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1.
We use DNA‐fingerprinting to estimate the poverty reduction effect of adoption of improved cassava varieties in Nigeria. We estimate the counterfactual household income distribution of cassava producers by combining farm‐level treatment effects with a market‐level model. Our results suggest that adoption of improved cassava varieties has led to a 4.6 percentage point reduction in poverty, though this is sensitive to the measurement of adoption status. Therefore, accurate measurement of adoption is crucial for a more credible estimate of the poverty reduction effect of adoption. Our analysis also suggests that farmers who are more likely to be adopters are also likely to face higher structural costs. Addressing structural barriers that make improved technologies less profitable for the poor would therefore be important to increase the poverty reduction effect of improved cassava varieties.  相似文献   

2.
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   

3.
Studies of improved seed adoption in developing countries are almost always based on household surveys and are premised on the assumption that farmers can accurately self-report their use of improved seed varieties. However, recent studies suggest that farmers’ reports of seed varieties planted, or even whether the seed is local or improved, are sometimes inconsistent with the DNA fingerprinting results of those crops. We use household survey data from Tanzania to test the alignment between farmer-reported and DNA-identified maize seed types planted. In the sample, 70% of maize seed observations are correctly reported as local or improved, while 16% are type I errors (falsely reported as improved) and 14% are type II errors (falsely reported as local). Type I errors are more likely to have been sourced from other farmers, rather than formal channels. An analysis of input use, including seed, fertiliser, and labour allocations, reveals that farmers tend to treat improved maize differently, depending on whether they correctly perceive it as improved. This suggests that errors in farmers’ seed type awareness may translate into suboptimal management practices. The average yield of seed that is correctly identified as improved is almost 700 kg per hectare greater than that of type I errors. This indicates that investments in farmers’ access to information, seed labelling, and seed system oversight are needed to complement investments in seed variety development.  相似文献   

4.
We use a detailed dataset to examine the impact of social networks, conditional on contextual and individual confounders, on farmers' adoption of competing improved soybean varieties in Ghana. Based on the contagion conceptual framework, we employ a spatial autoregressive multinomial probit model to examine how neighbours' varietal and cross-varietal adoption of improved varieties affect a farmer's adoption decision in the social network. Our results show that adoption decisions in a network tend to converge on one variety, such that beyond a threshold of adopting neighbours of that improved variety, the cross-varietal effects tend to lose significance in the network. If the shares of adopting neighbours of the improved varieties are equal, we find evidence that farmers are not more likely to adopt either improved variety compared to farmers with no neighbours who have adopted the improved varieties. The findings demonstrate the significance of neighbourhood effects in the adoption of competing technologies.  相似文献   

5.
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   

6.
We examine adoption of drought tolerant (DT) maize varieties using a four‐round panel dataset from six districts in Malawi. There is an increase in adoption of DT maize from 3% in 2006 to 43% in 2015 in our data. We focus on the effect of past drought exposure on adoption and the likelihood of DT maize being distributed under the Farm Input Subsidy Programme (FISP). Results show that past exposure to drought increases the probability of DT maize seed being distributed through FISP. Farmers who accessed maize seed subsidy coupons and were previously exposed to late season dry spells are more likely to use the seed subsidy coupon to redeem DT maize seed. The likelihood of adoption and adoption intensity (area under DT maize) are positively influenced by previous early season dry spells and access to seed subsidy. Previous late season droughts also positively affect adoption intensity. On the other hand, area share under DT maize is positively correlated with early season dry spells and past exposure to late season dry spells but negatively related to seed subsidy. FISP in Malawi appears to have stimulated adoption of DT maize directly through subsidy and indirectly through generating farmers’ experiences of the performance of DT varieties under drought conditions.  相似文献   

7.
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   

8.
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   

9.
This paper summarises research into factors contributing to low levels of adoption of improved maize varieties in Honduras. Empirical analysis was based on an agricultural household model which explicitly incorporates variety characteristics into the household's optimisation process. We considered a multitude of production and consumption characteristics valued by farmers, as well as an array of household socioeconomic characteristics and measures of village‐specific marketing costs. Empirical results indicated that marketing costs and production characteristics are important explanators of variety choice, whereas consumption characteristics are not, and that information deficits may be an important limiting factor to adoption of improved varieties.  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.
In Tanzania, milk production under smallholder farming systems is season sensitive, fluctuations of feeds in both quantity and quality being the major driver. A dry season decline in milk production of over 40% due to feed scarcity is a common phenomenon. Adoption of improved feed production, conservation and utilization technologies and practices in dairy farming communities is poor. This review work was based on a key question which states “Why is adoption of improved dairy nutrition technologies and practices in Tanzania still poor despite being promoted for decades?”. We have shown that major opportunities for curbing dry season animal feed shortage include on-farm optimization of production and use of high yielding pasture varieties including napier grass (Pennisetum purperium Schumach.) and leguminous fodder species. Crop residues in particular maize stover needs to be optimized for effective dry season feeding. The major reasons for low adoption of proven technologies include limited technical knowhow among smallholder dairy farmers augmented by limited extension services and technological costs. For enhancing sustainable uptake; we suggest promotion of on-farm research, public-private partnerships and dairy farmers’ cooperative associations. These are vital for facilitating smooth access to information, investment capital, reliable inputs and markets among the smallholder dairy farmers.  相似文献   

