scholarly journals Food Security, Fertility Differentials and Land Degradation in Sub-Saharan Africa: A Dynamic Framework

2021 ◽  
Vol 1 ◽  
pp. 1-22
Author(s):  
Maria Winkler-Dworak
Insects ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 260
Author(s):  
Habibu Mugerwa ◽  
Peter Sseruwagi ◽  
John Colvin ◽  
Susan Seal

In East Africa, the prevalent Bemisia tabaci whiteflies on the food security crop cassava are classified as sub-Saharan Africa (SSA) species. Economically damaging cassava whitefly populations were associated with the SSA2 species in the 1990s, but more recently, it has been to SSA1 species. To investigate whether biological traits (number of first instar nymphs, emerged adults, proportion of females in progeny and development time) of the cassava whitefly species are significant drivers of the observed field abundance, our study determined the development of SSA1 sub-group (SG) 1 (5 populations), SG2 (5 populations), SG3 (1 population) and SSA2 (1 population) on cassava and eggplant under laboratory conditions. SSA1-(SG1-SG2) and SSA2 populations’ development traits were similar. Regardless of the host plant, SSA1-SG2 populations had the highest number of first instar nymphs (60.6 ± 3.4) and emerged adults (50.9 ± 3.6), followed by SSA1-SG1 (55.5 ± 3.2 and 44.6 ± 3.3), SSA2 (45.8 ± 5.7 and 32.6 ± 5.1) and the lowest were SSA1-SG3 (34.2 ± 6.1 and 32.0 ± 7.1) populations. SSA1-SG3 population had the shortest egg–adult emergence development time (26.7 days), followed by SSA1-SG1 (29.1 days), SSA1-SG2 (29.6 days) and SSA2 (32.2 days). Regardless of the whitefly population, development time was significantly shorter on eggplant (25.1 ± 0.9 days) than cassava (34.6 ± 1.0 days). These results support that SSA1-(SG1-SG2) and SSA2 B. tabaci can become highly abundant on cassava, with their species classification alone not correlating with observed abundance and prevalence.


1994 ◽  
Vol 23 (3) ◽  
pp. 197-205 ◽  
Author(s):  
Felix Izu Nweke

Cassava makes an important contribution to improving food security and rural incomes in sub-Saharan Africa, as it is tolerant of drought and poor soil and its cultivation does not require much labour. However, the fresh roots are bulky and perishable and need to be processed before they can be marketed; processing also removes the cyanogens which make many varieties poisonous in their raw form. Cassava roots are turned into granules, flours, pastes and chips, with a wide range of flavours and appearances for different areas and markets. Many different processing techniques are used, some of which make intensive use of fuelwood while others require a plentiful water supply. These requirements, as well as the need for a good transport and marketing infrastructure, limit the expansion of cassava production in sub-Saharan Africa, but technical solutions are being found.


2017 ◽  
Vol 5 (1) ◽  
pp. 50
Author(s):  
Kalifa TRAORE ◽  
Daouda SIDIBE ◽  
Harouna COULIBALY

Climate variability and change are recognized as the greatest challenge to crop production and food security in sub-Saharan Africa. This work assesses farmers’ perception on the contribution of improved varieties of sorghum and millet in the search for food security in Cinzana rural commune of Mali in the current context of climate change.The methodology was based on focus group surveys with both, the decentralized technical services, administrative and municipal authorities, NGOs, farmer organizations and producers but also farmer exchanges visits on improved varieties tested in farmer’s field.The result shows that climate change is described by the majority of farmers (87%) as decrease in rainfall amount and length of rainy seasons, high increases in temperature and high deforestation and water scarcity. Unpredictability of climate, (80%), drought (70%) and heavy rain (65%) occurrence were identified as major perception of farmers on risks in climate for crop production and soil degradation. After farmers’ study tour, 80% of the participants mentioned a better growth of plants and increase of soil moisture with the use of contour ridges tillage as a water conservation technology. Adapted cycle (55%) and higher yield (37%) of improved varieties were farmer’s main drivers for adoption of improved millet and sorghum varieties.The study revealed that local farmers have substantial knowledge on climate variabilities and risks and also are aware of some adaptation strategies. However, for wide scale adoption of effective strategies, capacity strengthening appeared a prerequisite.


2010 ◽  
Vol 107 (46) ◽  
pp. 19661-19666 ◽  
Author(s):  
C. A. Palm ◽  
S. M. Smukler ◽  
C. C. Sullivan ◽  
P. K. Mutuo ◽  
G. I. Nyadzi ◽  
...  

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