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This work characterized two local and seven improved Cassava Mosaic Disease [CMD]-tolerant cassava varieties for their biochemical composition and viscoelastic (pasting) properties. The biochemical composition and starch pasting properties were evaluated respectively using standard analytical methods and Brabender Viscoamylograph. Cluster dendogram and principal component analyses compared similarities in the nine cassava varieties, thus predicting their varied food and industrial end uses. The different cassava varieties had starch, total sugars and reducing sugars content ranging from 53-69%, 6.5-9.2% and 0.9-2.5%, respectively. The starch content of the cassava varieties on dry weight basis (DW) varied from 54.0% to 69.0% with Nalumino having the lowest and Mweru having the highest respectively. Tanganyika, Mweulu, and Banguerlu also recorded relatively higher starch content of 62.7%, 63.6% and 63.6% respectively. Mweru, Tangayoka, Mweulu, and Bangweulu had fairly high starch content (>60%) and thus could be used for many commercial products such as starches, alcohols and glucose. The viscoelastic properties of the different varieties had pasting temperature (63.5–67.6oC), peak viscosity (402–595 BU), viscosity at 95oC (394–592 BU), viscosity at 50oC (126–254), breakdown viscosity (236–352 BU) and setback (-100–4 BU). Tanganyika recorded the highest pasting temperature (67.6oC), peak viscosity (595 BU), viscosity at 95oC (592 BU) and viscosity at 95oC-hold (317 BU). Bangweulu, Mweulu, Mweru, Manyokola, Nalumino, Kampolombo and Chila A were clustered differently from Chila B and Tanganyika on the basis of their biochemical qualities and pasting properties. These characterizations showed that Tanganyika would be suitable for products requiring high elasticity and gel strength, easier to cook and also more stable during cooking/preparation such as fufu (pounded cassava) and banku or Nshima. Chila A would also be suitable for use as fillers and binders in the baking, confectionery industries as substitutes of wheat flour. The low viscosities of Chila B make it suitable for household food uses such as snacks where the roots are boiled, roasted or toasted and consumed.

Macrotermes natalensis is a widely consumed edible termite species that inhabits termitaria of different soil colours in southern Africa. However, there is paucity of data regarding the relationship between termitaria soil properties, nutritional composition and safety for edible soldier termites. We hypothesised that soil properties viz. metal composition, and colour are positively correlated to mineral composition, bioactive compounds and level of contamination by heavy metals in soldier termites. Replicated insects samples were collected from termitaria of different soil colour types from Bikita district, Zimbabwe. Soil and insect mineral composition were determined using standard methods. Antioxidant properties of methanol insect extracts were estimated using the DPPH test. A cluster analysis was performed to relate soil colour to soil and insect minerals compositions and DPPH. Soil Zn and Cu significantly varied (P 50%) was independent of soil colour, soil and insect mineral composition. There is a possible risk of Pb poisoning associated with consumption of soldier Macrotermes natalensis irrespective of termitaria soil colour; however, the risk is more pronounced in insects gathered from yellowish-brown soils.

Cassava was domesticated in the Amazon Basin, where Native Americans selected many bitter varieties, and devised methods for detoxifying them. Cassava reached Africa in the sixteenth century, where rural people soon learned to remove the cyanogenic toxins, e.g., by drying and fermenting the roots. Processing cassava to remove the cyanogenic toxins including the cyanide formed during the processing is time consuming. The work is often done by women, while women and men often prefer bitter cassava varieties for social reasons and superior taste and color. In spite of deep, local knowledge of safe processing, traditional foods made with contaminated water may contain bacterial and fungal pathogens. Improper storage may encourage mycotoxins, such as aflatoxin. Recent advances in industrial processing are developing foods that are free of toxins and microbial contamination. Processing and selling cassava leaves is an emerging but fast-growing sector. Cassava leaves also contain cyanogenic toxins normally in higher concentrations than the cassava roots. In the future, more attention must be paid to the safe processing of cassava leaves and roots, especially as food processing becomes increasingly industrialized worldwide.

