Recent Advances in Biological Research Vol. 6

The major objectives of this study were to identify spectral characteristics associated with rice yield and to establish their quantitative relationships. Field experiments were conducted at Shi-Ko experimental farm of TARI’s Chiayi Station, during 2001 to 2005. Rice cultivar Tainung 67 (Oryza sativa L.), the major cultivar grown in Taiwan, was used in the study. Various levels of rice yield were obtained via nitrogen application treatments. Canopy reflectance spectra were measured during entire growth period and dynamic changes of characteristic spectrum were analyzed. Relationships among rice yields and characteristic spectrum were studied to establish yield estimation models suitable for remote sensing purposes. Spectrum analysis indicated that the changes of canopy reflectance spectrum were least during booting stages. Therefore, the canopy reflectance spectra during this period were selected for model development. Two multiple regression models, constituting of band ratios (NIR/RED and NIR/GRN) were then constructed to estimate rice yields for first and second crops separately. Results of the validation experiments indicated that the derived regression equations successfully predicted rice yield using canopy reflectance measured at booting stage unless other severe stresses occurred afterward.

We also integrated multiple regression models, derived from reflectance spectrum measurements and using band ratios (NIR/RED and NIR/GRN) as independent variables, with SPOT 5 multispectral images taken at booting stage to predict rice yield before harvest. A 4.8-ha paddy rice field was used as testing ground for the accuracy of prediction with the rice yield prediction model. Within the site, different rice yield scenarios were produced by using combinations of rice varieties, Japonica and Indica type, nitrogen rate and drought treatments. Rice yields harvested in 10m X 10m mesh were used as ground truth data for comparison. The regional rice yield map is produced with the rice yield prediction model using SPOT 5 images taken at booting stage in this study. The results from the regional rice yield map shows that the relative errors between actual yield and predicted yield in the first season and second season in 2014 are lower than 5%. Those have demonstrated its potential for using SPOT 5 images to estimate the regional rice yield with the rice yield prediction model derived from reflectance spectrum measurements and using band ratios (NIR/RED and NIR/GRN) as independent variables.

Lake Victoria region has the highest HIV prevalence in East Africa due to concentration of commercial farms, fishing and mining that escalate social dynamic interactions. High rates of HIV transmission and poor working conditions further amplify the risk of TB in the region. Local populations in the area have opted different alternatives among which medicinal plants are popular for managing health conditions related to the respiratory diseases. Consequently, selective consumerism of plants for managing respiratory diseases profoundly affects diversity of priority medicinal plants. Detection of the effect of selective consumerism to the preferred plants in-situ is not instantaneous unless much focused approach is employed. In this study, an ethnobotanical assessment criterion was used to assess and identify conservation status for most useful plants. To achieve this, open ended questionnaires and focus group discussions were used for collecting ethnobotanical information from 37 traditional health practitioners on the use of herbal remedies against various respiratory diseases. Guideline by the international union for conservation of nature (IUCN) medicinal plant specialist group was used to assess qualitative distribution of indicator species through ethnographic methods. A protocol for conservation assessment management plan was used to prioritize limited number of species for ex-situ conservation. Ethnobotanical parameters, value–index and legislation-index were used for scoring in two-dimensional manner. Scoring analysis highly prioritized non-timber plants including Rubia cordifolia, Crassocephalum manii and Pavetta crassipes for conservation over timber species. From the findings, an ethnobotanical assessment criterion is recommended for total conservation of all plant categories in the wild including the often neglected non timber plant species.

