shahrzad kabirinejad; mahmoud kalbasi; amir khoshgoftar manesh; M. Hoodaji; Majid Afyuni
Abstract
Introduction: Preceding crops as a source of organic matter are an important source of micronutrient and can play an important role in the soil fertility and the micronutrients cycle of soil. In addition to the role of the organic matter in increasing the concentration of micronutrients in soil solution, ...
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Introduction: Preceding crops as a source of organic matter are an important source of micronutrient and can play an important role in the soil fertility and the micronutrients cycle of soil. In addition to the role of the organic matter in increasing the concentration of micronutrients in soil solution, attention also should be paid to the role of the kind and the quantity of the root’s exudates that are released in response to the incorporation of different plant residues in the rhizosphere. Present research was conducted with the objective of studying the effect of the kind of preceding crops: Trifolium (Trifolium pretense L), Sofflower (Carthamus tinectirus L), Sorghum (Sorghum bicolor L), Sunflower (Heliantus annus L) and control (fallow) on the chemical forms of copper in the wheat rhizosphere and the bulk soil and Cu uptake by wheat and also investigating the correlation between the fractions of Cu in soil and Cu uptake in wheat.
Materials and Methods: The present research was conducted as split plot in a Randomized Complete Block design (RCBD) with 3 replications and 5 treatments, in field conditions. In the beginning, the preceding crops were cultivated in the experimental plots and after ending growth, preceding crops were harvested. Then the wheat was cultivated in the experimental plots. Finally, after harvesting the wheat, soil samples were collected from the two parts of the root zone (the wheat rhizosphere and the bulk soil). The soil samples were air dried ground and passed through a 2-mm sieve and stored for chemical analysis. Soil pH (in the soil saturation extract) and organic matter (Walkley–Black wet digestion) were measured in standard methods (1). The Total Organic Carbon (TOC) was measured by Analyzer (Primacs SLC TOC Analyzer (CS22), Netherlands). The available Cu in soil was extracted by DTPA and determined using atomic absorption spectroscopy (2). The fractionation of soil Cu was carried out using the MSEP method (3).
Results and Discussion: The results showed that the preceding crops significantly decreased soil pH, also significantly increased the DOC and DTPA-extractable Cu.These changes were higher in the Trifolium preceding treatment in the rhizosphere soil. Also, the preceding crops significantly decreased Carbonate -Cuand Residual-Cu fractions in the wheat rhizosphere compared with the bulk soil. The preceding crops (except Trifolium) significantly increased Oxide-Cu fraction. The soil Oxide- Cu fraction was higher in the rhizosphere in comparison with the bulk soil. The preceding crops increased the Organic-Cu in both the wheat rhizosphere and the bulk soil and it was higher in Trifolium treatment. The preceding crops increased Cu uptake by wheat and Organic-Cu positively correlated with Cu uptake by wheat.
Conclusion: The Organic-Cu fraction increased in the rhizosphere compared with the bulk soil, whereas Oxide- Cu, Carbonate–Cu and Residual-Cu fractions decreased. According to the results, the observed increase in the copper concentration of organic fraction in the rhizosphere was due to the decrease in the copper concentration of carbonate, oxide and residual fractions. In fact, the main process is the transmission of copper from carbonate, oxide and residual fractions to another fraction. Also, the results showed that the root exudates of the preceding crops and wheat affected the different forms of copper in the soil solid phase. Furthermore, the results of copper forms correlation analysis with Cu uptake by wheat showed that the Organic-Cu fraction had more important role in supplying copper was needed for wheat. Therefore, the preceding crops increased the copper concentration of organic fraction in the rhizosphere compared with the bulk soil, and these changes are associated with increasing the amount of copper uptake in wheat.
S.S. Tabatabaee; A. Razazi; A. Khoshgoftar Manesh; N. Khodaeian; Z. Mehrabi; E. Asgari; Sh. Fathian; F. Ramezanzadeh
Abstract
Abstract
A hydroponics experiment was conducted to compare effect of Fe-deficiency on concentration, uptake, translocation of Fe, Zn, Mn in some plants. A completely randomized block design in triplicates was conducted in research greenhouse. Seven plants with different Fe-efficiency contained two bread ...
