Kilogram Of Soil Research Articles

Effect of cadmium on sorghum root colonization by glomeral fungi and its impact on total and easily extractable glomalin production.

Glomalin is a specific glycoprotein compound synthesized by glomeral fungi and its amount varies according to soil conditions. Due to the symbiosis of these fungi with a multitude of plants, a remarkable amount of glomalin is produced inside the hypha wall of these fungi. Furthermore, while increasing the symbiosis stability, glomalin plays a critical role in reducing the availability of potentially toxic elements (PTEs) through their fixation. In this regard, soil contamination with PTEs such as cadmium (Cd) affects the glomalin production of mycorrhiza fungi. In order to investigate the effect of different levels of Cd on glomalin production of three species of arbuscular mycorrhiza fungi in the presence of sorghum, a greenhouse experiment was conducted in a completely randomized design with factorial arrangement and three repetitions. Factors include four levels of Cd (0, 5, 10, 20 milligrams per kilogram of soil) and second factor included these three types of mycorrhiza: Funneliformis mosseae (FM), Rhizophagus intraradices (RI), and Claroideoglomus etunicatum (CE). The results of this study showed that when increasing soil Cd concentration, shoot dry weight, root colonization percentage, total and easily extractable glomalin decreased while leaf proline concentration, shoot, and root Cd concentration increased. The presence of mycorrhiza in comparison with the control increased the dry weight of shoots and plant height. The results showed that mycorrhizal treatments increased total and easily extractable glomalin compared to the absence of mycorrhiza. Also, the highest amount of glomalin production was observed in two species of FM and CE. Complexation of Cd by total glomalin and easily extractable glomalin was higher in two species of FM and CE rather than RI. The results showed that the use of three species of mycorrhizae reduced the adverse effects of high levels of Cd. Also, the concentration of leaf proline, soluble sugars, shoot, and root Cd concentration was higher in presence of mycorrhizal fungal species than in plant not inoculated with mycorrhizal fungal species. This increase was significant in both FM and CE species. Finally, a notable positive correlation was also observed between glomalin measured by Bradford method and percentage of root colonization.

Understanding the effect of oil on phytoremediation of PCB co-contamination in transformer oil using Chromolaena odorata

Greenhouse assessment of the effect of oil on Chromolaena odorata ability to remove PCB from soil treated with transformer oil co-contaminated with Aroclor 1260 was done. Plants were transplanted into one kilogram of soil contained in 1 L pots differently containing 100, 200, and 500 ml of transformer oil (T/O), co-contaminated with 100 ppm of Aroclor. Treatments were done in two microcosms; direct contamination and soil cultured method. Measured plant growth parameters showed that C. odorata growth was affected by the different concentrations of oil. Inhibition of plant growth by oil increased with concentrations. At the end of six weeks, plant growth was affected in T/O amended soil. Plants size was increased by 1.4, 0.46 and −1.0% in direct treatment and 17.01, 6.09 and 1.08% in soil culture at the 100, 200 and 500 ppm respectively. Untreated control showed a 43.07% increase. Slight PCB recovery was observed in root tissues of C. odorata but soil PCB was reduced by 66.6, 53.2, 41.5% and 77.3, 74.7, 58.8% at both treatments in their respective concentrations of oil. However, unplanted control was reduced by 21.4 and 16.7% in the two treatments at 66,000 ppm of oil. This study has shown that with improved agronomic practices, there is a possibility of phytoremediation of soil PCB from PCB contained transformer oil contaminated soil using Chromolaena odorata, hence it should be optimized in the field.

