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1.
Cowpea covers the largest area of any grain legume in Africa and is especially important in West Africa where Nigeria and Niger alone account for over 75% of the total cowpea production in the world. Despite successes of international and national cowpea improvement research in the development and release of several improved varieties, there is limited empirical evidence of adoption and ex-post impacts of improved cowpea. Using a nationally representative survey data from a sample of 1,525 cowpea-growing households in northern Nigeria cultivating over 2,500 cowpea plots, we assess the adoption and impacts of improved cowpea varieties on cowpea yields, net returns and production costs. We apply a control function approach and propensity score matching models to estimate the causal effects of adoption of improved cowpea varieties . Our results show that 38% of the cowpea plots were planted with improved varieties, and cowpea yields, net returns and production costs increase significantly with the adoption of improved cowpea varieties. Adoption of improved cowpea varieties is associated on average with 26% yield gains, 61% increase in net returns and 14% increase in production costs. We also show that farmers who have a lower propensity to adopt improved cowpea varieties also face higher costs of production.  相似文献   

2.
ABSTRACT

Cowpea (known as black-eyed peas in America) is the most important indigenous African grain legume for both home use and as a cash crop. Because of its tolerance to drought, it is especially important for the Sahel. Genetic transformation of cowpea with Bacillus thuringiensis (Bt) genes to control pod-boring insects has many advantages, but little is known of the potential consumer response. This article analyzes and reports the results of a survey of 200 consumers in northern Nigeria concerning consumer awareness of and acceptance of biotechnology. Ninety percent of the respondents were aware of genetically modified (GM) products. Those respondents who were most concerned about the ethics of genetic transformation were likely to disapprove of such products, while those individuals who identified international radio as an information source were more likely to approve of GM technology.  相似文献   

3.
The distribution of welfare gains of genetic improvements in major US crops is estimated using a world agricultural trade model. Multi-market welfare estimates were 75% larger than estimates based on the price-exogenous 'change in revenue' method frequently used by plant breeders. Annual benefits of these genetic improvements range from US$ 400–600 million depending on the supply shift specification. Of this, 44–60% accrues to the US, 24–34% accrues to other developed countries. Developing and transitional economies capture 16–22% of the welfare gain. The global benefits of a one-time permanent increase in US yields are US$ 8.1 billion (discounted at 10%) and US$ 15.4 billion (discounted at 5%). Gains to consumers in developing and transitional economies range from US$ 6.1 billion (10% discount rate) to US$ 11.6 billion (5% discount rate).  相似文献   

4.
This paper investigates the impact of China's and Taiwan's accession to the World Trade Organization (WTO) on U.S. and world agricultural trade by means of a 12-region, 14-sector Computable General Equilibrium model for world trade and production. The simulation results show that integrating China and Taiwan into the global trading system could induce more competition on labor-intensive Products and reduce their prices. It could drive up the demand for capital and skill-intensive manufactured goods, thus further improving industrial countries' terms of trade. The expansion of labor-intensive sectors in China could also induce contraction in agricultural exports from China and increase its net agricultural imports by as much as US$9 billion annually, causing food and agricultural exports from other regions to increase. Total U.S. food and agricultural exports could increase by about US$2.4 billion annually, with the non-grain crop sectors gaining the most. The biggest winner from China's WTO accession is China itself. WTO membership could bring a net welfare gain of about US$30 billion a year for China, a substantial benefit compared with the gains for the USA (US$8.5 billion).  相似文献   

5.
European consumers and, in particular, German consumers are known to be very critical toward the introduction of genetically modified (GM) foods. It is analyzed here whether German consumers do reject second-generation GM foods, too. Whereas first-generation GM crops induced producer-related benefits, second-generation GM crops are associated with consumer-oriented benefits like an improvement of nutritional quality. The determinants of demand for second-generation GM rapeseed oil are investigated within an online survey of 1,556 German consumers. It is elaborated how two functional properties of the product matter; that is, long-chain omega-3 fatty acids and the cholesterol-lowering effect of phytosterols. It turns out that GM rapeseed oil is neglected by 74% of all respondents. Output traits, however, will increase the probability of purchases of GM rapeseed oil. This is more the case for long-chain omega-3 fatty acids than for phytosterols.  相似文献   

6.
This study evaluates the potential impacts of the Improved Maize for African Soils (IMAS) project in two countries of Africa: Kenya and South Africa. The IMAS varieties offer significant yield advantages for regions where low or no fertilizer is used. The analysis uses spatial production data and household data to account for the level of fertilizer use in different agroecological zones of the country as well as different types of maize producing households. Results suggest that IMAS will deliver a total of US$586 million in gross benefits with US$136 million and US$100 million of benefits to producers in Kenya and South Africa, respectively, and an additional US$112 million to consumers in Kenya and US$238 million to consumers in South Africa. These benefits could help more than 1 million people escape poverty in the two countries by 2025. Household level results suggest that small households in areas with relatively low levels of fertilizer use stand to gain significant benefits.  相似文献   

