Long-term maize-Desmodium intercropping shifts structure and composition of soil microbiome with stronger impact on fungal communities

Abstract Purpose Push–pull is an intercropping technology that is rapidly spreading among smallholder farmers in Sub-Saharan Africa. The technology intercrops cereals with Desmodium to fight off stem borers, eliminate parasitic weeds, and improve soil fertility and yields of cereals. The above-ground components of push–pull cropping have been well investigated. However, the impact of the technology on the soil microbiome and the subsequent role of the microbiome on diverse ecosystem benefits are unknown. Here we describe the soil microbiome associated with maize—Desmodium intercropping in push–pull farming in comparison to long-term maize monoculture. Methods Soil samples were collected from long-term maize—Desmodium intercropping and maize monoculture plots at the international centre for insect physiology and ecology (ICIPE), Mbita, Kenya. Total DNA was extracted before16S rDNA and ITS sequencing and subsequent analysis on QIIME2 and R. Results Maize—Desmodium intercropping caused a strong divergence in the fungal microbiome, which was more diverse and species rich than monoculture plots. Fungal groups enriched in intercropping plots are linked to important ecosystem services, belonging to functional groups such as mycorrhiza, endophytes, saprophytes, decomposers and bioprotective fungi. Fewer fungal genera were enriched in monoculture plots, some of which were associated with plant pathogenesis and opportunistic infection in humans. In contrast, the impact of intercropping on soil bacterial communities was weak with few differences between intercropping and monoculture. Conclusion Maize—Desmodium intercropping diversifies fungal microbiomes and favors taxa associated with important ecosystem services including plant health, productivity and food safety.

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Long-Term Maize-Legume Intercropping Shifts Structure and Composition of Soil Microbiome with Potential Impacts on Ecosystem Services and Food Safety

10.21203/rs.3.rs-221776/v1 ◽

2021 ◽

Author(s):

Aneth Mwakilili ◽

Kilaza Samson Mwaikono ◽

Sebastian Larsson Herrera ◽

Charles Midega ◽

Francis Magingo ◽

...

Keyword(s):

Ecosystem Services ◽

Food Safety ◽

Smallholder Farmers ◽

Cropping Systems ◽

Plant Diseases ◽

Soil Microbiome ◽

Fungal Microbiome ◽

Sub Saharan ◽

Decomposer Fungi

Abstract Purpose: Push-pull is an intercropping technology that rapidly spreads among Sub-Saharan smallholder farmers. It intercrops maize with Desmodium to fight off stem borers, eliminate parasitic weeds, and improve soil fertility and yields. The above-ground components of push-pull cropping have been well investigated. However, impact on and from the soil microbiome and its role in diverse ecosystem benefits are unknown. Here we describe the soil microbiome associated with push-pull and compare it with maize monoculture.Methods: Soil samples from long-term maize-desmodium intercropping and maize monoculture plots were analysed using 16S and ITS metagenomics.Results: Maize-desmodium intercropping caused a strong divergence in fungal microbiome, which was more diverse and species rich than monoculture plots. Zooming into genera revealed that intercropping enhanced fungal genera linked to important ecosystem services. These include mycorrhizal and endophytic groups such as Edenia, Acrocalyma and Colletotrichum, saprophytic and decomposer fungi like Pithya and Cristinia and fungi with biocontrol properties, for instance, Talaromyces, Penicillin, Clonostachys and Trichoderma. Fungal genera enriched in monoculture plots were few, and were functionally linked to plant diseases (for example Didymella, Curvularia and Parastagonospora), and human pathogenic taxa (Exserohilum, Curvularia and Aspergillus). Although separating well, bacterial microbiomes did not, except in a few genera, differ between treatments. Conclusion: Maize-desmodium intercropping diversifies fungal microbiomes and favors taxa that are associated with important ecosystem services, including plant health, productivity and food safety. Further studies should increase the resolution of shifts noted above, experimentally ascertain the inferred functions, and translate this knowledge to improve cropping systems.

