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1.
Decision-makers in the protected crop environment face similar pest-management decisions, in economic terms, to growers of field crops or grain store managers. As a result, the principles of economic thresholds, cost: benefit analyses and risk minimisation apply equally to each of these systems. Growers are faced with several general classes of pest-control decisions: the general control strategy to adopt, and then tactical questions such as when to start control and when to stop or change control practices. However, there are a number of aspects of protected crops which require a somewhat different view of the problem. Several economic models for these questions are examined. The high density of protected crops means that a great deal is at risk at any one time. The protected environment reduces uncertainty about losses, but by optimising temperatures and humidities it increases the probability of loss. The feeling of being able to “control” the environment may extend to pests as well, increasing the use of standard pesticide or biocontrol programmes, rather than responsive pest management based on thresholds. The relatively small scale of protected crops, their accessibility for inspection and the high level of management skills involved in their production improve prospects for monitoring and predicting crop levels, insects and diseases, thus reducing uncertainty. However, the high probability of loss may reduce the value of gathering information, and encourage growers to rely on standard prophylactic procedures which allow them to devote management effort to more productive activities, such as marketing. The balance may be shifted towards more information-based decisions in the future to try to avoid excessive pesticide use because of more stringent regulations on pesticide residues and changing market demand for more organic produce. This may affect disease control in particular, where prophylactic biological control is not an option. At the policy level, feedback on environmental impacts to consumers and policy-makers is poor and decisions with expensive implications for the economy and for environmental quality may not be made in an optimal manner.  相似文献   

2.

Part 1 of the paper showed that the integration of a lucerne/ cotton interplant system with supplementary food sprays retained and increased populations of predatory insects in the cotton crop. The strategic use of biopesticides (Bacillus thuringiensis (Bt), nuclear polyhedrosis virus (NPV)) reduced the use of synthetic insecticides by 50% without sacrificing cotton yield and profitability. In economic terms, the average gross margin for the IPM plot was A$3255 compared with A$3020 and A$3218 for the plots treated with (1) conventional insecticides on transgenic (Ingard®) cotton and (2) conventional insecticides on non-transgenic cotton. The use of transgenic cotton affected a 25% saving on synthetic insecticide usage. The results clearly indicate that a refined IPM approach could have a distinctive advantages in terms of economic and environmental impacts on cotton production. The success of such an approach lies in a strict adherence to its methodology.  相似文献   

3.
Chellemi DO 《Phytopathology》2002,92(12):1367-1372
ABSTRACT Nonchemical methods including host resistance, organic amendments, crop rotation, soil solarization, and cultural practices have been used to control soilborne pests in fresh market vegetable production systems. Their suitability as alternatives to methyl bromide will depend on the approach to pest management used by the grower. Traditionally, methyl bromide is used in production systems that rely on the single application of a broad-spectrum biocide to disinfest soils prior to planting. Non-chemical methods are not suitable for a single tactic approach to pest management because they do not provide the same broad spectrum of activity or consistency as fumigation with methyl bromide. Nonchemical methods are compatible with an integrated pest management (IPM) approach, where multiple tactics are used to maintain damage from pests below an economic threshold while minimizing the impact to beneficial organisms. However, adoption of IPM is hindered by the paucity of economically feasible sampling programs and thresholds for soilborne pests and by a reluctance of growers to commit additional resources to the collection and management of biological information. A novel approach to the management of soilborne pests is to design the crop production system to avoid pest outbreaks. Using this "proactive" approach, a tomato production system was developed using strip-tillage into existing bahia-grass pasture. By minimizing inputs and disruption to the pasture, growers were able to reap the rotational benefits of bahiagrass without cultivating the rotational crop. While minimizing the need for interventive procedures, a proactive approach is difficult to integrate into existing crop production systems and will require several years of testing and validation.  相似文献   

