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1.
The ‘high speed’ rotavator is used for shallow tillage to create a fine tilth and incorporate crop residues, often with a single tractor pass. Rotavator tillage has spread quickly in many parts of South Asia, despite short-term experimental trials suggesting deteriorating soil quality and crop yield penalties. Evidence of rotavator impacts on farmer fields across soil gradients and time is largely absent. From a farm household survey conducted among wheat farmers in Nepal, we estimate wheat yield and profitability outcomes for rotavator adopters and non-adopters using propensity score matching. We find that rotavator adoption leads to inferior outcomes, despite significant cost savings for land preparation (US$ 11–15 per hectare). With rotavator adoption, farmers lose about 284–309 kg of wheat grain and about US$ 93–101 of profits on average per hectare per season, and these penalties increase with longer-term use of the technology. Adoption of rotavator appears to be driven by the cost and time savings for land preparation. Against this backdrop, new policy and extension efforts are required that discourage rotavator use and favour more sustainable tillage technologies.  相似文献   

2.
This article analyzes adoption and impacts of Bt cotton in Argentina against the background of monopoly pricing. Based on survey data, it is shown that the technology significantly reduces insecticide applications and increases yields; however, these advantages are curbed by the high price charged for genetically modified seeds. Using the contingent valuation method, it is shown that farmers' average willingness to pay is less than half the actual technology price. A lower price would not only increase benefits for growers, but could also multiply company profits, thus, resulting in a Pareto improvement. Implications of the sub-optimal pricing strategy are discussed.  相似文献   

3.
There is a broad literature on the impact of Bt cotton adoption in different countries, but few studies have explicitly looked at environmental and health effects from an economic perspective. We analyse the impact of Bt cotton on environmental efficiency in Pakistan, using farm survey data and a doubly heteroskedastic stochastic production function framework. Negative environmental and health effects of chemical pesticide use are quantified with the environmental impact quotient. Bt‐adopting farms have higher cotton yields, while using lower pesticide quantities and causing less environmental damage. Bt farms are both technically and environmentally more efficient than non‐Bt farms. Bt adoption increases environmental efficiency by 37%. Achieving the same reduction in negative environmental and health impact without Bt would cost conventional cotton farmers US$ 54 per acre in terms of foregone yields and revenues (7% of total revenues). Extrapolating this shadow price of the technology's health and environmental benefits to the total Bt cotton area in Pakistan results in an aggregate value of US$ 370 million. These benefits are in addition to the profit gains for Bt‐adopting farmers. Our results suggest that Bt technology can contribute to sustainable agricultural development.  相似文献   

4.
This article assembles the results of three multicountry surveys on variety performance and adoption patterns to measure the impacts of maize research in West and Central Africa from 1981 to 2005, and uses cost data since 1971 to compute social rates of return on public investments in maize research in the region. Adoption of modern varieties increased from less than 5% of the maize area in the 1970s to about 60% in 2005, yielding an aggregate rate of return on research and development (R&D) investment of 43%. The estimated number of people moved out of poverty through adoption of new maize varieties rose gradually in the 1980s to more than one million people per year since the mid 1990s. Over half of these impacts can be attributed to international maize research at IITA and CIMMYT. The article concludes with a discussion of strategic options to enhance the impacts of maize research in the region.  相似文献   

5.
Bt cotton remains one of the most widely grown biotech crops among smallholder farmers in lower income countries, and numerous studies attest to its advantages. However, the effectiveness of Bt toxin, which depends on many technical constraints, is heterogeneous. In Pakistan, the diffusion of Bt cotton occurred despite a weak regulatory system and without seed quality control; whether or not many varieties sold as Bt are in fact Bt is also questionable. We utilise nationally representative sample data to test the effects of Bt cotton use on productivity. Unlike previous studies, we invoke several indicators of Bt identity: variety name, official approval status, farmer belief, laboratory tests of Bt presence in plant tissue, and biophysical assays measuring Bt effectiveness. Only farmer belief affects cotton productivity in the standard production model, which does not treat Bt appropriately as damage‐abating. In the damage control framework, all Bt indicators reduce damage from pests. Biophysical indicators have the largest effect and official approval has the weakest. Findings have implications for impact measurement. For policy‐makers, they suggest the need, on ethical and productivity grounds, to improve variety information and monitor variety integrity closer to point of sale.  相似文献   

