scholarly journals An evaluation of the efficacy of extracts from Xylopia aethiopica and Dennittia tripetala in controlling Dermestes maculatus(degeer) an insect pest of dry stored fish in Calabar, Nigeria

2021 ◽  
Vol 10 (1) ◽  
pp. 1-6
Author(s):  
Fidelis Bekeh Ada
Keyword(s):  
Essential Oils ◽  
Adult Population ◽  
Insect Pest ◽  
Chemical Constituent ◽  
College Of Education ◽  
Sub Saharan Africa ◽  
Small Scale ◽  
Local Market ◽  
Sub Saharan ◽  
Xylopia Aethiopica

Laboratory bioassays were conducted in Obudu, Nigeria to evaluate the efficacy of extracts from X.aethiopica and D.tripetala in controlling D.maculatus a primary pest of dry stored fish in sub-saharan Africa. Adult population of D. maculatus was obtained in the laboratory at the Federal college of Education Obudu, to obtain fresh insects for the experimental work. Dried fruits of X.aethiopica (Dunal) and dried seeds of D.tripetala (Bak.f.) were procured from a local market in Obudu for the purpose of the work. 100g each of the spice plants were pounded separately using laboratory pestle and mortar for the extraction of essential oils (EOS). The essential oils extracted were tested for repellence and toxicity against D.maculatus at 10µl per EO in a 4-way Olfactometer. Minitab 15 statistical soft ware was used for the analysis of data. Results indicated that the essential oils (EOS) and their constituent individual compounds were significantly (p<0.05) repellent and toxic to D.maculatus with X.aethiopica more repellent and more toxic to the insect than D.tripelala. The two oils were also observed to inhibit the activities of microbes that usually cause and accelerate delaying in stored fish. This action of the essential oils of the two spice plants and their chemical constituent demonstrated their potentials for development in stored products protection, especially at the small scale resource poor farmer’s level in Nigeria.

scholarly journals Comparative analysis of the repellency activity of single compounds and the synthetic blends of semiochemicals from Aframomum melegueta (R.schum) and Dennittia tripetala (Bak.F) against Rhizopertha dominica in Calabar, Nigeria

2021 ◽  
Vol 1 (2) ◽  
pp. 59-69
Author(s):  
Lawrence Ugbe
Keyword(s):  
Essential Oils ◽  
Insect Pests ◽  
Chemical Constituents ◽  
Insect Pest ◽  
Research Work ◽  
Reproductive Potential ◽  
Sub Saharan Africa ◽  
Small Scale ◽  
Rhizopertha Dominica ◽  
Repellency Activity

Bioassay experiments were carried out in Calabar to compare the repellency activity of single compounds and the synthetic blends of Semiochemicals extracted from Afromomum melegueta and Dennittia tripetala. The aim of the experiment was to determine the efficacy of single compounds and the synthetic blends in suppressing the reproductive potential and adult emergence of Rhizopertha dominica, (Fabricius), a primary pest of stored cassava pellets and cereal grains in Sub-Saharan Africa. Insect culture of the adult R. dominica was set up in the laboratory at Federal College of Education Obudu to obtain fresh insects for the bioassay experiments. Dried seeds of A. melegueta (R. Schum) and D. tripetala (Baker f.) Schatz were procured from the main market in Obudu for the purpose of the research work. 100g each of the dried fruits of the spice plants were pounded separately with the laboratory pestle and mortar for the extraction of the essential oils (EOs). The oils extracted were tested for toxicity and reproductive potential deterrence against R. dominica. The chemical constituents of the essential oils were isolated, identified and tested against R. dominica. Synthetic blends of individual compounds were prepared based on their natural ratios and were also tested for toxicity and reproductive potential deterrence against the insect pests in the laboratory. The result showed that both the single compounds and the synthetic blends were toxic and repellent to the insect pest, and could significantly suppress the reproductive potential thereby inhibiting the emergence of adult insect. However, synthetic blends exhibited a stronger efficacy in their toxicity against the pest thereby providing a broad spectrum of insecticidal bioactivity against R. dominica than the single compounds. This action of the synthetic blends of extracts from the spice plants demonstrated their potential for development in stored products protection especially at the small scale resource poor farmer’s level in Nigeria.

scholarly journals The toll of COVID-19 on African children: A descriptive analysis on the COVID-19-related morbidity and mortality among the pediatric population in Sub-Saharan Africa

2021 ◽  
Author(s):  
Sabina Rodriguez Velasquez ◽  
Lea Jacques ◽  
Jyoti Dalal ◽  
Paolo Sestito ◽  
Zahra Habibi ◽  
...  
Keyword(s):  
Cumulative Incidence ◽  
Pediatric Population ◽  
Adult Population ◽  
Age Groups ◽  
Sub Saharan Africa ◽  
Morbidity And Mortality ◽  
African Countries ◽  
Regional Office ◽  
Sub Saharan ◽  
Epidemiological Characteristics

Introduction: Since the beginning of the COVID-19 pandemic, very little data on the epidemiological characteristics among the pediatric population in Africa has been published. This paper examines the age and sex distribution of the morbidity and mortality rate in children with COVID-19 and compares it to the adult population within 15 Sub-Saharan African countries. Methods: A merge line listing dataset using a reverse engineering model shared by countries within the Regional Office for Africa was analyzed. Patients diagnosed within 1 March 2020 and 1 September 2020 with confirmed positive RT-PCR test for SARS-CoV-2 were analyzed. Children data were stratified into three age groups: 0-4 years, 5-11 years, and 12-17 years, while adults were combined. The cumulative incidence of cases including its medians and 95% confidence intervals were calculated. Results: 9% of the total confirmed cases and 2.4% of the reported deaths were pediatric cases. The 12-17 age group in all 15 countries showed the highest cumulative incidence proportion in children. COVID-19 cases in males and females under the age of 18 were evenly distributed. Among adults, a higher case incidence per 100,000 people was observed compared to children. Conclusion: The cases and deaths within the children population was smaller than the adult population. These differences can reflect biases in COVID-19 testing protocols and reporting implemented by countries, highlighting the need for more extensive investigation and focus on the effects of COVID-19 in children.

scholarly journals Shallow groundwater in sub-Saharan Africa: neglected opportunity for sustainable intensification of small-scale agriculture?

