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1.
Smallholder vegetable production is expanding rapidly in Zimbabwe both for local sale in urban markets and for export. Pest management practices of 12 small-scale vegetable farmers in two areas of Zimbabwe were surveyed over a five-month period to gather information on crops, pests, diseases and crop protection methods. A range of serious pests and diseases affects non-indigenous vegetables such as Brassicas, tomatoes, onions and cucurbits. Although farmers use some cultural control methods and occasionally botanical pesticides, pest control is predominantly by the use of conventional synthetic pesticides. These are usually applied through lever operated knapsack sprayers although some less orthodox application methods are occasionally used. Results are variable and there are concerns about risks to sprayer operators, consumers and the environment (including natural enemies) due to shortcomings in protective clothing, large deviations from recommended doses and excessive run-off to the soil. Field trials were carried out to evaluate a modified sprayer lance which directs the spray upwards rather than downwards in an attempt to place more of the spray under the leaves where most of the arthropod pests are found. The ‘V lance’ as it is called improved the uniformity of spray coverage on the upper and lower leaf surfaces and is expected to improve efficacy of spraying and/or offer the opportunity to reduce doses or spray frequencies. Farmers who tested the device reported good results and gave constructive feedback for future improvements. The smallholder vegetable sector requires support in the form of improved access to existing pest management information (in an appropriate form) and focused research targeted at the knowledge gaps which currently impede implementation of sustainable IPM.  相似文献   

2.
The objective of this paper is to explore the extent to which systems approaches to innovation are reflected in the crop protection literature and how such approaches are used. A systematic literature review is conducted to study the relation between crop protection and systems approaches to innovation in 107 publications. The analysis of the crop protection literature demonstrates that only a small fraction is systems-oriented as compared to the bulk of publications with a technology-oriented approach. The analysis of agricultural innovations systems literature shows that, although crop protection is addressed, the potential of this systems approach remains largely unexplored for crop protection innovation. A large share of the publications included in this review focus on cropping or farming ‘systems’ while ‘innovation’ often equals the development, transfer, adoption and diffusion of crop protection technologies at farm level. There is relatively little attention for the institutional and political dimensions of crop protection and the interactions between farm, regional and national levels in crop protection systems. The traditional division of roles and responsibilities of researchers as innovators, extension personnel as disseminators, and farmers as end-users, is challenged only to a limited extent. The majority of publications discusses ways to optimise existing features of crop protection systems, without exploring more structural transformations that may be required to enhance the resilience of crop protection systems.  相似文献   

3.
Ugandan farmers were interviewed in order to investigate their knowledge, perceptions and ability to manage pests in agroforestry generally and on Alnus species particularly. Farmers’ ability to recognise pest problems on Alnus species was significantly influenced by their length of experience in cultivating the species, but not their age, sex or formal education. Most farmers (77%) were aware of pest problems on Alnus species. However, identification of pest problems was based largely on damage type rather than causal agents. Whereas farmers had good knowledge of vertebrate pests of Alnus, insects and diseases that infest the tree species were unknown to most farmers. Apis mellifera damage on Alnus was the most frequently described damage, but its cause was either unknown or misdiagnosed. Most farmers did not control insect and disease infestations on Alnus because they did not know the causal agents and/or appropriate control measures. Farmers were generally more knowledgeable on insect and disease infestations on crops than on multipurpose tree species (MPTS) and most of them (98%) perceived that crops suffer more damage from such pests than do MPTS. However, farmers’ ability to manage insect pests and diseases seemed weak on both crops and MPTS. Most farmers suggested the use of pesticides to combat pests, but they mentioned only one insecticide, permethrin and one fungicide, mancozeb. More alarming were the suggestions by a few farmers on the use of mancozeb against aphids, and permethrin to combat crop wilt and dieback. Farmers need to be educated about diagnosis, basic ecology and management strategies for both crop and tree pests to ensure sustainable pest control in agroforestry.  相似文献   