In nearly all parts of the world, an important part of people’s livelihood is derived from natural resources. Gender is considered one of the most important determinants of access and control over forests. It is thought that women and men within households and communities have different opportunities and different roles and responsibilities in relation to forest use. It is probable that when women have equal access to forests, better food security outcomes can be achieved for individuals and households that are dependent on forests for their livelihoods. A systematic evidence map of the evidence base linking gender with access to forests and use of forest resources for food security was undertaken. Ten bibliographic databases and 22 websites of international development and conservation organisations were searched using keywords suggested by stakeholders. Other articles were found by emailing authors and organisations to send potentially relevant publications. 19,500 articles were retrieved from bibliographic databases and 1281 from other sources. After iterative screening, 77 studies were included: 41 focussed on Africa, 22 on Asia, 12 on Latin America, 2 were global. Most indicators of food security measure access to food, measured by total consumption, expenditure, or income. Studies showed strong gender specialisation: commercial access and utilisation of forests and forest products dominated by men, whereas access for subsistence and household consumption is almost exclusively the task of women. Despite the large number of studies reviewed, limitations of the evidence base, including methodological heterogeneity, a dominance of case studies as the study design, and unequal geographical representation in study locations, make it difficult to generalise about the overall importance of gender and its effect on access to and use of forests for food security in developing countries. The critical gaps in the evidence base include geographical representation in primary research and a greater breadth of study designs to assess gender implications of access to forest resources globally.

It is not just the world but our ways of producing knowledge that are in crisis. The Covid-19 pandemic has exposed our interconnected vulnerabilities in ways never seen before while underscoring the need for emancipation in particular from the hegemonic knowledge politics that underpin “business-as-usual” academic research that have both contributed to and failed to address the systemic challenges laid bare by the pandemic. Political ecologists tasked with knowledge generation on vulnerabilities and their underlying power processes are particularly well placed to envision such emancipatory processes. While pausing physically due to travel restrictions, as researchers in political ecology and rural development at the same university department, we want to make a stop to radically rethink our intellectual engagements. In this article, we aim to uncover “sanitized” aspects of research encounters, and theorize on the basis of anecdotes, feelings and informal discussions—“data” that is often left behind in fieldwork notes and personal diaries of researchers—, the ways in which our own research practices hamper or can be conducive to emancipation in times of multiple interconnected health, political, social, and environmental crises. We do so through affective autoethnography and resonances on our research encounters during the pandemic: with people living in Swedish Sapmi, with African students in our own “Global North” university department and with research partners in Nepal. We use a threefold focus on interconnectedness, uncertainty and challenging hegemonic knowledge politics as our analytical framework. We argue that acknowledging the roles of emotions and affect can 1) help embrace interconnectedness in research encounters; 2) enable us to work with uncertainty rather than “hard facts” in knowledge production processes; and 3) contribute to challenging hegemonic knowledge production. Opening up for emotions in research helps us to embrace the relational character of vulnerability as a pathway to democratizing power relations and to move away from its oppressive and colonial modes still present in universities and research centers. Our aim is to contribute to envisioning post-Covid-19 political ecology and rural development research that is critically reflexive and that contributes to the emergence of a new ethics of producing knowledge. Historically, pandemics have forced humans to break with the past and imagine their world anew. This one is no different. It is a portal, a gateway between one world and the next. We can choose to walk through it, dragging the carcasses of our prejudice and hatred, our avarice, our data banks and dead ideas, our dead rivers and smoky skies behind us. Or we can walk through lightly, with little luggage, ready to imagine another world. And ready to fight for it. (Roy, 2020)

Entrepreneurial activities in rural context play a significant role in creating employment, food security, and general rural livelihood. However, gendered constraints to the disadvantage of women pose a huge constraint. Digitalization has significant possibilities to minimize these constraints. However, less has been documented on how digitalization addresses the gender constraints to enhance women’s engagement in rural entrepreneurship.

Like the rest of the world, African countries are reeling from the health, economic and social effects of COVID-19. The continent’s governments have responded by imposing rigorous lockdowns to limit the spread of the virus. The various lockdown measures are undermining food security, because stay at home orders have among others, threatened food production for a continent that relies heavily on agriculture as the bedrock of the economy. This article draws on quantitative data collected by the GeoPoll, and, from these data, assesses the effect of concern about the local spread and economic impact of COVID-19 on food worries. Qualitative data comprising 12 countries south of the Sahara reveal that lockdowns have created anxiety over food security as a health, economic and human rights/well-being issue. By applying a probit model, we find that concern about the local spread of COVID-19 and economic impact of the virus increases the probability of food worries. Governments have responded with various efforts to support the neediest. By evaluating the various policies rolled out we advocate for a feminist economics approach that necessitates greater use of data analytics to predict the likely impacts of intended regulatory relief responses during the recovery process and post-COVID-19.