2016 ◽  
Author(s):  
John Gowing ◽  
Geoff Parkin ◽  
Nathan Forsythe ◽  
David Walker ◽  
Alemseged Tamiru Haile ◽  
...  
Keyword(s):  
Groundwater Resources ◽  
Climatic Variability ◽  
Shallow Groundwater ◽  
Sustainable Intensification ◽  
Sub Saharan Africa ◽  
Small Scale ◽  
Groundwater Levels ◽  
Sub Saharan ◽  
Small Scale Irrigation

Abstract. There is a need for an evidence-based approach to identify how best to support development of groundwater for small scale irrigation in sub-Saharan Africa (SSA). We argue that it is important to focus this effort on shallow groundwater resources which are most likely to be used by poor rural communities in SSA. However, it is important to consider constraints, since shallow groundwater resources are likely to be vulnerable to over-exploitation and climatic variability. We examine here the opportunities and constraints and draw upon evidence from Ethiopia. We present a methodology for assessing and interpreting available shallow groundwater resources and argue that participatory monitoring of local water resources is desirable and feasible. We consider possib le models for developing distributed small-scale irrigation and assess its technical feasibility. Because of power limits on water lifting and also because of available technology for well construction, groundwater at depths of 50 m or 60 m cannot be regarded as easily accessible for small-scale irrigation. We therefore adopt a working definition of shallow groundwater as < 20 m depth. This detailed case study in the Dangila woreda in Ethiopia explores the feasibility of exploiting shallow groundwater for small-scale irrigation over a range of rainfall conditions. Variability of rainfall over the study period (9 % to 96 % probability of non-exceedance) does not translate into equivalent variability in groundwater levels and river baseflow. Groundwater levels, monitored by local communities, persist into the dry season to at least the end of December in most shallow wells, indicating that groundwater is available for irrigation use after the cessation of the wet season. Arguments historically put forward against the promotion of groundwater use for agriculture in SSA on the basis that aquifers are unproductive and irrigation will have unacceptable impacts on wetlands and other groundwater-dependent ecosystems appear exaggerated. It would be unwise to generalise from this case study to the whole of SSA, but useful insights into the wider issues are revealed by the case study approach. We believe there is a case for arguing that shallow groundwater in sub-Saharan Africa represents a neglected opportunity for sustainable intensification of small-scale agriculture.

scholarly journals Reform of irrigation management and investment policy in African development

2004 ◽  
Vol 7 (4) ◽  
pp. 652-663 ◽  
Author(s):  
KW Easter ◽  
S Zekri
Keyword(s):  
Irrigation Management ◽  
Investment Strategy ◽  
Sub Saharan Africa ◽  
Small Scale ◽  
Small Farm ◽  
Irrigation Development ◽  
Farm Productivity ◽  
Sub Saharan ◽  
Direct Government ◽  
Small Scale Irrigation

This paper examines the reform of water and irrigation management in Africa and compares it with similar reforms in Asia.  Several things are evident from the review.  First, Sub-Saharan Africa (SSA) is at an earlier stage of irrigation development and reform than Asia.  Second, the articulated need for reform is much stronger in Asia than it is in SSA.  Third, the productivity of small-scale irrigated farms is significantly lower in SSA compared to Asia.  Thus any irrigation investment strategy in SSA should be different from Asia and focus on increasing small-farm productivity as well as small-scale irrigation projects.  Finally, all direct government irrigation investments should be done jointly with decisions regarding the type of project management.

scholarly journals The national determinants of deforestation in sub-Saharan Africa

2013 ◽  
Vol 368 (1625) ◽  
pp. 20120405 ◽  
Author(s):  
Thomas K. Rudel
Keyword(s):  
Forest Cover ◽  
Driving Forces ◽  
National Level ◽  
Congo Basin ◽  
Sub Saharan Africa ◽  
Small Scale ◽  
Urban Migration ◽  
Forest Cover Change ◽  
Level Data ◽  
Sub Saharan

For decades, the dynamics of tropical deforestation in sub-Saharan Africa (SSA) have defied easy explanation. The rates of deforestation have been lower than elsewhere in the tropics, and the driving forces evident in other places, government new land settlement schemes and industrialized agriculture, have largely been absent in SSA. The context and causes for African deforestation become clearer through an analysis of new, national-level data on forest cover change for SSA countries for the 2000–2005 period. The recent dynamic in SSA varies from dry to wet biomes. Deforestation occurred at faster rates in nations with predominantly dry forests. The wetter Congo basin countries had lower rates of deforestation, in part because tax receipts from oil and mineral industries in this region spurred rural to urban migration, declines in agriculture and increased imports of cereals from abroad. In this respect, the Congo basin countries may be experiencing an oil and mineral fuelled forest transition. Small farmers play a more important role in African deforestation than they do in southeast Asia and Latin America, in part because small-scale agriculture remains one of the few livelihoods open to rural peoples.

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