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Aging, Health, and Quality of Life for Older People Living With HIV in Sub-Saharan Africa: A Review and Proposed Conceptual Framework

Journal of Aging and Health ◽

10.1177/0898264317724549 ◽

2017 ◽

Vol 31 (1) ◽

pp. 109-138 ◽

Cited By ~ 10

Author(s):

Mark J. Siedner

Keyword(s):

Quality Of Life ◽

Conceptual Framework ◽

Care Delivery ◽

Sub Saharan Africa ◽

People Living With Hiv ◽

Sub Saharan ◽

Living With Hiv ◽

The Impact

Objective: The number of people living with HIV (PLWH) over 50 years old in sub-Saharan Africa is predicted to triple in the coming decades, to 6-10 million. Yet, there is a paucity of data on the determinants of health and quality of life for older PLWH in the region. Methods: A review was undertaken to describe the impact of HIV infection on aging for PLWH in sub-Saharan Africa. Results: We (a) summarize the pathophysiology and epidemiology of aging with HIV in resource-rich settings, and (b) describe how these relationships might differ in sub-Saharan Africa, (c) propose a conceptual framework to describe determinants of quality of life for older PLWH, and (d) suggest priority research areas needed to ensure long-term gains in quality of life for PLWH in the region. Conclusions: Differences in traditional, lifestyle, and envirnomental risk factors, as well as unique features of HIV epidemiology and care delivery appear to substantially alter the contribution of HIV to aging in sub-Saharan Africa. Meanwhile, unique preferences and conceptualizations of quality of life will require novel measurement and intervention tools. An expanded research and public health infrastructure is needed to ensure that gains made in HIV prevention and treamtent are translated into long-term benefits in this region.

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African agriculture in the context of COVID-19: Finding salvation in the devil

African Journal of Agricultural and Resource Economics ◽

10.53936/afjare.2020.15(4).19 ◽

2020 ◽

Vol 15 (4) ◽

pp. 302-310

Author(s):

Guy Blaise Nkamleu ◽

Keyword(s):

Agricultural Development ◽

Agricultural Sector ◽

Food System ◽

Free Trade Area ◽

Sub Saharan Africa ◽

African Countries ◽

Agriculture Sector ◽

Sub Saharan ◽

The Impact

The world is facing unprecedented challenges from COVID-19, which is disrupting lives and livelihoods. The pandemic could profoundly affect the African continent and wipe out hard-won development gains, as sub-Saharan Africa heads into its first recession in 25 years. Beyond the multispatial impact of the coronavirus in Africa, its effects on the agriculture and food system is of particular interest, as food security could be the most affected area and, at the same time, agriculture could be the sector that could help African economies recover quicker from the impact of COVID19. This paper supports the view that COVID-19, as devilish as it may be, offers an opportunity to revive interest in the agricultural sector. The COVID-19 pandemic has placed immense pressures on African countries to raise additional resources, and consequently Africa’s growing public debt is again coming back to the centre stage of the global debate. The conversation on African debt sustainability has begun to dominate the scene and will flood the debate in the near term. While the observed, growing calls for debt relief for African countries are legitimate, we support in this paper that one should not divert attention from the long-term solutions needed to strengthen Africa’s resilience. These long-term solutions lie where they always have: in agriculture. With COVID-19, shipping agricultural inputs and food products from other continents to Africa has become disrupted and is accelerating the trend towards shortening supply chains. This will leave a potential market for inputs and food produced on the continent. COVID-19, together with the launching of the African Continental Free Trade Area (AfCFTA), have aligned the stars in favour of a decisive transformation of the agriculture sector on the continent. Agriculturalists and development experts need to be aware of their responsibility at this time, as they need to advocate for the topic of agricultural development to return to the centre and the heart of the agenda of discussions on how to respond to the consequences of Covid-19 in Africa. In this sense, and unexpectedly, COVID-19 is an opportunity for the agricultural sector.

