Iranian Journal of Soil Research
Year:2010 | Volume:24 | Issue:1|Papers Count:11

A greenhouse factorial experiment, using completely randomized design, with four replications was carried out to investigate interactive effects of Zn, Fe and Mn in various wheat organs. Treatments consisted of three Zn levels (0, 40 and 80 mg kg-1 soil) in the form of ZnSO4.7H2O, three levels of Fe (0, 15 and 30 mg kg-1 soil) in the form of Fe-EDDHA and three levels of Mn (0, 15 and 30 mg kg-1) in the form of MnSO4.7H2O. Results showed that Zn treatments had a significant effect on concentration of these elements in wheat organs. Application of Zn increased Fe concentration significantly in stems (85.2 to 99.5 mg mg kg-1) and decreased iron in roots (171.4 to159.7 mg kg-1) and clusters (56.0 to 52.6 mg kg-1) of wheat. Zinc application also decreased Mn concentration in roots (75.2 to 72.7 mg kg-1) and stems (24.4 to 20.4 mg kg-1) and increased its concentration in clusters (16.2 to 28.6 mg kg-1). Soil application of Fe reduced Zn (46.6 to 43.3 mg kg-1) and Mn (44.2 to 33.8 mg kg-1) concentrations in clusters and stems (34.4 to 24.4 mg kg-1 for Zn and 26.0 to 20.4 mg kg-1 for Mn) and increased their concentration in roots significantly. Soil application of Mn had a significant effect on Mn concentration in clusters and roots of wheat. Mn application also resulted in an increase of Zn concentration in roots (57.4 to 59.2 mg kg-1) and stems (29.0 to 31.3 mg kg-1), increase of Fe concentration in stems (142.2 to 163.9 mg kg-1) and clusters (52.0 to 55.2 mg kg-1) and reduction of Fe concentration in roots of wheat. In integrated use of these three elements, Zn movement rate to clusters was higher than Fe and Mn. Considering the higher demands of plants for Fe and Mn than Zn, higher translocation of Zn to cluster, might disturb nutrient balance in plant tissues.

In order to evaluate rock phosphate direct application as a source of phosphorus for canola, a randomized complete block experiment with 8 treatments and 3 replications was carried out at Safiabad Agricultural Research Station of Dezful on a calcareous soil. The treatments included: T1=the control; T2=triple superphosphate (80 kg/ha); T3=rock phosphate (160 kg/ha); T4=rock phosphate+organic material; T5=rock phosphate+ organic material+inoculum of phosphate solubilizing bacteria; T6=rock phosphate+sulfur+ Thiobacillus inoculum; T7=rock phosphate+sulfur+ organic materials; T8=rock phosphate+sulfur+ Thiobacillus inoculum+ organic materials. After preparing soil for cultivation plots were made measuring 3x7m followed by the application of experimental treatments as described. The major nutrients, nitrogen (as urea), potassium (as potassium sulfate) and zinc (as zinc sulfate) were applied at rates based on soil tests equally on all plots. Canola seeds were planted 20 cm apart on ridges 60 cm a part. Cultivation practices were applied uniformly in each plot during the growing season. Plants were harvested at the end of the growing season when the seed yield, straw yield, number of bushes per plot, number of pods per plant; number of seeds per pod, thousand kernel weight, the oil and protein content of seeds as well as the concentrations of phosphorus, potassium, sulfur, iron, zinc, copper, and manganese in the seeds and shoots were determined. The highest seed and straw yields were obtained with triple super phosphate (T2) which increased the seed and straw yields by 60 and 92% respectively as compared with the control. Treatment 8, rock phosphate +sulfur+organic matter+ Thiobacillus inoculum increased the seed and straw yield by 37.7 and 70 per cent respectively as compared to the control, which was the only treatment being statistically in the same category as triple superphosphate treatment but significantly different from other treatments.There were no significant treatment effects on the thousand kernel weight, number of seeds per pod, number of plants per square meter, number of pods per plant, or the protein content of the seeds. Treatment 8 increased seed oil content by 39.04% and was second only after treatment 2 with respect to improving seed oil content. As a whole treatments that contained sulfur, produced seeds with greatest percent oil which were significant in some cases. There were no significant differences with respect to the leaf and seed concentrations of nitrogen, potassium, sulfur, zinc, iron, copper and manganese among different treatments, however T8 and T2 performed superior to the other treatments with respect to the indices mentioned. T8 and T2 performed the best and were in the some statistical group with regard to significantly improving the uptake, by seeds, of nitrogen, phosphorus, potassium, sulfur, zinc, iron, copper and manganese as compared with the control. Data analysis on the trend of changes in soil available phosphorus also showed that 2 months after the application of the treatments available phosphorus reached a maximum level followed by a small decrease in every treatment and then followed a rather similar trend there after.

