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Biofortification of maize with provitamin A carotenoids is a new approach to the alleviation of vitamin A deficiencies in Africa. Unfortunately these varieties are yellow or orange, while consumers generally prefer white. Consumer willingness to pay for yellow and fortified maize was compared in experimental auctions in three regions in Kenya. The premium that consumers are willing pay for fortified maize (24%) was higher than the discount they require to buy yellow maize (11%), and in one zone consumers prefer yellow. Yellow color is, therefore, not an impossible obstacle for biofortified maize, although it would clearly be easier to introduce this maize first in regions where yellow maize is currently grown.  相似文献   
75.
Conservation Agriculture (CA) is advocated as an agricultural innovation that will improve smallholder famer resilience to future climate change. Under the conditions presented by the El Niño event of 2015/16, the implementation of CA was examined in southern Malawi at household, district and national institutional levels. Agricultural system constraints experienced by farming households are identified, and in response the technologies, structures and agency associated with CA are evaluated. The most significant constraints were linked to household health, with associated labour and monetary impacts, in addition to the availability of external inputs of fertiliser and improved seed varieties. Our findings show that such constraints are not adequately addressed through current agricultural system support structures, with the institutions surrounding CA (in both Government extension services and NGO agricultural projects) focusing attention predominantly at field level practice, rather than on broader system constraints such as education and health support systems. Limited capacity within local institutions undermines long term efforts to implement new technologies such as CA. It is vitally important that the flexibility of farmers to adapt new technologies in a locally-appropriate manner is not closed down through national and institutional aims to build consensus around narrow technical definitions of a climate-smart technology such as CA. To enable farmers to fully utilise CA programmes, interventions must take a more holistic, cross-sectoral approach, understanding and adapting to address locally experienced constraints. Building capacity within households to adopt new agricultural practices is critical, and integrating healthcare support into agricultural policy is a vital step towards increasing smallholder resilience to future climate change.  相似文献   
76.
非互惠的优惠贸易待遇是世界贸易组织和国际社会支持发展中国家尤其是最不发达国家发展的重要工具。为了评估该政策的效果,本文以中美对非洲实施的零关税待遇为例,采用2001—2017年HS8位贸易数据从整体、行业和区域层面评估了两种政策对受惠国出口多样化产生的影响。结果显示,美国零关税待遇分为AGOA-GSP和AGOA-服装两个条款,中国零关税待遇(FOCAC)在遵循WTO规则、受惠商品范围、受惠国家标准、原产地标准及政策有效期方面均优于AGOA-GSP,但在原产地标准灵活度和政策优惠力度方面低于AGOA-服装。这些特征导致三类政策对受惠国出口多样化的影响产生显著的差异。整体上,FOCAC和AGOA-服装对受惠国出口多样化均产生了显著的积极影响,而AGOA-GSP的影响不显著;行业层面,FOCAC对受惠国制造业、矿业和农业的出口多样化均产生了显著的促进作用,而AGOA的两个条款对受惠国三个细分行业出口多样化的影响均不显著;区域层面,三类政策对受惠国出口多样化的影响仅在部分区域发挥效果。  相似文献   
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Most studies of input subsidy programmes confine their analyses to measuring programme effects over a one‐year period. This article estimates the potential longer‐run or enduring effects of fertiliser subsidy programmes on smallholder farm households' demand for commercial fertiliser and maize production over time. We use four waves of panel data on 462 farm households in Malawi for whom fertiliser use can be tracked for eight consecutive seasons between 2003/2004 and 2010/2011. Panel estimation methods are used to control for potential endogeneity of subsidised fertiliser acquisition. Results indicate that farmers acquiring subsidised fertiliser in three consecutive prior years are found to purchase slightly more commercial fertiliser in the next year. This suggests a small amount of crowding in of commercial fertiliser from the receipt of subsidised fertiliser in prior years. In addition, acquiring subsidised fertiliser in a given year has a modest positive impact on increasing maize output in that same year. However, acquiring subsidised fertiliser in multiple prior years generates no statistically significant effect on maize output in the current year. These findings indicate that potential enduring effects of the Malawi fertiliser subsidy programme on maize production are limited. Additional interventions that increase soil fertility can make using inorganic fertiliser more profitable and sustainable for smallholders in sub‐Saharan Africa and thereby increase the cost‐effectiveness of input subsidy programmes.  相似文献   
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An international multi-disciplinary team of scientists, led by the International Livestock Research Institute (ILRI), tackled the problem of bovine trypanosomosis and the development of drug resistance in West Africa, inter alia, by the promotion of rational drug use (RDU) principles. These principles had been brought to farmers by practical training and by the provision of information leaflets. This study aimed to evaluate the impact of RDU training at smallholder level with respect to advances in farmers' knowledge and farm productivity before research outputs could be scaled up. Therefore, 508 cattle farmers attended a disease-specific knowledge test and provided information about farm production. Results show that farmers who participated in the training are more likely to identify signs and causes of the disease and to correctly administer drugs. Allocating scores to each question in the knowledge tests and scrutinizing the differences between trained and untrained farmers by matching procedures shows that participating farmers reach higher scores in all knowledge categories. Moreover, the acquisition of additional knowledge and the application of improved control strategies significantly increase farm performance. Additionally, an allocative effect was identified since trypanocide expenditures were saved by less expensive inputs.  相似文献   
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The case for promoting export‐oriented cash crops in Africa has generally been based on their direct potential contribution to agricultural productivity and small farmer incomes. A relatively neglected avenue of research concerns the synergistic effects that cash cropping can have on other household activities, including food production. The conventional view that cash crops compete with food crops for land and labour neglects the potential for cash crop schemes to make available inputs on credit, management training, and other resources that can contribute to food crop productivity, which might otherwise not be accessible to farmers if they did not participate in cash crop programs. This article builds on previous research by hypothesising key pathways by which cash crops may affect food crop activities and empirically measuring these effects using the case of cotton in Gokwe North District in Zimbabwe. Analysis is based on instrumental variable analysis of survey data on 430 rural households in 1996. Results indicate that—after controlling for household assets, education and locational differences—households engaging intensively in cotton production obtain higher grain yields than non‐cotton and marginal cotton producers. We also find evidence of regional spill‐over effects whereby commercialisation schemes induce second round investments in a particular area that provide benefits to all farmers in that region, regardless of whether they engage in that commercialisation scheme. The study suggests that the potential spill‐over benefits for food crops through participation in cash crop programs are important to consider in the development of strategies designed to intensify African food crop production.  相似文献   
80.
In this paper, we re-interpret three cases of research previously carried out in Mali, Niger and South Africa in light of the recent debate about formalisation of land rights that has emerged since the publication of Hernando de Soto's ‘Mystery of Capital’. The Malian case shows that lack of broad access to formalisation processes in high-pressure areas may play into the hands of those with power, information, and resources. The case also demonstrates that timing of formalisation efforts in urban areas characterised by rapid expansion is crucial in terms of distributive outcomes. The Nigerien case demonstrates how impending formalisation led to a scramble for land and increased conflicts in a context of institutional competition and limited administrative capacity. The South African case shows that the very process of surveying and registering rights may also change the rights themselves. Formalisation procedures may also amplify the tension between individual and communal rights, and boost privatisation.  相似文献   
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