12.
Many studies detail constraints deemed responsible for the limited adoption of new technologies among smallholder farmers in sub-Saharan Africa. By contrast, here we study the conditions that led to the remarkably fast spread of improved chickpea varieties in Ethiopia. Within just seven years, the adoption rate rose from 30 to 80% of the farmers. A combination of factors explains the rapid uptake. Their attraction lay in superior returns and disease resistance. Chickpea was already an important crop for rural households in the studied districts, for both cash income and consumption. Good market access and an easy accessibility of extension services advanced the adoption process. Thus, an attractive technology suitable for rural households in a conducive environment enabled adoption. Our findings prompt us to stress the importance of tailoring agricultural innovations to the realities and demands of rural households, and the need to design and deploy interventions on the basis of ex-ante knowledge on factors potentially determining their success or failure.  相似文献   

13.
Adoptions of improved technologies and production practices are important drivers of agricultural development in low-income countries like Nepal. Adopting a broad class of such technologies and practices is often critical for meeting the multifaceted goals of efficiency, profitability, environmental sustainability, and climate resilience. This study aims to address the knowledge gaps that still exist concerning what determines the adoption of improved technologies and production practices, the factors affecting their diffusion, the impact of interventions on productivity and crops grown, and the variability of impact within a particular country context. In this paper we address these questions using data collected as part of the USAID-led Knowledge-Based Integrated Sustainable Agriculture in Nepal (KISAN) project. We adopted a multistage sampling technique and surveyed 988 beneficiary households and 997 non-beneficiary households in KISAN intervention districts and non-intervention districts. Our findings suggest that, in Nepal, adoption of improved technologies and practices is significantly increased by improved access to markets, private sector involvement in selling improved seeds and disseminating information, membership in progressive farmers groups and cooperative societies, participation in agricultural training and farm visits, provision of subsidies for seeds, and access to credit. We also found the probability of the adoption of improved practices to be affected by farmers’ sources of information; for instance, the adoption of improved practices was increased when farmers obtained information from informal sources, cooperatives/farmers organizations, and public and private extension programs. The effects of KISAN projects vary significantly across the different crops grown, based on the evaluation models that address self-selection of both project participation and crop choices. These implications may also apply to other parts of the world facing similar challenges as Nepal, where limited market access, insufficient knowledge and resource capacity of farmers constrain their adoption of improved technologies and practices in agriculture.  相似文献   

14.
The objective of this paper is to test the hypothesis that farmer perceptions of technology-specific characteristics significantly condition technology adoption decisions. Earlier adoption studies have not considered this in the analysis of the determinants of adoption decisions. The omission of farmers' evaluation of technology-specific attributes may bias the results of factors conditioning adoption choices. A Tobit model was used to test this hypothesis using a stratified random sample of 124 mangrove swamp rice farmers in Sierra Leone. The issue investigated is the adoption of improved mangrove swamp rice varieties. The estimated model results show that farmer perceptions of the technology-specific attributes of the varieties are the major factors determining adoption and use intensities. Indicators of adoption determinants traditionally used in adoption-diffusion studies were found not to be important in driving adoption decisions. Therefore, there is need for adoption studies to consider farmers' perceptions of technology-specific attributes in the assessment of technology adoption decisions.  相似文献   

15.
Farmers in developing countries can dramatically improve their productivity by adopting new plant varieties. Yet, informational barriers often mean adoption rates remain low. In this study, we focus on how learning from others represents one means of removing informational barriers. We capture the effect of social learning through an explicitly spatial econometric model applied to farm‐level maize adoption rates in Mozambique. We find that social learning is significant and can help explain the apparent clustering of adoption among farmers. Agencies interested in promoting variety adoption, therefore, would be well served to leverage the strength of existing information networks, rather than imposing solutions that work against interfarmer information flow.  相似文献   