4.
Widespread use of highly toxic pesticides primarily for agricultural purpose has generated increasing concerns about the negative impact of pesticides on human health and the environment. Integrated pest management (IPM) usually seeks to minimize the use of pesticides and can be utilized to solve pest problems while minimizing risks to people and the environment. A total of 220 vegetable farmers in Nakhon Ratchasima Province of Thailand was interviewed with the objective of investigating the factors determining their adoption or non-adoption of IPM practices. The findings demonstrated that farmers had different uncompromising reasons for determining the use of IPM for their insect pest management. Higher costs of insecticides (91%), adverse effects of insecticides on human health and the environment (80%), and a greater risk of insect pests developing resistance to insecticides (28%) were the primary reasons for the adoption of IPM by vegetable growers in the study area. The reasons for the rejection of IPM practice were unsuitability of IPM for a large farm (52%), implementation difficulties (80%) and a greater belief in synthetic insecticides and their efficacy for target pest control (39%). A comparison between the IPM and the non-IPM farmers showed a significant difference (P < 0.01) in farmers' knowledge of pest management, which influenced IPM adoption or non-adoption. The IPM farmers had greater knowledge about identifying natural enemies and their beneficial role in controlling insect pests, about plant extracts and their efficacy in controlling insect pests and about sticky traps and their efficacy in monitoring natural enemies and controlling insect pests. For example, 24% of IPM farmers had knowledge of natural enemies whereas it was only 4% for the non-IPM farmers. A logistic regression model was fitted which showed that lower cost of pest management, better knowledge on IPM after training and availability of extension services were the factors which influenced farmers' adoption of IPM practice. The non-IPM farmers rejected adoption of IPM due to the common belief that natural enemies would not be effective in controlling insect pests and yields of vegetables would not be increased by practicing IPM.  相似文献   

5.
Summary

Small scale diversified systems which rely mostly on local resources and complex crop arrangements, are reasonably productive and stable, exhibiting a high return per unit of labor and energy. In many ways complex polycultures and agroforestry systems used by small tropical farmers mimic the structure and function of natural communities therefore acquiring many features typical of such communities, such as tight nutrient cycling, resistance to pest invasion, vertical structure, and high levels of biodiversity.

An agroecological approach to improve tropical small farming systems must ensure that promoted systems and technologies are suited to the specific environmental and socio-economic conditions of small farmers, without increasing risk or dependence on external inputs. Rather, agroecological development projects should incorporate elements of traditional agricultural knowledge and modern agricultural science, featuring resource-conserving yet highly productive systems such as polycultures, agroforestry, and the integration of crops and livestock.

It is ecologically futile to promote mechanized monocultures in areas of overwhelming biotic intricacy where pests flourish year-round and nutrient leaching is a major constraint. Here, it pays to imitate natural cycles rather than struggle to impose simplistic ecosystems that are not inherently complex. For this reason, many researchers think that successional ecosystems can be particularly appropriate templates for the design of sustainable tropical agroecosystems.  相似文献   

6.
Crop pests are a major constraint to the intensification of agricultural production in the tropics, with novel issues related to global change (climate, land use, biological invasions, etc.), food security and preservation of natural resources and biodiversity. A research, extension and education network called DIVECOSYS (Diversity of cropping systems and ecologically-based pest management in West Africa) was launched in 2010 to synergize applied research actions in response to growing concerns on the vulnerability of agricultural systems to pest management in West Africa. This scientific network brings together research and academic institutions, with expertise spanning a multidisciplinary perspective from biology and ecology to remote sensing, agronomy and integrated pest management. Its main scientific objective is to explore the potential of biodiversity and ecological processes such as pest regulation, enabling novel ecologically-based models for productive systems, reduction of pesticide use, and adaptation or resilience of farming systems in the face of environmental disruptions. From Northern Senegal to Southern Benin, the research group explores a wide range of ecoregions and socio-ecological contexts, including stakeholders and their objectives, land use and agricultural practices, and management of biodiversity for enhancing biological control. Main challenges to be turned into opportunities include (i) encouraging collaborations amongst researchers from different scientific fields, (ii) fostering interactive research and synergies among research institutions and among countries, and (iii) developing an ecological engineering approach for the design of sustainable agricultural systems for smallholder farmers.  相似文献   