7.
Since their independence, many countries in sub-Saharan Africa have used input subsidies to increase agricultural productivity and improve food security. We analyse the effects of both a fertiliser and a seed subsidy on farming households' land allocation among crops and crop diversity in Burkina Faso. Although previous studies investigated either the impact of a fertiliser or a seed subsidy on targeted crops, few examined the effects of both subsidies combined. Applying a correlated random-effects model with a control function approach to nationally representative, 2-year panel data collected from farming households, we find that those with access to the fertiliser subsidy allocate more land to the crops it targets (rice, maize and cotton) than non-targeted crops. Focusing on a minor crop with key agronomic and nutritional attributes, we conclude that land allocation to cowpea as the primary crop and intercrop declined with the fertiliser subsidy. The fertiliser subsidy also negatively affects crop diversity. However, we find that the cowpea seed subsidy offsets the bias of fertiliser subsidy toward fertiliser-targeted crops and enhances diversity.  相似文献   

8.
For countries with recurrent droughts, the design of drought impact mitigation measures could benefit from analyses of determinants of yields and prices of local crops at regional and district level. This study applies dynamic spatial panel data regression models to yields and prices of four major food crops across regions of Burkina Faso and Niger, over sample periods between 1984 and 2006. Results lend support to mainly simultaneous spatial spillovers, particularly for millet and cowpea prices and sorghum yields in Niger, and maize yields in Burkina Faso. After accounting for these effects, most crop yields are found to be weakly price‐responsive, as envisaged by a supply‐side geographical diffusion hypothesis. Seasonal rainfall elasticity estimates suggest that dominant food crops have slight advantage margins in terms of relative resilience to rainfall shortages. However, this result is to be weighed against low millet yields in Niger, and marked drops in sorghum yields during officially declared droughts in Burkina Faso.  相似文献   

9.
This paper builds on the literature on the economic effects of the second‐generation, consumer‐oriented genetically modified products (GMPs). It analyses the market and welfare impacts of the introduction of these new products in markets, like the EU, that mandate the segregation and labelling of the first‐generation, producer‐oriented GMPs. Developing an empirically relevant model of heterogeneous consumers and producers, the study determines the effects of the consumer‐oriented GMPs on the markets of conventional, GM and organic products, and the welfare of consumers and agricultural producers. Analytical results indicate that the market effects of the new GMPs are case specific and depend on: (i) the consumer valuation of the quality‐enhancing attribute of the new GMP; (ii) the level of consumer aversion to GMOs; (iii) the strength of consumer preference for organic products; and (iv) the production costs and marketing margins in the different supply channels. The policy on the labelling of the first‐generation GMPs does not affect the impacts of the second‐generation GMPs on the quantities and market shares of the different products. However, it does affect their price effects and welfare implications. The introduction of consumer‐oriented GMPs under a mandatory labelling regime can result in losses for some GM consumers and all producers of the conventional product.  相似文献   

10.
This article examines the magnitude and sources of yield variation among adopters of improved cowpea varieties in northern Nigeria promoted through farmer‐to‐farmer diffusion. The results reveal important efficiency differences between the lead farmers who have contacts with breeders and the follower farmers who get technology and information from the lead farmers. Differential adoption of the package of seed, insecticide, fertilizer, and recommended cereal‐cowpea cropping pattern provides much of the explanation for yield variation among adopters. The component often missing, and hence accounting for much of the yield variation, is the crop management technology relating to the cereal‐cowpea cropping pattern. No efficiency variation is attributed to the source of technology and information, such as whether improved cowpea was obtained from breeders or lead farmers. Technology source has a rather indirect influence on efficiency through its effect on package adoption where breeders promote greater package adoption among the lead farmers than the lead farmers do among the follower farmers. Possible ways of disseminating crop management technological information through the farmer‐to‐farmer technology diffusion are recommended to better exploit the yield and profitability potentials of improved cowpea varieties in northern Nigeria.  相似文献   

