Addition Of Chemical Fertilizers Research Articles

238 POSTER The selective proteasome inhibitor carfilzomib in combination with chemotherapeutic agents improves anti-tumor response in solid tumor xenograft models

The study investigated microbial population dynamics and petroleum hydrocarbon degradation during 56-day landfarming bioremediation of crude oil-polluted soil at a Community in Niger Delta Nigeria. Landfarming involved the addition of fresh top soil from unpolluted soil to the polluted soil followed by periodic ploughing. Active oleophilic bacteria identified by 16S rRNA sequencing were screened with 2,6-dichlorophenol indophenol (DCPIP) redox indicator for their degradation profile. Physicochemical parameters monitored during landfarming included the extractable Total Petroleum Hydrocarbons (TPH), Polycyclic Aromatic Hydrocarbons (PAHs), pH and heavy metals. TPH was more than 9000 mg/kg which exceeded the Department of Petroleum Resources’ (DPR's) intervention value of 5000 mg/kg. Total viable counts of culturable heterotrophic and hydrocarbon utilizing bacteria in the polluted soil pre-landfarming were between 0.2 and 0.5 × 103 cfu/g. Monitoring of microbial population dynamics on days 0, 9, 18, 36 and 56 revealed an increase in hydrocarbon utilizing bacterial population from 104 up to 107 cfu/g which correlated significantly (R = 0.88; p = 0.05) with TPH reduction to below 700 mg/kg by day 56 when bioremediation experiment ended. Pseudomonas aeruginosa was the most efficient diesel degrader which showed 100% DCPIP decolourization. Acinetobacter, Myroides, Pseudomonas and Bacillus were central in the degradation of the long chain hydrocarbon fraction in the spill site. The fungal classes recovered included Eurotiomycetes, Saccharomycetes and Sordariomycetes. The findings from this study showed that the addition of virgin top soil to a compromised and chemically stressed soil is a green and eco-friendly strategy for enriching microbial degradative activities without addition of chemical fertilizers.

Influence of Manure and Fertilizer on Baccharis trimera (Less.) D.C. Growth and Essential Oil Yield

ABSTRACT Baccharis trimera plants, grown in soil containing 0, 5, 10, 20, or 30 percent (w/w) manure in greenhouse experiments, had improved plant color and growth (increased height, branching, and number of nodes) at the higher nutrient levels as compared with the control without the addition of manure. Generally, the addition of chemical fertilizer to the manure-containing media further increased yields as compared with yields having only manure. The addition of chemical fertilizers to manure-containing pots, however, did not increase the concentration of essential oil in plant tissue. Oil yields were the highest, however, in plants having both manure and chemical fertilizer due to the increased biomass production. No differences in the essential oil constituents were observed between plants grown with or without fertilizer.

Artificial Inoculation—Perspectives in Tailings Phytostabilization

ABSTRACT Intensive mining and processing activities worldwide resulted in the generation of huge amounts of waste (tailings), generally characterized as toxic, radioactive, and/or hazardous. The exposure potential and, hence, the risk posed by such wastes is enhanced by a general lack of vegetation. Phytostabilization has proven to be efficient in reducing this risk. However, establishing vegetation on tailing dumps may be expensive due to the intensive use of amendments and chemical fertilizers. In this article, investigations on artificial inoculation of mine tailings with bacterial strains as a means to improve the development of vegetative covers and reduce application cost by eliminating chemical fertilization are presented and discussed. The development of plants and microbial communities from tailings, as well as the impact of inoculation on metal uptake in plants, were studied. Experiments were carried out in greenhouse using two types of mine tailings (phosphogypsum and sulphidic tailings) from the Romanian Black Sea coast. Indigenous herbaceous plants were cultivated on tailings with the addition of chemical fertilizers versus bacterial inoculation. After a 6-month experimental period, excellent plant growth, which is associated with a rich microbial community, was observed in all inoculated treatments, in contrast with poor plant growth and microbiota from the chemical fertilization treatments alone. Additionally, artificial inoculation improved plant resistance to heavy metals by reducing the uptake of some toxic metals. Once a rich microbial community is established, inoculation may be discontinued. Based on these results, efficient and cost-effective phytostabilization schemes can be proposed.

Contents of minerals in green leafy vegetables cultivated in soil fortified with different chemical fertilizers.

Content of selected minerals in spinach (Spinacea oleracea) and ambat chuka (Rumex vesicarius) cultivated in soil fortified with different chemical fertilizers was determined in a pot experiment. Addition of NPK (Nitrogen, Phosphorus and Potassium) fertilizer along with micronutrients, iron and zinc, enhanced the concentration of zinc, iron and magnesium in selected green leafy vegetables markedly (p < 0.05), while the concentration of copper was not altered significantly (p > 0.05). Potassium content in the green leafy vegetables was not affected (p > 0.05) by the addition of chemical fertilizers to soil. Spinach and ambat chuka differed remarkably in their mineral contents. Contents of potassium, zinc and copper were significantly high in spinach, while the contents of magnesium and iron were markedly high in ambat chuka (p < 0.05).