4.
BACKGROUND: Glyphosate‐resistant (GR) crops have changed the way growers manage weeds and implement control strategies. Since the introduction of GR crops, growers in many instances have relied on glyphosate almost exclusively to control a broad spectrum of weeds. This overreliance on glyphosate has resulted in the evolution of glyphosate resistance in some weed species. Growers and scientists are concerned about the sustainability of GR crops and glyphosate. When a grower is making decisions about weed control strategies, economic costs and benefits of the program are primary criteria for selection and implementation. Studies across six states were initiated in 2006 to compare the economics of using a weed resistance best management practice (BMP) system with a grower's standard production system. RESULTS: Resistance BMP systems recommended by university scientists were more costly but provided similar yields and economic returns. Rotation of GR crops resulted in a higher net return (maize and soybean) compared with continuous GR crop (cotton or soybean) or rotating a GR crop with a non‐GR crop (maize). CONCLUSION: Growers can implement weed resistance BMP systems with the confidence that their net returns will be equivalent in the short run, and, in the long term, resistance BMP systems will prevent or delay the evolution of GR weeds in their fields, resulting in substantial savings. Copyright © 2011 Society of Chemical Industry  相似文献   

5.
A method was developed to evaluate crop disease predictive models for their economic and environmental benefits. Benefits were quantified as the value of a prediction measured by costs saved and fungicide dose saved. The value of prediction was defined as the net gain made by using predictions, measured as the difference between a scenario where predictions are available and used and a scenario without prediction. Comparable 'with' and 'without' scenarios were created with the use of risk levels. These risk levels were derived from a probability distribution fitted to observed disease severities. These distributions were used to calculate the probability that a certain disease induced economic loss was incurred. The method was exemplified by using it to evaluate a model developed for Mycosphaerella graminicola risk prediction. Based on the value of prediction, the tested model may have economic and environmental benefits to growers if used to guide treatment decisions on resistant cultivars. It is shown that the value of prediction measured by fungicide dose saved and costs saved is constant with the risk level. The model could also be used to evaluate similar crop disease predictive models.  相似文献   

6.
BACKGROUND: Growers have enthusiastically embraced crops genetically modified to express Bacillus thuringiensis (Bt) proteins for insect control because they provide excellent protection from key damaging insect pests around the world. Bt crops also offer superior environmental and health benefits while increasing grower income. However, insect resistance development is an important concern for all stakeholders, including growers, technology providers and seed companies that develop these genetically modified crops. Given the marked benefits associated with Bt crops, insect resistance management (IRM) must be a consideration when cultivating these crops. RESULTS: The technical data and practical experience accumulated with Bt crops in many global regions can inform different aspects of resistance management leading to robust, science‐based IRM plans. A range of elements should be considered in assembling any IRM strategy, including: pest biology/ecology, product deployment patterns, local cropping systems, insect susceptibility monitoring, stakeholder/grower communications, and a remedial action plan should resistance develop. Each of these elements is described in more detail, with specific examples of how these elements can be combined and tailored to the local/regional environments and grower practices. CONCLUSION: IRM plans need to be suitable for the given production situation. What works for large monoculture production systems in North America is unlikely to be appropriate for the small, more diverse agriculture of southeast Asia or Africa. Though it is clear that Bt crops impart considerable value to growers, it is also clear that it is in the best interest of all stakeholders to preserve Bt proteins for the long‐term benefits they provide. Copyright © 2009 Society of Chemical Industry  相似文献   

7.
This contribution to Zadoks’ liber amicorum reviews the developments in quantitative epidemiology during the last decades. It elucidates the progress in this field and shows how empirical crop protection with many phenomenological aspects transformed into a science-based (inter) discipline.The availability of experimental tools and the rapid development and introduction of computers enabled the application of systems approaches which stimulated a revolution in thinking and caused a considerable improvement of strategic and tactical decision making in crop protection. Zadoks played a crucial role in that development.  相似文献   

