Trace Metal Concentrations in the Liquid Phase of  Phosphate Rock-Treated Soils

Concentrations of potentially toxic elements were determined in the soil solution of two soils (acidic sandy and slightly acidic clay loam) treated with phosphate rocks having high Cd content in a pot experiment. Relative concentrations characterizing the mobility of metals (expressed as soil solution concentrations in percentage of their “total” amounts in the phosphate rock-treated soil) decreased with increasing phosphate rock rates in the sandy soil. Mn@Sr>Cd@Co were the most, while Pb and Cr the least mobile elements. The relative concentrations in the clay loam soil were much lower than in the sandy soil and they practically remained constant with increasing phosphate rock rates. It was concluded that in the experimental time frame the environmental risk did not increase with the increase of phosphate rock rate.

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The Effect of Phosphate Rocks on Spring Barley Shoot Yield in a Pot Trial

Agrokémia és Talajtan ◽

10.1556/agrokem.55.2006.1.21 ◽

2006 ◽

Vol 55 (1) ◽

pp. 193-202 ◽

Cited By ~ 4

Author(s):

Péter Csathó ◽

E. Osztoics ◽

J. Csillag ◽

T. Lengyel ◽

L. Gonda ◽

...

Keyword(s):

Sandy Soil ◽

Spring Barley ◽

Ammonium Citrate ◽

Acidic Ph ◽

Clay Loam ◽

Phosphate Rocks ◽

Clay Loam Soil ◽

Single Superphosphate ◽

Ammonium Lactate ◽

Loam Soil

Depending on their origin, sedimentary phosphate rocks (PRs) may differ in their P solubility, and, as a consequence, in their agronomic effectiveness. The effect of six phosphate rocks (PR) - originating from Algeria (ALG), North Florida (FLO), North Carolina (NCA), Senegal (SEN) Morocco (MOR) and Hyperphosphate (HYP) with various P solubility (evaluated by 2% formic acid, 2% citric acid, and neutral ammonium citrate) - as well as single superphosphate (SSP) and superphosphate + lime (SSP + Ca) (each P source on 4 P levels, with doses of 0, 100, 400 and 1600 mg P 2 O 5 ·kg -1 soil) on the shoot yield of tillering stage spring barley, soil available P (i.e. H 2 O, Olsen, Bray1, Lakanen-Erviö (LE) and ammonium lactate (AL) extractable P contents) were studied in pot experiments set up with acidic sandy soil (Nyírlugos, Hungary) and acidic clay loam soil (Ragály, Hungary), both with low P supplies. The average spring barley shoot yield at the beginning of shooting was 95% higher on the colloid-rich acidic (pH KCl : 4.5) clay loam soil than on the colloid-poor acidic (pH KCl : 3.8) sandy soil. The differences in the solubility of phosphate rocks showed close correlation to the differences in P responses. On both soils, the correlation between total PR-P added and P responses in spring barley shoot yield was much weaker than that between neutral ammonium citrate soluble PR-P added and P responses in spring barley shoot yield. When phosphate rocks were applied as P sources, the comparison of soil test P methods showed a different picture on the two soils. In the case of the acidic sandy soil (Nyírlugos), the strongly acid LE-P (r² = 0.83) and AL-P (r² =0.74) tests gave the highest correlation coefficients with spring barley responses to P, while on the acidic clay loam soil (Ragály) these were achieved by the Olsen-P (r² = 0.88) and Bray1-P (r² =0.88) methods.