This paper presents new data on urban households’ agriculture, food environments and non-communicable disease (obesity, diabetes, hypertension) in two intermediate-sized Ugandan cities (Mbale and M ...

This chapter discusses the food safety and quality considerations for cassava (Manihot esculenta), a major staple across the developing world and one that is attracting increasing interest from developed country markets and consumers, as well as policy makers. It includes discussions on the agronomy and agricultural production, the types of cassava products in different continents, how they are traditionally and commercially made, nutritional considerations and how the products are used. Production of different cassava products and the attendant considerations for products for domestic consumption (e.g. gari), the export products from cassava (bammies, flour, others) and cassava toxicology, including the role of the cyanogenic glycosides and aflatoxin, and food safety. Discussion involve mitigating natural toxicants, quality considerations, implementation FSQS, and considerations for future growth and utilization of this important staple.

This paper examines the linkage between resource scarcity and conflict during the 2012 Lake Chilwa water level recession. Ecosystem degradation and resource scarcity negatively affect many poor people dependent on aquatic systems such as river floodplains and wetlands. The need to identify and implement innovative measures to manage the scarce resources in these systems has sometimes resulted in conflicts among the various resource users such as fishers, farmers and political groups. However, the direct causal links between resource scarcity and conflict are contested and the evidence base is weak. Using empirical evidence from focus group discussions and in-depth interviews conducted at Chisi Island of Lake Chilwa as a case study, we define the governance groups (vertical and horizontal) and the direct causal links between environmental scarcity and conflict during the 2012 lake recession. We argue that the actual risk of increasing conflicts caused by resource scarcity will depend on the level of vulnerability of populations, ecosystems, economies and institutions in the context of authority, legitimacy and capacities to effectively manage resource scarcity.

Faced with limited resources, scientists from around the world enter into collaborations to join their resources to conduct research. Like everywhere else, international co-publishing in southern African countries is increasingly on the rise. The aim of this study was to document and analyse the level of scientific productivity, collaboration patterns, scientists' experiences and attitudes towards South---South and South---North collaboration. We performed 105 interviews with scientists based at five southern African Universities, namely; University of Malawi--Chancellor College, National University of Science and Technology, the University of Botswana, the University of Zambia, and the University of Zimbabwe. We also traced 192 scientists from the various departments at these universities that had jointly published 623 scientific papers in the field of basic sciences in the period 1995---2014 in Web of Science journals. Our results show that in the majority of the cases funding from the North contributed substantially to increased scientific productivity, and international co-authorship. The results also show that collaboration with southern scientists is equally valued as that with northern scientists, but for different reasons. We conclude that supporting international and national collaboration which includes increased scientific mobility, strong scientific groups and networks, are key factors for capacity building of research in southern African Universities.

Cassava (Manihot esculenta Crantz) varieties are ethnobotanically classified by farmers into two distinct classes—“sweet” or “bitter”—based on their taste, most often reflecting the inherent cyanogenic glucoside potential and intended end use. Varietal preference based on general utilization as well as more targeted end use for preferred local and improved varieties is poorly understood and not well documented. The objectives of this study were to investigate prevailing varietal preferences based on utilization and the biochemical composition of local and recently improved cassava varieties. Interviews were conducted with farmers to document the existing varieties, their origin and taste classification, and processing in relation to end use. Biochemical composition was determined for flour samples with particular emphasis on color and perceived dryness. Of the nine varieties identified, four were classified as local, while the rest were classified as improved varieties. Two varieties were classified as bitter, and the rest were classified as sweet based on end use. The classification dichotomy based on taste is an important factor in determining potential toxicity. Labile varieties that are easily affected by microenvironmental factors were classified as bitter. Reasons for preference and utilization focus as much on the leaves for use as vegetables as on the roots. The taste classification of the roots determines how and whether they are to be processed. The varieties “Mweulu” and “Tanganyika” were perceived by farmers as having excellent characteristics for making the staple dish “nshima,” reflected by their high carbohydrate contents. The variety “Bangweulu” was identified as having “bigger and starchier” roots in interviews, and the biochemical assay verified these observations. The flour sample analysis revealed crude protein content ranged from 4.86% to 7.09%. Cluster and principal component analyses showed four groupings, with the single Malawian variety exhibiting the greatest differences from the Zambian clones, while the improved varieties bred from a single mother line displayed the closest similarities. The high energy and carbohydrate values of the nine varieties provide a good basis for acceptance; however, factors such as shelf life, storage, and other postharvest qualities such as susceptibility to weevil attacks also play a determining role in the acceptance of improved cassava varieties.