Okra (Abelmoschus esculentus (L.) Moench) is a vegetable crop belonging to the family of Malvaceae. It is extensively grown in the tropic and sub- tropics but had its origin in Central Africa. One of the cultural practices that farmers used in controlling weeds in okra farm is spacing. It is a distance between one cultivated crop and another. The spacing between rows and along rows varies one type of crop to another. Field experiment was carried out in late 2015 and repeated in early 2016 cropping season at the Teaching and Research Farm of the University of Port Harcourt, Choba, Rivers State, Nigeria to determine the appropriate spacing and weeding regimes for okra production. Three spacing (60 cm x 15 cm, 60 cm x 20 cm and 60 cm x 30 cm) and three weeding regimes [no weeding, weekly weeding, and twice at 3 and 7 weeks after planting (WAP)] were used. The experimental design was a 3 x 3 factorial scheme laid out in a Randomised Complete Block Design (RCBD) with three replications. The results showed that plant spaced at a closer spacing of 60 cm x 15 cm suppressed weeds better than other spacing in both years of study. Okra performance was better at closer spacing of 60 cm x 15 cm than in other spacing regimes. Similarly, weedy check had higher weed growth and least performance than other weeding regimes. There was significant interaction between spacing and weeding regimes. Plant spaced at closer spacing of 60 cm x 15 cm combined with weekly weeding plots had the lowest weed density and dry weight of 0.00 plants /m² and 0.00 g/m² in both years of study. While 60 cm x 30 cm combined with no weeding gave the highest weed density and dry weight (395.00 plants/m² and 306.33 plants/m²) and (88.33 plants/m² and 95.33 g/m²) in the late and early 2015 and 2016 cropping seasons respectively. The interaction effect further showed  that the highest fresh pod yield  was obtained from  plant  spaced at 60 cm x 15cm with weekly weeding (3.02 t/ha and 2.26 t/ha)  followed by  60 cm x 15 cm  with twice weeding  at 3 and 7 WAP (2.96 and 2.22 t/ha). While, plant spaced at 60 cm x 30 cm with no weeding had the lowest fresh pod yield (0.08 t/ha and 0.03 t/ha). Since, the yield obtained from 60 cm x 15 cm with twice weeding (3 and 7 WAP) was not statistically different from 60 cm x 15 cm weekly weeding, for economic considering the former could be recommended.

Aim: To determine if there was any association between urogenital schistosomiasis and HIV infection among children in Ore Community, Southwestern Nigeria.

Methodology: Urine samples were collected from 438 children and examined microscopically for ova of Schistosoma haematobium. A sample of 3 ml of blood was drawn from each participant for HIV test. Antibodies to HIV were determined using Determine HIV1/2 kit, Unigold kit and enzyme linked immunosorbent assay (ELISA).

Results: The overall prevalence of S. haematobium infection was 30.1% while that of HIV infection was 0.9%. None of the 132 S. haematobium infected children had HIV infection while 1.3% of the 306 children negative for S. haematobium were positive for HIV test.

Conclusion: This study did not show any evidence of association between urogenital schistosomiasis and HIV infection among children in Ore, Southwestern Nigeria. Therefore, urogenital schistosomiasis may not play a significant role in the spread of HIV infection in a locality where HIV prevalence is low.

Aim: Physicochemical assessment of the surface water sourced from River Ebenyi and its tributaries in Eha-Amufu and environs, Isu-Uzo Local Government Area of Enugu State of Nigeria.

Place and Duration: Eha-Amufu and environs, Isu-Uzo Local Government Area of Enugu State of Nigeria May to July, 2017.

Study Design: Experimental design.

Methodology: Water samples were spatially collected along the river and stream channels in Eha-Amufu and the adjoining Ihenyi, Amaede, Mgbuji, Umuhu, Agamede and Odobudo villages. Parameters analysed include pH, dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), Total hardness (TH), Lead (Pb), Copper (Cu), Cadmium (Cd), Chromium (Cr), Zinc (Zn), Nitrate, Phosphate, Chloride and Sulphate.

Results: The concentrations of Cd (0.02-0.05 mg/l) and Pb (0.37-0.77 mg/l) exceeded the maximum limit of the range of values considered as safe by the World Health Organisation (WHO). Conductivity (37.14 – 63.30 µs/cm), Total dissolved solids (TDS) (10.80 – 30.80 mg/l), Total suspended solids (TSS) (10.60 – 21.20 mg/l) and Total solid (TS) (20.60-41.00 mg/l) were within the lower limit of the permissible range of values. Chromium (0.26 ± 0.00 mg/l) exceeded the maximum permissible limit at Agamede village. Sulphate was statistical significantly higher (χ² = 25.697, p < 0.001) relative to the spatial concentrations of nitrate (4.28 – 11.18 mg/l), sulphate (13.68 – 25.23 mg/l), phosphate (0.00 – 0.28 mg/l) and chloride (9.11 – 15.50 mg/l) in the area.

