African Journal of Soil Science

African Journal of Soil Science ISSN 2375-088X Vol. 7 (7), pp. 001-005, July, 2019. © International Scholars Journals

Full Length Research Paper

Amendment of crude oil contaminated soil with sawdust and chromoleana leaves for optimum plant protection

Offor, U.S. and Akonye, L.A.

Department of Plant Science and Biotechnology, Faculty of Science, University of Port Harcourt, Port Harcourt, Nigeria.

Accepted 16 March, 2019

Abstract

A study on the effectiveness of sawdust and chromoleana leaves as soil restorative measures to optimize plant growth at two intensities of crude oil contamination showed that both restore parity on the growth parameters (leaf area, leaf ratio, relative leaf growth rate, relative growth rate, and net assimilation rate) of crops tested compared to control. However, chromoleana leaves was found to be more effective than sawdust. The test crops Zea mays and Vigna unguiculata differed with respect to their response to amendments applied. V. unguiculata showed better response than Z. mays in most of the parameters tested.

Key word: oil contamination, soil amendments, Bioremediation and plants growth.

African Journal of Soil Science ISSN 2375-088X Vol. 7 (6), pp. 001-006, June, 2019. © International Scholars Journals

Full Length Research Paper

Growth study on chrysene degraders isolated from polycyclic aromatic hydrocarbon polluted soils in Nigeria

Igwo-Ezikpe Miriam Nwanna¹*, Gbenle Olabode George¹ and Ilori Matthew Olusoji²

¹Department of Biochemistry, College of Medicine, Idi-araba, University of Lagos, P.M.B. 12003, Lagos, Nigeria.

²Department of Botany and Microbiology, Akoka, University of Lagos, P.M.B. 12003, Lagos, Nigeria.

Accepted 13 April, 2019

Abstract

Acinetobacter anitratus, Alcaligenes faecalis, Acinetobacter mallei and Micrococcus varians were isolated from polycyclic aromatic hydrocarbon polluted soils by enrichment culture using chrysene as sole carbon and energy source. Physiochemical evaluation revealed that these isolates grew well at a temperature range of 20 - 40°C, pH 6.0-8.0 but less tolerable to various salt concentrations except Micrococcus varians which grew at 1.0 to 7.5% NaCl. These organisms utilized chrysene, anthracene, naphthalene, crude oil, kerosene, diesel and engine oil as sole carbon source. None could utilize benzene, hexane, xylene, phenol and toluene as carbon sources. Growth study of the isolates on 0.1% (w/v) chrysene resulted in highest cell density of 8.8x10⁷, 7.9x10⁷, 6.3x10⁶, 6.3x10⁶ cfu/ml for A. anitratus, Alc. faecalis, A. mallei and M. varians, respectively. There was statistical significant difference (P< 0.05) in the growth of these organisms on chrysene as sole carbon and energy source when compared with non-chrysene control. This study indicates the potential of these hitherto unreported tropical bacterial strains as chrysene degraders and their use in biodegradation processes involving petrochemical products.

Key words: High molecular weight, polycyclic aromatic hydrocarbons, crude oil, tropical bacteria, chrysene, biodegradation.

African Journal of Soil Science ISSN 2375-088X Vol. 7 (5), pp. 001-004, May, 2019. © International Scholars Journals

Full Length Research Paper

Symbiotic effectiveness of acid-tolerant Bradyrhizobium strains with soybean in low pH soil

C. Appunu* and B. Dhar

Microbial Genetics Laboratory, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi-221005, INDIA

Accepted 23 March, 2019

Abstract

Eight acid tolerant strains of Bradyrhizobium isolated from soybean plants grown on acid soils in Madhya Pradesh, India, were examined for their ability to survive in soil and YEMB at low pH levels. All the tested isolates survived in acidic (pH 4 -6) conditions and their survival capacity was higher in soil than in nutrient medium at same levels of low pH. Variation among different strains showed that there is potential to improve strain performance under stress conditions. Further, symbiotic effectiveness of these strains was determined under the polyhouse conditions in sterilized soil (pH 4.5). Highest and lowest symbiotic characters, dry matter production and nitrogen improvement per plant were observed in PSR001 and NSR008 inoculated plants, respectively. All the examined isolates showed considerable variability in their symbiotic performance. The strain found to be more tolerant to stress were more effective N₂ fixers in symbiosis with soybean in acid-soil conditions.