8.
The diversity of competing interests in North America provides a remarkable series of divergent messages to growers. Depending on what crop they produce or how they farm, they may be heroes or villains, loyal or unpatriotic, or stewards or ravagers of the environment. Even relatively minor changes in farming practices can result in significant public or political response. Considering that growers may risk 100% of their crop yield on a potential savings of 10% (or less) for investment in pesticides, it is not surprising that growers are slow to adopt IPM programs. Well-intentioned appeals to eliminate pesticides, or save the environment at all costs, are usually not effective. Likewise, a high failure rate can be expected from attempts to legislate IPM, implement programs that focus on only part of a pest complex, or adoption strategies that do not include on-farm testing and extensive educational efforts. However, some strategies have proven effective. Growers who have experienced loss of pesticides due to resistance are receptive to management programs which avoid or delay resistance. Many programs have been adopted piecemeal, starting with sampling programs followed by treatment thresholds and modified pesticide use. One of the most successful approaches has been an economic comparison of grower standard and IPM programs using partial budgets. Increased net profits provide powerful incentives for program adoption.  相似文献   

9.
Seed potato degeneration, the reduction in yield or quality caused by an accumulation of pathogens and pests in planting material due to successive cycles of vegetative propagation, has been a long‐standing production challenge for potato growers around the world. In developed countries this problem has been overcome by general access to and frequent use of seed, produced by specialized growers, that has been certified to have pathogen and pest incidence below established thresholds, often referred to as certified seed. The success of certified seed in developed countries has concentrated the research and development agenda on the establishment of similar systems in developing countries. Despite these efforts, certified seed has had little penetration into the informal seed systems currently in place in most developing countries. Small‐scale farmers in these countries continue to plant seed tubers acquired through the informal seed system, i.e. produced on‐farm or acquired from neighbours or local markets. Informal seed tubers frequently have poor health status, leading to significant reductions in yield and/or market value. This review emphasizes the need to refocus management efforts in developing countries on improving the health status of seed tubers in the informal system by integrating disease resistance and on‐farm management tools with strategic seed replacement. This ‘integrated seed health strategy’ can also prolong the good health status of plants derived from certified seed, which would otherwise be diminished due to potential rapid infection from neighbouring fields. Knowledge gaps, development challenges and impacts of this integrated seed health strategy are discussed.  相似文献   

10.
草莓灰霉病研究进展   总被引：12，自引：0，他引：12  
张国珍  钟珊 《植物保护》2018,44(2):1-10
草莓灰霉病是草莓上最重要的病害之一,在温室和露地栽培中均普遍发生,草莓生长期和采后果实均可被侵染,造成严重的经济损失。本文结合作者近年来对草莓灰霉病的有关研究,就草莓灰霉病的症状和危害,病原菌的种类,分生孢子萌发的最适温湿度,病原菌的抗药性,影响草莓灰霉病发生的因素包括品种抗感性、不同器官的带菌量和空气中的孢子量及环境条件,草莓灰霉病综合防治等方面的国内外研究进展进行综述,以期为从事相关研究的科研人员和生产技术人员提供参考与帮助。  相似文献   

11.
This contribution to Zadoks’ liber amicorum reviews the developments in quantitative epidemiology during the last decades. It elucidates the progress in this field and shows how empirical crop protection with many phenomenological aspects transformed into a science-based (inter) discipline. The availability of experimental tools and the rapid development and introduction of computers enabled the application of systems approaches which stimulated a revolution in thinking and caused a considerable improvement of strategic and tactical decision making in crop protection. Zadoks played a crucial role in that development.  相似文献   

12.
The aim of integrated farming systems research is to develop sustainable farming systems from an economic, technical and environmental point of view. Strategies for crop rotation, crop protection and fertilization are briefly discussed in relation to potato production. The effects of different levels of fertilization on the incidence of some pests and diseases of potatoes are discussed in more detail, based on a literature study. Some results of potato production on the three farms for integrated arable farming in the Netherlands are also presented.  相似文献   