This paper provides an in-depth understanding of social dynamics in the form of kinship ties in matrilineal societies. It unpacks gender roles and relationships at the community level to understand how social structures, created by the pattern of relations, enhance or hinder coping initiatives during lake recessions in the Lake Chilwa socio-ecological system. Using qualitative and quantitative methods including in-depth interviews, Focus Group Discussions (FGD) and household questionnaires, this paper provides insights into how people in the Lake Chilwa social-ecological system prepare for and cope with Lake Chilwa water recessions by capitalising on their social networks. The findings have shown that during lake recessions poor households in the Lake Chilwa socio-ecological system are cushioned by fellow households through lineage networks. There is strong tradition secured through kinship ties where the generic term 'mwambo wathu' (our tradition) embraces a group of formative norms enforced via a series of rules and rituals. Based in a matrilineal system, women have strong rights over land allocation and use in which the female sorority group 'mbumba' is very stable. There is a great deal of reciprocity and food redistribution among the households. This self-organization provides deeper meaning about how people assimilate the dynamics affecting their social and natural environments. Specifically the findings provide evidence on how households, communities and their livelihoods in Africa are reconstructed as natural resources fluctuate.

PurposeCassava production surged noticeably in Southeastern Africa beginning in the 1990s. The purpose of this paper is to examine the commercial responses and food security consequences of cassava production growth in the region.Design/methodology/approachThe paper incorporates a mix of quantitative analysis, based primarily on original analysis of national farm household survey data, together with key informant interviews with value chain participants in the three neighboring countries of Malawi, Mozambique and Zambia.FindingsIn the cassava production zones, cassava's high productivity translates into per kilogram carbohydrate costs 60 per cent to 70 per cent of the cost of cereals such as maize and wheat, thereby opening up a range of profitable opportunities for commercialization of cassava‐based foods, feeds and industrial products. Despite this potential, cassava commercialization in Southeastern Africa remains in its formative stages, with only 10 per cent to 30 per cent of production currently marketed. Unlike West Africa, where cassava commercialization has centered on marketing prepared cassava‐based convenience foods, the emerging cassava markets in Southeastern Africa have centered on fresh cassava, low value‐added cassava flour, and experiments in industrial processing of cassava‐based starches, biofuels and feeds. Strategic investment in a set of key public goods (breeding, training in food sciences and food safety, and research on in‐ground cassava storage) can help to shape this transition in ways that benefit both commercial interests and the food security of vulnerable households.Originality/valueThe paper compares cassava commercialization across differing agro‐climatic zones, policy environments and food staple zones.

Global climate issues and a looming energy crisis put agriculture under pressure in Sub-Saharan Africa. Climate adaptation measures must entail sustainable development benefits, and growing crops for food as well as energy may be a solution, removing people from hunger and poverty without compromising the environment. The present study investigated the feasibility of using non-food parts of cassava for energy production and the promising results revealed that at least 28% of peels and stems comprise dry matter, and 10 g feedstock yields >8.5 g sugar, which in turn produced >60% ethanol, with pH ≈ 2.85, 74–84% light transmittance and a conductivity of 368 mV, indicating a potential use of cassava feedstock for ethanol production. Thus, harnessing cassava for food as well as ethanol production is deemed feasible. Such a system would, however, require supportive policies to acquire a balance between food security and fuel.