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Abstract
A hydroponics experiment was conducted to compare effect of Fe-deficiency on concentration, uptake, translocation of Fe, Zn, Mn in some plants. A completely randomized block design in triplicates was conducted in research greenhouse. Seven plants with different Fe-efficiency contained two bread wheat genotypes (Triticum aestivium L. CVs. Backcross Roshan and Qods), triticale (X. Triticosecale Cv eleanor), dent corn (Zea Mays L. CV. S.C704) and two safflower (Carthamus tinctorius L. CVs Arak2811 and Koose) were grown in a nutrient solution at two Fe levels of 5 and 50 µM Fe EDTA. The most tolerant and the most sensitive of plants to Fe-deficiency were bread wheat (Qods genotype) with 125% Fe-efficiency and safflower (Arak2811) with 3.5% Fe-efficiency, respectively. A significant and positive correlation was found between the Fe-efficiency and Zn, Fe and Mn contents and root to shoot translocation of Fe among the studied crops. Large variation was found among the studied crops in shoot and root Zn, Fe and Mn content. The Qods and cross back Roshan wheat genotypes accumulated greater Zn, Fe and Mn in their shoots compared to other genotypes. Higher uptake and root to shoot translocation of microelements in the Fe-efficiency genotypes is an important aspect for biofertilization programs with the aim of improving crop quality.
Keywords: Hydroponic Culture, Iron deficient, Fe-efficiency, Micronutrient, Uptake, Translocation of micronutrient
A.H. Khoshgoftar Manesh; E.S. Razizadeh; H.R. Eshghizadeh; Gh.R. Savaghebi; A. Sadrearhami; D. Afuni
Abstract
Abstract
This study was conducted at Rudasht Research Farm in Isfahan to evaluate tolerance to zinc (Zn) deficiency of 30 spring wheat genotypes, using split plots in a randomized complete blocks design with triplications. Main plot consisted of two Zn levels (Zero and 80 kg Zn ha-1 applied as zinc ...
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Abstract
This study was conducted at Rudasht Research Farm in Isfahan to evaluate tolerance to zinc (Zn) deficiency of 30 spring wheat genotypes, using split plots in a randomized complete blocks design with triplications. Main plot consisted of two Zn levels (Zero and 80 kg Zn ha-1 applied as zinc sulfate at planting). The results of ANOVA as well as correlations between tolerance and susceptibility indices to Zn deficiency stress and grain yield indicated that MP, GMP and STI were the most suitable indices for identifying and selecting Zn-deficiency tolerant wheat genotypes. Both at with and without added Zn treatments, grain yield had significant positive correlation with MP, GMP and STI. The STI could separate the studied wheat genotypes in different groups based on both their response to fertilization and grain yield potential. Therefore, the STI was the best index to identify Zn deficiency tolerant genotypes. Based on three indices, Ghods and Falat genotypes were the most tolerant and sensitive genotypes to Zn deficiency, respectively.
Keywords: Stress indicator, Wheat, Zinc efficiency, Tolerance
F. Khayamim; H. Khademi; A. Khoshgoftar manesh; Sh. Ayoubi
Abstract
Abstract
Mineral weathering is a major source of most essential nutrients including potassium. It is well known that potassium plays an important role in improving the quality of agricultural products and micaceous minerals, as the major source of potassium, are abundant in Iranian soils. No information ...
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Abstract
Mineral weathering is a major source of most essential nutrients including potassium. It is well known that potassium plays an important role in improving the quality of agricultural products and micaceous minerals, as the major source of potassium, are abundant in Iranian soils. No information is available on the role of micaceous minerals in supplying K to barley as the second major crop in Iran. The objective of this research was to demonstrate the ability of barley (Hordeum vulgare L.) to take up structural potassium from muscovite and phlogopite. The experiment was carried out in a completely randomized design with factorial combinations and three replicates. Culture medium was a mixture of quartz sand (as filling material) and K-bearing minerals including muscovite or phlogopite. Pots were irrigated with different nutrient solutions (+K and -K) during a period of four months. Barley Govhar cultivar was used which is widely cultivated in the Isfahan province. At the end of experiment, shoots and roots were separated and plant samples were prepared with dry ashing method and their K content was determined with flame photometer. In K-free treatments, total plant K uptake was significantly higher in phlogopite treated medium as compared to muscovite. No significant difference was found between control and muscovite amended treatment under K-free solution. In pots amended with phlogopite, K concentration was in sufficient limit, even under K-free nutrient solution. This indicates the importance of the type of micaceous minerals in plant K availability, particularly in soils where minerals structural K is the only source of K supply.
Key words: Muscovite, Phlogopite, Barley, Rhizospheric effections, Potassium release