Effect of organic manure on growth and proximate composition of Treculia africana var. deene seedlings

A study on the effect of organic manure on seedling growth and proximate composition of T. africana seedlings was conducted to influence the growth and improve the nutritive quality of the plant as an alternative source of feed for dry season feeding. Three months old seedlings of T. africana were transplanted on the field containing samples of organic manure (poultry and cow dung) mix with top soil in a ratio of one kilogram of soil to 25 g of manure and a control (without manure) in a Randomized Complete Block Design which was replicated thrice. The seedlings were assessed for plant height, number of foliage, collar diameter and number of branches. Samples of the seedlings foliage were collected across the treatments and analyzed for proximate composition after the eighth week of transplanting. Seedlings under cow dung application recorded a significantly (P>0.05) higher values for number o foliage per plant (21.82), plant height (66.58 cm), collar diameter (12.96 mm) and number of branches (4.20) at 8 weeks after planting (WAP), followed by seedlings to which poultry manure was applied and lastly by the control. Proximate composition showed that the dry matter (DM) content values of the samples were high which ranged from 894.60- 896.30 g/ kg DM (p<0.05). The crude protein (CP) content followed the same trend as the DM with its values ranging between 143.6 and 149.30 g/kg DM (p<0.05) and the ether extract (EE) values ranging between 22.20 and 23.50 g/kg DM (p<U.05) for the samples collected respectively. The ash content did not vary significantly between the different manure and the control. The Crude fibre was quite significantly (p<0.05) low in the samples ranging from 162.10 and 166.70 g/kg DM. This study showed that cow dung is the most suitable manure for T. Africana seedlings in terms of mineralization and it is relatively fast when compared with poultry manure, and the application of poultry manure has also it has positively influence the growth and development of T. Africana seedlings while poultry manure increased the digestible fraction (i.e crude protein) of the plant.

Zinc-cadmium interactions instigated antagonistic alterations in lipid peroxidation, ascorbate peroxidase activity and chlorophyll synthesis in Phaseolus vulgaris leaves

Understanding the functional role of zinc interaction during cadmium-induced oxidative changes and photosynthetic response in the leaves of Phaseolus vulgaris plant was central in this study, as driven by Box-Behnken Design (BBD), a typified Response Surface Methodology (RSM). The design considered 0–50 mg each of CdCl2 and ZnCl2 per kilogram of soil contaminated daily in a time-dependent process, and for the post-germination of P. vulgaris seeds, malondialdehyde (MDA) level, ascorbate peroxidase (APX) activity and total chlorophyll content (TCC) were evaluated in seventeen “experimental runs” for nine weeks of study. The findings from the RSM-BBD study indicated significant generation (p<0.05) of response surface models with 87.08, 97.78 and 98.10 % r-squared values for MDA level, APX activity and TCC respectively, and these were validated in the laboratory through numerical optimization approach (NOA). The study also revealed that increasing dose of Cd significantly inhibited (p<0.05) the synthesis of TCC in plant leaves, which was significantly relieved (p<0.05) by increasing dose of Zn compound. The significant increase (p<0.05) in MDA levels, as a biomarker of Cd-induced oxidative stress, was ameliorated by marked increase in Zn concentration at p<0.05. The interaction also showed that the Cd-instigated inhibition of APX activity was significantly improved by increasing levels of Zn compound. Therefore, the present study resolved the controversies associated with previous conventional studies by establishing antagonistic effects from Zn-Cd interaction for the assessed responses in the leaves of P. vulgaris by RSM-BBD at defined optimal conditions.

Influence of Induced Soil Compaction on the Growth, the Yield and the Soil Loss Resulting from the Groundnut Harvesting

The research was conducted to study the growth and the yield of the groundnut plant and to quantify the soil loss after groundnut harvesting as influenced by induced soil compaction. A ten kilogram of soil was packed in the pots with an initial bulk density of 1.05 Mg m-3, then it were compressed to1.57, 1.72, 1.88, 2.04, and 2.42 Mg m-3. The research was conducted in a completely randomized design with three replications. Groundnut seeds were sown in pots and the plant growth data were collected in a 2-week interval while force and energy of harvesting and soil loss due to groundnut harvesting were determined at 12 weeks after sowing. Data were analyzed using ANOVA and Fishers LSD at P= 0.05. Soil compacted to1.88 Mgm-3 produced more taller plant, more higher number of leaves and branches than control. Soil compaction significantly reduced the number of pods, roots, and fresh root weight compared to control. Bulk density (2.04 Mgm-3) required a significantly higher force (42.47 N) and energy (45.73 J) in harvesting than control and other compaction levels. Soil loss due to the groundnut harvesting increased (13- 42%) in all compaction levels although statistically not different. Soil compaction beyond 1.88 Mg m-3 could affect the growth and the yield of groundnut and could increase the soil loss at harvesting.

