower than critical values should be considered for site-specific management.

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Many researchers have reported positive effects of converter sludge and slag, two by-products in Isfahan iron melting factory. In this work, the optimum rate of application and the availability of some essential elements (for plant growth) in the converter sludge and slag for corn were investigated. The converter sludge contains about 64% Fe ІІ and ІІІ oxides and some other essential elements for plant growth. The slag also contains 17% iron oxides, 52.8% calcium oxide as well as considerable amounts of some other elements. Treatments included a control, Fe-EDTA foliar spray with 5 in 1000 concentration, application of sludge in 4 levels (L1, L2, L3 and L4 equal to 5.83, 13.33, 20.83 and 26.67 ton/ha, respectively) and application of slag in 4 levels (S1, S2, S3 and S4 equal to 3.20, 7.28, 11.36 and 15.44 ton/ha, respectively) which supply 1, 2, 3 and 4 times as much as soil test recommends, based on AB-DTPA extractable Fe in the soil. Corn (Zea mays) single cross 704 was planted for the experiment. Applications of the two compounds increased the soil extractable Fe and Mn, decreased Mg but the treatment did not change the soil-extractable Zn, Cu and Ca. The corn yield also increased due to the applications of the two compounds and the maximum yield was related to L3, L4, S3 and S4 treatments. The foliar application treated the leaf chlorosis and increased the silage, grain and leaf + stalk yields however, this was not as efficient as sludge and slag application. Also applications of the two compounds increased the Fe, Mn, Zn, Cu, Ca and Mg uptake by corn. The L3 and S3 treatments can be recommended as the proper levels of these compounds as iron fertilizer.

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Organic matter (OM) and total N (N) are relatively low in majority of the calcareous soils in Iran, and continuous use of N fertilizer would impair the quality of surface and ground water and creates other environmental hazards. Therefore, the combined use of N fertilizer and organic wastes is important to partly supply plant N requirement, improve physico-chemical properties of soil and conservation of environment. The present study was initiated in order to study the effect of two organic wastes with and /or without N enrichment on the growth and chemical composition of paddy rice and some characteristics of the soil in pot experiment. The experiment was carried out in factorial manner in a completely randomized design with three replications. Treatments were two organic matter sources (municipal solid waste compost and cow manure), four OM rates (0, 1, 2, and 4%) and three N levels (0, 75, 150 mg kg-1 soil as urea). Application of compost and cow manure increased top dry weight of rice. The highest growth of rice was obtained with 4% compost and 150 mg kg-1 N. Rice growth increased up to 2 % cow manure and was suppressed with the higher rate, due to build up of soluble salt in soil. Enhancing effect of N on rice growth was only observed with 1% cow manure and at high level of cow manure rice growth was decreased probably due to rise in soil salinity or ammonium toxicity. The mean concentration of N increased by the addition of cow manure, whereas decreased with compost application. Soil N application enhanced the mean concentration of N, and iron (Fe) and magnesium (Mn). Rice plants enriched with either of the two organic wastes accumulated more phosphorus (P), potassium (K), N, Fe, Mn, chloride (Cl) and sodium (Na) than control plants. Post harvest soil sampling indicated that organic matter significantly improved all chemical characteristics. Furthermore, soil treated with cow manure had higher soluble salt (ECe), Cl, K, OM, total nitrogen, available P, Fe and Mn and lower Zn, Cu, lead (Pb), cadmium (Cd) and sodium adsorption ratio.

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In order to study the effects of foliar micronutrient application under water stress at three stages of growth on proline and carbohydrate concentrations, grain yield and yield components of sunflower (Alster cultivar), a field experiment in split plot design with three replications was conducted in 2007. Alster cultivar was considered under water stress at three stages of growth (heading, flowering and grain filling) as main plot and seven micronutrient treatments, Fe, Zn, Mn, Fe+Zn, Fe+Mn, Zn+Mn and Fe+Zn+Mn, as sub plots. Results showed, water stress at three stages of growth significantly decreased grain yield, biological yield, 1000 weight seeds, cap diameter and cap weight of sunflower (Alster cultivar). The impact of water stress was more pronounced when applied at grain filling. Use of foliar micronutrient increased grain yield in water stress. On the other hand, use of Mn foliar application had the highest positive effect on yield components and grain yield. Free proline and total soluble carbohydrate concentration were increased under water stress at all of the three stages of growth. The highest concentration of these two components was found on the flowering stage. Foliar micronutrient also increased accumulation of the two components.

