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1.
This study investigates farmers’ perception about the severity of loss for three rice crops, identifies their determinants and explores policy implications based on findings. This research employs an ordered probit model to data collected from 1800 farm households from drought-prone and groundwater depleted areas of Bangladesh. This is the first study of its kind.Severity of rice production loss, while differing across all three rice crops, was higher for rain-fed crops. This was broadly consistent with available independent evidence. Geophysical factors, household characteristics, institutional and market accessibility, and household adaptation strategy were key determinants of crop loss. The impact of these factors was specific to the crop and severity of loss.This study has several policy implications involving market, R & D and institutional support based options. Strengthening support systems for institutional and market accessibility, and science driven climate change adaptation strategy including generation and wider dissemination of drought tolerant rice varieties, and enhancing farmers’ capacity to change rice varieties on a regular basis, constitute key areas for policy intervention.  相似文献   

2.
The spatial distribution of modern varieties, and the genes they embody, has economic value because it affects crop productivity from year to year. Since farmers choose varieties based on observable traits rather than the genes they cannot see, a first step in understanding the spatial distribution of genes is to better understand the determinants of the spatial distribution of varieties. In this paper, we have constructed spatial diversity indices from area distributions of modern wheat varieties in Australia and China. We hypothesise that factors explaining variation in these indices are related to farmers' demand for traits and the supply of varieties, given physical features of the production environment. We test these hypotheses using reduced form equations for three concepts of spatial diversity, richness, abundance and evenness, using Zellner's seemingly unrelated regression (SUR). Spatial diversity indicators and analyses of this type, if more fully developed and targeted to address specific policy issues, may assist in monitoring crop genetic diversity or ‘refuge’ targets associated with the diffusion of some genetically modified crops.  相似文献   

3.
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   

4.
This paper investigates the feasibility of changes in cropland-use as an adaptation strategy to minimise the economy-wide costs of climate change on agriculture. Nepal makes an interesting case study as it is one of the most vulnerable agricultural economies within South Asia. We develop a comparative static multi-household computable general equilibrium (CGE) model for Nepal, with a nested set of constant elasticity of transformation (CET) functional forms, to model the allocation of land within different agricultural sectors. Land transformation elasticities in these CET functions are allowed to reflect the ease of switching from one crop to another based on their agronomic characteristics. The results suggest that, in the long run, farmers in Nepal tend to allocate land to crops that are comparatively less impacted by climate change, such as paddy, thereby minimising the economy-wide impacts of climate change. Furthermore, the results reveal that land-use change tends to reduce the income disparity between different household groups by significantly moderating the income losses of marginal farmers. Therefore, it is suggested that policy makers in Nepal should prioritise schemes such as providing climate-smart paddy varieties (i.e., those that are resistant to heat, drought and floods) to farmers, subsidising fertilizers, improving agronomic practices, and educating farmers to switch from crops that are highly impacted by climate change to those that are not, such as paddy.  相似文献   

5.
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   

6.
Crop diversity is a key principle of sustainable food production systems. Yet, inter and intra specific diversification is declining in many regions of the world. In Northern Malawi, a participatory action research project (Soils Food and Healthy Communities) has conducted agroecological co-learning with farmers for over a decade, providing an opportunity to explore farmer management, crop choice and variety selection practices. Farmers who participate receive seed for 0.10 ha of on-farm testing for one growing season and then decide whether to continue to grow the crop. Cropping system diversity, management practices and traits associated with crops grown and lost were assessed through interviews with 198 farm households (757 fields). We found an average of 1.3 species per field and 4.0 crops per farm. This is almost twice the level of diversity in other reports from Malawi smallholder farms. Farmers cited a wide range of preferred groundnut variety traits, as well as concerns (namely, high labour requirements). Both modern and local maize varieties are being grown and those retained were often associated with early maturity or preferred grain quality traits such as storability. Overall, farmers at this Northern Malawi agroecology education site are growing diverse crop mixtures that include traditional as well as modern varieties of maize and groundnut.  相似文献   

7.
This research characterizes the biological diversity of millet crops in the semiarid regions of India at the household and village‐community ( panchayat) scales of analysis, placing that evidence in the context of local seed systems. A set of seed system parameters that span formal and informal exchange and can be measured empirically are proposed. The analysis is based on data collected through sample surveys of farmers and traders in selected sites of Karnataka and Andhra Pradesh, combined with cultivar taxonomies developed with geneticists and applied to seed samples. Findings demonstrate that millet crop diversity levels at both scales of analysis are significantly influenced by seed system parameters, factors which related studies have omitted. In particular, the presence of active local (formal and informal) seed markets enhances millet richness among and within farming communities. Crop improvement strategies oriented toward local seed markets could provide important benefits and incentives to farm households living in these marginal environments. There is a need, however, for an enhanced theoretical understanding of local seed markets in analyzing crop variety choices and the diversity of materials grown in less favored environments.  相似文献   

