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INDIGENOUS BACTERIAL DIVERSITIES IN TWO AGRICULTURAL SOILS AS INFLUENCED BY CHEMICAL AND ORGANIC HERBICIDES
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Page will reload when a filter is selected or excluded.- Generalized Method of Moments 4 results 4
- Generating massive investment for growth and development has been one of the main policy goals of most economies around the globe. Countries, most especially developing ones, are highly susceptible to investment volatility owing largely to the fragile nature of their economies as well as weaknesses in terms of dysfunctional institutions. Therefore, sound economic management suggests the need to better understand possible sources for mitigating the adverse effects of investment volatility. Remittances have been identified as important capital flows which do a good job of dousing macroeconomic volatilities. It is on this basis that the study sought to uncover the causal relationship between remittances and investment volatility via the intermediating role of institutions. Using a panel of 70 countries and the system Generalized Method of Moments (GMM) estimator, three insightful outcomes come to the fore. First, remittances played countercyclical roles across the estimated regressions. Second, institutional quality had no significant role in mitigating investment volatility and lastly, the interactive terms of both remittances and institutions significantly mitigated the negative impacts of investment volatility with the exception of the political component of the institutional architecture. Policy suggestions are drawn based on our results. 4 results 4
- Remittance 4 results 4
- institutions 4 results 4
- investment volatility 4 results 4
- 16SrRNA 1 results 1
- Acrylic denture 1 results 1
- Agricultural soils as habitats for beneficial soil bacteria are usually invaded by weeds, an occurrence which has detrimental effects on crops. Chemical herbicides mostly employed for weed control adversely affect soil bacteria. Previous studies have reported chemical herbicides’ effects on soil bacterial diversity suppressing microbial growth, however, information on soil types, and organic herbicides that could be an alternative is limited. Therefore, this study was designed to investigate the effects of chemical and organic herbicides on bacterial diversity in Alfisol and Inceptisol. Soils (Alfisol and Inceptisol) were collected from research farms at University of Ibadan, Institute of Agricultural Research and Training, National Horticultural Research Institute, and International Institute of Tropical Agriculture. In a screen house experiment using a factorial arrangement in a completely randomised design, Atrazine and S-Metolachlor (AS-M), Isopropyl Amine (IA), and Acetic Acid (AA) herbicides were applied as pre-, post- and organic herbicides, respectively on the soils. In the field experiments, AS-M, IA and AA herbicides were also applied to the Alfisol and Inceptisol. All herbicide-treated soils were sampled at 4 and 8 weeks and bulked to determine physico-chemical parameters and herbicides persistency of the treated and untreated soils using standard methods. The effect on bacterial diversity in herbicide treated Alfisol and Inceptisol were determined by DNA extraction from the soil samples using 16S rRNA amplicons sequenced on illumina miseq. Data were analysed using descriptive statistics, QIIME 2, and ANOVA at α0.05. Untreated Alfisol pH (6.20±0.12), organic carbon (3.90±0.04g/kg) and clay content (112.20±0.55g/kg) were significantly higher than Inceptisol pH (5.50±0.15), organic carbon (1.90±0.01g/kg) and clay content (103.90±0.81g/kg). At week 4, pH and organic carbon were significantly higher in Alfisol (6.30±0.21: 0.40±0.06g/kg) than Inceptisol (5.40±0.21; 0.10±0.06g/kg). Herbicides’ persistency was higher in Alfisol than Inceptisol. Intermediate products (acetamide) in AA-treated soil (Alfisol: 30.2%; Inceptisol: 25.0%) < 2-amino-3-4- dihydro-4-4-dimethyl-6-pyrimidinone (Alfisol: 48.7%; Inceptisol: 35.3%) in IA < atrazine (Alfisol: 50.9%; Inceptisol: 37.1%) in AS-M at week 4, with a similar trend Alfisol: 22.1%, Inceptisol: 19.2%; Alfisol: 42.6%, Inceptisol: 33.2%; Alfisol: 43.9%, Inceptisol: 35.1% at week 8. Alfisol had significantly higher bacteria taxa of 79% than 21% in Inceptisol. Methylomicrobium, Saccharopolyspora, Domibacillus, Blatococcus, Fuctibacillus, Limnobacter, Sneathiella, Nocardiopsis, Aquisphaera, and Stenotrophomonas were found in Alfisol and Inceptisol. However, Limnobacter and Methylomicrobium; Sneathiella and Nocardiopsis; Aquisphaera and Saccharopolyspora; were the bacterial genera that survived in AS-M, IA and AAtreated-soils, respectively. Significant effect in relative abundance of bacterial genera Chthoniobacter (Alfisol: 0.5%, 0.4%, 0.3%, 0.6%: Inceptisol: 0.3%, 0.2%, 0.3%, 0.5%) and Pedosphaera (Alfisol: 0.6%, 0.6%, 0.5%, 0.9%, Inceptisol: 0.7%, 0.5%, 0.5%, 0.9%) were observed at week 4, Chthoniobacter (Alfisol: 0.5%, 0.4%, 0.4%, 0.6%: Inceptisol: 0.3%, 0.3%, 0.4%, 0.5%) and Pedosphaera (Alfisol: 0.6%, 0.8%, 0.5%, 0.9%, Inceptisol: 0.3%, 1.2%, 0.9%, 1.3%) at week 8 in untreated and soil treated with AS-M, IA and AA, respectively. Alpha and beta diversity indicated significant differences in the relative abundance of bacteria between Alfisol and Inceptisol. The relative abundance of bacteria diversity in Alfisol and Inceptisol were reduced by chemicals but increased by organic herbicides 1 results 1