Conclusions: The baseline results obtained from this study with regards to Cd, Cr and Pb demands that effective health education programme should be organised to emphasize on the effect of anthropogenic activities that releases pollutants. However, long term sampling covering all the months of the year is needed in order to confirm the reproducibility of our results. Variations in the physicochemical parameters of the surface water sourced from River Ebenyi and its tributaries in Eha-Amufu and environs are indicative of the influence of the anthropogenic activities. The baseline results obtained from this study with regards to Cd, Cr and Pb demands that effective health education programme should be organised to emphasize on the effect of anthropogenic activities that releases pollutants. However, long term sampling covering all the months of the year is needed in order to confirm the reproducibility of our results.

During studies on tabanid fauna on Marambaia Island, Mangaratiba, Brazil, the authors captured 71specimens of two species of solitaire sand wasps hunting horseflies, Stictia punctata (Fabricius, 1775) and Stictia signata signata (Linnaeus, 1758). Wasps interact with horseflies demonstrating outstanding behavior, interrupting the hematophagism, which enhances tabanids ability to transmit pathogenic agents to natural hosts.

Environmental contaminants are having a major impact on receiving ecosystems including air, soil and surface water. Wastes resulting from human activities mostly end up in surface water through deposition and indirectly through runoff. Indiscriminate application of pesticides and the remains of empty cans are often improperly discharged. This possess a threat to the aquatic system especially amongst communities close to surface water resources. In Nigeria, the use of 2, 2- dichlorovinyl dimethyl phosphate (an organophosphate insecticide) for the control of insects in household settings, agricultural field practice and in storage facilities abounds. 2, 2- dichlorovinyl dimethyl phosphate has different trade names depending on the region. This study reviewed the toxicity associated with 2, 2- dichlorovinyl dimethyl phosphate. The study found that the toxicants induces behavioural and morphological alteration, histopathological, haematological, biochemical, enzymatic, electrolytes and developmental defects and death depending on the concentration and exposure duration. The study also found that insecticides containing 2, 2- dichlorovinyl dimethyl phosphate is toxic to fish even at low concentrations (0.2 – 2 ppm). Hence, there is the need to exercise caution in the use and disposal of empty cans of 2, 2- dichlorovinyl dimethyl phosphate close to surface water.

Non-biting surveys in urban, rural and forested areas of Akwa Ibom State, Nigera, using rotten meat, fish, fruits and human faeces, for collection yielded 4290 and 2474 flies from 9 families in the wet and dry seasons, respectively. Synanthropic Indices (SI) of 15 species were calculated for the wet season, of which 10 species were positively synanthropic and five negatively synanthropoc to human settlements. In the dry season, the SI of all the 9 species computed were positive for human settlements. Significant bait preferences were shown only in the wet season by Chrysomya albiceps (F=10.2⁺⁺⁺; P<0.05) for rotten meat and Poecilosomella angulata (F+9.6+++; P<0.05) for human faeces.

Phosphorus (P) is the second important macronutrient after nitrogen and important at all growth stages of plants including rice. It is an important constituent of macromolecules like DNA, RNA, ATP, phospholipids etc. and a major repository of chemical energy. P availability is optimum at neutral pH. Phosphate solubilizing microbes (PSM) viz. Bacillus, Azotobacter, Pseudomonas, Aspergillus spp.  recycle  the  nutrients  like  N,  P,  C,  K,  S,  Fe  etc. and promote growth of plants. The endophytes like Rhizobium, Azospirillum, Pseudomonas spp., epiphytes like Rhizobium, Pantoea spp., rhizospheric organisms like Bacillus, Pseudomonas, Erwinia spp. and entomopathogens viz. Beauveria, Metarhizium,   Nomuraea spp. mineralize insoluble P to make accessibility to plants. Soil enzymes also solubilize organic phosphates (OP) to available forms. Oxidation of glucose to gluconic acid, production of organic and inorganic acids, ammonia, H₂S etc. are major mechanisms for P mineralization by microbes. So, phosphate solubilizing microbes would be efficient biofertilizers as they promote plant growth, improve soil properties and prevent plant pathogens without any harsh effect on the environment.