Eco-friendly Management of Bacterial Wilt in Tomato Using Dried Powder of the Wild Arid-Land Medicinal Shrub Rhazya stricta.

Bacterial wilt (BW) disease caused by Ralstonia solanacearum species complex is a devastating plant disease that inflicts heavy losses to the large number of economic host plants it infects. In this study, the potential of dried powder of the arid-land medicinal shrub Rhazya stricta to control BW of tomato was explored. Both, in vitro and in planta studies were conducted, using different concentrations of dried powder of plant parts, and applied (surface mulched or mixed) to infested soil at 0, 10, and 20 days before transplanting (DBT). Aqueous extract of leaves (16% w/v) was found to be as effective as streptomycin (100 ppm) in inhibiting the in vitro growth of R. solanacearum. As evident from the scanning electron micrograph, 16% aqueous extract of leaves produced severe morphological changes, such as rupture of the bacterial cell walls. Results from the greenhouse experiments demonstrated that the higher powder dose (succulent shoot), namely, 30 g/kg of soil mixed with infested soil 20 DBT, was found to be the most effective in controlling BW. It increased root length (cm), shoot length (cm), and plant fresh biomass (g) by 55, 42, and 40%, respectively, over control plants. Mixing of plant powder with the artificially infested (35 ml of 108 CFU/ml per kilogram of soil) pot soil was better than surface mulching. The 30 g/kg of soil dose mixed with soil increased root length (cm), shoot length (cm), and plant fresh biomass (g) of treated plants by 67, 36, and 46%, respectively, over control plants. A 37% decrease in disease severity over the control was observed with drench application of 30 g of powder per kilogram of soil applied once at 20 DBT. Our results indicated that the dried powder (30 g/kg of soil) of leaves or succulent shoots of R. stricta, thoroughly mixed with soil, 20 DBT, could act as an effective control method against BW.

Geotechnical characterisation of two new low-fidelity lunar regolith analogues (UoM-B and UoM-W) for use in large-scale engineering experiments

Engineering experiments regarding excavation, sampling, or mobility for rocky planetary surface exploration (Moon, asteroids, the moons of Mars, Mars) often require large test beds filled with hundreds of kilograms of soil. Specifically engineered regolith simulants are costly and often not available in large enough quantities due to limited production rates. The use of low-fidelity analogues is reasonable, but their geotechnical properties have to be reported in order to be able to calculate excavation and traction forces, as well as to make results comparable and repeatable. This necessary characterisation step is often overlooked in studies regarding regolith handling and excavation. Two readily available low-fidelity analogue materials, we term UoM-B and UoM-W, have been identified and their geotechnical characteristics investigated. The chemical composition, particle morphology, particle size distribution, specific gravity, maximum and minimum densities, and shear strength parameters have been determined. These parameters can be seen as standard metrics in the characterisation of planetary regolith simulants or analogues. The obtained results are compared to values known for five relevant lunar regolith simulants and data from Apollo lunar regolith samples. Although the materials are fundamentally chemically different to Apollo lunar regolith, both materials showed promising characteristics for use as low-fidelity analogues in large-scale engineering experiments; their mechanical properties, crucial for engineering experiments, were found to be similar to lunar regolith and its simulants.

Study of Changes in Activity of Wheat Antioxidant Enzymes under Stress Residue of Imazethapyr Herbicide

