Crop landraces have unique local agroecological and societal functions and offer important genetic resources for plant breeding. Recognition of the value of landrace diversity and concern about its erosion on farms have led to sustained efforts to establish ex situ collections worldwide. The degree to which these efforts have succeeded in conserving landraces has not been comprehensively assessed. Here we modelled the potential distributions of eco-geographically distinguishable groups of landraces of 25 cereal, pulse and starchy root/tuber/fruit crops within their geographic regions of diversity. We then analysed the extent to which these landrace groups are represented in genebank collections, using geographic and ecological coverage metrics as a proxy for genetic diversity. We find that ex situ conservation of landrace groups is currently moderately comprehensive on average, with substantial variation among crops; a mean of 63% ± 12.6% of distributions is currently represented in genebanks. Breadfruit, bananas and plantains, lentils, common beans, chickpeas, barley and bread wheat landrace groups are among the most fully represented, whereas the largest conservation gaps persist for pearl millet, yams, finger millet, groundnut, potatoes and peas. Geographic regions prioritized for further collection of landrace groups for ex situ conservation include South Asia, the Mediterranean and West Asia, Mesoamerica, sub-Saharan Africa, the Andean mountains of South America and Central to East Asia. With further progress to fill these gaps, a high degree of representation of landrace group diversity in genebanks is feasible globally, thus fulfilling international targets for their ex situ conservation.
Tag: Agroecology
Global analysis of yield benefits and risks from integrating trees with rice and implications for agroforestry research in Africa
While agroforestry is a well-established approach for agroecological intensification, rice is less often integrated with trees than other annual staple crops. The benefits and risks from rice agroforestry practices have not been systematically explored. Considering the need for strategies that may address low fertility and high degradation of arable soils and contribute to smallholder farm productivity, livelihoods and climate resilience, such exploration would both be timely and relevant. This study, therefore, reviews the published literature on integrating trees in rice production worldwide and provides perspectives for future research, with special attention to Africa, where the potential for sustainable productivity enhancement is deemed highest. Worldwide, six improved rice agroforestry practices are distinguished: hedgerow alley-cropping, short-term (0.5–4 years) improved fallows, pre-rice green manuring, biomass transfer, systematically arranged rice – tree intercropping and irregularly dispersed trees in fields. The rice agroforestry practices in the 87 publications reviewed were associated with 204 woody perennial species world-wide. Rice agroforestry practices provide a range of products and services to farmers but rice yield is the only quantitative performance indicator reported widely enough to enable meta-analysis. Frequently reported comparative or additional effects of fertilizer application, made it possible to include this aspect in the analyses. Across all types of agroforestry practices enumerated, the average effect of adding trees compared to a no-fertilizer and no-tree control is + 38%. The most beneficial practices in terms of enhancing rice yield were biomass transfer, pre-rice green manuring (100% of data points showing positive responses for both practices) and hedgerow alley-cropping (21% positive cases overall but 64% where fertilizer was not applied). Yield reductions occurred with fertilized intercropping compared to a fertilized mono-crop (in 95% of cases) and with the unfertilized short fallow practice (50% of data points showed yield reduction due to competition in the relay intercropping stage). Tree species that combined rice yield enhancements (alongside other products and services) with wide environmental adaptability across the African continent, include Sesbania rostrata, Aeschynomene afraspera, Acacia auriculiformis, Gliricidia sepium and Gmelia arborea. Yield benefits and risks from integrating trees with smallholder rice cropping depend on the type of agroforestry practice used and how each practice interacts with fertilizer application. Further research is needed to investigate the impact of different ways of integrating trees with rice cropping on wider environmental, social and economic sustainability aspects, that are driving increasing interest in rice agroforestry.