Recovery assessment of lumber mill wastes: composting product field test

Lumber mill waste with more than monthly generation of 5000 tons is one of the main solid waste sources in the local I-Lan area. The lumber sawdust together with seafood processing residue and distiller byproducts, is evaluated within a composting machine as a disposal alternative to the conventional landfill and incineration methods. The addition of seabird manure provides adequate P source for the eventual composting product to be used as an alternative organic fertilizer to conventional chemical fertilizer. Thermophilic bacteria were added to facilitate composting reaction at 70°C. The composting product was further evaluated for effectiveness as organic fertilizer in greenhouse and field studies. The tested plants include Zinnia elegans, Celosia cristata and Asplenium nidus L. The control experiments include soil alone as well as soil with the addition of chemical fertilizer or compost product. The experimental results demonstrate that flower growth of the C. cristata is enhanced in the presence of composting product. The cost analysis indicates that it is economically feasible to yield a useful composting product.

NATURAL RECYCLING OF NUTRIENTS vs. CHEMICAL FERTILIZERS ON SHADED COCOA PLANTATIONS

Eight-year-old cocoa trees growing under shade of different tree species were treated during three years with foliar and soil fertilizers and compared to non fertilized trees. We hypothesize that non fertilized trees under shade condition recycle their own nutrients by using fallen foliage from the shade trees and, in a fertile soil, they do not need addition of chemical fertilizers. Eight treatments, selected from growers' technology were evaluated under a randomized complete block design with 4 replications and 12 trees per experimental unit. Fertilized treatments did not differ from the non fertilized treatment in dry bean production and tree growth. This indicates that shaded cocoa plantations established in good fertile soils sustain their own nutrient requirements. The results also showed that foliar urea (1%) reduced cherelle wilt (yellowing and subsequent shriveling of young fruits).

Long fallow periods: The key to sustenance of soil fertility?

Changes in N, P, K, Ca and Mg in soil and rice plants were investigated during a cropping season following a long fallow period in a system of traditional cultivation practised for several centuries, under a village tank irrigation system. Soil, N, P, K, Ca and Mg were not found to be deficient for rice production throughout the season. Flooding did not produce toxic levels of Fe and Na and soil pH remained at 6.4 during the season. The average grain yield (3.5 t/ha) without any addition of chemical fertilizer was almost the same as that from fields under major irrigation systems where fertilizer application (less than the recommended level) was common. The sustainability of soil fertility under the traditional system of rice cultivation appears to be dependent upon long fallow periods. The natural build-up of soil fertility during a three-year fallow was evidently adequate to support a good growth of the crop which produced a yield comparable to that obtained in chemically fertilized, more intensively cropped rice fields under major irrigation systems.

Studies on soil-borne cereal mosaics

Barley yellow mosaic is spread throughout Japan except Hokkaido, but there has been no published information on the occurrence of the disease in foreign countries. Barley yellow-mosaic virus (BYMV) is transmitted only to susceptible varieties of barley through the soil in the winter and produces mottling which resembles that in wheat caused by wheat yellow-mosaic virus (Marmor tritici var. fulvum McK.). BYMV does not attack wheat and rye. Intracellular inclusions (X-bodies) are present in the cells of the diseased plants.The writer has carried out experiments in order to learn about the mode of the disease and properties of BYMV. The experimental results are summarized as follows:(1) BYMV is transmitted, with difficulty, to healthy barley plants by the rubbing method of incoulation with pressed sap of diseased plants. The virus is not transmitted by insects and is not seed-borne.(2) Regarding the effect of the environmental conditions upon expression of symptoms, it is observed that the symptoms of plants were rendered less striking by rising temperature and by the addition of chemical fertilizer.(3) Fifteen cm. below the seeds was the greatest distance at which BYMV-infested soil caused the disease. Thermal inactivation point of the virus in soil was 50-60°C for 10 minutes.(4) When pregerminated seeds, which had already developed 2 or 3 roots, were planted in virus-infested soil in glass-house, the infection rate was 2-3 times higher than in the cases of planting seeds, which were presoaked but not yet developed roots.(5) Only a small number of plants were in fected when grown in soil composed of 10-50μ particle fraction or of nearly 50μ fraction separated from BYMV-infested soil.

II.—A Fish Cultivation Experiment in an Arm of a Sea-loch. II. Observations on some Hydrographic Factors in Kyle Scotnish

Summary1. The site (Kyle Scotnish) of an experiment to test the effect of the addition of chemical fertilizers (N and P) to an arm of a sea-loch is described.2. Certain physical conditions of the loch are recorded, including the tides, which were of a peculiar form.3. Methods used in the measurement of water movements are described, and the results used to calculate the rate of exchange of Kyle Scotnish water with the water outside the loch. At spring tides this exchange was estimated at less than 8 per cent, of the volume of Kyle Scotnish.4. The additional corroborative evidence obtained by tracking marked water masses within the loch is presented.5. The quantities of fertilizer used are tabulated, and results given which demonstrate its rapid removal from the water.6. The significance of the low rate of water exchange is discussed. This low rate of exchange makes possible the increase in productivity of Kyle Scotnish, brought about by the addition of chemical fertilizers.

FUNGI ISOLATED FROM MANITOBA SOIL BY THE PLATE METHOD

The fungus-flora of 75 samples of surface soils from various parts of Manitoba has been analyzed. The population of fungi in these soils is abundant and varied despite climatic conditions which might appear unfavorable. Forty-four genera and 100 species of fungi have been identified, and the relative frequency of each determined. It has been found that the methods of soil microbiology give data regarding the parasitic as well as the saprophytic fungi in soils; that Trichoderma lignorum parasitizes certain other fungi, and thus may play a part in keeping in check the pathogenic fungi within a soil; and that the addition of chemical fertilizer to a soil results in a prompt and consistent increase in the fungus-flora.