scholarly journals Identifying cultural, climatic and temporal factors influencing Striga asiatica abundance within rice--maize systems in mid-west Madagascar

Author(s):  
Donald Scott ◽  
Julie Scholes ◽  
Meva Randrianjafizanaka ◽  
Patrice Autfray ◽  
Jean Randriamampianina ◽  
...  

The parasitic weed genus Striga causes huge losses to crop production in sub-Saharan Africa, estimated to be in excess of $7 billion per year, affecting subsistence farmers who frequently lack access to novel technologies proposed for control. Effective Striga management therefore requires the development of strategies utilising existing cultural and management practices. We report a multi-year, landscape-scale monitoring project for Striga asiatica in the mid-west of Madagascar, undertaken over 2019-2020 with the aims of examining cultural, climatic and edaphic factors currently driving abundance and distribution. Long-distance transects were established across the middle-west region of Madagascar, over which Striga asiatica abundance in fields was estimated. Analysis of the data highlights the importance of crop variety and legumes in driving Striga density. Moreover, the dataset revealed significant effect of precipitation seasonality, mean temperature and altitude in determining abundance. A composite management index indicated the effect of a range of cultural practices on changes in Striga abundance. The findings support the assertion that single measures are not sufficient for the effective, long-term management of Striga. Furthermore, the composite score has potential as a significant guide of ISM control beyond the geographic range of this study.

2021 ◽  
Vol 13 (3) ◽  
pp. 1158
Author(s):  
Cecilia M. Onyango ◽  
Justine M. Nyaga ◽  
Johanna Wetterlind ◽  
Mats Söderström ◽  
Kristin Piikki

Opportunities exist for adoption of precision agriculture technologies in all parts of the world. The form of precision agriculture may vary from region to region depending on technologies available, knowledge levels and mindsets. The current review examined research articles in the English language on precision agriculture practices for increased productivity among smallholder farmers in Sub-Saharan Africa. A total of 7715 articles were retrieved and after screening 128 were reviewed. The results indicate that a number of precision agriculture technologies have been tested under SSA conditions and show promising results. The most promising precision agriculture technologies identified were the use of soil and plant sensors for nutrient and water management, as well as use of satellite imagery, GIS and crop-soil simulation models for site-specific management. These technologies have been shown to be crucial in attainment of appropriate management strategies in terms of efficiency and effectiveness of resource use in SSA. These technologies are important in supporting sustainable agricultural development. Most of these technologies are, however, at the experimental stage, with only South Africa having applied them mainly in large-scale commercial farms. It is concluded that increased precision in input and management practices among SSA smallholder farmers can significantly improve productivity even without extra use of inputs.


Agriculture ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 338
Author(s):  
Charity M. Wangithi ◽  
Beatrice W. Muriithi ◽  
Raphael Belmin

The invasive fruit fly Bactrocera dorsalis poses a major threat to the production and trade of mango in sub-Saharan Africa. Farmers devise different innovations to manage the pest in an attempt to minimize yield loss and production costs while maximizing revenues. Using survey data obtained from Embu County, Kenya, we analyzed farmers’ knowledge and perception as regards the invasive fruit fly, their innovations for the management of the pest, and the determinants of their adoption and dis-adoption decisions of recently developed and promoted integrated pest management (IPM) technologies for suppression of the pest. The results show that farmers consider fruit flies as a major threat to mango production (99%) and primarily depend on pesticides (90%) for the management of the pest. Some farmers (35%) however use indigenous methods to manage the pest. Though farmers possess good knowledge of different IPM strategies, uptake is relatively low. The regression estimates show that continued use of IPM is positively associated with the gender and education of the household head, size of a mango orchard, knowledge on mango pests, training, contact with an extension officer, and use of at least one non-pesticide practice for fruit fly management, while IPM dis-adoption was negatively correlated with the size of the mango orchard, practice score and use of indigenous innovations for fruit fly management. We recommend enhancing farmer′s knowledge through increased access to training programs and extension services for enhanced adoption of sustainable management practices for B. dorsalis.


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.


Author(s):  
Chinedu Egbunike ◽  
Nonso Okoye ◽  
Okoroji-Nma Okechukwu

Climate change is a major threat to agricultural food production globally and locally. It poses both direct and indirect effects on soil functions. Thus, agricultural management practices has evolved to adaptation strategies in order to mitigate the risks and threats from climate change. The study concludes with a recommendation the coconut farmers should explore the idea of soil biodiversity in a bid to mitigate the potential negative impact of climate related risk on the farming. The study proffers the need for adopting sustainable agricultural practices to boost local coconut production. This can contribute to the simultaneous realisation of two of the Sustainable Development Goals (SDGs) of the United Nations: SDG 2 on food security and sustainable agriculture and SDG 13 on action to combat climate change and its impacts. The study findings has implications for tackling climate change in Sub-Saharan Africa and in particular Nigeria in order to boost local agricultural production and coconut in particular without negative environmental consequences and an ability to cope with climate change related risks.