8.
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   

9.
The case for promoting export‐oriented cash crops in Africa has generally been based on their direct potential contribution to agricultural productivity and small farmer incomes. A relatively neglected avenue of research concerns the synergistic effects that cash cropping can have on other household activities, including food production. The conventional view that cash crops compete with food crops for land and labour neglects the potential for cash crop schemes to make available inputs on credit, management training, and other resources that can contribute to food crop productivity, which might otherwise not be accessible to farmers if they did not participate in cash crop programs. This article builds on previous research by hypothesising key pathways by which cash crops may affect food crop activities and empirically measuring these effects using the case of cotton in Gokwe North District in Zimbabwe. Analysis is based on instrumental variable analysis of survey data on 430 rural households in 1996. Results indicate that—after controlling for household assets, education and locational differences—households engaging intensively in cotton production obtain higher grain yields than non‐cotton and marginal cotton producers. We also find evidence of regional spill‐over effects whereby commercialisation schemes induce second round investments in a particular area that provide benefits to all farmers in that region, regardless of whether they engage in that commercialisation scheme. The study suggests that the potential spill‐over benefits for food crops through participation in cash crop programs are important to consider in the development of strategies designed to intensify African food crop production.  相似文献   

10.
Genetic resources for food and agriculture are the biological basis of world food and nutrition security; and they directly or indirectly support the livelihoods of over 2.5 billion people. Genetic diversity gives a species or a population the ability to adapt to changing environments. For resource-poor farmers, adaptive animal breeds, crop varieties and cultivars adapted to particular micro-niches, stresses or uses are the main resources available to maintain or increase production and provide a secure livelihood. The economic value of genetic diversity for productivity and yield traits is discussed in the literature. However, it is difficult to value many other aspects of agricultural biodiversity as these have both direct and indirect values in terms of qualitative traits such as food, nutrition and environmental uses that include adaptation to low input conditions, co-adaptive complexes, yield stability and the consequent reduction of risk, specific niche adaptation, and in meeting socio-cultural needs. Together, the direct and indirect values of genetic resources for resource-poor farmers are expressed in a range of options in the form of the crop varieties and species they use for managing changing environments.

The value of genetic diversity to resource-poor farmers is seldom captured by markets or addressed by the international research agenda. This paper presents lessons learned from our work over 5–10 years in the Asia and Pacific Ocean (APO) region on participatory crop improvement, home gardens and on-farm management of agricultural biodiversity. The lessons illustrate how farmers adapt genetic resources to suit local environmental conditions. The paper focuses on the value of genetic diversity of selected crop species to meet people's food and other needs. Genetic diversity valued by resource-poor farmers is often maintained, selected and exchanged by local social seed networks. Identification of such genetic resources and their custodians is important if international agricultural research is to contribute to the reduction of poverty. The paper highlights some good practices from case studies that illustrate how such genetic resources could be exploited by informal research and development strategies or participatory plant breeding or for marketing value-added products.  相似文献   

11.
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   

12.
Agricultural diversification and integrated pest management in Bangladesh   总被引:1,自引:0,他引:1  
We study factors associated with a shift toward diversified, high‐valued vegetable crops and the incentives associated with the use of IPM methods for vegetable producers in Bangladesh. The primary objective is to measure how IPM technologies affect the crop and technology choices of low‐income rice farmers. A three‐season household optimisation model is used to study crop and technology choice under price and yield uncertainty. The model is parameterised using data from vegetable farms and experimental IPM trials conducted in Bangladesh. Simulation results show that access to IPM technology and IPM availability combined with access to credit increase household welfare and lead to higher rates of vegetable adoption. Off‐farm employment opportunities work against vegetable cultivation and IPM use by risk‐averse farmers. Implications for policy and extension efforts are highlighted.  相似文献   

13.
基于浙江省3县368户农户的调查数据,采用双重差分模型(DID)研究实施中央财政林业补贴政策对林农营林投入和收入的影响。结果表明:实施林业补贴政策可以显著增加农户的营林投入,但对农户的营林增收没有显著带动作用,这证明林业补贴能够有效刺激林农的营林积极性,但增收效果仍有待观察。因此,选取林业补贴对象应注重"普惠+特惠"制、林业补贴政策需长期稳定执行、政府部门应加强林业补贴政策的宣传力度。  相似文献   

