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1.
Limited empirical evidence exists on how multiple binding constraints influence the adoption of improved technologies by smallholder farmers. This article uses the case of groundnut variety adoption in Uganda to investigate the role of information, seed supply, and credit constraints in conditioning technology uptake. New data from a household survey in seven groundnut growing districts (n = 945) indicate that 8% of farmers lack information on new varieties, while 18% and 6% of farmers, respectively, cannot adopt mainly due to seed supply and capital constraints. A tobit‐type specification that considers all nonadopters as being uninterested in the technology (i.e., corner solutions) would lead to inconsistent parameter estimates and incorrect conclusions in this context. We therefore estimate a modified multi‐hurdle specification of demand for new varieties, taking into account how information, seed supply, and capital constraints jointly determine adoption probability and intensity. The study reveals new empirical insights on why agricultural technology adoption in Africa has lagged behind: slow uptake is not mainly due to a lack of economic incentives, but rather a reflection of information, seed supply, and credit constraints that prevent farmers from translating their desired demand into adoption of modern varieties. Policy implications are discussed.  相似文献   

2.
This paper explores farmers’ willingness to adopt genetically modified (GM) oilseed rape prior to its commercial release and estimates the ‘demand’ for the new technology. The analysis is based upon choice experiments with 202 German arable farmers. A multinomial probit estimation reveals that GM attributes such as gross margin, expected liability from cross pollination, or flexibility in returning to conventional oilseed rape significantly affect the likelihood of adoption. Neighbouring farmers’ attitudes towards GM cropping and a number of farmer and farm characteristics were also found to be significant determinants of prospective adoption. Demand simulations suggest that adoption rates are very sensitive to the profit difference between GM and non‐GM rape varieties. A monopolistic seed price would substantially reduce demand for the new technology. A monopolistic seed supplier would reap between 45% and 80% of the GM rent, and the deadweight loss of the monopoly would range between 15% and 30% of that rent. The remaining rent for farmers may be too small to outweigh possible producer price discounts resulting from the costs of segregating GM and non‐GM oilseed rape along the supply chain.  相似文献   

3.
Determinants of herbicide use in rice production in the Philippines   总被引:1,自引:0,他引:1  
This study identifies farm‐specific and market factors affecting the adoption of herbicides and the level of herbicide use by rice farmers in the Philippines. This requires the application of a modified version of Heckman's two‐step method to estimate a random‐effects double‐hurdle model for unbalanced panel data. The age of the farmer, household size, and irrigation use are significant determinants of the decision of farmers to adopt herbicides as an alternative to manual weeding, while economic variables such as the price of herbicides, total income, and access to credit determine the level of herbicide use. Determinants of both adoption and level are land ownership, farm area, and the method of crop establishment. These results are potentially relevant when designing policies to reduce excessive herbicide use or to encourage the adoption of alternative weed control methods such as integrated weed management.  相似文献   

4.
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   

5.
Adoption of improved maize varieties in the hills of Nepal   总被引:3,自引:0,他引:3  
Maize (Zea mays L.) is the most important cereal crop in the hills of Nepal, where the grain is used for human consumption and the stover for animal fodder. Maize farms are small, and population pressure necessitates the intensification of existing farming systems. Maize research directed at developing technologies for maize production began in Nepal in 1965. In 2000, a survey was carried out in two districts to determine the current level of adoption of improved maize production practices. In each of these districts, remote and accessible village development committees (VDCs) were surveyed. Questionnaires were administered to 54 randomly selected households in each VDC. A Tobit analysis was used to determine socio‐economic, physical and technology factors that influence the use of improved varieties by farmers. All households use composted farmyard manure, and in the more accessible areas, urea as part of their soil fertility management strategy. Use of improved varieties was less than 60% for all VDCs and only 15% in the most remote VDC. In three of the four VDCs, adoption of improved varieties primarily occurred during the past 5 years. Based on a Tobit analysis, Khet land area, ethnic group, years of fertiliser use, off‐farm income, and contact with extension significantly and positively affected adoption of improved varieties. Farmers in VDCs in central Nepal reported lack of seed to be the major constraint to the adoption of improved varieties, while lack of knowledge of new varieties was the major constraint for farmers in the western VDCs. The results from this survey suggest that the strategy for improving the adoption of new varieties will differ depending on infrastructure and the socio‐economic conditions of the farmers in a given area.  相似文献   