Cassava is a tropical crop and grown for its tuberous starchy roots. In Africa it is mainly cultivated by small-scale farmers who observe, select and name their cassava varieties based on morphology, food, social and economic interest. Here we have used an interdisciplinary approach involving farmer interviews, genetic markers and morphological descriptors to study the composition of cassava varieties on small-scale farms in 11 villages located in three districts in Uganda, the genetic structure within and between these varieties and their morphology. The composition of local, newly introduced and improved varieties differed widely between villages and districts. The Ugandan farmers in our study seemed to adopt improved varieties to a greater extent when there was a nearby market, prevalence of disease epidemics and good extension service. We found considerable genetic variation both within and between cassava varieties though the variation was larger between varieties. However, most local and improved varieties showed predominating genotypes at many loci. Accessions of commonly grown varieties meeting farmers' preferences could therefore be selected and implemented in future breeding programmes involving development, dissemination and adoption. The like-named varieties in different villages were genetically similar, demonstrating farmers' ability to differentiate and maintain the same variety over large areas. However, some varieties with different names in different villages showed both genetic and morphological similarity, suggesting that farmers may rename plants when they are introduced into their fields. The large differences found in variety and genetic composition between villages and districts in Uganda may be a result of the diverse needs and growing conditions characteristic for traditional farming system. This suggests that efforts to conserve and increase the genetic diversity in farmers' fields will require policies tailored to each area.

Cassava roots contain cyanogenic glucosides. Malawian farmers classify cultivars into two groups based on the perceived danger of eating raw roots that they associate with bitterness. In the vernacular, cultivars that produce roots with bitter taste are called vyakubaba (bitter), whereas those yielding non-bitter roots are called vyakuzizra (cool). In the scientific literature they are distinguished as ‘bitter’ or ‘sweet’. Roots from ‘bitter’ cultivars are processed prior to consumption. We studied the ability of farmers to predict the cyanogenic glucoside levels of 492 roots from the 10 most commonly grown cultivars. Twenty-eight farmers predicted the taste of each of the cultivars that they grew, and scored bitterness on a five-point scale by tasting the root tip. Thereafter cyanogenic glucosides were determined on half of the root, while a taste panel scored the taste of the other half. The mean cyanogenic glucoside level in 132 roots from ‘cool’ cultivars was 29 mg HCN eq kg−1 fresh weight (CI 25–33, range 1–123) and in 360 roots from ‘bitter’ cultivars was 153 mg HCN eq kg−1 fresh weight (CI 143–163, range 22–661). Farmers' distinction of ‘cool’ and ‘bitter’ cultivars predicts glucoside levels. The tasting of the tip of the root improved the farmers' prediction of toxicity. Scoring of bitterness by a trained taste panel showed a stronger correlation with glucoside levels (r2 = 0.67). This suggests that cyanogenic glucosides confer the bitter taste, notwithstanding the probability of additional modifying intrinsic factors. Copyright © 2004 Society of Chemical Industry

Cassava roots, a major food in Africa, contain cyanogenic glucosides that may cause toxic effects. Malawian women farmers considered fields of seemingly similar cassava plants to be mixes of both ‘cool’ and ‘bitter’ cultivars. They regard roots from ‘cool’ cultivars as non-toxic. Roots of ‘bitter’ were considered to require extensive traditional processing done by women to be safe for consumption. But curiously, these women farmers preferred ‘bitter’ cultivars since toxicity confers protection against theft, which was a serious threat to the food security of their families. We studied how well these farmers comprehend the effects of genetic variations in cassava when dealing with cyanogenesis in this complex system. Using molecular markers we show that most plants farmers identified as belonging to a particular named cultivar had a genotype typical of that cultivar. Farmers' ethno-classification into ‘cool’ and ‘bitter’ cultivars corresponded to a genetic sub-division of the typical genotypes of the most common cultivars, with four-fold higher cyanogenic glucoside levels in the bitter cultivars. Examining morphology, farmers distinguished genotypes better than did the investigators when using a standard botanical key. Undoubtedly, these women farmers grasp sufficiently the genetic diversity of cassava with regard to cyanogenesis to simultaneously benefit from it and avoid its dangers. Consequently, acyanogenic cassava – the breeding of which is an announced good of some cassava genetic improvement programmes – is not a priority to these farmers. Advances in molecular genetics can help improve food supply in Africa by rapid micropropagation, marker assisted breeding and introduction of transgenic varieties, but can also help to elucidate tropical small-scale farmers' needs and skills.