11.
Although adoption rates of genetically modified crops have been staggering in some countries, there is still comparatively little evidence about biotechnology impacts under diverse agroecological and institutional conditions. These knowledge gaps lead to an overly precautious attitude among policy makers and the public. This article analyzes the effects of Roundup Ready (RR) soybeans in Argentina, the country with the second biggest transgenic area worldwide. Based on recent survey data, it is shown that the technology increases total factor productivity by 10% on average, with cost savings being somewhat more pronounced for smaller than for larger farms. The reduction in use of toxic herbicides and of tillage operations entails positive environmental repercussions. Aggregate welfare effects are computed over the 1996–2001 period with a three-region, partial equilibrium model, comprising Argentina, the United States, and the rest of the world. In 2001, RR soybeans created more than US$1.2 billion of economic surplus at the global level. The largest share went to consumers (53%), followed by seed and biotechnology firms (34%), and agricultural producers (13%). Due to comparatively weak intellectual property protection, and thus only small technology mark-ups in seed prices and widespread adoption, Argentine soybean growers receive 90% of the benefits in that country. This demonstrates that farmers in developing countries can gain considerably when they obtain access to suitable foreign innovations through technology spill-overs.  相似文献   

12.
This study explores consumer acceptance and valuation of a genetically modified (GM) staple food crop in a developing country prior to its commercialization. We focus on the hypothetical introduction of a disease‐resistant GM banana variety in Uganda, where bananas are among the most important staple crops. A choice experiment is used to investigate consumer preferences for various attributes related to the banana (such as bunch size, technology, producer benefit, and price) and examine their opinions on GM foodstuff. Choice data come from 421 banana‐consuming households randomly selected from three regions of Uganda. A latent class model is used to investigate the heterogeneity in consumers’ preferences for selected attributes related to the banana and to profile consumers who are more or less likely to accept GM bananas. Our results reveal that there is significant heterogeneity in consumer preferences across our sample. GM bananas are valued the most by poorer households located in the rural areas of the Eastern region. These food‐insecure households would experience the highest benefits (i.e., welfare gains) from the commercial release of GM bananas. In contrast, urban consumers are less accepting of GM bananas, and they would experience significant welfare losses if GM banana is released. According to our welfare estimates, both the total welfare benefits acquired by the gainers and the total welfare losses borne by the losers of this technology are significant and large. These results suggest the need for further investigation of the overall welfare effects of the introduction of GM bananas on the Ugandan society as a whole.  相似文献   

13.
We examine the economic effects of the introduction of consumer-oriented genetically modified (GM) products into the food system by developing a model of heterogeneous consumers and producers that allows for vertical and horizontal differentiation between the products available to consumers. The model facilitates the estimation of consumer and producer surpluses in the product/utility and product/net returns spaces. Results show that the introduction of consumer-oriented GM products can change the relationship between GM and conventional and organic products from one of vertical to one of horizontal product differentiation and can enhance both economic welfare and the market acceptance and growth of agricultural biotechnology.  相似文献   

14.
Modern biotechnology will generate crops with higher yields and enhanced resistance to pests and diseases. In the case of perennial crops, the age composition of the present stand, the farmers' willingness to invest, and the yield profiles of old and new trees determine the speed of adoption of the new technology and the timing of the effects on supply and demand conditions. We adapt conventional welfare measures to account for these factors in the Assessment of research induced supply shifts. The application to cocoa in Malaysia shows that consumers and adopting producers gain and non-adopters lose. Overall, 72% of the welfare gains go to the consumers.  相似文献   

15.
Obesity is a public health problem in the United States that has been linked to excess sweetener consumption. The American Heart Association (AHA) recommends no more than 6–9 teaspoons/capita/day, while the U.S. Food and Drug Administration (FDA) recommends 200 calories/capita/day of caloric sweetener consumption. Both recommendations are well below the reported 2016 sweetener consumption levels. We quantify the input tax rates needed to reduce the current excess sweetener consumption level to the AHA and FDA recommended standards. We calculate the joint tax in the United States on two major sweeteners, sugar and High Fructose Corn Syrup (HFCS), to be 31 and 24 cents per pound, respectively, based on the AHA standard, and 19 and 17 cents per pound, respectively, using the FDA standard. These taxes would be roughly the magnitude of the existing sugar and HFCS prices. In both cases, the tax incidence on producers is much smaller than on consumers. Our focus is very different from past studies in that it deals with the effect of taxes on inputs to meet the recommended target rather than a selective tax (sugar‐sweetened beverage tax). If a sweetener tax were implemented, U.S. sugar and HFCS producers would lose US$398–US$489 and US$683–US$844 million per year, respectively.  相似文献   