This experiment was carried out to determine the effect of different organic residues on canola yield (Var.PF7045/91) and soil properties from 2001 to 2002 at Safiabad Agricultural Research Center of Dezful-Iran. The experimental design was a randomized complete block as a split plot arrangement of treatments with three replications. Organic residues including: sheep manure compost, sugar cane bagasse compost, wheat straw, were as main plots and their application rates were as subplots (5, 10 and 10 t/ha), also in each replication a control plot (without residue) was included. The results showed that the addition of various organic residue especially sheep manure compost and sugar cane bagasse compost caused an increase of canola grain yield compare to the control plot. Application of organic residues resulted in about one t/ha yields increase. On the other hand, application of organic residues caused to improve of soil organic matter content and decline of soil bulk density. Application of sheep manure compost or sugar cane bagasse compost at the rate of 5 t/ha with N.P.K fertilizers, based on soil testing, are recommended.

Cadmium (Cd) is a non-essential and toxic element, without any metabolic significance, whereas zinc (Zn) is an essential element. Since both Cd and Zn have similar electronic configurations and valence, the increase of Zn in rhizosphere can adjust the toxic effects of Cd. To study the effects of Cd and Zn on growth and yield of Beta vulgaris L. cv. dark red, a greenhouse experiment was carried out in a factorial experiment with a randomized complete block design and four replications. Three levels of Cd (0, 45 and 90 mM) and three levels of Zn (0.5, 155 and 310 mM) were added to nutrient solution. The seed bed was perlite and the seeds of dark red cultivar of red beet were planted. Results showed that Cd application significantly increased Cd concentration but decreased Zn concentration in leaves and roots. Application of Cd significantly decreased photosynthesis, chlorophyll content, leaf number, leaf area and yield in plants. Application of Cd in 90 mM (Zn1Cd2) decreased dry weight, leaf area, photosynthesis, chlorophyll content and Zn concentration by 72%, 32%, 39%, 29% and 60% respectively, compared with control (Zn1Cd0). Application of Zn in nutrient solution significantly increased yield, chlorophyll content and leaf number, leaf area and also Zn concentration in leaves and roots of red beet. Application of Zn increased Cd concentration in leaves and roots of red beet. The interaction between Zn and Cd in chlorophyll content was statistically significant and application of Zn alleviated Cd toxic effect on chlorophyll degradation.

Improvement of plant nutrient uptake with biological agents, is a key factor in sustainable agriculture and can stable and increase crop yield. The objective of this study was to evaluate the effects of phosphate solubilizing microorganisms, mycorrhizal fungi and seed priming on nodulation of chickpea. The trial was set up in a factorial randomized complete block design with four replications. Treatments comprised of seed priming (Osmopriming, Hydro-priming and control), Mycorrhiza (Glomus intraradices and control) and phosphate solubilizing microorganisms (Bacillus megaterium, Aspergillus niger and control). Dry and fresh weight of root nodules and total and active number of nodules were measured. Results indicated that treatments had positive effects on most of the nodulation characteristics. All primed seed had more or equal total number of nodules compared with control. In mycorrhizal and priming interaction, treatments with PSF+ Osmo-priming and PSB+Hydro-priming had the highest total number of nodules. Among treatments, priming+PSF was found superior over other treatments in increasing nodule fresh weight. Phosphate solubilizing microorganism+priming caused the highest nodule dry weight. Results showed that chickpea nodulation characteristics can be improved by appropriate combination of biofertilizer and seed priming (PSF+Osmopriming, PSB+Hydro-priming and AM+Hydro-priming).