In order to investigate physiological and biochemical changes of wheat under stress residue of Imazethapyr herbicide (Imazethapyr), an experiment was conducted in a completely randomized design with four replications in greenhouse conditions at university of Mohaghegh Ardebili. The treatments consisted of five dose levels of herbicide Imazethapyr (0, 0.011, 0.022, 0.033 and 0.044 micrograms of herbicide) per kilogram of soil. The analysis of variance showed that the content of the main and auxiliary pigments of leaf, proline, sugar content, protein, activity of catalase enzymes, peroxidase, polyphenol oxidase, root and shoot dry weight were significantly affected by herbicide. The results showed the Imazethapyr herbicide stopped the production of valine leucine and isoleucine amino acids. As a result, the rapid reduction in the volume of these amino acids led to a reduction in protein synthesis in wheat plant. Therefore, the application of doses of 0.011, 0.022, 0.033 and 0.044 micrograms of herbicides decreased 14, 26, 44 and 47 percent of leaf protein content, respectively, compared with control treatment. Further, theapplication of these doses resulted in the reduction of 2.8, 5, 27 and 64% of activity of catalase enzyme, 3.5, 39, 49 and 52% peroxidase enzyme activity and 13, 24, 35 and 46% activity of polyphenol oxidase enzyme, compared with control treatment. The results revealed that Imazethapyr herbicide activates wheat antioxidant enzymes to reduce plant tolerance from damage caused by herbicide residues; therefore, it can be used as a marker or index of herbicide damage rate in physiological research.

ASSESSMENT OF PHOSPHORUS AVAILABILITY FROM UNREACTIVE TOGO PHOSPHATE ROCK BY LEGUME AND CEREAL CROPS IN TWO GHANAIAN SOILS

Purpose: In recent years, phosphate rock (PR) for direct application has been tested in tropical acid soils as a potential alternative to conventional water-soluble P fertilizers like Single Superphosphate (SSP) and Triple Superphosphate (TSP). However, direct application of PR with low reactivity does not always give satisfactory results. Legume and cereal crops represent a strategy that can be used to solubilize P from some of these unreactive PRs. The objective of this study was to assess the availability of P from unreactive Togo Phosphate Rock (TPR) relative to TSP by six (6) crop species in two Ghanaian soils.&#x0D; Methodology: The study was conducted in the greenhouse of the Crop Science Department, University of Ghana. Three P rates, 0mg, 50mg and 100mg P of TPR and TSP were applied to a kilogram of soil per pot in the two soil series. Randomized Complete Block Design was used to do the analyses.&#x0D; Results/Findings: Application of TSP resulted in higher dry matter and P uptake irrespective of the soil type. Among the legumes, cowpea gave the highest dry matter yield. Fairly, a similar trend was obtained with the application of TPR. Among the cereals, the average P uptake by sorghum from TPR was the highest, followed by maize and millet in the Nzema soil. In the Adenta series, P uptake by maize was the highest, followed by sorghum and millet. Phosphorus (P) uptake by the cereals from TPR was generally better in the Adenta than the Nzema soil.&#x0D; Unique contribution to theories, practice and policy: Results show increasing the rate of TPR to 100mg P/pot resulted in an increase in dry matter yield and P uptake in both soils, but was inferior to 100mg P/pot TSP application. Consequently, the rate of application of TPR should always be high if farmers want the best from their investments. Again, the low relative agronomic effectiveness of TPR for all the crops, proved the low reactivity of the material and its subsequent low performance compared with the water-soluble P. The low reactivity and the high molar mass of PO43-/CO32- of the TPR will always make it difficult for P to be made available from the TPR despite the acidity of the soil, the high density of the crops and the ability of the tested crops to exude organic acids, which facilitate phosphorus availability from TPR, therefore making TPR unsuitable for direct application.

Effect of levels of biochar and FYM on physico-chemical properties, nutrients release and carbon dioxide evolution from the soil