Key words: Symbiotic effectiveness, Bradyrhizobium strains, pH, soybean.

African Journal of Soil Science ISSN 2375-088X Vol. 7 (5), pp. 001-004, May, 2019. © International Scholars Journals

Full Length Research Paper

-Amylase production by Penicillium fellutanum isolated from mangrove rhizosphere soil

K. Kathiresan* and S. Manivannan

Centre of advanced study in Marine Biology, Annamalai University, Parangipettai, 608502, Tamilnadu, India.

Accepted 04 March, 2019

Abstract

The effects of pH, temperature, incubation time, salinity, sources of carbon and nitrogen were tested in submerged fermentation process in production of -amylase by Penicillium fellutanum isolated from coastal mangrove soil. The production medium without addition of seawater and with provision of maltose as carbon source, peptone as nitrogen source, incubated for 96 h, maintained with pH of 6.5 at 30^oC, was found optimal for production of -amylase by P. fellutanum.

Key words: -amylase, Penicillium fellutanum, mangroves, rhizosphere soil, Rhizophora.

Key words: Sorption, calcareous soils, cellulase.

African Journal of Soil Science ISSN 2375-088X Vol. 7 (5), pp. 001-007, May, 2019. © International Scholars Journals

Full Length Research Paper

Biodegradation and dissipation of ¹⁴C-carbofuran in clay soil from Loukkos perimeter, Northwestern Morocco

BENICHA Mohamed¹*, MRABET Rachid² and AZMANI Amina³

¹Laboratory of Pesticides residues, UR research on nuclear techniques, environment and quality, Regional Center of Agronomic research, 78, Bd Mohamed Ben Abdellah, 90010 Tangier, Morocco.

²Regional Center of Agronomic research, 78, Bd Mohamed Ben Abdellah, 90010 Tangier, Morocco.

³University Abdel Malik Essaadi, Faculty of Science and Technology, Ancienne Route de l'Aéroport, Km 10, Ziaten. BP: 416. Tanger – Maroc.

Accepted 21 March, 2019

Abstract

Mineralization and dissipation of ¹⁴C-ring labeled carbofuran (2, 3-dihydro-2, 2-dimethylbenzofuran-7-yl-methylcarbamate), one of the highly toxic N-methyl carbamate pesticides, in an untreated Vertisol Moroccan soil used for sugar beet cultivation was studied under laboratory conditions over a period of 63 days. The experiment was conducted in flooded and non-flooded conditions. Carbofuran mineralization was determined by monitoring the ¹⁴CO₂ production from soil amended with U-ring¹⁴C-carbofuran. Under both conditions, higher mineralization rates of ¹⁴C-carbofuran were observed. The extent of mineralization being more in moist (19.2%) than in flooded conditions (12.4%). In both conditions, the soil extractable pesticide residues decreased with time, while the bound residues gradually increased. The extractable ¹⁴C-activity disappearance rate was much higher in flooded than in non-flooded conditions. At the end of the experiment, 15.8% and 31% of applied dose were recovered as extractable residues under flooded and moist conditions respectively. Soil bound residues were formed to the extent of 33.3% of the applied dose in flooded soil, while 29.1% was formed in non-flooded soil. The amount of the organic volatiles was much higher in flooded condition (18.2%), as compared to 5.6% in non-flooded soil. The main degradation product formed was carbofuran phenol.

Key words: Carbofuran, mineralization, degradation, volatilization, ¹⁴C, biodegradation.