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Les petits exploitants agricoles à l’école inclusive : cas de l’apprentissage collectif par la vidéo et la radio sur la post-récolte du riz local au Bénin

International Journal of Biological and Chemical Sciences ◽

10.4314/ijbcs.v15i4.29 ◽

2021 ◽

Vol 15 (4) ◽

pp. 1678-1697

Author(s):

Espérance Zossou ◽

Seth Graham-Acquaah ◽

John Manful ◽

Simplice D. Vodouhe ◽

Rigobert C. Tossou

Keyword(s):

Smallholder Farmers ◽

Laboratory Data ◽

Innovation System ◽

Collective Learning ◽

Sub Saharan Africa ◽

Quality Analysis ◽

Afrique Subsaharienne ◽

Sub Saharan ◽

Student’S T ◽

The Impact

En Afrique subsaharienne, les petits exploitants agricoles ruraux ont difficilement accès aux connaissances et informations actualisées afin d’améliorer leur revenu. Pour renforcer l’apprentissage collectif au sein des acteurs des chaînes de valeur du riz local blanc et étuvé, la vidéo et la radio ont été utilisées de façon participative. La présente étude visait à comprendre l’influence de cet apprentissage collectif sur (i) le changement des pratiques des transformations et (ii) la qualité du riz local. Des interviews et suivis hebdomadaires ont été réalisés entre 2009 et 2018 au sud et nord du Bénin auprès de 240 transformateurs choisis aléatoirement. Des échantillons de riz ont été également collectés pour des analyses de qualité au laboratoire. L’analyse des données a été faite avec les tests t de Student, Wilcoxon, ANOVA, et le modèle de régression de Poisson. Les résultats ont montré une amélioration des pratiques de 14% ; 23% et 58% respectivement dans les villages contrôles, radio et vidéo. Dans le processus d’amélioration des pratiques, les transformateurs ont renforcé leur créativité en développant des technologies appropriées à leur environnement ; ce qui a eu un impact positif sur les qualités physiques et de cuisson du riz. Dans un contexte de pauvreté, d’insécurité alimentaire, de ruralité et d’analphabétisme, l’apprentissage collectif par la vidéo et la radio locale se révèle être une opportunité pour le renforcement du système d’innovation agricole. English title: Smallholder farmers at inclusive school: Lessons learnt from collective learning through video and radio on local rice processing in Benin In sub-Saharan Africa, rural smallholder farmers have limited access to timely and up-to-date knowledge and information to improve their incomes. To strengthen collective learning among rice sector’ stakeholders, videos and radio were participatory used. This study aims to assess the impact of this collective learning on (i) changing rice processors practices and (ii) the quality of local rice. Interviews and weekly follow-ups were conducted between 2009 and 2018 in southern and northern Benin with 240 randomly selected rice processors. Rice samples were also collected for quality analysis in the laboratory. Data analysis was done with Student's t-tests, Wilcoxon, one-way ANOVA, and the Poisson regression model. The results showed an improvement in rice processors practices of 14%; 23% and 58% respectively in control, video and radio villages. During the improvement of their practices, rice processors have increased their creativity by developing appropriate technologies to their environment; and this has positively impact on the physical and cooking qualities of the rice. In a context of poverty, food insecurity, rurality and illiteracy, collective learning through video and radio seems to be an opportunity to strengthen the agricultural innovation system, and a booster for change through adoption and adaptation of innovation.

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Urban farming in Nairobi: understanding the impact of capacity building on female farmers

10.32920/ryerson.14656578.v1 ◽

2021 ◽

Author(s):

Rebecca Tye

Keyword(s):

Urban Agriculture ◽

Positive Impact ◽

Secondary Data ◽

Sub Saharan Africa ◽

Urban Farming ◽

Global Trends ◽

Female Farmers ◽

Sub Saharan ◽

The Impact

The growth of cities places urbanization as one of the 21st century’s most significant global trends. As urban populations in sub-Saharan Africa increase so do food insecurities. One long-term strategy used by households to improve access to nutritional food is to practice urban agriculture. This raises the question of what the impact might be on cities if urban farmers were better supported through training. This issue is important for women who play a strong role in urban farming. The central goals of this study are to analyze and evaluate the impact of urban agriculture based training on individual women. This study was informed by primary and secondary data. The findings are the result of in-depth qualitative research in Nairobi, Kenya. The research reveals that the urban agriculture training is having a positive impact on female participants. Recommendations to further enhance the impact of training on the female participants are discussed.

