392 research outputs found
The Ghana Cocoa Board (COCOBOD) approved insecticides, imidacloprid, thiamethoxam and bifenthrin, for the control of cocoa mirids (Hemiptera: Miridae): Implications for insecticide-resistance development in Distantiella theobroma (Dist.) and Sahlbergella
The Ghana Cocoa Board (COCOBOD) in 2001 initiated a national Cocoa Diseases and Pest Control (CODAPEC) programme (popularly known as mass-spraying programme) against the cocoa mirids (Hemiptera: Miridae), which are predominantly Distantiella theobroma (Dist.) and Sahlbergella singularis Hagl. The insecticides approved by COCOBOD for controlling the cocoa mirids under CODAPEC and for individual farmer applications are Confidor® (imidacloprid 200 g/l), Actara® (thiamethoxam 240 g/l) and Akate Master® (bifenthrin 27 g/l). Imidacloprid and thiamethoxam are both neonicotinoid insecticides with cross-resistance between them, while cross-resistance has been established between the neonicotinoids and bifenthrin, a pyrethroid insecticide. Using imidacloprid, thiamethoxam and bifenthrin singly or rotationally selects for genes that confer resistance to the approved insecticides. The detection of ɣ-BHC-resistant D. theobroma in Ghana after widespread use of the insecticide against mirids from the mid 1950s through early 1960s indicated the genetic ability of mirids to develop resistance to insecticides. The mass-spraying of imidacloprid, thiamethoxam or bifenthrin to control mirids is, therefore, increasing selection pressure on field populations of mirids, and escalating the risk of the mirids developing resistance to all three insecticides. Preventing resistance development in the cocoa mirids to the COCOBOD approved insecticides is crucial to avert resistance associated yield losses, reduce the risk of insecticide residues in cocoa beans and safeguards Ghana's foreign exchange earnings from cocoa. Measures for protecting imidacloprid, thiamethoxam and bifenthrin from mirid resistance development are recommended
Gendered patterns of IMT adoption and use: Learning from action research
This paper illustrates the value of using an action research methodology to improve understanding of gendered patterns of adoption and non-adoption of Intermediate Means of Transport (IMTs) and similar gender-related transport issues. It presents results from a novel action research project undertaken in five farming villages in southern Ghana, a region where IMT usage is currently low. The participatory action research study not only revealed important issues around differences between stated preferences and actual gendered patterns of adoption and non-adoption in the particular context of southern Ghana, but offers a methodology which may have value in many other gender and transport contexts across sub-Saharan Africa and beyond
2D Electrical Resistivity Tomography (ERT) Survey using the Multi-Electrode Gradient Array at the Bosumtwi Impact Crater, Ghana
The 10.5 km diameter Bosuntwi impact crater in Ghana is occupied by a lake of about 8.5 km in diameter. The multi-electrode gradient array has been used to carry out 2D electrical resistivity tomography (ERT) survey at different locations around the crater. The 2 m take-out cable of the ABEM LUND Resistivity Imaging System was modified to function as a 5 m take-out. 2D electrical resistivity survey was carried out along six (6) radial profiles running from the shore of the lake towards the crater rim. The least-square inversion technique was used to invert the topographically corrected data. The area extending from the lake shore towards the crater rim contains essentially three formations: the low resistivity regions from the shore of the lake towards uphill with resistivities < 64 W.m representing the lake sediments; the moderately high resistivity regions with values between 128 and 200 W.m interpreted as impact related breccias such as dikes, allochthonous or parautochthonous depending on their geometries; lastly, the model clearly differentiates the resistive basement metamorphic rocks of resistivities > 128 W.m from the lake sediments and the breccias due to their geometry and lateral extent. The ERT models allowed us to locate faults and fractures and also the thickness of the post impact lake sediments and the breccias. The results showed that the cables take-outs of the multi-core cable can be modified to suit the requirements of a particular survey thus highlighting the utility of this technique in impact cratering studies and geo-electrical imaging studies in general. Keywords: impact crater, target rock, electrical resistivity tomography (ERT), multi-electrode gradient array, roll-along techniqu
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The influence of shade and organic fertilizer treatments on the physiology and establishment of Theobroma cacao clones
Aims: This experiment aimed to determine whether the soil application of organic fertilizers can help the establishment of cacao and whether shade alters its response to fertilizers.