7.
Insect pests are a key constraint to effective utilization of cereal crops in sub-Saharan Africa (SSA), with damage caused by these pests in the stores of particular concern. Although a number of approaches have been advanced for control of storage pests of maize, uptake remains a challenge, with effectiveness of some approaches being questionable. We conducted a survey in western Kenya among 330 respondents using face to face interviews and focus group discussions to evaluate farmers' practices, knowledge and perceptions of storage pests of maize, and their current practices in managing such pests as a basis for development of efficient integrated pest management (IPM) approaches for the pests. Majority of the respondents stored maize in traditional granaries, with less than 10% of them using modern improved facilities, mainly due to inability to afford these. Majority of the respondents also cited attack of their stored grains by a number of insect pests, causing about 40% grain losses. The larger grain borer, Prostephanus truncatus (Horn) (Coleoptera: Bostrichidae), sawtoothed grain beetle, Oryzaephilus surinamensis (L) (Coleoptera: Silvanidae), and maize weevil, Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae), were perceived as the most common and damaging pests. Farmers' perceptions of pests were positively and significantly influenced by level of education and farming experience, indicating that education and experience build farmers' understanding of storage pests. Storing maize in unshelled form seemed to result in less pest attack, although majority of the respondents stored their maize in shelled form. Moreover, local maize varieties were perceived to be resistant to pests. The farmers applied various control methods, with sun-drying being the most popular practice. Usage of pesticides was minimal, mainly due to high costs, lack of information, and unavailability of appropriate and effective products. There were also other cultural methods applied, such as use of smoke and insecticidal plants. The respondents decried lack of training and extension services on storage pests and their management, underscoring the need to develop extension services. The underlying mechanisms of the perceived pest resistance in local varieties of maize and cultural pest management methods need to be established for exploitation in development of effective IPM approaches. There is also need to address the challenges hindering uptake of modern storage and control approaches.  相似文献   

8.
Grain legumes play an important role in community livelihood and in the national economy in Kenya. Unfortunately, in many African countries, production doesn't satisfy the demand in grains due to various constrains. Understanding farmers practices and behavior in the management of grain legume pests is a crucial step in the development of sustainable management strategies. A total of 216 farmers were surveyed in eight districts of eastern Kenya to evaluate farmers' knowledge and perceptions of grain legume pests; to examine current pest management practices, and to identify other production constraints. Grain legumes are grown by a wide age-group of farmers, with both genders equally represented. Chemical control remains the main pest management strategy, and, to ensure pesticide effectiveness, farmers also use increased application rates, chemical alternation, frequent application and mixtures of chemicals. While farmers used other control measures, they showed only limited interest in biological control. The majority of the farmers had experience in grain legume farming and were able to identify the major pests, which were the legume flower thrips Megalurothrips sjostedti Trybom, the cowpea aphid Aphis craccivora Koch and the legume pod borer Maruca vitrata Fabricius. Our survey revealed that education and proximity to extension services contributed significantly to farmers' knowledge of grain legume pests, suggesting the need to provide continuous training and capacity building on integrated pest management in grain legume farming. The study also suggests integration of other pest management strategies such as the use of early maturing varieties, biopesticides and biofertilizer to reduce the use of chemical for sustainable pest management.  相似文献   

9.
《Journal of Crop Improvement》2013,27(1-2):271-305
SUMMARY

Cropping systems have been central to managing associated pests for centuries. This treatment focuses on the history, concepts, and the integration of available Integrated Pest Management (IPM) tools/strategies into cropping systems. Pest assessments/diagnoses, IPM-decision-making aids, and examples of pest management in selected crops/cropping systems (wheat, soybean, corn, cotton, potato, and strawberry) as well as emerging opportunities and challenges are discussed. The evolving philosophy of IPM and the recently renewed emphasis on ecologically based pest management address the fact that significant levels of predation and/or parasitism are desirable insofar as they promote diversity and sustainability of agroecosystems. Thus, cropping systems are beginning to focus on soil and crop health as well as specific IPM and production goals. Although extensive efforts have been directed toward modeling the many interactions between crops, associated pests and the environment, the general implementation of a systems approach to integrated crop and pest management remains to be accomplished.  相似文献   