Exploring barriers to agroforestry adoption by cocoa farmers in south-western Côte d’Ivoire
Agroforestry is part of the package of good agricultural practices (GAPs) referred to as a reference to basic environmental and operational conditions necessary for the safe, healthy, and sustainable production of cocoa. Furthermore, cocoa agroforestry is one of the most effective nature-based solutions to address global change including land degradation, nutrient depletion, climate change, biodiversity loss, food and nutrition insecurity, and rural poverty and current cocoa supply chain issues. This study was carried out in South-Western Côte d’Ivoire through a household survey to assess the willingness of cocoa farmers to adopt cocoa agroforestry, a key step towards achieving sustainability in the cocoa supply chain markedly threatened by all types of biophysical and socio-economic challenges. In total, 910 cocoa households were randomly selected and individually interviewed using a structured questionnaire. Findings revealed that from the overwhelming proportion of farmers practicing full-sun cocoa farming with little or no companion trees associated, 50.2 to 82.1% were willing to plant and to keep fewer than 20 trees per ha in their farms for more than 20 years after planting. The most preferred trees provide a range of ecosystem services, including timber and food production, as well as shade regulation. More than half of the interviewed households considered keeping in their trees in their plantations for more than 20 years subject to the existence of a formal contract to protect their rights and tree ownership. This opinion is significantly affected by age, gender, access to seedlings of companion trees and financial resources. A bold step forward towards transitioning to cocoa agroforestry and thereby agroecological intensification lies in (i) solving the issue of land tenure and tree ownership by raising awareness about the new forest code and, particularly, the understanding of cocoa agroforestry, (ii) highlighting the added value of trees in cocoa lands, and (iii) facilitating access to improved cocoa companion tree materials and incentives. Trends emerged from this six-year-old study about potential obstacles likely to impede the adoption of agroforestry by cocoa farmers meet the conclusions of several studies recently rolled out in the same region for a sustainable cocoa sector, thereby confirming that not only the relevance of this work but also its contribution to paving the way for the promotion of agroecological transition in cocoa farming. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
Identifying and overcoming constraints within food systems to achieve agroecological transitions at scale – reconnecting producers and consumers
This chapter addresses the issue of identifying and surmounting constraints within agricultural, food and land systems to achieve agroecological transitions at scale.
Profitability of Gliricidia-Maize System in Selected Dryland Areas of Dodoma Region, Tanzania
Declining soil fertility and climatic extremes are among major problems for agricultural production in most dryland agro-ecologies of sub-Saharan Africa. In response, the agroforestry technology intercropping of Gliricidia (Gliricidia sepium (Jacq.)) and Maize (Zea mays L.) was developed to complement conventional soil fertility management technologies. However, diversified information on the profitability of Gliricidia-Maize intercropping system in dryland areas is scanty. Using data from the Gliricidia and maize models of the Next Generation version of the Agriculture Production Systems sIMulator (APSIM), this study estimates the profitability of the Gliricidia-Maize system relative to an unfertilized sole maize system. Results show significant heterogeneity in profitability indicators both in absolute and relative economic terms. Aggregated over a 20-year cycle, Gliricidia-Maize intercropping exhibited a higher Net Present Value (NPV = Tsh 19,238,798.43) and Benefit Cost Ratio (BCR = 4.27) than the unfertilized sole maize system. The NPV and BCR of the latter were Tsh 10,934,669.90 and 3.59, respectively. Moreover, the returns to labour per person day in the Gliricidia-Maize system was 1.5 times those of the unfertilized sole maize system. Sensitivity analysis revealed that the profitability of the Gliricidia-Maize system is more negatively affected by the decrease in output prices than the increase in input prices. A 30% decrease in the former leads to a decrease in NPV and BCR by 38% and 30%, respectively. Despite the higher initial costs of the agroforestry establishment, the 30% increase in input prices affects more disproportionally unfertilized sole maize than the Gliricidia-Maize system in absolute economic terms, i.e., 11.1% versus 8.8% decrease in NPV. In relative economic terms, an equal magnitude of change in input prices exerts the same effect on the unfertilized sole maize and the Gliricidia-maize systems. This result implies that the monetary benefits accrued after the first year of agroforestry establishment offset the initial investment costs. The Gliricidia-Maize intercropping technology therefore is profitable with time, and it can contribute to increased household income and food security. Helping farmers to overcome initial investment costs and manage agroforestry technologies well to generate additional benefits is critical for the successful scaling of the Gliricidia-Maize intercropping technology in dryland areas of Dodoma, Tanzania.
Transhumance, Tree Growing and Ecosystem Resilience
For centuries, communities in the Sahel have practiced transhumance as a coping strategy for feed and water shortages for livestock. This practice, however, is creating social, ecological and resource stress, as it is seasonally increasing the livestock footprint in landscapes already struggling with resource scarcity. It has also become a major challenge for on-farm tree growing and agricultural restoration. The large numbers of transient livestock is becoming a major concern for community forest restoration, as the animals feed on and trample planted young seedlings and saplings, hence slowing restoration. The problem encompasses both cross-border and domestic transhumance. Cross-border transhumant communities cut down trees, often resulting in conflict with local communities, who are responsible for the forest and community-managed parks.