16.
Genetically modified (GM) crops are popular in many regions of the world, but their deployment in Africa is hindered by safety concerns and regulatory issues, although the continent is in dire need of boosting its food production. Although consumers' acceptance of GM food has been analyzed in many continents, no such studies have been conducted in Africa. Therefore, a survey of 604 consumers was conducted in Nairobi, Kenya, in 2003, to gauge consumers' awareness of GM crops, their willingness to pay (WTP) for GM food, and the factors that influence their WTP. Consumers' knowledge of GM crops was limited and only 38% of the 604 respondents were aware of GM crops. People in higher education and income groups were more aware than others. Regardless, people were generally appreciative of the technology, and a large majority (68%) would be willing to buy GM maize meal at the same price as their favorite brand. Consumers were, however, concerned about possible side effects, especially on the environment and biodiversity. WTP was estimated using a double‐bounded dichotomous choice model, and the mean WTP was found to be 13.8% higher than the average price of non‐GM maize meal. Perceptions of health risk, and ethical and equity concerns had a negative influence on the likelihood of purchasing GM maize meal, whereas trust in government to ensure food quality had a positive influence on WTP. People with at least some secondary education and those in the high‐income category were more likely to purchase GM maize meal at the same price. The study concludes that, because awareness is still low, appropriate communications are needed to involve the consumer in the debate. Consumers' acceptance in this study was high, but the research needs to be expanded to rural areas, where most consumers live, and other survey methods need to be explored.  相似文献   

17.
The purpose of this article is to examine the system-wide effects of the introduction of genetically modified (GM) products with and without labeling and to compare these two regimes to a third regime where GM products are not present either because they have not yet been developed or because they have been banned. For each regime, the decisions and welfare of consumers, producers, and life science companies are examined. The article explicitly incorporates the consumer response to the introduction of GM technology and considers different market structures of the life science sector.  相似文献   

18.
We estimate the perceived costs of legal requirements (‘coexistence measures’) for growing genetically modified (GM) Bt maize in Germany using a choice experiment. The costs of the evaluated ex‐ante and ex‐post coexistence measures range from zero to more than €300 per measure and most are greater than the extra revenue the farmers in our survey expect from growing Bt maize or than estimates in the literature. The cost estimates for temporal separation, the highest in our evaluation, imply that the exclusion of this measure in Germany is justified. The costliest measures of the ones that are currently applied in Germany are joint and strict liability for all damages. Our results further show that neighbours do not cause a problem and opportunities for reducing costs through agreements with them exist. Finally, we find that farmers’ attitudes towards GM crops affect the probability of adoption of Bt maize. Our results imply that strict liability will deter the cultivation of Bt maize in Germany unless liability issues can be addressed through other means, for example, through neighbours agreements.  相似文献   

19.
Landscape Clubs: Co-existence of Genetically Modified and Organic Crops   总被引:1,自引:0,他引:1  
The possibility of increased production of genetically modified (GM) crops in agriculture accentuates the need to examine the feasibility of GM and non‐GM technologies co‐existing on a common physical landscape. Using the theory of clubs, this paper examines the possibility of co‐existence for GM and organic wheat technologies through the formation of an organic club with an endogenously determined buffer zone. Given the available data on prices, and yields, it is shown that a club can be created in which GM and organic agricultural production technologies can economically co‐exist in the same physical landscape. Specifically, co‐existence results in an increase in economic welfare over a situation where only GM technology is used but is not Pareto superior because producers in the buffer zone will incur injury. We show that organic producers in the club can compensate producers in the buffer zone and still be better off. Hence, the compensation principle holds. La possibilité de production accrue de cultures génétiquement modifiées (GM) accentue la nécessité d'examiner la faisabilité de coexistence des technologies GM et non GM dans un même paysage agricole. À l'aide de la théorie des clubs, le présent article a examiné la possibilité de coexistence des technologies de culture de blé GM et de blé biologique en créant un club ?biologique? comprenant une zone tampon déterminée de façon endogène. Compte tenu des données disponibles concernant les prix et les rendements, il est montré qu'il est possible de créer un club au sein duquel les technologies de production de cultures biologiques et GM peuvent économiquement coexister dans un même paysage naturel. Spécifiquement, la coexistence engendre une augmentation du bien‐être économique par rapport à une situation où seule la technologie GM est utilisée, mais elle n'est pas Pareto supérieure parce que les producteurs dans la zone tampon subiront des dommages. Nous montrons que les producteurs de cultures biologiques membres du club peuvent indemniser les producteurs de la zone tampon tout en demeurant en bonne position. Le principe de compensation tient donc.  相似文献   

20.
This paper develops a model of differentiated consumers to examine the consumption effects of genetic modification (GM) under alternative labelling regimes and segregation enforcement scenarios. Analytical results show that if consumers perceive GM products as being different than their traditional counterparts, GM affects consumer welfare and, thus, consumption decisions. When the existence of market imperfections in one or more stages of the supply chain prevents the transmission of cost savings associated with the new technology to consumers, GM results in welfare losses for consumers. The analysis shows that the relative welfare ranking of the ‘no labelling’ and ‘mandatory labelling’ regimes depends on: (i) the level of consumer aversion to GM products; (ii) the size of marketing and segregation costs under mandatory labelling; (iii) the share of the GM product in total production; and (iv) the extent to which GM products are incorrectly labelled as non‐GM products.  相似文献   

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