10.
While research on biological control of crop pests is quite popular, it seldom targets motivations of farmers for adopting this practice. A survey of 283 rice farmers was conducted in Mazandaran province of northern Iran to study farmers' motivations for biological control adoption as an alternative control method of Asiatic rice borer [Chilo suppressalis (Walker)] and explain potential differences in motivations among different groups of farmers. Face to face interviews were used to address farmers' motivations based on a list of motivation statements found in previous studies and modified by extension officers and farmers who had adopted biological control in the study area. Factor analysis of a motivation list with 15 items revealed four main groups of factors explaining the adoption of biological control by rice farmers; these were ‘health maintenance’, ‘economic benefit’, ‘social acceptance’, and ‘environmental protection’. Men gave high scores to motivations related to ‘economic benefit’ and ‘social acceptance’, whereas women preferred mostly motivations related to ‘health maintenance’. Well-educated farmers (e.g., some college education) preferred motivations for ‘health maintenance’ more than farmers with lower education or no education at all. Participation in extension programs was associated with preference of non-economic motivations of biological control adoption, while membership in local associations (such as rural cooperatives or producers' groups) encouraged motivations related to ‘social acceptance’. Farmers who used family labor force in their fields or farmers who perceived pesticides as harmful substances showed strong motivations primarily for ‘health maintenance’ along with ‘environmental protection’. Small area of land under cultivation and low annual farm income were strongly linked with motivations for ‘economic benefit’. Besides economic motivations, policies for the promotion of biological control adoption should embrace a wide set of farmers' motivations when developing new and properly tailored extension programs.  相似文献   

11.
Selecting appropriate strategies for pest control has become an issue of major concern, but research on decision making regarding this issue is limited. An analytic hierarchy process (AHP) approach for selecting strategies for the management of rice stem borer [Chilo suppressalis (Walker)] in paddy fields of Sari county of Mazandaran province in Iran was developed. Agricultural faculty members, experts of a local plant protection unit, local extension agents, and elite farmers in the study area participated in the project to determine the suitability of four common pest control methods (i.e., chemical control, cultural control, biological control, pheromone trapping) for rice stem borer management, based on 10 main criteria and 32 sub-criteria identified through pertinent literature and focus group discussions. All the examined alternatives of pest control were preferred to some extent for rice stem borer management. Control effectiveness, relative advantages, social usefulness, and technical support were the most important criteria for assessing strategies for rice stem borer management, followed by observability, ease of use, trialability, farmer's self-efficacy, compatibility, and farm characteristics. Overall, chemical control ranked first, being superior to the other three methods with respect to six main criteria of the model (relative advantages, trialability, observability, farmer's self-efficacy, farm characteristics, and control effectiveness). Biological control ranked second at the overall level, being superior to cultural control and pheromone trapping in the three remaining main criteria (i.e., technical support, compatibility, and social usefulness). Pheromone trapping ranked first only with respect to ease of use criteria. The proposed model constitutes a flexible tool for decision making in pest control with high applicability among policy makers in the government and local agricultural office and extension agents; it could greatly assist extension programs to effectively select strategies for rice stem borer management or similar pest problems in various agricultural sites.  相似文献   

12.
S. Finch  R. H. Collier 《Crop Protection》2000,19(8-10):817-824
Improvements in (1) insecticide application, (2) supervised control, and (3) pest forecasting systems have each helped to reduce considerably the amounts of insecticides required to control fly, caterpillar and aphid infestations in vegetable crops in northern Europe. By growing plants that are partially resistant to certain major pests, it is now possible to apply even less insecticide than the dose recommended for the crop. In crops where only small amounts of insecticides are applied, natural predators should prevent large increases in pest insect populations and natural parasitoids should reduce the numbers of pest insects entering subsequent generations. The possible impact of introducing transgenic plants and the use of physical (crop covers), cultural (crop rotation, undersowing) and microbial (e.g. fungi, bacteria and nematodes) methods of control are also discussed. The withdrawal of certain insecticides, as a result of environmental and commercial pressures, means that some crops may soon be without appropriate insecticides for controlling one or more of the major pest species. Whether such systems will be sustainable, remains to be seen.  相似文献   

13.
Despite research efforts spanning many decades, invertebrate pest control in arable farming systems is still heavily reliant on broad-spectrum pesticides. Yet industry wants to implement Integrated Pest Management (IPM) principles. We suspect that the lack of implementation to date reflects the unpredictable nature of outbreaks of pests and unpredictable profit margins, creating an environment where growers prefer to follow a cautious chemical-based approach. Using southern Australia as a case study, we argue for a new approach where the concept of rigid management strategies is abandoned in favor of landscape changes, host plant resistance, ecological indicators, reliable predictors and emergency intervention strategies. This approach needs to be based on developing more stable crop environments that can limit fundamental niches available for exploitation by sporadic pest populations, and increasing crop resilience to resident herbivores. Fall-back strategies, including broad-spectrum chemical control, may still be required to protect productivity at times when outbreaks of pest populations take place. These are likely to be unavoidable, particularly given emerging climate challenges.  相似文献   