In a cassava-growing area in Malawi, where roots are processed by soaking and water is available throughout the year, we interviewed 176 women farmers regarding their preferences for cassava cultivars and frequency of cassava consumption. Dietary cyanogen exposure was estimated from urinary levels of linamarin, the cyanogenic glycoside in cassava, and urinary thiocyanate, the main cyanide metabolite. Protection against unplanned harvest by family members, theft and animal spoilage were stated to be very important reasons for growing bitter cassava cultivars by 91%, 90% and 74% of the women, respectively. The mean (+/- SD) number of cultivars grown by each woman was 4.6 (+/- 2.4). The correlation between mean taste and mean danger scores for the 25 most grown cultivars was strong (r0.98). The scoring indicated that cultivars belonged to two distinct groups, eight to a group referred to as 'cool' and 17 to a group termed 'bitter'. The dumpling-like porridge (kondowole) made from cassava flour from bitter roots was eaten twice daily by 51% and at least weekly by 81%. The mean (+/- SEM) urinary linamarin was 14 (+/- 1) mumol/L and thiocyanate was 50 (+/- 4) mumol/L, less than a tenth of levels reported from populations eating insufficiently processed bitter cassava roots, and in the same range as in a non-smoking Swedish reference population. We conclude that cyanogenesis is a preferred characteristic of cassava by the studied farmers because it enhances food security. The availability of water and their knowledge about toxicity and processing enables these women farmers to provide a safe staple food from bitter cassava roots.

We conducted qualitative interviews in Nkhata‐Bay district in Malawi to elucidate why farmers preferentially grow cassava cultivars providing bitter roots. Cassava was mainly grown to produce flour for making the staple food, kondowole. Plants were identified as belonging to one of the 54 mentioned cultivars with local names. All the farmers stated that bitter taste of roots predicted toxicity and necessity for processing. Cultivars were grouped into “cool” or “bitter” based on whether the roots could be eaten fresh, or required processing before consumption as kondowole. Farmers strongly preferred cultivars grown for flour production to have bitter roots since this protected against theft, destruction by animals and deterred household members from unplanned harvest. Since processing is done by women bitterness empowers women to control the families staple crop. Bitter cultivars reportedly yielded more and roots produced an easier to mould kondowole. Bitterness and toxicity were not perceived as a problem.

1. Agro-ecological Intensification of Farming Systems in the East and Central African Highlands Bernard Vanlauwe, Guy Blomme and Piet van Asten 2. Agricultural Intensification and the Food Security Challenge in Sub-Saharan Africa Brian A. Keating, Peter S. Carberry and John dixon 3. The Agro-ecological Solution?! Food Security and Poverty Reduction in Sub-Saharan Africa, with an Emphasis on the East African Highlands Henk Breman Theme 1: Systems Components 4. CIALCA Interventions for Productivity Increase of Cropping System Components in the African Great Lakes Zone Pieter Pypers et al. 5. Exploring the Scope of Fertilizer Use in the East African Region Lydia Wairegi and Piet van Asten 6. The 4R Nutrient Stewardship in the Context of Smallholder Agriculture in Africa Shamie Zingore and Adrian Johnston 7. Mitigating the Impact of Biotic Constraints to Build Resilient Banana Systems in Central and Eastern Africa Rony Swennen et al. 8. Challenges for the Improvement of Seed Systems for Vegetatively Propagated Crops in Eastern Africa Julian Smith, Daniel Coyne and Elmar Schulte-Geldermann Theme 2: System Integration 9. CIALCA's Efforts on Integrating Farming System Components and Exploring Related Trade-offs Piet van Asten et al. 10. Towards Ecologically Intensive Smallholder Farming Systems: Design, Scales and Trade-offs Evaluation Pablo Tittonell 11. Using the 'Livestock Ladder' as a Means for Poor Crop-livestock Farmers to Exit Poverty in Sud-Kivu Province, Eastern DR Congo Brigitte L. Maass et al. 12. N2Africa: Putting Nitrogen Fixation to Work for Smallholder Farmers in Africa Ken E. Giller et al. 13. Integrating Climate Change Adaptation and Mitigation in East African Coffee Ecosystems Henk van Rikxoort et al. Theme 3: Drivers for Adoption 14. Agricultural Technology Diffusion and Adoption in Banana and Legume Based Systems of Central Africa Emily Ouma et al. 15. Supply and Demand Drivers of the Sustainable Intensification of Farming Systems through Grain Legumes in Central, Eastern and Southern Africa Joseph Rusike et al. 16. Assessing and Improving the Nutritional Diversity of Cropping Systems Roseline Remans et al. 17. Disseminating Agroforestry Innovations in Cameroon: Are Relay Organizations Effective? Ann Degrande et al. 18. Participatory Re-introduction of Vicia Faba Beans in Resource-poor Farming Systems: Adoption of a Farmer-led Initiative Erik Karltun et al. Theme 4: Communicating and Disseminating Complex Knowledge 19. Walking the Impact Pathway: CIALCA's Efforts to Mobilize Agricultural Knowledge for the African Great Lakes Region Boudy van Schagen et al. 20. Scalability and Farmer Heterogeneity: Implications for Research on Sustainable Intensification John Lynam 21. Integrated Agricultural Research for Development (IAR4D): An Approach to Enhance the Livelihoods of Smallholder Farmers in the Lake Kivu Region Robin Buruchara et al. 22. Communication Channels Used in Dissemination of Soil Fertility Management Practices in the Central Highlands of Kenya Sarah W. Kimaru-Muchai et al. 23. Targeting Farmers' Priorities for Effective Agricultural Intensification in the Humid Highlands of Eastern Africa Jeremias Mowo et al. Index