6.
Export agriculture offers potentially high returns to smallholder farmers in developing countries, but also carries substantial market risk. In this article we examine the intertemporal welfare impact of the timing of a farmer's entry into the export pineapple market in southern Ghana. We examine whether farmers who never cultivated pineapple are better or worse off than farmers who decided to adopt pineapple earlier or later relative to their peers and experienced a significant adverse market shock several years prior to our endline survey. We use a two‐stage least squares model to estimate the causal effect of duration of pineapple farming on farmer welfare. Consistent with economic theory, we find that earlier adoption of the new crop brings greater welfare gains than does later uptake. But we find that the gains to later uptake of pineapple—just before the market shock—are small in magnitude, just 0.1 standard deviations of a comprehensive asset index, indicating that the gains to adoption may be precarious and depend on the context, in particular on the severity of prospective market shocks.  相似文献   

7.
In India, pearl millet is a typical subsistence crop. Nonetheless, use of hybrid seeds is widespread. The first pearl millet hybrids were introduced in 1965 by the public sector. Yet, starting in the late 1980s, market liberalisation led to an increasing role of private companies in seed development and distribution. Although several studies showed that proprietary pearl millet hybrids are more productive than public hybrids and open‐pollinated varieties, the impacts of privatisation on farmers’ technology access and overall innovation rates are not yet well understood. This paper analyses the dynamics of adoption using duration models and farm survey data collected in the state of Maharashtra. The results show that education, short distances to main information sources and good market infrastructure speeded up the adoption of pearl millet hybrids. Likewise, the increasing role of private seed companies had a positive and accelerating effect on technology diffusion in the small farm sector.  相似文献   

8.
How much might the potential economic benefit from enhanced farm productivity associated with crop biotechnology adoption by Australia and New Zealand (ANZ) be offset by a loss of market access abroad for crops that may contain genetically modified (GM) organisms? This paper uses the Global Trade Analysis Project (GTAP) model to estimate effects of other countries' GM policies without and with ANZ farmers adopting GM varieties of various grains and oilseeds. The gross economic benefits to ANZ from adopting GM crops under a variety of scenarios could be positive even if the strict controls on imports from GM‐adopting countries by the European Union are maintained, but not if North‐East Asia also applied such trade restaints. From those gross economic effects would need to be subtracted society's evaluation of any new food safety concerns and negative environmental externalities (net of any new environmental and occupational health benefits), as well as any extra costs of segregation, identity preservation and consumer search.  相似文献   

9.
This article examines the driving forces behind farmers’ decisions to adopt improved pigeonpea and maize and estimates the causal impact of technology adoption on household welfare using data obtained from a random cross‐section sample of 613 small‐scale farmers in Tanzania. We use seemingly unrelated and recursive bivariate probit regressions to test the endogeneity and joint decision making of pigeonpea–maize production. A double hurdle model is used to analyze the determinants of the intensity of technology adoption conditional on overcoming seed access constraints. To address the impact of adoption on welfare, the article employs both propensity score matching and switching regression techniques. Results from bivariate probit models show that unobservable factors cause both decisions to be correlated but the finding does not support the conjecture that both decisions are made jointly. Overall the analysis of the determinants of adoption identifies inadequate local supply of seed, access to information, human capital, and access to private productive asset as key constraints for pigeonpea technology adoption. The causal impact estimation from both the propensity score matching and switching regression suggests that maize/pigeonpea adoption has a positive and significant impact on income and consumption expenditure among sample households.  相似文献   

10.
We examine smallholder farmers’ willingness to pay for agricultural technology and whether information is a constraint to adoption of certified maize seed in Northern Uganda. The uptake of improved maize varieties by smallholder farmers in Uganda remains persistently low, despite the higher yield potential compared to traditional varieties. A recently growing body of literature identifies information constraints as a potential barrier to adoption of agricultural technologies. We used incentive compatible Becker‐DeGroot‐Marschak auctions to elicit willingness to pay for quality assured improved maize seed by 1,009 smallholder farmers, and conducted a randomised evaluation to test the effect of an information intervention on farmers’ knowledge of seed certification. Our results show that the randomised information treatment enhanced farmers’ knowledge of certified seed. However, using the information treatment as an instrumental variable for knowledge, we find no evidence of a causal effect of knowledge on willingness to pay, suggesting that even though farmers are information constrained, this constraint does not affect adoption of certified seed directly. Nevertheless, only 14% of sampled farmers were willing to pay the market price, which corresponds closely with actual observed demand for certified seed in the previous season. This suggests that there are other barriers to adoption than information and awareness.  相似文献   