14.
Smallholder farmers dominate agriculture in Nepal. These farmers have poor knowledge about agriculture and lack of support for soil management and integrated plant-nutrient systems. Focusing on the importance and need for soil-fertility management, a soil-testing mobile van program has recently been introduced in Nepal by Soil Management Directorate, Hariharbhawan. With the introduction of the mobile lab, famers can get their soil tested for nutrient deficiencies and fertilizer requirements at their doorsteps. Using mobile lab, spatial distributions of chemical properties, including pH, organic matter (OM), total nitrogen (N), available phosphorus (as P2O5), and available potassium (as K2O) were examined in soil samples taken from the 0 to 15 cm depth from selected agricultural fields in eight different districts in the mid-hills and Terai regions of Nepal. Tests conducted on 1,479 soil samples in the soil-testing mobile van revealed the following: the mean soil OM ranged from 0.01 to 1.77%; total N content ranged from 0.01 to 0.08%; mean available P2O5 ranged from 16.47 to 197.82 kg ha?1; and mean available K2O ranged from 84.3 to 422.57 kg ha?1. For each crop to be grown, farmers were provided with individual soil health reports and fertilizer recommendations (rate, amount, and type). This program not only allows scientists and farmers to work closely and share information but also serves as a model for the nation to successfully transfer technology for improving soil health and sustainability.  相似文献   

15.
The diamondback moth (DBM), Plutella xylostella (L.), remains a major pest of brassica crops worldwide. DBM has been estimated globally to cost US$ 1 billion in direct losses and control costs. Chemical control of this pest remains difficult due to the rapid development of resistance to insecticides and to their effect on natural enemies. These problems are especially severe in South Asia and Africa where lack of knowledge, limited access to newer and safer insecticides, and a favourable climate result in DBM remaining a serious year-round pest which substantially increases the cost and uncertainty of crop production. Despite these problems, application of synthetic insecticides remains overwhelmingly the most common control strategy. Biologically-based efforts to control DBM in Africa and Asia have focused strongly on parasitoid introductions. However, despite the identification and deployment of promising parasitoids in many regions, these efforts have had limited impact, often because farmers continue early-season spraying of broad-spectrum insecticides that are lethal to parasitoids and thus exacerbate DBM outbreaks. A significant driver for this pattern of insecticide use is the presence of aphids and other pests whose appearance initiates inappropriate spraying. Despite often extensive training of producers in farmer field schools, many growers seem loath to discard calendar or prophylactic spraying of insecticides. The introduction of an IPM technology that could replace the use of broad-spectrum insecticides for DBM and other key Lepidoptera is crucial if the benefits of parasitoid introduction are to be fully realised. The deployment of DBM-resistant brassicas expressing proteins from Bacillus thuringiensis could help to break this cycle of insecticide misuse and crop loss, but their deployment should be part of an integrated pest management (IPM) package, which recognises the constraints of farmers while addressing the requirement to control other Lepidoptera, aphids and other secondary pests.  相似文献   

16.
The use of improved high yielding crop varieties is an important avenue for reducing hunger and food insecurity in developing countries. Using cross-sectional data obtained from a survey conducted during 2013 crop season, we performed a probit model(plot-level analysis) to determine the probability of adopting new improved rice varieties(NIRVs) by smallholder farmers particularly from two main agro-ecological regions(hills and tropical plain terai regions) of Central Nepal. The results revealed that education, extension services and seed access play significant roles in adoption decisions.Additionally, farm and field characteristic variables such as farm size, endowment of favorable land type(e.g. lowlands), and animal power(e.g. oxen) are the key factors influencing the probability of adopting NIRVs. The results showed that technology specific variables(e.g. yield potential and acceptability) are significant for explaining adoption behavior, implying that it is important to take farmers' preferences to varietal characteristics into consideration in the design of a research and development program. Given the significant role played by extension and access related variables, increased emphasis on information dissemination, field demonstration, and farmers' participatory research and training programs to popularize new rice varieties and enhance their adoption rate are required. This also suggests that policy intervention should be made on improving the educational status of farming households, and developing programs on varietal package of rice seed which offer farmers a variety of choices among the appropriate pools of germplasm. Such programs ultimately help farmers develop more profit-oriented behavior which are necessary to enhance adoption rate, production and food security in the long run.  相似文献   