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Urban farming in Nairobi: understanding the impact of capacity building on female farmers

10.32920/ryerson.14656578 ◽

2021 ◽

Author(s):

Rebecca Tye

Keyword(s):

Urban Agriculture ◽

Positive Impact ◽

Secondary Data ◽

Sub Saharan Africa ◽

Urban Farming ◽

Global Trends ◽

Female Farmers ◽

Sub Saharan ◽

The Impact

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Policy Integration and Coherence for Conservation Agriculture Initiatives in Malawi

Sustainable Agriculture Research ◽

10.5539/sar.v7n4p51 ◽

2018 ◽

Vol 7 (4) ◽

pp. 51 ◽

Cited By ~ 2

Author(s):

Edna Chinseu ◽

Lindsay Stringer ◽

Andrew Dougill

Keyword(s):

Smallholder Farmers ◽

Innovation System ◽

Conservation Agriculture ◽

Sub Saharan Africa ◽

Policy Integration ◽

Agricultural Policies ◽

Development Agenda ◽

Sub Saharan ◽

Agricultural Innovations

In sub-Saharan Africa, development and dissemination of perceived new agricultural innovations dominate the development agenda yet hunger and poverty remain widespread. A conducive policy environment is essential to support these efforts. Despite that national policies are a critical component in the functioning of an agricultural innovation system, studies have often overlooked their relevance in farmers’ adoption of agricultural innovations. There is an urgent need to enhance understanding of how policies affect long-term adoption of agricultural innovations aimed at increasing productivity and incomes of smallholder farmers. This study utilises thematic content analysis to examine the extent of integration of Conservation Agriculture (CA) and coherence in Malawi’s national agricultural policies, and their implication for CA adoption among smallholder farmers.Results indicate that inadequate integration of CA in the National Agricultural Policy (NAP), coupled with a lack of coherence of agricultural department policies, undermines farmers’ CA adoption. While inadequate integration constrains resource allocation for supporting CA activities, lack of coherence of agricultural policies radiates conflicting and confusing agricultural extension messages to smallholder farmers. We argue that inadequate CA integration and incoherence of policies are institutional constraints which prevent farmers’ sustained adoption. To facilitate long-term adoption of CA among smallholders, there is need to: (1) strengthen CA integration in agricultural policies; (2) improve departmental coordination to enhance coherence of agricultural strategies and extension messages disseminated to farmers; and (3) strengthen government’s role in supporting multi-disciplinary research to generate and disseminate best practices capable of sustaining CA adoption.

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Climate Change and the Future Heat Stress Challenges among Smallholder Farmers in East Africa

Atmosphere ◽

10.3390/atmos11070753 ◽

2020 ◽

Vol 11 (7) ◽

pp. 753

Author(s):

Genesis Tambang Yengoh ◽

Jonas Ardö

Keyword(s):

Climate Change ◽

General Circulation ◽

Smallholder Farmers ◽

General Circulation Models ◽

Sub Saharan Africa ◽

Critical Element ◽

Critical Periods ◽

The Future ◽

Sub Saharan ◽

The Impact

Agricultural production in sub-Saharan Africa remains dependent on high inputs of human labor, a situation associated with direct exposure to daylight heat during critical periods of the agricultural calendar. We ask the question: how is the Wet-Bulb Globe Temperature (WBGT) going to be distributed in the future, and how will this affect the ability of smallholder farmers to perform agricultural activities? Data from general circulation models are used to estimate the distribution of WBGT in 2000, 2050 and 2100, and for high activity periods in the agricultural calendar. The distribution of WBGT is divided into recommended maximum WBGT exposure levels (°C) at different work intensities, and rest/work ratios for an average acclimatized worker wearing light clothing (ISO, 18). High WBGTs are observed during the two periods of the East African. In February to March, eastern and coastal regions of Kenya and Tanzania witness high WBGT values—some necessitating up to 75% rest/hour work intensities in 2050 and 2100. In August to September, eastern and northern Kenya and north and central Uganda are vulnerable to high WBGT values. Designing policies to address this key challenge is a critical element in adaptation methods to address the impact of climate change.

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Rhizobium inoculants suppress emergence of the weed Striga gesnerioides in cowpea

10.21203/rs.3.rs-358536/v1 ◽

2021 ◽

Author(s):

WAJIHA ABDULLAHI MU'AZ ◽

Mahamdi Dianda ◽

Ousmane Boukar ◽

Ibnou Dieng ◽

Gaya S Mohammed ◽

...