Study Design: The 1.6 ha experiment was conducted over a period of one crop year (between April 2007 and March 2008) at the Cocoa Research Institute of Ghana. It involved four cacao genotypes (T 79/501, PA 150, P 30 [POS] and SCA 6), three shade levels (‘light’, ‘medium’ and ‘heavy’) and two fertilizer treatments (‘no fertilizer’, and ‘140 kg/ha of cacao pod husk ash (CPHA) plus poultry manure at 1,800 kg/ha). The experiment was designed as a split-plot with the cacao genotypes as the main plot factor and shade x fertilizer combinations as the sub-plots.
Methodology: Gliricidia sepium and plantains (Musa sapientum) were planted in different arrangements to create the three temporary shade regimes for the cacao. Data were collected on temperature and relative humidity of the shade environments, initial soil nutrients, soil moisture, leaf N, P and K+ contents, survival, photo synthesis and growth of test plants.
Results: The genotypes P 30 [POS] and SCA 6 showed lower stomatal conductance under non-limiting conditions. In the rainy seasons, plants under light shade had the highest CO2 assimilation rates. However, in the dry season, plants under increased shade recorded greater photosynthetic rates (P = .03). A significant shade x fertilizer interaction (P = .001) on photosynthesis in the dry season showed that heavier shade increases the benefits that young cacao gets from fertilizer application in that season. Conversely, shade should be reduced during the wet seasons to minimize light limitation to assimilation.
Conclusion: Under ideal weather conditions young cacao exhibits genetic variability on stomatal conductance. Also, to optimize plant response to fertilizer application shade must be adjusted taking the prevailing weather condition into account
An Assessment of Scholarly Contributions and Web Visibility among Scientists of CSIR-Building and Road Research Institute, Ghana
The introduction of the internet has revolutionized the dissemination and assessment of research outputs with renewed emphasis on the impact of scholarly publications. The purpose of this study was to measure scholarly presence and citation impact of research scientists of the Building and Road Research Institute (CSIR-BRRI) on the internet. Bibliometrics was employed as a quantitative research method for this study using Google Scholar. The results showed that majority (77.5%) of scientists had at least one scholarly reference on the internet. It also found that, almost all (96.5%) scientists who had scholarly works online showed affiliation to the CSIR-BRRI. Again, it was observed that most mentions/hits were journal publications (59%) followed by thesis (35%). However, the study found that there was a weak positive relationship between number of journal articles and citations online, a clear indication that a web presence does not automatically reflect the usefulness of a scholarly output. It is recommended that scientists identify and research into globally relevant topics and also publish in reputable journals to enhance their visibility
What More Can Be Done? Childhood Obesity in Glassboro, NJ
Childhood obesity is a growing public health concern in the United States, with an estimated 20% of American children being obese. In New Jersey (NJ), 9% of high school students are obese, and there are disparities in obesity rates based on gender, sexual identity, and race/ethnicity. In Gloucester County, NJ, limited data is available on childhood obesity rates, but 36.4% of adults are obese, and lower SES is related to higher rates of obesity in youth. To address this issue, this research poster proposes a partnership with the Boys and Girls Club of Glassboro to provide nutritional resources and create monthly newsletters for parents and guardians, with the aim of promoting access to affordable produce and grocery stores in the area. This intervention could potentially help reduce rates of childhood obesity in Glassboro, NJ. Limitations of the study include limited data availability and difficulty in finding meaningful and sustainable intervention ideas
Precipitable Water Comparisons Over Ghana using PPP Techniques and Reanalysis Data
Atmospheric Water vapor is an important greenhouse gas and contributes greatly in maintaining the Earth’s energy balance. This critical meteorological parameter is not being sensed by any of the 22 synoptic weather stations in Ghana. This study presents a highly precise tool for water vapor sensing based on the concept Global Navigation Satellite Systems (GNSS) meteorology and tests the computed results against global reanalysis data. Conventional approaches used to sense the atmospheric water vapor or Precipitable Water (PW) such as radiosondes, hygrometers, microwave radiometers or sun photometers are expensive and have coverage and temporal limitations. Whereas GNSS meteorological concept offers an easier, inexpensive and all-weather technique to retrieve PW or Integrated Water Vapor (IWV) from zenith tropospheric delays (ZTD) over a reference station. This study employed precise point positioning (PPP) techniques to quantify the extend of delays on the signal due to the troposphere and stratosphere where atmospheric water vapor resides. Stringent processing criteria were set using an elevation cut-off of 5 degrees, precise orbital and clock products were used as well as nominal tropospheric corrections and mapping functions implemented. The delays which are originally slanted are