Ecosystem-based adaptation in agriculture: How agroecology can contribute to tackling climate change
Food Sovereignty and Rights-Based Approaches Strengthen Food Security and Nutrition Across the Globe: A Systematic Review
This systematic review assembles evidence for rights-based approaches–the right to food and food sovereignty–for achieving food security and adequate nutrition (FSN). We evaluated peer-reviewed and gray literature produced between 1992 and 2018 that documents empirical relationships between the right to food or food sovereignty and FSN. We classified studies by literature type, study region, policy approach (food sovereignty or right to food) and impact (positive, negative, neutral, and reverse-positive) on FSN. To operationalize the concepts of food sovereignty and the right to food and connect them to the tangible interventions and practices observed in each reviewed study, we also classified studies according to 11 action types theorized to have an impact on FSN; these included “Addressing inequities in land access and confronting the process of land concentration” and “Promoting gender equity,” among others. We found strong evidence from across the globe indicating that food sovereignty and the right to food positively influence FSN outcomes. A small number of documented cases suggest that narrow rights-based policies or interventions are insufficient to overcome larger structural barriers to realizing FSN, such as inequitable land policy or discrimination based on race, gender or class. © Copyright © 2021 Sampson, Cely-Santos, Gemmill-Herren, Babin, Bernhart, Bezner Kerr, Blesh, Bowness, Feldman, Gonçalves, James, Kerssen, Klassen, Wezel and Wittman.
Introduction to the special issue “scaling up of agroforestry innovations: enhancing food, nutrition and income security”
It is more and more acknowledged that agroecological innovations, such as agroforestry practices, should be co-created through a combination of research and traditional knowledge, be context adaptable, and meet the needs of producers and consumers. The word “innovation” recognises that agroforestry practices do exist everywhere in the world. However, to be able to effectively respond to global challenges and changes (demography and social changes, climate, local to international markets), speaking about “innovations” implies that these practices could be improved or transformed or reintroduced everywhere they had disappeared or are in decline. This reality is still current despite the significant number of research and innovation programmes, the volume of mobilized funds and the number of participating organizations. Increasing adoption of agroforestry practices also requires long term planning and coordination because trees’ life cycles are often longer than human life. This special issue includes papers on some agroforestry innovations that merit consideration for scaling up, on successful experiences that answer priorities expressed by stakeholders while taking into account their constraints, and on systemic approaches and frameworks to the development of more comprehensive perspectives on scaling up.
Climate change impacts and adaptation for dryland farming systems in Zimbabwe: a stakeholder-driven integrated multi-model assessment
Decision makers need accurate information to address climate variability and change and accelerate transformation to sustainability. A stakeholder-driven, science-based multi-model approach has been developed and used by the Agricultural Model Intercomparison and Improvement Project (AgMIP) to generate actionable information for adaptation planning processes. For a range of mid-century climate projections—likely to be hotter, drier, and more variable—contrasting future socio-economic scenarios (Representative Agricultural Pathways, RAPs) were co-developed with stakeholders to portray a sustainable development scenario and a rapid economic growth pathway. The unique characteristic of this application is the integration of a multi-modeling approach with stakeholder engagement to co-develop scenarios and adaptation strategies. Distribution of outcomes were simulated with climate, crop, livestock, and economic impact assessment models for smallholder crop livestock farmers in a typical dryland agro-ecological zone in Zimbabwe, characterized by low and erratic rainfall and nutrient depleted soils. Results showed that in Nkayi District, Western Zimbabwe, climate change would threaten most of the farms, and, in particular, those with large cattle herds due to feed shortages. Adaptation strategies that showed the most promise included diversification using legume production, soil fertility improvement, and investment in conducive market environments. The switch to more legumes in the farming systems reduced the vulnerability of the very poor as well as the more resourced farmers. Overall, the sustainable development scenario consistently addressed institutional failures and motivated productivity-enhancing, environmentally sound technologies and inclusive development approaches. This yielded more favorable outcomes than investment in quick economic wins from commercializing agriculture.