To know the dissolution and release of nutrients from biochar and FYM, an incubation study was conducted during 2018 in College of Agriculture, using sandy loam with acidic pH (5.88) soil collected from Zonal Agricultural and Horticultural Research Station, Navile, Shivamogga. Two kilo gram of soil was filled in separate plastic boxes (2 kg capacity) and treatments imposed as per the treatments details (T1: Control (without biochar and FYM), T2: FYM @ 5 t ha-1, T3: FYM @ 10 t ha-1, T4: Biochar @ 2 t ha-1, T5: Biochar @ 4 t ha-1, T6: Biochar @ 6 t ha-1, T7: Biochar @ 8 t ha-1) and replicated thrice and was laid out in a completely randomized block design (CRBD). results revealed that, application of different levels of biochar increased the pH and EC of soil over control and FYM levels applied treatments, the greater increase of pH (6.20) and EC (0.25 dS m-1) was noticed with the application of CS-biochar @ 8 t ha-1 at 120 DAI. Available nitrogen and potassium showed a gradual increase throughout incubation. Significantly, higher available nitrogen (330.26 kg ha-1) and available potassium (229.95 kg ha-1) were registered in the treatment T7 (CS-biochar @ 8 t ha-1) at 120 DAI. However, available phosphorus content in the soil gradually increased up to 60 days of incubation and slightly decreased afterward. Secondary nutrients gradually increased over an increasing incubation period. Significantly, higher exchangeable Ca (3.64 cmol (p+) kg-1) and Mg (2.57 cmol (p+) kg-1) was recorded in the treatment T7 (CS-biochar @ 8 t ha-1). However, significantly higher available S (12.5 mg kg-1) was registered in the treatment T3 (FYM @ 10 t ha-1) at 120 DAI. Similarly, DTPA extractable micronutrients significantly, higher Fe (31.69 mg kg-1), Mn (1.24 mg kg-1), Zn (0.58 mg kg-1) and Cu (0.52 mg kg-1) was recorded in the treatment T7 (CS-biochar @ 8 t ha-1). Application of biochar and FYM levels significantly influenced the CO2 evolution as compared to control. At 60, 90 and 120 DAI, significantly maximum CO2 evolution was noticed in the biochar @ 8 t ha-1 treatment. In general, the maximum CO2 evolution increased with the increasing incubation period and levels of biochar.

Effect of Oil on Phytoremediation of PCB Co-Contamination in Transformer Oil Using Chromolaena odorata

Greenhouse assessment of the effect of oil on Chromolaena odorata ability to remove PCB from soil treated with transformer oil co-contaminated with Aroclor 1260 was done. Method: Plants were transplanted into one kilogram of soil contained in 1L pots differently containing 100, 200, and 500 ml of transformer oil (T/O), co-contaminated with 100 ppm of Aroclor. Treatments were done in two microcosms; direct contamination and soil cultured method. Measured plant growth parameters showed that C. odorata growth was affected by the different concentrations of oil. Inhibition of plant growth by oil increased with concentrations. Results: At the end of six weeks, plant growth was affected in T/O amended soil. Plants size was increased by 1.4, 0.46 and -1.0% in direct treatment and 17.01, 6.09 and 1.08% in soil culture at the 100, 200 and 500 ppm respectively. Untreated control showed a 43.07% increase. Slight PCB recovery was observed in root tissues of C. odorata but soil PCB was reduced by 66.6%, 53.2%, 41.5% and 77.3%, 74.7%, 58.8% at both treatments in their respective concentrations of oil. However, unplanted control was reduced by 21.4% and 16.7% in the two treatments at 100 ppm of oil. Conclusion: This study has shown that with improved agronomic practices, there is a possibility of phytoremediation of soil PCB from PCB contained transformer oil contaminated soil using Chromolaena odorata, hence it should be optimized in the field.

Pengaruh Kompos dan PGPR (Plant Growth Promoting Rhizobacteria) Pada Lahan Kering Terhadap Produksi Sawi (Brassica rapa L.)