14.
This article investigates the effects of wheat genetic diversity and land degradation on risk and agricultural productivity in less favored production environments of a developing agricultural economy. Drawing production data from a household survey conducted in the highlands of Ethiopia, we estimate a stochastic production function to evaluate the effects of variety richness, land degradation, and their interaction on the mean and the variance of wheat yield. Ethiopia is a center of diversity for durum wheat and farmers manage complex variety mixtures on multiple plots. Econometric evidence shows that variety richness increases farm productivity. Variety richness also reduces yield variability but only for high levels of genetic diversity. Simulations with estimated parameters illustrate how planting more diverse durum wheat varieties on multiple plots contribute to improving farmer's welfare.  相似文献   

15.
Farmers in low‐income rural economies often fail to switch to cash crops from staple production despite the positive income effects of commercialization expected by policy makers. The literature suggests that market failures prevent households from cash crop adoption but remains inconclusive regarding farmers' motives and the effects of commercialization. This article contributes to the debate by offering an original approach to the analysis of commercialization outcomes and farmers' decisions. It consists of applying a model with essential heterogeneity and a semiparametric estimation technique to analyzing harvest value returns to cash cropping. Using Malawian data, we show considerable heterogeneity in harvest value returns to cash cropping both within and between groups of farmers choosing different crop portfolios. Importantly, the results imply rational choices based on comparative advantage considerations of farming households: farmers self‐select into the activity where they expect higher gains and adopt cash crops when facing weaker market barriers.  相似文献   

16.
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   

17.
We predict the potential demand of smallholder farmers for genetically transformed varieties of a food crop, the cooking banana of the East African highlands. Farmer demand for planting material is derived in an agricultural household model that accounts for variety traits and missing markets. The demand for candidate host varieties is predicted using a Zero‐Inflated Poisson (ZIP) regression system. The fitted model is used to illustrate the sensitivity of farmer demand for improved planting material to (a) investments in research and development, represented by the effectiveness of gene insertion and expression, and (b) other public investments in education, extension, and market infrastructure that support diffusion. By comparing the characteristics of agricultural households we demonstrate that the choice of host variety can have social consequences, favoring one rural population compared with another. Clients for transgenic banana planting material are likely to be poorer, subsistence‐oriented farmers in areas greatly affected by biotic constraints. A model of this type might be useful in assessing the investments needed to support the systematic dissemination of improved planting material. The approach can be generalized to other crop biotechnologies for smallholder farming systems, particularly in developing economies.  相似文献   

18.
Malnourishment continues to remain a challenge in developing countries. As the undernourished are largely smallholder farmers, it is widely assumed that farm diversification and mixed crop‐livestock agricultural systems can help alleviate this problem. However, empirical evidence in this context is limited. Hence, we use a two‐year panel's data from Laos to examine whether farm production diversity as well as a mixed crop‐livestock farming system improves household dietary diversity among smallholder farmer. The results from the fixed effects regression indicate that although farm production diversity does lead to a higher dietary diversity, the effect diminishes with continued farm diversification. The counterfactual analysis from the endogenous switching regression reveals that mixed crop‐livestock farming systems do not necessarily enhance dietary diversity. However, we further find that purchasing food from the markets plays an important role in enhancing the dietary diversity of rural smallholder farmers.  相似文献   

19.
Variety change and genetic diversity are important means of combating crop losses from pests and diseases in modern agricultural systems. Since the Green Revolution, genetic diversity among wheat varieties released in India has increased but variety change on farms continues to be slow. In this article, we define and summarise indices of variety change and genetic diversity for the wheat varieties released and grown in Indian Punjab during the post‐Green Revolution period. We evaluate the effect of each index on technical efficiency with a Cobb‐Douglas yield model after testing for exogeneity. Findings support the hypothesis that slow variety change has offset the positive productivity effects of diversifying the genetic base in wheat breeding during the post‐Green Revolution period. Policies that speed the rate of variety change and contribute to a more equitable spatial distribution of modern varieties could support wheat productivity in the Punjab of India, reinforcing plant breeding successes.  相似文献   

20.
Peasant farmers in Sahelian West Africa adjust to rainfall uncertainties in the agricultural season by making decisions sequentially as a function of the evolving rainfall patterns. Understanding such flexibilities in farmer decision-making is central to technology introduction. This paper determines how sequential decision-making under weather uncertainty affects the adoption and farm-level effects of cereal technologies in Niger. The study also draws policy implications for a price floor to arrest the substantial fall in cereal prices in good rainfall years when farmers have more grains to sell. The methodology used is Discrete Stochastic Programming. This paper shows that the ability of peasant farmers to adapt cropping and resource-management strategies to the rainfall patterns is the basis for their survival in this high-risk environment. Model results show that by (a) carrying a portfolio mix of varieties of varying maturities, and (b) making sequential decisions based upon rainfall expectations, farmers can adapt to the production uncertainties. Breeding programs should therefore be diversified to develop not only early-maturing cultivars, but also improved intermediate and long-season varieties.  相似文献   

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