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Effect of different environmental conditions on bacterial chemotaxis toward fungal spores

Canadian Journal of Microbiology ◽

10.1139/m93-140 ◽

1993 ◽

Vol 39 (10) ◽

pp. 922-931 ◽

Cited By ~ 16

Author(s):

Dilip K. Arora ◽

Sushma Gupta

Keyword(s):

Soil Ph ◽

Sandy Soil ◽

Sandy Loam ◽

Fungal Spores ◽

Bacterial Chemotaxis ◽

Chemotactic Response ◽

Clay Loam ◽

Clay Loam Soil ◽

Matric Potential ◽

Loam Soil

The chemotactic response of four common soil bacteria, Agrobacterium radiobacter, Bacillus subtilis, Pseudomonas fluorescens, and Xanthomonas malvacearum, was observed in natural soil to conidia of Cochliobolus sativus, chlamydospores of Fusarium oxysporum f.sp. ciceri, sclerotia of Macrophomina phaseolina, and oospores of Phytophthora drechsleri f.sp. cajani. All bacteria migrated through soil toward fungal spores. Chemical analysis of fungal exudates demonstrated the presence of various amino acids and sugars that served as chemoattractants. The effect of temperature, pH, soil water matric potential, and soil texture on bacterial chemotaxis toward fungal spores was also investigated. In general, the response of bacteria to different types of fungal spores was significantly greater (P = 0.05) at higher water matric potential (0 and −5 kPa) than at lower soil water potential (−10 and −20 kPa). The chemotactic response was greatest in sandy soil, followed by sandy loam and clay loam soil. High temperature (40 °C) was not favourable for bacterial chemotaxis. The chemotactic response decreased by 4 to 28 times when soil pH decreased from 7 to 5 or increased from 7 to 9. The relative concentration response of the exudate of fungal spores and the motility or chemotaxis of bacteria were assessed. A significant positive correlation (P = 0.05; r = 0.89–0.92) was recorded between motility and relative concentrations of exudate. The swimming speed and tumbling frequency of Pseudomonas fluorescens cells was observed at different pH values and temperatures. The swimming speed of bacteria increased with increasing temperature, but decreased with an increase in pH from 5 to 7. The tumbling frequency had a sharp peak at 30 °C and pH 7. Bacteria were able to stimulate the release of exudate from the fungal spores. The amount of exudation was also affected by temperature, pH, and soil texture. A positive significant correlation (P = 0.05; r = 0.79–0.85) was recorded between exudation and a progressive increase in temperature. The amount of exudation also increased with an increase in soil pH from 5 to 8, but further increases in pH decreased the rate of exudation. In general, fungal spores exuded the greatest amounts of carbon compounds in sandy soil, followed by sandy loam and clay loam soil. Exudation in sandy soil was often greatest in the presence of A. radiobacter cells, while the greatest exudation in sandy loam and clay loam soils was induced by B. subtilis cells.Key words: chemotaxis, chemoattractants, fungal spores, motility.

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Efficiency of Prepared Chelate Fertilizer From Humic Acid in Reducing Ammonia Volatilization From Urea Fertilizer

Basrah Journal of Agricultural Sciences ◽

10.37077/25200860.2019.271 ◽

2019 ◽

Vol 32 ◽

pp. 231-245

Author(s):

Ola D. AbdulSayed ◽

Hayfaa J.H. Al-Tameemi

Keyword(s):

Humic Acid ◽

Sandy Soil ◽

Incubation Time ◽

Ammonia Volatilization ◽

Plant Residue ◽

Cow Manure ◽

Clay Loam ◽

Clay Loam Soil ◽

Urea Fertilizer ◽

Loam Soil

Composted cow manure sample was collected from filed of college of Agriculture, University of Basrah. Its properties were identified. Humic acid was extracted from cow manure and diagnosed according to elemental analysis (CHN), spectral study (E4/E6), infra-red spectrum (IR), in addition to chemical composition of functional groups. Two types of humic acid were prepared, one of them humic acid with fermented plant residue (HA1-N) and other humic acid with zeolite (HA2-N). A laboratory experiment was carried out to study the amount of ammonia volatile from two prepared chelate fertilizers (HA1-N and HA2-N) and urea fertilizer by incubation two types of soils (sandy soil and clay loam soil) at 35°C with four rates of nitrogen (0, 125, 250 and 500 mg N kg-1 soil) and with five incubation time (3, 6, 12, 24 and 48 days). The study found that increasing rate of nitrogen and incubation time increased ammonia volatilization, and the highest value was at the rate 500 mg N kg-1 soil and at 48 days of incubation to reach a 21.427 and 9.736 mg N-NH3 Kg-1 soil for sandy soil and clay loam soil, respectively. Application of two prepared chelate fertilizers (HA1-N and HA2-N) at rate 500 mg N Kg -1 reduced ammonia volatilization to 99.30 % and 98.62 % for sandy soil and 98.96 % and 97.77 % for clay loam soil comparing with urea fertilizer . Fertilizers were took the following order in reducing ammonia volatilization : HA1-N > HA2-N > Urea.