Author(s):  
Beza Shewangizaw Woldearegay ◽  
Anteneh Argaw ◽  
Tesfaye Feyisa ◽  
Birhan Abdulkadir ◽  
Endalkachew Wold-Meskel

In sub-Saharan Africa, multiple plant nutrients deficiency besides nitrogen (N) and phosphorus (P) is a major growth-limiting factor for crop production. As a result, some soils become non-responsive for Rhizobium inoculation besides P application. Based on the soil test result, the soil of Experimental sites had low organic matter (OM), nitrogen (N), phosphorus (P), sulphur (S) and zinc (Zn)[xy1]. Hence, an experiment was carried out on-farm at Gondar Zuria woreda in Tsion and Denzaz Kebeles to evaluate the effect of Rhizobium inoculation, S and Zn application on yield, nodulation, N and P uptake of chickpea. The experiment included twelve treatments developed via factorial combination of two level of inoculation (Rhizobium inoculated, un-inoculated), three level of S (0, 15, 30 kg Sulphur ha-1) and two levels of Zn (0, 1.5 kg Zinc ha-1). The treatment was laid out in randomized complete block design with three replications. Results showed that the highest mean nodule number (15.3) and nodule volume (1.3 ml plant-1) over locations were obtained with Rhizobium inoculation integrated with 15 kg S and 1.5 kg Zn ha-1 which resulted in 37.8% and 116.7% increment over the control check, respectively. It was also observed that combined application of Rhizobium and 30 kg S ha-1 caused the highest (6.7) mean nodulation rating and seed yield (1775.5 kg ha-1) over locations which resulted in 86.1% and 28 % increase over the control check, respectively. Moreover, this treatment improved P use efficiency of chickpea. On the bases of observed result, it can be concluded that the response of chickpea to Rhizobium and P application can be improved by S application and Rhizobium inoculation with application of 30 kg S ha-1 with recommended rate of P and starter N is recommended for chickpea production at the experimental locations in Gonder Zuria Woreda.


Food Security ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 105-135 ◽  
Author(s):  
Marcin Pawel Jarzebski ◽  
Abubakari Ahmed ◽  
Yaw Agyeman Boafo ◽  
Boubacar Siddighi Balde ◽  
Linda Chinangwa ◽  
...  

2018 ◽  
Vol 19 (5) ◽  
pp. 537-553 ◽  
Author(s):  
Emmanuel Addo Sowatey ◽  
Justice Tankebe

Much of our methodological insights from researching policing in sub-Saharan Africa comes from studies of frontline officers. Consequently, many important methodological questions about research on senior police officers remain unanswered. This article addresses this gap by drawing on insights from interviewing senior officers in Ghana. It focuses on the challenges and opportunities in negotiating access, establishing trust during interviews and dealing with ethical dilemmas. We highlight the role of informal social networks and cultural practices of surprise visits, what we have termed strategic ambush, in securing formal approval for our research. However, this represented mere or putative access for which deference towards institutional gatekeepers was key to its actualization. Deference towards officers and extensive knowledge of the policing environment helped to put the senior officers at ease, and enhanced the chances of a successful interview. Finally, we offer reflections on our responses to unexpected ethical dilemmas that we faced in the field.


1996 ◽  
Vol 25 (3) ◽  
pp. 157-164 ◽  
Author(s):  
Dana Berner ◽  
Robert Carsky ◽  
Kenton Dashiell ◽  
Jennifer Kling ◽  
Victor Manyong

Striga hermonthica, an obligate root parasite of grasses, Is one of the most severe constraints to cereal production in sub-Saharan Africa. In the recent past, prior to increased production pressure on land, S. hermonthica was controlled in African farming systems by prolonged crop rotations with bush fallow. Because of increasing need for food and concomitant changes in land management practices, however, these fallow rotations are no longer extensively used. Shorter crop rotations and fallow periods have also led to declines in soil fertility which present a very serious threat to African food production. A sustainable solution will be an integrated approach that simultaneously addresses both of these major problems. An integrated programme that replaces traditional bush fallow rotation with non-host nitrogen-fixing legume rotations, using cultivars selected for efficacy in germinating S. hermonthica seeds, is outlined. The programme includes use of S. hermonthlca-free planting material, biological control, cultural control to enhance biological suppressiveness, host-plant resistance, and host-seed treatments.


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