Investigations were conducted to characterize six high yielding cassava mosaic disease (CMD) resistant cassava varieties (Ampong, Broni bankye, Sika, Otuhia, Amakuma and Bankye fitaa) that have been developed by the Crop Research Institute of Ghana in collaboration with the International Institute for Tropical Agriculture for their differences and similarities in viscoelastic properties and physico-functional characteristics. The viscoelastic properties (pasting temperature, peak viscosity, final viscosity, breakdown viscosity and setback viscosity), and physico-functional characteristics (swelling power, solubility and water binding capacity) were determined using standard analytical methods. The results showed wide variations in viscoelastic properties with values ranging from 270.67-380.67 BU for peak viscosity, 37.17-260 BU for final viscosity, 199.83-282.33 BU for breakdown viscosity, 21.83-98.66 BU for setback viscosity and 2.48-10.51 min time to pasting temperature. Similarly, variations in swelling power, solubility and water binding capacity were noted with values ranging between 14.34-17.04%, 73.04-79.98% and 234.53- 276.63% respectively for all the different cassava genotypes. Statistical analysis showed significant differences (P < 0.05) amongst the studied cassava genotypes with Sika (improved variety) having exceptionally high viscoelastic characteristics. The differences noted in the viscoelastic properties and physico-functional characteristics of the six CMD resistant cassava genotypes could be used in their selection for specific food and industrial processing applications.

High yielding and cassava mosaic disease (CMD) resistant cassava varieties have been developed by the Crop Research Institute of Ghana with varying compositions and concentrations of starches and sugars. This study characterized four of these improved cassava varieties (Ampong, Broni bankye, Sika and Otuhia) together with two traditional varieties (Amakuma and Bankye fitaa) for their composition of starches and sugars using principal component and cluster analyses. The concentration of total sugars, reducing and non-reducing sugars, sucrose, starches, amylose and amylopectin were determined using standard analytical methods. Results obtained were total sugar (4.04-18.47%), non-reducing sugar (2.08-16.21%), sucrose (1.98-15.40%), starch (15.39-31.07%) and amylose (30.57-40.33%) and these were significantly different (p < 0.05) amongst the studied cassava varieties. The improved varieties (Ampong, Broni bankye, Sika and Otuhia) had high total sugar levels ranging from 7.19 to 18.47 %. With the exception of Broni bankye (improved variety) all the improved and traditional varieties were high starch and amylose containing varieties. These differences in the biochemical composition of the traditional and improved cassava varieties could be used in their selection for specific food and industrial processing applications.

The cassava belt area in Southern Africa is experiencing an unforeseen surge in cassava production, processing and consumption. Little documentation exists on the effects of this surge on processing procedures, the prevailing levels of cyanogenic glucosides of products consumed and the levels of products commercially available on the market. Risk assessments disclose that effects harmful to the developing central nervous system (CNS) may be observed at a lower exposure than previously anticipated. We interviewed farmers in Zambia and Malawi about their cultivars, processing procedures and perceptions concerning cassava and chemical food safety. Chips, mixed biscuits and flour, procured from households and markets in three regions of Zambia (Luapula-North, Western and Southern) as well as products from the Northern, Central and Southern regions of Malawi, were analyzed for total cyanogenic potential (CNp). Processed products from Luapula showed a low CNp