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L’EFFET DU TEMPS DE L’ECHANTILLONNAGE ET DE L’HETEROGENEITE DU CHAMP SUR LES ANALYSES DE FERTILITE DU SOL

Canadian Journal of Soil Science ◽

10.4141/cjss78-057 ◽

1978 ◽

Vol 58 (4) ◽

pp. 511-520

Author(s):

Y. A. MARTEL ◽

J. ZIZKA

Keyword(s):

Sandy Soil ◽

Cultural Practice ◽

Sampling Time ◽

The Other ◽

Clay Loam ◽

Clay Loam Soil ◽

Surface Drainage ◽

Coefficients Of Variation ◽

Loam Soil ◽

Field Heterogeneity

The objective of this work was to determine the effect of sampling time and field heterogeneity on the soil fertility tests (pH, organic matter, N, P, K, Ca, Mg). The sampling on Ap horizons was repeated in May, July and October of 1976 at 25 locations of a clay loam soil (Kamouraska Series) and a sandy soil (Vien Series). The results indicated that the coefficients of variation were lower than 7% for the pH analyses but exceeded 30% for the other analyses. For the latter, sampling time showed a significant decrease in the P, K and Mg values from May to October on the sandy soil but showed no effect on the clay loam soil. Field heterogeneity was found to be a greater factor of variation than sampling time. It explained an average of 26% of the variation obtained on the sandy soil and 74% on the clay loam soil where the cultural practice of raising the center of the field, for better surface drainage, caused great variations in the depth of the Ap horizons in relation to the width of the field.

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Effect The Treatments of Biofertilizer and Mineral Fertilizer on Content of N P K of Soil Cultivated With Crop Corn (Zea Mays L).

Al-Qadisiyah Journal For Agriculture Sciences (QJAS) (P-ISSN 2077-5822 E-ISSN 2617-1479) ◽

10.33794/qjas.vol9.iss2.89 ◽

2019 ◽

Vol 9 (2) ◽

pp. 247-256

Author(s):

Mohammed Aajmi Salman ◽

Jawad A. Kamal Al-Shibani

Keyword(s):

Zea Mays ◽

Zea Mays L ◽

Mineral Fertilizer ◽

Silty Clay ◽

Clay Loam ◽

Potassium Fertilizer ◽

Clay Loam Soil ◽

Silty Clay Loam ◽

Fall Season ◽

Loam Soil

Beneficial microorganisms play a key role in the availability of ions minerals in the soil and use Randomized Complete Block Desing ( R.C.B.D ). The objective of this paper to the study effect of the of biofertilizer and miniral treatments on availability of NPK for crop corn zea mays L.Two types of biofertilizer are Bacterial Bacillus subtilis and Fungal Trichoderma harianum. Three levels of potassium fertilizer are (2.9533, 0.4000 and 2.9533). A field experiment in fall season of 2018 Has been conducted in silty clay loam soil. The experimental Results indicated that Bacillus and Trichoderma inoculation separately or together Have made a significant effect to increase in the availability of N P K in the soil compare to other treatments. The grain yield is where (2.9533, 0.4000 and 2.9533) of bacterial and fungal bio-fertilizer and potassium fertilizers respectively as compared to the control.

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