Studies on the biodiversity of soil microarthropod and their responses to precipitation regimes

In an attempt to determine the responses of soil microarthropods to precipitation regimes, samples were collected during dry season, simulated wet and rainy season periods. Also, biodiversity indices showed variation in soil microanthropod diversity and abundance in relation to cultivated, uncultivated and leaf litter sites. Generally, soil microanthropod abundance and species richness showed preference for the moisture rich sampling sites, with highest biodiversity indices recorded during the rainy periods.

Bacterial flora associated with some stages of Burukutu production

‘Burukutu’ which is an indigenous alcoholic drink has been shown to be rich in bacterial diversity, with a total of thirteen (11) bacterial species isolated from the three stages of production (namely: steeping, mashing and maturation) sampled from two different selling points in Ilorin, metropolis. The bacterial species isolated are Streptococcus sp; Lactobacillus sp; Bacillus sp; Pseudomonas sp; Klebsiella sp; Staphylococcus sp; Enterococcus sp; Escherichia coli; Proteus sp; Leuconostoc sp and Micrococcus sp.

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Acute toxicity of mesocarp of Azadirachta indica (L.) (Neem plant) on fingerlings of Heterobranchus bidorsalis

The piscicidal potential of water-extract mesocarp of Azardirachta indica was investigated in static biossay experiment with continuous aeration to determine its acute toxicity. The 96-hLC50 was 97.42mg/l while the threshold value was 31.12mg/l. The extract led to an initial increase in opercula ventilation rates which then decreased significantly. The computed regression equation (y) = 4.624 + 6.352 Logc. (r=0.72) and the fish exhibited respiratory distress, loss of balance and erratic swimming prior to mortality. The usefulness of A. indica as piscicidal plant is discussed.

Assessment of integrity of three dispersants and their toxicity to a Brackishwater Cichlid, Sarotherodon melanotheron (Cichlidae)

Key physical characteristics of three dispersants: Corexit 9527, NalcoD4106 and Goldcrew were studied to determine their integrity and toxicity to a brackishwater fish Sarotherodon melanotheron. The results showed that with regards to the physical properties, Corexit 9527 and to a large extent Goldcrew maintained their integrity while NalcoD4106 deteriorated. Observations of the 96h LC50 static bioassay showed that the toxicity of the dispersants to the fish in an increasing order is Corexit 9527 < Goldcrew < NalcoD4106.

Fungicidal effect of pawpaw (Carica papaya L.) leaf extracts on Fusarium verticilliodes

The in vitro effect of 10, 30 and 50% (w/v) concentrations of the aqueous and ethanolic extracts of pawpaw (Carica papaya L.) leaf on the radial growth of Fusarium verticilliodes was studied using the pour plate method. The diameters of radial growth of the mycelia of F. verticilliodes were measured at 24 hours intervals for five days. Both extracts retarded the radial growth of F. verticilliodes compared to that of the control, with the ethanolic extract having a greater fungistatic effect at the concentrations tested in this study.

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Salinity variations and distribution of Copepoda:Crustacea in the Lagos harbour system

: The copepoda (crustacea) of Lagos harbour system was studied from October 2002 to September 2003. Eighteen copepod species were identified, three of which are being recorded in Nigeria for the first time. Thesze are: Temora, Corycaeus and macrostella species. The copepods comprise of three assemblages, namely: the brackish/marine assemblage, the brackish assemblage and the brackish/freshwater assemblage. Salinity values varied from 33.40% at Lagos harbour to 0.40% at Badagry.

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First record of the Ectoparasite Salmincola species (Crustacea) from Nigeria water body

Plankton sampling and investigation of the Lagos harbour, some adjourning creeks and rivers was carried out using plankton, nets of 55µm and 100µm mesh sizes. Yewa river which is located between Lat. 6°25’ – 6°30’N and Long. 2°50’ – 2°55’E was one of the sampling, stations with salinity values ranging from 0.17 – 0.43% for the 8 months of sampling period, indicating a constant freshwater condition. In the course of analysis and identification of the copepoda, Salmincola species which is an ectoparasite of fish was found, and this is its first record from Nigeria water body

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Provenance and palaeoenvironment of the lower KerriKerri formation around Biri Fulani, North-Eastern Nigeria

The Kerri-Kerri formation Around Biri Fulani in North-eastern Nigeria is made up of reddish, modertaley well sorted, quartz arenites that are large scale cross-bedded. Field studies and laboratory analyses were conducted on these sediments to determine their depositional environments. Sieve analysis of sediments in the area of study showed that the sandstones within the Kerri-Kerri Formation are very leptokurtic and strongly fine-skewed. The sediments are texturally submature and mineralogically mature with angular to subrounded grains thus suggesting a moderate degree of reworking.

The Genetic Potential of the Nutritive Value of Beniseed (Sesamum indicum L.)

Seeds from 15 cultivars of beniseed grown in a southern guinea savanna agro-ecology were evaluated for their mineral composition as well as their physico-chemical characterization. Average percentage crude protein (15.40), crude fat (53.27), crude fibre (6.10), ash (2.33) and Nitrogen free extract (16.61) compare favourably with those of groundnut as a reference crop. However mineral composition are fairly similar in all the cultivars with calcium being the most abundant in two varieties (85-3-1 and T-4).

Integrity testing and toxicity of three dispersants to Chironomous transvaalensis Keiffer (Diptera:Chironomidae)

In-depth integrity testing of three dispersants: Corexit 9572, NalcoD4106 and Goldcrew was carried out to determine key physical characteristics of the dispersants and toxicity to the larvae of Chironomous transvaalensis Keiffer (Diptera:Chironomidae). The result revealed that Corexit 9527 and Goldcrew maintained their integrity while NalcoD4106 on the other hand deteriorated in storage. Static bioassay conducted to determine the 96hr LC50for the dispersants against the insect species showed that Corexit 9572 was the least toxic followed by Goldcrew and Nalco D4106.