The increasing of demand for agricultural product and the narrowing of fields where fields are currently being prioritized for cultivating food crops forcing them to take and use dry land. Problem happened by conducting agricultural activities on dry land such as limited water availability, low microorganism population and low nutrient avaibility. Water avaibility on dry land can be optimized by providing compost and PGPR. The productivity of Sawi nauli varieties according to the minister of agriculture decision (2009) that 37-39 tons/ha with a population per hectare are 93.000 plants. This purpose of this study is to determine the effect of compost and PGPR on dry land about pakchoy productivity. This study also used factorial completely randomized design and replicated 3 times. The design of two treatments are: The first: compost which consists of 4 levels with a dose of 5 kilograms of soil, 4900 grams of soil with 100 grams of compost, 4800 grams of soil with 200 grams of compost, 4700 grams of soil with 300 grams of compost. For the second factor is PGPR which consists of 4 levels with a dose of 0 milligrams/plant, 100 milligrams/plant, 200 milligram/plant and 300 milligram/plant. The data obtained were analyzed by using analysis of variance (ANOVA). Then, the results obtained from the ANOVA test were followed by the Standart Error Mean (SEM). Based on the results of the study it is known that there are influences from each single factor and combination of treatments. Compost treatment showed significantly different results on variable number of leaves, number of leaf chlorophyll and dry weight of plants. Whereas there is a very significant effect on plant height and plant fresh weight. On a single factor PGPR showed no significant results on variable plant height, number of leaf chlorophyll, but showed a significant effect on variable number of leaves, plant fresh weight and plant dry weight. The combination of compost and PGPR treatment showed no significant results on variable plant height, number of leaves, number of leaf chlorophyll, and plant dry weight. The treatment combination treatment showed a significant effect on the fresh weight variable of the plant

Effect of polymaleic acid on saline sodic soils

Saline-sodic soils in Middle Awash Valley area of Ethiopia have very high soluble sodium content and exchangeable sodium percentage (ESP). Leaching soluble salts with water alone could not fasten reclamation of these soils. Because all pore spaces of the soil were already sealed off with precipitated soluble salts; which retarded percolation of leaching water to the soil. Hence, Polymaleic acid was tested under controlled pot leaching under laboratory condition. The treatments were control (leaching with water only), 10, 20, 30 and 40ml polymaleic acid per kilogram of soil. Each treatment was replicated four times. As a result of leaching and polymaleic acid application to the saline - sodic soil, the ECe of the soil was was drastically reduced as the rate of polymaleic acid rate was increased. At the end of leaching, soluble cation and anions were also drastically decreased as compared to the control treatment. Hence, polymaleic acid soil conditioner could be used as an amendment for reclamation of high saline - sodic soils.

Assessing the effects of land use change from rice to vegetable on soil structural quality using X-ray CT

The conversion of cereal to vegetable represents a significant shift in land use in China, and it causes significant changes in soil properties. Most studies have only focused on chemical or biological properties; few have investigated soil structure. Soil structure, especially macropore space, is very important for plant growth because of its relation to important soil functions and processes, such as gas diffusion and water permeability. The objective of this study was to assess the effect of land use conversion from rice to vegetable on soil macropores (>50 μm) measured by computed tomography (CT) and to examine the relationships between CT-measured pore characteristics and soil chemical properties. By using space instead of time, we sampled three land uses – rice/wheat rotation (RWR), open-field vegetable (OFV) and plastic-greenhouse vegetable (PGV) – in a tilled and plow pan layer in a suburban area of Nanjing, China, and analyzed the basic physicochemical properties and CT-measured macropore characteristics. The results showed that the tilled layer soil had a significant response to the land use change. The macroporosity decreased from 11.5% under RWR to 8.0% under OFV and 5.8% under PGV, and the decreased portion consisted mainly of elongated large macropores (>1000 μm). In addition, the macropore morphology of vegetable fields also showed degradation, with a higher degree of anisotropy (DA) and lower fractal dimension (FD) and connectivity compared to those under RWR, but PGV experienced a higher degree of degradation than did OFV. This study also showed that soil structure degradation was significantly correlated with decreasing soil organic matter (SOM). Increasing the amount of organic fertilizer applied might improve the SOM content and therefore improve the soil structure. Based on the linear regression equation, adding 1 g of SOM per kilogram of soil can improve the macroporosity by 0.54 m3 m−3.

"Piler Dirt" Survey for the Sampling and Detection of Potato Cyst Nematodes.