6.
Data from a farm survey and choice experiment are used to value the benefits of Bt cotton in Pakistan. Unlike previous research on the economic impacts of Bt, which mostly concentrated on financial benefits in terms of gross margins, we also quantify and monetize health and environmental benefits associated with technology adoption. Due to lower chemical pesticide use on Bt cotton plots, there are significant health advantages in terms of fewer incidents of acute pesticide poisoning, and environmental advantages in terms of higher farmland biodiversity and lower soil and groundwater contamination. Farmers themselves value these positive effects at US$ 79 per acre, of which half is attributable to health and the other half to environmental improvements. Adding average gross margin gains of US$ 204 results in aggregate benefits of US$ 283 per acre, or US$ 1.8 billion for the total Bt cotton area in Pakistan.  相似文献   

7.
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   

8.
This article proposes a model of technology adoption that integrates demand for individual traits of new technologies with the potential for heterogeneity based on farm and farmer characteristics. The model is applied to recent genetically modified corn adoption data from Minnesota and Wisconsin farmers, using a mixed-multinomial logit (MMNL) model to estimate the effects of traits and farm and farmer characteristics on adoption outcomes. This approach allows explicit recovery of estimates of farmers' shadow prices for individual technology traits. Results show the importance of producer and regional heterogeneity in preferences for seed traits.  相似文献   

9.
On the basis of projected economic and poverty impacts of alternative commodity research programs, this article assessed efficiency and equity tradeoffs and the scope for research resource reallocation in Nigeria. Given the importance of major food staples to both poor and nonpoor households in production and consumption, introducing a poverty dimension revealed no significant shift in priorities compared with those implied by efficiency. The results showed that neither the additional benefits to the poor nor the foregone benefits to society are significant from prioritizing research according to equity—relative to efficiency—criteria. As current priorities are supported by neither efficiency nor equity criteria, however, there is considerable scope for maximizing research benefits to the poor through informed reallocation of research resources. The article concludes with a discussion of the patterns of resource reallocations implied by efficiency and equity criteria.  相似文献   

10.
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   

11.
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   

12.
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   

13.
Agroclimatic conditions and agricultural research and development (R&D) including plant breeding activities by the public sector are some of the most significant exogenous factors in the agricultural sector. However, the effects of the interactions between these two sets of factors on agricultural productivity have not been studied widely in developing countries, despite potentially important implications on their plant breeding strategies. Using three‐wave panel data of agricultural households in Nigeria and spatial data on various agroclimatic parameters, we show that agricultural productivity and technical efficiency at the agricultural household level is significantly positively affected by the similarity of agroclimatic conditions between locations where agricultural households are located, and locations where major plant breeding institutes are located. These results hold after controlling for various socioeconomic characteristics of these households, including their physical distances to the breeding institutes. Findings are robust across parametric and nonparametric specifications such as Data Envelopment Method, and after addressing potential endogeneity of agroclimatic similarity and agricultural inputs variables in the production function. Productivity effects due to the locations of plant breeding institutes and resulting agroclimatic similarity can be potentially sizable given Nigeria's past productivity growth speed.  相似文献   

14.
Employing household survey data covering the periods 1992–1993, 1995–1996, and 1999–2000, this article shows for the case of Uganda that a coffee market liberalization followed by a price boom was associated with substantial reductions in poverty, which could even be sustained when prices went down again. Coffee is not planted by the richest farmers and the gains from higher coffee prices accrued to poorer and richer coffee farmers alike. Nor were poorer farmers hurt disproportionately when prices fell. In addition, we find strong spillovers from coffee production to other agriculture, which tends to favor the poor, and to nonagricultural activities. These multiplier effects are concentrated in coffee regions. In an economic environment characterized by a booming agricultural sector, coffee farmers were able to accommodate the negative price shock, in particular through agricultural diversification. General agricultural growth also cushioned possible negative multiplier effects in coffee regions. Overall, the case of coffee in Uganda thus lends support to the view that agricultural trade liberalization is beneficial for the poor.  相似文献   