Herbal Medicines (HM) are being used in our country for a long time but the  type and load of the microbial agents has not been isolated in locally produced finished products of HM. The present study was designed to assess the microbial load, genus & species of the microbes contaminating with HM. Seven different Antidiabetic Herbal Preparations (ADHPs) were purchased randomly and analyzed for microbial contaminants. Blood agar, Mac Conkey agar, Chocolate agar and Saboraud’s dextrose agar were used (Oxoid) for culturing and isolation of bacteria and fungus. Identification of organisms were done as standard ways. Total aerobic bacterial plate count was done as per the method of Brown, Poxton and Wilkinson. Out of 07 anti diabetic solid and liquid samples, except ADHP-3, Bacillus subtilis (3.5 – 4.0 x 104 cfu/g) was isolated from solid ADHPs and Enterococcus spp. (1.0x104 cfu/ml) was isolated from liquid ADHP, but all samples were free from fungi (yeasts and moulds). However presence of bacteria in these samples indicates the possibility of increased number of bacteria. So, the sample should be handled in any step maintaining standard sterility of the environment, instrument and involved personnel. The result of present study showed the contamination rate within tolerable level but the presence of bacteria in these samples was not desirable.  

Soil Transmitted Helminths (STHs) are of great Public Health importance. The present study was designed to evaluate the prevalence and pattern of STHs among Primary School Children at Nnewi, Nnewi North Local Government Area of Anambra State, Nigeria. 250 school children aged 1-12 years were randomly recruited from 5 major primary schools at Nnewi between January and June 2017. 95 (38%) were males while 155 (62%) were females. Stool samples were collected using universal sterile containers and examined microscopically using saline floatation method. Out of the 250 pupils examined, 105 (42%) were positive for at least one STH. 40 (42.1%) of the males examined were positive while 65 (41.9%) of the females were positive. There was no significant difference between sexes (P > 0.05). Children aged 1-5 years had the highest prevalence (62.2%), followed by those aged 6-8 years (33.3). Children aged 9-12 years had the least prevalence. Prevalence was significantly different between the different age groups (P < 0.05). Among the STHs isolated, Ascaris lumbricoides was the most prevalent (22%), followed by Hookworm (14%). The least prevalent was Trichuris trichiura (6%). No case of mixed infection was detected. The study concludes that STHs are of immense public Health importance in primary School children at Nnewi and efforts should be intensified to promote health education, personal hygiene and sanitation and regular deworming of school children. In conclusion, STHs have remained endemic in the study area in particular and Nigeria in general and is a major source of public health concern. Strict environmental sanitation, provision of adequate water supply, good housing, coupled with health education will go a long way towards its eradication. This should be the target of all governments in Nigeria.

The herbicide dichlobenil is widely used to control unwanted weeds in non-agricultural areas and aquatic environment. When released into environment, it may harm the growth of algae, which in turn might disturb the balance of aquatic ecosystem. Herein, the physiological as well as the biochemical responses of two fresh water algae, namely Ankistrodesmus acicularis (Chlorophyta) and Anabaena flos-aquae (Cyanobacteria), to different concentrations of dichlobenil were assessed. Parameters, including chlorophyll (a) Content, EC₅₀ values, carbohydrate and adenosine triphosphate (ATP) contents as well as the uptake by both algal species were evaluated. We found a significant decrease in chlorophyll (a) content of both algal species to intermediate and high concentration of dichlobenil, whereas stimulative effect was observed for low concentration of dichlobenil on Chl (a) content. Attainable results derived by probit analysis revealed that the EC₅₀ values at 5^th and 7^th days were approximate to each other for both algal species. Furthermore, a drastic decrease (98%) in ATP content was noticed at 8.0 mg/L dichlobenil treatment in case of Ankistrodesmus acicularis. On the other hand, the activity of Anabaena flos-aquae cells was enhanced by the application of low and intermediate concentrations of dichlobenil (0.25-4.0 mg/L). Notably, higher concentration level (16.0 mg/L) causes substantial decreases in ATP content. Ankistrodesmus acicularis was found to be more sensitive than Anabaena flos-aquae. The uptake of dichlobenil was best fit to a pseudo-first order rate kinetic. The specific uptake rate constants of dichlobenil in case of Ankistrodesmus acicularis were considerably lower than the corresponding rates exhibited by Anabaena flos-aquae.  The half- life time for a given concentrations of dichlobenil was at variance for both algal species. Such variation in the uptake rates and half- life time of dichlobenil for both algal species could have some implications on the aquatic ecosystem.