11.
Does agricultural extension pay?   总被引:1,自引:0,他引:1  
Compared to studies evaluating the benefits from agricultural research, there are relatively few empirical studies of the net economic benefits of agricultural extension, and even fewer that consider both public and private sector extension effort. In this study we examine regional differences in the adoption of lupins in Western Australia (WA) in order to estimate the net economic benefits of public and private sector extension. Impacts of extension and other variables on adoption were analysed for 40 shires using multivariate regression analysis. The results suggest that both public and private extension activities influenced farmer uptake of lupins, particularly by bringing forward the start time of the diffusion curve. Economic benefits of extension, based on the statistical analysis, were combined with costs of extension estimated from public sector records and surveys of private sector extension agents and used to estimate the net present value of extension investments by the public and private sectors in the study area.  相似文献   

12.
In the continuing debate over the impact of genetically modified (GM) crops on farmers of developing countries, it is important to accurately measure magnitudes such as farm‐level yield gains from GM crop adoption. Yet most farm‐level studies in the literature do not control for farmer self‐selection, a potentially important source of bias in such estimates. We use farm‐level panel data from Indian cotton farmers to investigate the yield effect of GM insect‐resistant cotton. We explicitly take into account the fact that the choice of crop variety is an endogenous variable which might lead to bias from self‐selection. A production function is estimated using a fixed‐effects model to control for selection bias. Our results show that efficient farmers adopt Bacillus thuringiensis (Bt) cotton at a higher rate than their less efficient peers. This suggests that cross‐sectional estimates of the yield effect of Bt cotton, which do not control for self‐selection effects, are likely to be biased upwards. However, after controlling for selection bias, we still find that there is a significant positive yield effect from adoption of Bt cotton that more than offsets the additional cost of Bt seed.  相似文献   

13.
We examine factors affecting the adoption of improved cassava varieties of 217 households in the Cauca Department in southwest Colombia. Using DNA fingerprinting through Single Nucleotide Polymorphisms (SNPs), we identified different cultivars in farmers fields. We also used this information to remove possible bias in the adoption model that could have resulted from a misclassification of improved varieties (IVs). As a result, we found that farmers substantially overestimate their use of IVs and there are important differences in the determinants of adoption between farmer self‐identification and DNA fingerprinting. This finding implies that the incorporation of DNA fingerprinting in IV adoption studies is important to ensure the accuracy of future agricultural economic research and the relevance of subsequent policy recommendations.  相似文献   

14.
As rice constitutes the major share in cereal consumption in South and East Asian countries that ranges from as low as 40 per cent in India to 97 per cent in Myanmar, to ensure food security, governments in these countries are encouraging farmers to adopt hybrid rice. This is mainly because hybrid rice provides a yield gain of 15–20 per cent over conventionally bred varieties in general. Yet, despite strenuous government efforts, farmers’ adoption rates have remained low in India, Bangladesh and Vietnam compared with China. Although studies often claim that higher seed costs and inferior grain quality are the major factors limiting hybrid rice adoption, very few studies examine the importance of socio‐economic factors and infrastructure in the adoption of hybrid rice. Using Bangladesh as a case, a comparative analysis has been made on the adoption of hybrid and modern varieties relative to traditional rice varieties and land allocation to these varieties. Econometric results indicate that general land characteristics, loan facilities and general infrastructure, such as roads, irrigation facilities and the availability of government‐approved seed dealers, significantly influence the adoption of hybrid and modern rice varieties and land allocation to these varieties compared with traditional varieties.  相似文献   