- Alfisol and Inceptisol 1 results 1
- BCCA 1 results 1
- Calories 1 results 1
- Chemical and organic herbicides 1 results 1
- Creatine 1 results 1
- Domestic Resource Mobilization 1 results 1
- Earthquake 1 results 1
- Economic Growth 1 results 1
- Economic Growth (GDP) 1 results 1
- Economic globalization 1 results 1
- Ergogenic 1 results 1
- Financial Sector Development 1 results 1
- Focal depth 1 results 1
- Food crops 1 results 1
- Foreign Direct Investment 1 results 1
- Glycogen 1 results 1
- Gmelina arborea sawdust 1 results 1
- Gravity measurements were made along a roughly east-west profile across the lower Benue trough, with the main objectives of investigating the nature and configuration of the basement beneath the trough and determining the thickness of the sedimentary cover rocks. I87 gravity stations were established at 2-4km intervals and standard corrections were applied to the observed gravity values. A Bouguer gravity map of the whole Benue trough is compiled from the results of these measurements and data obtained from previous works. The map shows that the positive anomaly along the axis of the trough is a most prominent regional feature that extends over the whole length of the trough. The abrupt truncation of the positive anomalies along a NNE-SSE line may represent the Cretaceous continental margin. The axial positive is ascribed to the doming of the basement underlying relatively dense Albian Shales and their associated intermediate to basic intrusives along the trough axis as a result of tectonic processes. "Growth” of the positive anomaly towards the South is attributed to the basement being at a shallower depth in the lower Benue than in the upper Benue trough and to the probability that oceanic crust underlies the sediments at the southwestern end of the trough. The negative anomalies are due to thick sedimentary sequences which fill the flanks of the trough. The sediments are estimated to have a maximum thickness of 4.25km in the surveyed area of the lower Benue trough. 1 results 1
- Herbicide persistence 1 results 1
- Household welfare 1 results 1
- Hydraulic press 1 results 1
- In the first part of this thesis, a brief survey of the chemistry of veratramine viz. its occurrence, isolation and structural diagnosis is given. This part also includes a review of recent work on the stereochemistry and the synthetic work of other workers on the alkaloid. The main section describes three approaches to the synthesis of the C-Nor-D-homo ring system of the veratrum alkaloids. Howell and Taylor’s acetate diester 6(β-acetoxy-1 β:2αdi (methoxy carbonyl methyl)-9β-methyl-trans decalin prepared from 2:3:4:9:10:12- hexahydro-6-methoxy-12-methyl-2-oxophenanthrene was successfully cyclised to the potential intermediate 6(β -acetoxy-1 β:2α-( cyclopen- tan-3-one)-9-methyl-trans decalin. The pentanone was ring extended to give a solid substance which certainly contained the steroidal ring system of veratramine but which could not be obtained in the pure form. Attempts aimed at an easier preparation of the pentanone acetate by alkylating 1-oxo-6-ethoxy-8a-methyl-1,2,3,7,8, 8a hexahydro naphthalene with different alkylating agents were unsuccessful, the starting material being recovered in each case. In a second approach, 1-(2-cyanoethyl)-2-hydroxy naphthalene was converted to 2:3:4:9:10:12-hexahydro-6-methoxy-7-(3-bromo- propyl)-12-methyl-2-oxophenanthrene and 8-oxo-10a-methyl-1,2,3,4,5,6,8,9,10,10a-decahydro-1-oxa chrysene. The benzene nucleus of either intermediate was resistant to reduction and so they could not be used for further work. In the last attempt, 2-benzoyloxy-1,2,3,4,5,6,7,9,10,11,12,13 dodecahydro-12-methyl-7-oxophenanthrene was prepared starting with 2-naphthol and the tricyclic enone was successfully condensed with 2,2-ethylenedioxy-5-bromo pentan-2-one in the presence of potassium t-butoxide in t-butanol. The adduct was successively reduced, reacted with methyl magnesium bromide, deketalized y acetylated, ozonised and cyclised to give an oily substance which contained the veratramine steroidal nucleus as revealed by its U.V. spectrum. The oil did not crystallize. An oil which should probably crystallize more readily could be obtained if complete reduction of the original ansaturated adduct could be accomplished in the attempts some new compounds were prepared. These were mainly naphthalene, phenanthrene and hydrochrysene compounds. I.R U.V, or N.M.R. spectroscopic data were recorded for all the new compounds and for most of the known ones. Some structural formulae are repeated in the script, so as to aid the reader’s comprehension. 1 results 1
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