Potato cyst nematodes are a significant threat to potato production worldwide and have important economic impacts due to yield losses but also because of the expenses associated with regulation procedures. In order to reduce the sampling labor, an alternative strategy named the "Piler Dirt" that collects the soil carried with potato tubers during their transfer to storage was proposed. The method showed a better sensitivity than the reference method to detect fields infested with G. rostochiensis. The quantification of the number of cysts per kilogram of soil was proportional between the two methods at low and moderate population densities (R2 = 0.885) but no correlations were found at high density. However, the quantity of soil generated by the method was exceedingly large to be treated by diagnostic labs. It was shown that subsampling six aliquots, each equivalent to 5,000 cm3/ha, from the total quantity of soil generated by the Piler Dirt method, resulted in a probability of 97% to detect infested fields, 95% of the time in our dataset. Overall, Piler Dirt appears as a good compromise to reduce labor time and cost without significantly affecting sensitivity. However, it will be challenging to implement because it needs to be done simultaneously with harvest and will require the participation of farmers during a busy period.

Environmental Risk and Toxicity Effect of Organophosphorus Insecticides on Male Red Earthworm (Eisenia foetida)

Organophosphate pesticides are widely used to eliminate pests in agriculture. In Arica- Chile, they were used to control and eliminate the plague of fruit fly (Ceratitis capitata). They act as acetylcholinesterase inhibitors and induce DNA damage. The aim of this study was to analyze the effects of malathion and methamidophos two organophosphate pesticides on male reproductive parameters of red earthworm Eisenia foetida. After determining the LD50 in mg per kilogram of soil (malathion= 880 mg/kg and methamidophos= 85.3 mg/kg), we proceeded to subdue Eisenia foetida at a dose of 1/10, 1/6, 1/3 and 2/3 of the LD50. The control groups were sprayed with water. All groups were analyzed at 1, 6, 15 and 30 days post treatment. The weight and external morphological changes was determined. Sperm count was held in camera Neubaur, DNA integrity was determined with Acridine orange test. The Ethics / Bioethics Committee at the University of Tarapaca, approved the research protocols. The results show that both organophosphate express a significant decrease in body weight in all animals treated with 100% of coiled tail. A significant rise in the number of sperm at 1, 6 and 15 days followed by a significant decrease from 15 to 30 days was observed. A significant increase of abnormal metachromatic sperm (red fluorescence) in all treated animals was observed. It is concluded that malathion and methamidophos, alter the external morphology, sperm count and quality of Eisenia foetida red earthworm. The use of these chemicals needs better handling and storage procedures to avoid altering human health and the environment.

Peranan Fungi Mikoriza Arbuskular (FMA) dan Serasah Daun Gamal (Gliricidia sepium L.) terhadap Pertumbuhan Bawang Merah (Allium cepa L.) pada Tanah Podzolik Merah Kuning

The aim of study was to know the effect of Arbuscular Mycorrhiza Fungi (AMF), Glomus mosseae on the growth of onion Allium cepa L. on red-yellow podzolic soils. Completely Randomized Design (CRD) factorial with 10 replicates was used in this experiment. The first factor was mycorrhizae, with two level: without inoculation as a control (M0); 10 gram inoculation = M1). The second factorwas leaf litter of gamal Gliricidia sepium L. species   wich were no litter as S0; 5 gram litter = S1; S2 was 10 gram of litter; and 20 grams of loitter in one kilogram of soil separately. Parameters used in this study were the growth of onion that has infected root in percent, and Relative Growth Rate (RGR). ANOVA was used to analyze the data, and followed with DMRT at 95% level test. The result showed that mycorrhizal inoculation increased root and shoot fresh weight, the dry weight of shoot; and the percentage of root infection on the onion. While the leaf litter of gamal increased only in leaf area. In contrast mycorrhizal inoculation and gamal leaf litter and their combination had no effect on other growth parameters. Key words: AMF, Glomus mosseae, Gliricidia sepium, Allium cepa.