15.
New Rice for Africa (NERICA) was developed by the Africa Rice Center by crossing high-yielding Asian rice (Oryza sativa L.) with locally adapted African rice (Oryza glaberrima Steud.). Community-based seed production of NERICA varieties was introduced in a village in central Benin in 2006 through seed dissemination projects. It was reported that high-adoption rates of these varieties were mainly due to high demand by development projects for seed dissemination, and to incentives (i.e. selling the rice seed at a higher than local market price to a local extension service) for farmers to grow NERICA varieties. A follow-up survey was undertaken after the seed dissemination projects ended to examine the change in the cultivation of NERICA varieties. About half of the farmers had ceased cultivation of NERICA varieties in 2011. The reasons for abandonment were the combined effects of reduced seed demand and low yields, which were attributed to a lack of access to credit and training on NERICA cultivation practices. The majority of the farmers did not abandon rice cultivation, but grew other high-yielding varieties, including one aromatic variety for which there was market demand. We conclude that to avoid immediate reductions in the adoption of new varieties after projects are terminated and to enhance agricultural sustainability, the varieties should be introduced in conjunction with appropriate group training on their cultivation, and the project should target farmers who do not have off-farm businesses. Furthermore, access to credit should also be enhanced, and the marketability of the varieties should be assessed.  相似文献   

16.
There is a lack of evidence for impact at scale of vegetable research and development, although the importance of vegetables for human nutrition and smallholder incomes is generally understood. We therefore study adoption and impact of improved tomato and African eggplant varieties developed through international agricultural research, released by national agricultural research and extension systems, and supplied to farmers by private seed companies in East and Southern Africa from 1990 to 2014. The study finds that in 2014, varieties developed by the World Vegetable Center accounted for 50% of tomato and 98% of African eggplant commercial seed production in East and Southern Africa. For Tanzania alone, investment in crop improvement generated economic gains of US$ 255 million for tomato and US$ 5 million for African eggplant up to 2014. The internal rate of return is 26% for tomato and 12% for African eggplant, though we project the latter to increase to 26% by 2024 as the variety was released only in 2007. These findings support the view that agricultural policy and investment reoriented towards contemporary nutritional challenges will give high returns to investment.  相似文献   

17.
Adoption rates of improved or modern varieties (MV) of sorghum in eastern Ethiopia are generally low. Although these MV may represent an effective means of coping with droughts, given their early maturing traits, landraces could prove to be more drought‐tolerant and better adapted to marginal production conditions. Whether MV adoption is a risk reducing technology is very much an empirical question which this article investigates using a unique dataset from eastern Ethiopia in a year of extreme weather conditions. Results show that risk‐factors coupled with access to markets and social capital drive farmers’ decisions to adopt MVs. On the one hand, it appears that farmers use MVs to mitigate moderate risks. On the other hand, farmers who have been most vulnerable to extreme weather events are less likely to use MVs suggesting that MV adoption does not necessarily represent an effective means of coping with drought. Finally, findings show that MV growers are more likely to be affected by sorghum failure once controlling for exogenous production factors.  相似文献   

18.
Why do men and women adopt agricultural technologies at different rates? Evidence from Ghana suggests that gender‐linked differences in the adoption of modern maize varieties and chemical fertilizer result from gender‐linked differences in access to complementary inputs. This finding has important policy implications, because it suggests that ensuring more widespread and equitable adoption of improved technologies may not require changes in the research system, but rather introduction of measures that ensure better access for women to complementary inputs, especially land, labor, and extension services.  相似文献   

19.
The economic impact of bean disease resistance research in Honduras   总被引:2,自引:0,他引:2  
This paper presents evidence of recent adoption rates of disease resistant bean varieties (RVs), the farm‐level benefits of RV adoption, and the ex post rate of return to disease resistant bean research in Honduras. Results from a farm‐level survey in 2001 in the two principal bean‐producing regions of the country show that 41–46% of bean farmers (depending upon the season) have adopted an RV, and that adoption is neutral with respect to farm‐size and market orientation. An expected utility framework was used to estimate the farm‐level benefits of RV adoption, using a combination of experimental trial and farm‐level survey data. Adopters gain the equivalent of 7–16% (depending on the variety) in bean income from the yield loss averted through RV use. The ex post rate of return to disease resistant bean research in Honduras from 1984 to 2010 is 41.2%.  相似文献   

20.
Restrictions on input use frequently accompany the granting of institutional credit to farmers in developing agriculture. A general economic framework is suggested to analyze the net social benefits of such a policy. The paper discusses the potential for manipulating the policy variables to foster more rapid adoption of new agricultural technology. An empirical analysis of the impact of a supervised credit programme in Guatemala on farm performance and farmer decision-making is presented.  相似文献   

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