15.
This article contributes to a growing body of empirical literature relating credit constraints and incomplete insurance to investment decisions. We use panel data from rural Ethiopia to investigate whether participation in a safety net program enhances fertilizer adoption. Using a difference‐in‐differences estimator and inverse propensity score weighting, we find that participation in Ethiopia's food‐for‐work (FFW) program increased fertilizer adoption in the short run, but not in the long run. Results also indicate that the intensity of fertilizer usage increased with livestock holdings for FFW‐participant households, providing some evidence that the intervention helped asset‐rich farm households more than asset‐poor households. We find no significant effects of free distribution on fertilizer adoption or intensification. Our results are consistent with the hypothesis that safety nets can be viewed as mechanisms that allow households to take on more risk to pursue higher profits. The results highlight the importance of safety net programs, their effectiveness in ensuring farmers that they will be protected against uninsured shocks, and how that assurance can translate into productivity‐enhancing behavior.  相似文献   

16.
The main focus of this article is to explore whether access to selected agricultural water management (AWM) technologies has led to significant reduction in poverty and, if they did so, to identify which technologies had higher impacts. In measuring impact we estimated the average treatment effect for the treated on crop income and measured the differences in consumption expenditures per adult equivalent of those with access and without access using matched data. The estimated average treatment effect was significant and amounted to USD 82 per season. Moreover, there was 24 less poverty incidence among users of AWM technologies compared to nonusers. All technologies were found to have significant poverty reducing impacts with micro dams, deep wells, river diversions, and ponds leading to 37%, 26%, 11%, and 9% reduction in poverty incidence compared to rainfed system. Finally, our study identified the most important correlates of poverty on the basis this we made the policy recommendations to build assets (AWM technologies, livestock, etc); to enhance human resource development and improve the functioning of labor markets for enhanced impact of AWM technologies on poverty.  相似文献   

17.
Sustainable agricultural intensification is an urgent challenge for Sub-Saharan Africa. One potential solution is to rely on local farmers' knowledge for improved management of diverse on-farm resources and integration among various farm enterprises. In this article, we analyze the farm-level impact of one recent example, namely the integrated aquaculture–agriculture (IAA) technologies that have been developed and disseminated in a participatory manner in Malawi. Based on a 2004 survey of 315 respondents (166 adopters and 149 nonadopters), we test the hypothesis that adoption of IAA is associated with improved farm productivity and more efficient use of resources. Estimating a technical inefficiency function shows that IAA farms were significantly more efficient compared to nonadopters. IAA farms also had higher total factor productivity, higher farm income per hectare, and higher returns to family labor.  相似文献   

18.
Evaluating the possible benefits of the introduction of genetically modified (GM) crops must address the issue of consumer resistance as well as the complex regulation that has ensued. In the European Union (EU), this regulation envisions the co‐existence of GM food with conventional and quality‐enhanced products, mandates the labelling and traceability of GM products and allows only a stringent adventitious presence of GM content in other products. All these elements are brought together within a partial equilibrium model of the EU agricultural food sector. The model comprises conventional, GM and organic food. Demand is modelled in a novel fashion, whereby organic and conventional products are treated as horizontally differentiated but GM products are vertically differentiated (weakly inferior) relative to conventional ones. Supply accounts explicitly for the land constraint at the sector level and for the need for additional resources to produce organic food. Model calibration and simulation allow insights into the qualitative and quantitative effects of the large‐scale introduction of GM products in the EU market. We find that the introduction of GM food reduces overall EU welfare, mostly because of the associated need for costly segregation of non‐GM products, but the producers of quality‐enhanced products actually benefit.  相似文献   

19.
This article quantifies the productivity gain from CIMMYT‐released semidwarf bread wheat (Triticum aestivum) cultivars over time, using test plot data from Mexico's Yaqui Valley. Previous studies have shown a deceleration in irrigated wheat yield growth since the 1980s, which could be due to slowing increase in genetic potential. Our results suggest that CIMMYT cultivars contributed a 0.46% annual increase (about 38 kg/ha annually) to wheat yields in the Yaqui Valley, which raised local wheat producers’ revenue by an average of $4 million annually for the period 1990 to 2002, and by approximately $9 million in 2002.  相似文献   

20.
We identify the impact of emergency food aid programs after the 2002 drought in rural Ethiopia on future welfare. Based on a difference-in-differences matching estimator, participation in food-for-work increases growth in total consumption and food consumption eighteen months after the drought. Separately, receiving free food raises growth in food consumption, but, surprisingly, negatively impacts food security. Food-for-work benefited households in the middle and upper tail of the consumption distribution, while the better-targeted free food program benefited the poorest. Evidence suggests these impacts demonstrate accumulated and persistent effects of food aid received in the first twelve months after the drought.  相似文献   

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