13.
BACKGROUND: A survey of 400 growers of maize, soybeans and cotton was made in the United States to determine perceptions, experiences and management practices with glyphosate-resistant weeds. The survey included growers in the north (corn belt) and south (cotton belt) of the USA in spring 2006. RESULTS: Interestingly, 24 and 39% of northern and southern growers, respectively, assumed they had glyphosate weed resistance on their farm. Of the 200 southern growers interviewed, 67% had planted continuous glyphosate-resistant (GR) crops for a period of 3-5 years. According to the survey respondents, the key method for managing glyphosate-resistant weeds was to rotate to other herbicides. CONCLUSION: Growers do value GR crop technology but are adopting measures to manage resistance only as needed.  相似文献   

14.
Recent research has suggested that a high proportion of farms can dramatically reduce pesticide applications without reducing crop yields or farm profits. Yet this research has made estimation choices that may systematically bias downwards estimates of the productivity and profitability of pesticides. Fifty years of agricultural economics research provides lessons about how to avoid pitfalls in estimating pesticide productivity. Carefully executed econometric studies have found evidence of overuse, underuse, and near‐optimal use of pesticides in different cropping systems. There are now standard methods to test and correct for sources of biases (either upward or downward) in estimates of pesticide productivity. Ignoring these lessons and methods can seriously bias estimates of the potential for reducing pesticide use at little or no economic cost. © 2018 Society of Chemical Industry  相似文献   

15.
Summary Density:yield loss models rely on fixed coefficients, parameterized from a particular site and season to predict the impact of weeds on crop yields. However, the empiricism of this approach and failure to incorporate environmental effects, has major biological and economic implications. In this study, seasonal variability in wheat yield loss and associated economic costs from Avena spp. were quantitated. A competition experiment at Wagga Wagga, NSW, showed large seasonal differences in wheat yield loss from densities of Avena spp. across 2 years. Gross margins, simulated over a 51-year period, decreased as Avena spp. density increased and were more variable at low crop densities and higher weed densities. For example, at a density of 200 Avena spp. plants m−2, coefficient of variation in crop gross margin ( CV ) was $AUS 47 ha−1 for a crop density of 200 wheat plants m−2 compared with a CV of $AUS 75 ha−1 for a crop density of 50 wheat plants m−2. The value of yield loss predictions will be vastly improved by making parameter values in yield loss models a function of seasonal factors such as rainfall.  相似文献   

16.
Globalization causes plant production systems to be increasingly threatened by invasive pests and pathogens. Much research is devoted to support management of these risks. Yet, the role of growers' perceptions and behavior in risk management has remained insufficiently analyzed. This article aims to fill this gap by addressing risk management of invasive pathogens from a sociopsychological perspective. An analytical framework based on the Theory of Planned Behavior was used to explain growers' decisions on voluntary risk management measures. Survey information from 303 Dutch horticultural growers was statistically analyzed, including regression and cluster analysis. It appeared that growers were generally willing to apply risk management measures, and that poor risk management was mainly due to perceived barriers, such as high costs and doubts regarding efficacy of management measures. The management measures applied varied considerably among growers, depending on production sector and farm-specific circumstances. Growers' risk perception was found to play a role in their risk management, although the causal relation remained unclear. These results underscore the need to apply a holistic perspective to farm level management of invasive pathogen risk, considering the entire package of management measures and accounting for sector- and farm-specific circumstances. Moreover, they demonstrate that invasive pathogen risk management can benefit from a multidisciplinary approach that incorporates growers' perceptions and behavior.  相似文献   

17.
转基因耐草甘膦作物的环境安全性   总被引：1，自引：0，他引：1  
世界每年因草害造成的作物产量损失达950亿美元,为了简便有效地防除多种杂草,农民希望喷施杀草谱广的除草剂。转基因耐除草剂作物的种植为农民提供了更多的除草剂选择,在扩大杀草谱、提高除草效果、增加作物安全性、改善环境、简化栽培等方面起到了积极作用。转基因耐除草剂作物的大面积种植也引起了全球对其环境安全问题的广泛关注。本文以耐草甘膦作物为例,对国内外环境安全的相关研究结果进行归纳和总结,以期为我国耐草甘膦转基因作物的环境安全评价及耐草甘膦作物的管理提供参考。  相似文献   