Keyword(s):

Smallholder Farmers ◽

Sub Saharan Africa ◽

Yield Response ◽

Grain Legume ◽

Striga Gesnerioides ◽

Rhizobium Inoculation ◽

Resistant Varieties ◽

Sub Saharan ◽

The Impact ◽

Resistant Genotypes

Abstract Cowpea is a grain legume of major importance in sub-Saharan Africa where it is cultivated by smallholder farmers on poor soils and production is often constrained by the parasitic weed Striga gesnerioides. Experiments were conducted to assess the potential of rhizobium inoculation in mitigating Striga infestation and increasing cowpea productivity. We tested under basal P application and artificial S. gesnerioides inoculation the impact of cowpea genotypes (G) (nine Striga-resistant and 11 Striga–susceptible genotypes) and bradyrhizobium inoculation (N) (two bradyrhizobium strains USDA3384 and IRJ2180A, and uninoculated control) on Striga dynamics and cowpea yield. Additional treatments included N supplied as urea (with and without), and no input (i.e., soil inherent N and P) that served as negative check. A first experiment was carried out in potted sterile soils in the screen house excluding addition of N-fertilizers. Significant G x N interactions were observed in counts of nodule (P = 0.012), Striga attachment (P < 0.0001) and emergence (P = 0.005), and cowpea shoot growth (P = 0.016). Cowpea nodulated poorly across host lines, Striga counts were the lowest for resistant varieties with no emerged plants. Rhizobial inoculants depressed Striga counts with consistent differences found across cowpea genotypes. Inoculation with IRJ2180A performed the best against Striga attachment in resistant genotypes, and its emergence in susceptible genotypes. In the field trial, nodule numbers were lowest in cowpea without inputs (P < 0.0001). The G x N interaction was significant in emerged Striga plants (P < 0.0001). Resistant genotypes were free of emerged Striga while for susceptible ones, Striga emergence was the highest without any input addition. Significant G x N interaction was observed in cowpea grain yield (P < 0.0001). Yield response to inoculation was most obvious for resistant genotypes inoculated with the strain IRJ2180A (P = 0.0043). The integrated use of Striga-resistant cowpea lines and elite bradyrhizobium inoculant under moderate application of P-based fertilizer could be a promising approach for mitigating Striga infestation and increasing productivity.

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An Empirically Derived Conceptual Framework to Assess Dis-Adoption of Conservation Agriculture: Multiple Drivers and Institutional Deficiencies

Journal of Sustainable Development ◽

10.5539/jsd.v12n5p48 ◽

2019 ◽

Vol 12 (5) ◽

pp. 48

Author(s):

Edna L. Chinseu ◽

Lindsay C. Stringer ◽

Andrew J. Dougill

Keyword(s):

Decision Making ◽

Smallholder Farmers ◽

Conservation Agriculture ◽

Institutional Arrangements ◽

Cultural Dimensions ◽

Sub Saharan Africa ◽

National Policies ◽

Sub Saharan ◽

Agricultural Innovations

Efforts of national governments and international agencies aimed at alleviating hunger and poverty are often undermined by lack of long-term adoption of agricultural innovations. Studies commonly explain farmers’ adoption decisions using household general determinants, yet decision-making, particularly for under-resourced smallholder farmers in sub-Saharan Africa, is a complex process. Using the case of conservation agriculture [CA], this article analyses dis-adoption of agricultural technologies by examining multiple domains of Malawi’s CA innovation system and how these influence farmer decision-making. It analyses institutional arrangements of CA promoters, national policies and farmers’ experiences. From this, we empirically derive a multifaceted dis-adoption drivers’ framework to explain CA dis-adoption in smallholder farming systems. Our findings reveal that adverse features in national policies, institutional arrangements, technological attributes and social cultural dimensions all lead to unfavourable experiences of CA for smallholder farmers, which can culminate in dis-adoption. The CA dis-adoption drivers’ framework we develop in this study provides a useful troubleshooting tool. It can be used to guide improvements in the design and implementation of project-based interventions seeking long-term adoption of agricultural innovations across sub-Saharan Africa.

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