Application of Plant Growth Promoting Rhizobacteria (PGPR) as biofertilizers plays an important role in sustainable crop production management and yield. In this study effect of Azotobacter chroococcum, Azospirillum lipoferum, Azospirillum brasilense and Pseudomonas fluorescens inoculants on late maturity Maize (Zea mays L. ) single cross hybrids (SC700, SC 704 and a promising single cross, B73×K18) were utilized. Some morphological traits, dry matter partitioning and some of the root characteristics were recorded under greenhouse conditions. Hybrids seed were treated single inoculation by each bacterium and coinoculation by two and three bacteria inoculums combination and uninoculation treatment as control. Also plant and ear height, stem diameter, plant and above ear leaf number, leaves, stem, tassel and plant dry matter, root surface, volume, length, dry matter and above ground dry matter/root dry matter were determined. Results revealed that except for total number of leaves and above ear leaf number, other studied traits affected by experiment treatments and those interactions of hybrids and the inoculants. Likewise, there were significant interaction revealed that respectively SC704, B73 x K18 and SC700 and PGPR. Thus, three bacteria combination have highest growth promoting effect and Azotobacter chroococcum and Pseudomonas fluorescens and seed single inoculation Azotobacter chroococcum and Pseudomonas fluorescens inoculants have the most growth promoting effect respectively.

Arbuscular mycorrhizal fungi (AMF) are among the most important plant root symbiosis fungi, enhancing plant P uptake. To evaluate the role of arbuscular mycorrhizal fungi in enhancing the growth and P uptake of the medicinal plant coriander (Coriandrum sativum L.) under drought stress, this research was conducted in Iran in 2006. The experimental design was a split factorial with completely randomized block design in four replicates. The control and AM species, Glomus hoi, were assigned to the main plots and the combination of P fertilizer levels (including 0, 35 and 70 kg/ha of triple super phosphate) and the water stress treatments (including control treatment with irrigation interval after every 30mm evaporation and stress treatment with irrigation afetr every 60 mm evaporation from the pan) were factorially assigned to the subplots. AM and P fertilizer significantly increased the shoot yield, root colonization percent, root yield, essential oil percent, one thousand seed weight, shoot P content, root length and internode length of coriander. Means comparisons showed that the highest impacts upon those characteristics were achieved by using Glomus hoi and 70 kg/ha phosphorus application and the highest essential oil percent and root colonization percent were achieved with 35 kg/ha phosphorus application. Although the nondrought stress treatment significantly increased the growth of coriander, the highest root colonization percent, root length, and essential oil percent were achieved under the water stress treatment. It can be stated that AM is able to enhance the growth of coriander under drought stress through enhancing P uptake. This can have very important environmental implications through decreasing the amount of P fertilizer under control and drought stress conditions and also through enhancing the coriander resistance when subjected to the drought stress.

The border of land units influenced by human, social, economic events and natural occurrence has been changed mostly based on time and location parameters and partly unplanned. Data according to the environmental conditions are necessary for source management. As it takes a long time and expense to collect data, tools and technologies are applied so that exact and less expense might be consumed. This research focused on land use change in Karaj city, located in west of Tehran interval 1987 and 2002 with applying remote sensing technique and satellite images. Landsats 5 and 7 (ETM+) images used for this study. First the region was extracted then land units classified by supervised classification, brightness and greenness images. The result from various types of classifications compared with each other as well as ground truth, so that the settlement between supervised classifications with land use can be specified. By surveying on the images reveals that magnitude of change this metropolis like the others in the world have high rate changes in social-economic environment and land use. According to the images in 1987, the extent of built-up units includes Karaj city and suburbs and its vicinities were 6032.3 hectares and in 2002 images was 10541.12 hectares. So Karaj city converted to metropolitan and vicinities to towns and cities. The high rate growing of Karaj caused farmlands and orchards transformed to build-up lands. This conversion was happened toward south and west where the lands are more suitable for cultivation and agriculture productions. According to this research, using satellite images for interval in vast areas by various processing methods and classifications are very effective and important and mostly results coincide the facts.