mapped unto the zenith direction and integrated with surface meteorological parameters to retrieve PW or IWV. The gLAB software, Canadian Spatial Reference System (CSRS) and Automatic Precise Positioning Service (APPS) online PPP services were the approaches used to compute ZTD. PW values obtained were compared with Japanese Metro Agency Reanalysis (JRA), European Centre for Medium-Range Weather Forecasts Reanalysis (ERA-interim) and National Center for Environmental Prediction (NCEP) global reanalysis data. Correlation analysis were run on the logged station data using the three approaches and global reanalysis data. The obtained results show stronger correlation between the retrieved PW values and those provided by the ERA-interim. Finally, the study results indicate that with a more densified network of GNSS base stations the retrieved PW or IWV will greatly improve numerical weather predictions in Ghana.Keywords: GNSS Signals, PPP, Integrated Water vapour, Precipitable Water, Reanalysis Model
Bond Characteristics of Deformed Steel Rebar in Palm Kernel Shell (PKS)-Rubberised Concrete Composite
The bond mechanism between concrete and steel is an important input parameter in the design of reinforced concrete elements. The reuse of waste materials as aggregates in concrete has led to the discovery of different types of concrete with unique bond characteristics. This paper reports on the bond characteristics of concrete produced from waste automobile tire chips and palm kernel shell aggregates and deformed mild steel rebars. A total of 125 concrete cubes (150 x 150 x 150mm) with metal inserts were cast from 21 concrete mixes with varied content of PKS and waste automobile tire aggregates. Pullout test was carried out to evaluate the strength of the bond mechanism between the steel and the various concrete mixes. The results revealed that bond strength decreased with increasing PKS and tire content. Moreover, increasing the bar size and embedment length reduced the bond stress. The ratio of the bond stress and compressive strength was found to be averagely 63.88%. Regarding the bond failure mechanism, it was identified that failure of the specimen occurred through either rebar pullout or tensile splitting of the concrete. Based on the results obtained, it was concluded that PKS and tire can be used as partial replacement of granite aggregates in concrete since the resultant concrete can develop adequate bond with steel bars in structural applications
Incipient bifenthrin-resistance in field populations of cocoa mirids, Distantiella theobroma (Dist.) and Sahlbergella singularis Hagl. (Hemiptera: Miridae)
Bifenthrin is one of the insecticides approved by the Ghana Cocoa Board (COCOBOD) for the control of cocoa mirids. Bifenthrin-resistance levels of D. theobroma and S. singularis collected from different locations in the Eastern Region (ER), Volta Region (VR) and Central Region (CR) were determined by calculating their resistance ratios (RRs). The highest RRs for S. singularis were recorded from New Tafo in the ER and Logba Alikpati in the VR, which displayed 6-fold and 6.2- fold bifenthrin-resistance, respectively. Populations of S. singularis from Pankese in the ER and Likpe in the VR also displayed 3.6-fold and 3.9-fold bifenthrin-resistance, respectively. The D. theobroma population that displayed the highest bifenthrin-resistance of 3.7-fold was from New Tafo. The results show incipient bifenthrin-resistance in field populations of D. theobroma and S. singularis, which requires the implementation of effective resistance management strategies to prevent full-blown resistance in the cocoa mirids
INSECTICIDE HANDLING IN COCOA PRODUCTION IN FOUR REGIONS IN GHANA
Management of insect pests of cocoa (Theobroma cacao L.) using insecticides began in 1950 and has since gone through various programmes with concomitant challenges and successes. Presently Imidacloprid (Confidor®), Bifenthrin (Akatemaster®) and Thiamethoxam (Actara®)are recommended by Ghana Cocoa Board (COCOBOD) for the management of insect pests. A survey was conducted in the Ashanti, Eastern, Volta and Western Regions of Ghana using questionnaires and farm visits of 147 cocoa farmers’ fields to gather information on the characteristics of the farmers and insecticide handling and use by respondents. The survey showed that males dominated cocoa farming (72.7%) and most of them aged between 50 and 60 years. About 44% have had basic education whilst 37.5% of them belonged to farmer based organizations. About 52.8% of the farmers own motorized mistblower but 47.2% of the farmers use knapsack in the absence of a mistblower. About 44.8% do their own spray application whereas 55.2% hire labour. About 60.9% of the population across the regions read the label on the insecticides before application. A few (31.6 %) of the respondents put on the full personal protective costume during insecticide application and 21.9% do not use any protection. There was a positive correlation between farmers’ membership of farmer-based organisation and the costume-wearing farmers in the Ashanti, Eastern and Volta Regions and it was significant in the Ashanti region. It isrecommended that training and monitoring programmes be organized for farmers on the need to handle pesticides properly for personal and environmental safety and consumer benefit.Keywords: Insecticides; pest management; cocoa farmers; safet
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