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Environment pollution is an important problem in the world. In agriculture irrigation, drainage and fertilization activities cause water resource and environmental pollution by effecting on solute, nutrient and sediment transport. Combined methods of water and nutrient management could consider in pollution transport controlling that reducing runoff and deep percolation, providing opportunity for solute infiltration, reducing sediment transport even economic and easy usage. In this research, affect of two different management in irrigation (cutback and continues) and fertilization (solid and fertigation) on nutrient loss was evaluated. Comparing nitrate, phosphor and potassium loss in different management explicate cutback flow with no uniform solid distribution of fertilizer is more useful to prevent nutrient loss. Because of similar results, increasing in fertilizer distribution in furrow length and easy usage between nitrate losses in six managements, show cutback flow with three proceeding solid, fertigation and fertigation (with 1/4, 1/2 and 1/4 ratio) fertilization was recommended replacement of cutback flow with three proceeding solid fertilization.

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This study was conducted to investigate nutritional status and some quality aspects of greenhouse cucumber in Qom province. After selecting 20 greenhouses, concentrations of macro- and micronutrients as well as lead (Pb) and cadmium (Cd) in soil and plant were measured. In addition, some fruit quality attributes were determined. Phosphorus (P) and potassium (K) concentrations in soils were much higher than their critical levels. The mean concentrations of soil DTPA-extractable iron (Fe), copper (Cu), and manganese (Mn) were 12.0, 1.98, and 14.5, respectively. The mean concentration of calcium (Ca) in cucumber leaf was high while in fruit was lower compared to its sufficiency level. Most fruit samples were deficient in K, Fe, Zn, Cu, and Mn. The mean nitrate (336 mg kg-1) and Pb (0.34 mg kg-1) concentrations in cucumber fruits were higher than their acceptable levels. Ascorbic acid concentration of fruits showed positive correlation with Fe concentration. Also, fruit Mg concentration had a positive correlation with the total dissolved solids and negative correlation with fruit moisture content. The results indicated that improper nutrition management in Qom cucumber greenhouses has caused micronutrients deficiencies and high nitrate and Pb concentration, which are important to consumers' health.

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The growth and fluorescence parameters of chlorophyll in four corn hybrids including two sweet (K.S.C. 403 and K.S.C. 404) and two grain hybrids (S.C. 500 and S.C. 700) were evaluated in response to Fe and Zn nutrition in a nutrient solution culture. This study was conducted in a randomized complete block design with a factorial arrangement with three replications at the Soilless Culture Research Center (SCRC). Corn hybrids were exposed to two Fe levels (5 and 50 µM Fe in the form of FeEDTA) and two Zn levels (0 and 2 µM Zn in the form of ZnSO4). Increasing Fe concentration in the nutrient solution increased F0, Fm, and Fv/Fm values by 48, 96, and 123%, respectively. The fluorescence parameters of chlorophyll were affected by corn hybrid and there were significant differences in F0 and Fv/Fm at 1% level and Fm at 5% probability level among the studied hybrids. Iron deficiency significantly (P<0.05) reduced the root dry weight of all the studied hybrids. Zinc deficiency resulted in a significant decrease in the root dry weight of H403 and H500 hybrids while no significant decrease was found in the root dry weight of the H404 and H700 hybrids under Zn condition. The results showed that corn hybrids varied significantly in their tolerance to Fe and Zn deficiency. Based on the results of plant growth and fluorescence parameters of chlorophyll, the studied grain corn hybrids were more tolerant to Fe and Zn deficiency conditions in comparison with sweet corn hybrids. It seems fluorescence parameters of chlorophyll might be suitable parameters to screen corn hybrids in their tolerance to Zn and particularly Fe deficiency condition.

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Calcareous and gypsiferous soils are restricting factors for uptake of some plant nutrient elements and plant production. Most soils in Iran are calcareous and gypsiferous. Therefore, the aim of this study was the evaluation of calcium carbonate (Caco3) and gypsum effect on availability of some nutrients and corn growth. This study was conducted in a greenhouse at Vli-e-Asr University of Rafsanjan. Treatments were arranged in a factorial manner as a completely randomized design with three replications. Treatments were three levels of Caco3 (0, 20 and 40 g/100g soil), gypsum at three levels (0, 15 and 30 g/100g soil) and two soil textures (Sand and Silt clay loam). Results indicate that irrespective of soil texture, Caco3 application significantly decreased leaf area (by 80% and 15% for sand and silty clay loam texture, respectively), dry weight (by 80% and 15% respectively), plant height (regressed on Caco3 percentage by slopes -0.7 and -0.15 for sand and silty clay loam respectively), and shoot Fe (-9.67 and -11.3) and Zn (-0.24 and -1) uptake, but had no significant effect on shoot Cu uptake. In sandy soil, application of gypsum, significantly decreased leaf area (80%), dry weight (62%), and shoot Cu uptake (slope= -1.93), but had no significant effect on plant height and shoot Zn uptake. Gypsum application significantly reduced shoot Fe uptake (slope= -24.86) in fine textured soil, but it had no significant effect in coarse textured soil.