Effect of Macrophomina phaseolina, organic manure and spent engine oil on Luffa aegyptica (Mill)

There is an increasing environmental concern over improper disposal of spent engine oil (SEO) from serviced engines. These concerns are the results of increasing pollution of the environment by SEO with its negative consequences on plants and other forms of life. The present study assessed the effect of Macrophomina phaseolina and nutritional amendment on Luffa aegyptiaca grown on spent engine oil polluted soil in a screen house. The effect of SEO and nutritional amendment on L. aegyptiaca was assessed on germination, plant height, leaf area, stem girt and number of leaves. Two concentrations of SEO (100 and 200ml) in four kilogram of soil were used in four replications each. Results show that SEO adversely affected the germination and growth of L aegyptiaca as delayed germination, reduction in heights, leaf area and number of leaves were observed in the crop planted in SEO polluted soil. Germination (emergence) of L. aegyptiaca seeds planted in SEO polluted soil began after four days compared to two days for plants in untreated soil. Germination efficiency for seeds planted in unpolluted soil was up to 100% but reduced to 20% when the soil was polluted with SEO. However, nutritional amendment and M. phaseolina increased seed germination in SEO polluted soil from 20% to 60%. Nutritional amendment and M. phaseolina were thus shown to enhance the germination and growth of L. aegyptiaca in SEO polluted soil.Keywords: Macrophomina phaseolina, Luffa aegyptiaca, Germination, Effect, Spent engine oil

Changes in microbial population during mycoremediation of diesel oil contaminated soil

The rates of bioremediation of diesel oil-contaminated soil were studied for a period of 12 weeks through changes in microbial population Two kilograms of soil moistened with 10% distilled water (w/v) was mixed thoroughly with diesel oil (5 and 10% concentrations respectively), and 3.6 × 10 6 ml spores of each fungal consortium were inoculated in the soil and exposed to natural conditions in the field for three months. Two controls without fungal inoculants were set up: C1OS (oil + soil-control 1), and C2OS (soil only-control 2). The results revealed that the populations of diesel oil utilizing microorganisms were higher at both 5 and 10% diesel oil pollution in the three soil amendments compared to the unamended control soil. The bacterial isolates were identified as species of Pseudomonas , Bacillus , Micrococcus , Staphylococcus and Escherichia , while the fungal isolates were identified as species of Aspergillus , Scopuloropsis , Cephalosporium , Penicilluim , Geotrichum , Mucor , Trichophyton and Microsporum . The pH (5.02 – 6.18) of the amended soil was lower compared to the unamended control soil (5.01 – 6.49) after 12 weeks. The moisture content of the amended soil (10.09 to 16.42%) was higher compared to the unamended control soil (8.14 to 11.39%) after 12 weeks. The results suggest that the isolates identified utilized the diesel oil as sources of carbon and nitrogen to proliferate. Keywords: Bioremediation, Consortium, Contaminated, Mycoremediation, Soil

Transformation-dissolution reactions partially explain adverse effects of metallic silver nanoparticles to soil nitrification in different soils.

Risk assessment of metallic nanoparticles (NPs) is critically affected by the concern that toxicity goes beyond that of the metallic ion. The present study addressed this concern for soils with silver nanoparticles (AgNPs) using the Ag-sensitive nitrification assay. Three agricultural soils (A, B, and C) were spiked with equivalent doses of either AgNP (diameter = 13 nm) or AgNO3 . Soil solution was isolated and monitored over 97 d with due attention to accurate Ag fractionation at low (∼10 μg L-1 ) Ag concentrations. Truly dissolved (<1 kDa) Ag in the AgNO3 -amended soils decreased with reaction half-lives of 4 to 22 d depending on the soil, denoting important Ag-aging reactions. In contrast, truly dissolved Ag in AgNP-amended soils first increased by dissolution and subsequently decreased by aging, the concentration never exceeding that in the AgNO3 -amended soils. The half-lives of AgNP transformation-dissolution were approximately 4 d (soils A and B) and 36 d (soil C). The Ag toxic thresholds (10% effect concentrations, milligrams of Ag per kilogram of soil) of nitrification, evaluated at 21 or 35 d after spiking, were similar between the 2 Ag forms (soils A and B) but were factors of 3 to 8 lower for AgNO3 than for AgNP (soil C), largely corroborating dissolution differences. This fate and bioassay showed that AgNPs are not more toxic than AgNO3 at equivalent total soil Ag concentrations and that differences in Ag dissolution at least partially explain toxicity differences between the forms and among soils. Environ Toxicol Chem 2018;37:2123-2131. © 2018 SETAC.