16.
Dry‐land legumes, well adapted to drought‐prone areas, have largely been neglected in the past despite the good opportunities they offer for income growth and food (and nutritional) security for the poor. This study evaluated the adoption and impact of two farmer and market‐preferred and disease‐resistant pigeonpea varieties that were developed and promoted in semi‐arid Tanzania. The new varieties were resistant to fusarium wilt, a fungal disease devastating the crop. However, farmers wanting to adopt new varieties did not adopt due to seed access constraints and under‐developed seed delivery systems. Adoption of new varieties is therefore analyzed using an augmented double hurdle model that allows estimating variety adoption conditional on seed access thresholds accounting for the additional information on sample separation. The study identifies the crucial role of seed access (local supply), extension, education, participatory decision making, capital, and household assets in determining adoption. The social economic benefits of the technology and policies for improved seed access were further analyzed using the extended economic surplus method (DREAM model). Even under restrictive assumptions, overall discounted benefits were found to be quite attractive, indicating the need for additional efforts to scale‐up the success story. Analysis of changes in research benefits from relaxing the seed access constraint showed that net gains would increase by up to 30% if farmer access to improved seeds can be assured. Smallholder farmers are the major beneficiaries along with consumers and rural net‐buyers who gain from productivity‐induced lower market prices.  相似文献   

17.
Drought tolerant (DT) maize varieties have received massive support in sub‐Saharan Africa because of their potential to protect smallholder farmers against drought‐related maize yield losses. Using four waves of household farm panel data from six districts in Malawi, we examine the impact heterogeneity of this technology on maize productivity using a continuous treatment approach. We find strong evidence of positive correlation between maize yield and adoption of DT maize varieties. On average, an increase by one hectare in the area allocated to DT varieties increases maize yield by 547 Kg/ha representing a 44% increase from the average maize yield of 1,254 Kg/ha for our sample. Our findings give evidence that DT maize technology has potential to protect smallholder farmers against drought‐related production losses. Policies that promote increased allocation of maize area to DT maize hold potential to enhance food security. Smallholder farmers especially in drought‐prone areas should be encouraged to allocate at least one‐third of the maize plot to DT varieties while breeders continue with the efforts of breeding a DT variety that is not only drought tolerant but also adapted to all weather conditions. More importantly, the government should ensure provision of timely ex ante weather information to guide farmers on decision‐making with respect to maize varietal choices.  相似文献   

18.
We propose an approach to model the derived demand for crop varieties among semi‐subsistence farmers in a developing economy, and apply it to smallholder banana producers in Uganda. We model variety planting decisions as being composed of an extensive margin decision to grow a subset of locally available varieties (variety choice); and an intensive margin decision about the scale or extent of variety cultivation per farm (variety demand). We estimate variety demand equations using a more complete representation of the choice set upon which observed planting decisions are made. Computed elasticities of variety demand with respect to variety attributes indicate that the relative importance of consumption and production attributes varies by location and proximity to markets, from which we draw implications for the social and economic impact of crop improvement. The approach that we propose has broad appeal for analysing adoption decisions for modern or traditional varieties of both major and minor crops in developing countries.  相似文献   

19.
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   

20.
With population growth still at very high rates and large-scale commercial farmers and cattle ranchers owning much of the more fertile valley land, small-scale farmers are concentrated on increasingly marginal, steeply sloping hillsides in Central America. The continuing soil erosion and land degradation in these low-input staple crop production hillside farming systems lead many to be pessimistic about increasing the agricultural incomes of these farmers. However, this study shows that the appropriate combination of improved technologies and agricultural policy or alternative production diversification strategies can improve the incomes of small-scale hillside farmers in southern Honduras by over 50%. The technology components considered are stone walls and ditches combined with living tree barriers to prevent erosion of the hillsides, and a package of improved sorghum seed, seed treatment, and modest doses of nitrogenous fertilizer. A whole-farm mathematical programming framework is used to determine the potential farm-level income effects of the soil-conservation and seed-fertilizer technologies. The main conclusion is that erosion-control devices and yield-increasing crop varieties and fertilizer are an effective technology introduction strategy for the erosion-prone hillside landholdings found in many areas of Central America. If policy actions or diversification strategies for disposal of surplus grain are found which are effective in reducing the risk of low income from cereal price reductions in high-production years, adoption of the improved technologies is shown to be profitable for small-scale farmers. Another benefit not explicitly considered would be to slow the very rapid growth of urban poverty in these countries. Sensitivity analysis results indicated that neither risk aversion nor the increased availability of crop land or initial cash have any substantial effects on the predicted adoption level of the improved technologies, or on their income impacts for these farmers.  相似文献   

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