17.
《Crop Protection》1988,7(3):161-167
Heliothis armigera is the most important cotton pest in Tanzania, and also attacks several food crops grown in a relay-intercropping system practised by small-scale farmers in Western Tanzania. The level and timing of H. armigera infestations were studied on its main alternative host plants: maize, sorghum, cotton, chickpea, tomato and the wild host Cleome sp. The attractive stages of these hosts overlap throughout the year. The expansion of chickpea and the introduction of tomato production has enabled the pest to survive better during the dry season, thus bridging an otherwise unfavourable period. The recent increased popularity of maize as a food crop, coupled with the introduction of compact and semi-compact panicle sorghum varieties instead of the traditional open-panicle sorghum cultivars, together with the expansion of cotton acreage, has increased the severity of attacks on sorghum and cotton. Effective control of the pest on early-sown sorghum offers the possibility of reducing numbers that subsequently attack early-season cotton. Although early-sown maize and sorghum can generate heavy populations which attack cotton in February–March, later crops flowering in March–April can usefully divert the pest away from cotton. Some of the alternative host plants, notably the weed, Cleome sp., are important sources of pesticide-susceptible strains of the pest population, which may decrease the likelihood of pesticide-resistant strains developing.  相似文献   

18.
The International Potato Center (CIP) and collaborating institutions implemented an intensive research programme over a period of 25–30 years on the use of botanical seed of potato as an alternative way of growing a potato crop. The use of botanical or ‘true’ potato seed (TPS) had many advantages over the use of seed tubers. Potentially, the use of TPS was especially attractive for small-scale farmers in developing countries. The difference of using TPS as compared to using seed tubers meant in many respects the development of a new crop–commodity chain, requiring research on breeding, seed production, agronomy and marketing aspects. This research made it possible to produce potatoes from TPS at commercial scale: it removed a number of important constraints in the uniformity and earliness of the TPS varieties and in seed physiology. Experimentation and adoption by farmers in a wide range of countries showed that the technological advantages of using TPS were only translating in economical benefits as compared to tuber seed when the last one was costly or not available. Since the economic performance of seed tubers is likely to continue to fluctuate, TPS remains an interesting alternative. Study of the use of TPS in various countries could contribute to better understanding of factors that promote or inhibit crop technology innovation. The article gives an overview of the various areas of TPS research in CIP and presents information on the application of TPS technology in several developing countries.  相似文献   

19.
Knowledge-based systems for crop protection: theory and practice   总被引:1,自引:0,他引:1  
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20.
A push–pull strategy for controlling Eldana saccharina Walker is being promoted as part of an area-wide integrated pest management (AW-IPM) programme in the South African sugar industry. Understanding farmers' perceptions of pests and pest management can improve rates of adoption of pest management strategies, in particular for knowledge-intensive practices such as AW-IPM. Fifty-three large-scale sugarcane farmers were interviewed using a semi-structured questionnaire. Respondents recognised the threat which E. saccharina posed, and 83% had heard of push–pull and IPM. Ecozone delineations played a more important role in adoption decisions than demographic and general enterprise factors such as farmer age, experience and land tenure, supporting the suggestion that experiential learning activities with small, local groups of farmers are suitable for introducing new pest management strategies. Notwithstanding good basic knowledge of E. saccharina, push–pull and IPM which farmers demonstrated, there is still a need for more detailed and practical knowledge on the implementation of push–pull at farm level. This knowledge should be made available to farmers in a hands-on manner with an emphasis on locally-oriented field days and model farms. Eldana saccharina may not be a priority for all farmers in the region where surveys were conducted. However, farmers should not be allowed to become complacent about this pest, as its range is increasing. These results will be used to formulate future push–pull and AW-IPM dissemination activities amongst large-scale sugarcane farmers in South Africa.  相似文献   

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