18.
Glyphosate-resistant (GR) crops have been sold commercially in the USA since 1996. The use of glyphosate alone or with conventional pre- and post-emergence herbicides with different modes of action gives growers many options for affordable, safe, easy, effective wide-spectrum weed control. Despite the overwhelming popularity of this technology, technical issues have surfaced from time to time as US growers adopt these crops for use on their farms. The types of concern raised by growers vary from year to year depending on the crop and the environment, but include perceptions of increased sensitivity to diseases, increased fruit abortion, reduced pollination efficiency, increased sensitivity to environmental stress, and differences in yield and agronomic characteristics between transgenic and sister conventional varieties. Although several glyphosate-resistant crops are commercially available, maize, soybean and cotton constitute the largest cultivated acreage and have likewise been associated with the highest number of technical concerns. Because glyphosate is rapidly translocated to and accumulates in metabolic sink tissues, reproductive tissues and roots are particularly vulnerable. Increased sensitivity to glyphosate in reproductive tissues has been documented in both glyphosate-resistant cotton and maize, and results in reduced pollen production and viability, or increased fruit abortion. Glyphosate treatments have the potential to affect relationships between the GR crop, plant pathogens, plant pests and symbiotic micro-organisms, although management practices can also have a large impact. Despite these potential technical concerns, this technology remains popular, and is a highly useful tool for weed control in modern crop production.  相似文献   

19.
To promote integrated weed management (IWM) implementation in Europe, robust evidence on the sustainability of such tools and strategies is needed to motivate their adoption by stakeholders. This can only be achieved through assessing and validating them at real farm scale and using existing farm equipment, under diverse climatic and soil conditions representative of European agriculture. In 2013 and 2014, 12 on‐farm experiments (i.e. real field conditions on commercial farms, with natural weed flora) were conducted in four important European grain maize‐producing regions comparing the efficacy of herbicide band application integrated with inter‐row mechanical weeding as a potential IWM tool with the conventional broadcast herbicide application (CON) used by the farms. The IWM tools tested were as follows: (i) early post‐emergence herbicide band application combined with hoeing, followed by a second hoeing in southern Germany, (ii) early post‐emergence herbicide band application followed by hoeing in eastern Hungary and central Slovenia and (iii) pre‐emergence herbicide band application followed by hoeing in northern Italy. Herbicide band application integrated with hoeing provided good and partial weed control along and between maize rows respectively. No significant yield differences were detected between IWM and CON. IWM greatly reduced herbicide input and was economically sustainable over the duration of this study with no significant difference in gross margin compared with CON in all cases. This IWM tool could therefore be considered for implementation in European maize systems.  相似文献   

20.
Crop disease not only threatens global food security by reducing crop production at a time of growing demand, but also contributes to greenhouse gas (GHG) emissions by reducing efficiency of N fertiliser use and farm operations and by driving land use change. GHG emissions associated with adoption of reduced tillage, organic and integrated systems of field crop production across the UK and selected regions are compared with emissions from conventional arable farming to assess their potential for climate change mitigation. The reduced tillage system demonstrated a modest (<20%) reduction in emissions in all cases, although in practice it may not be suitable for all soils and it is likely to cause problems with control of diseases spread on crop debris. There were substantial increases in GHG emissions associated with the organic and integrated systems at national level, principally due to soil organic carbon losses from land use change. At a regional level the integrated system shows the potential to deliver significant emission reductions. These results indicate that the conventional crop production system, coupled to reduced tillage cultivation where appropriate, is generally the best for producing high yields to minimise greenhouse gas emissions and contribute to global food security, although there may be scope for use of the integrated system on a regional basis. The control of crop disease will continue to have an essential role in both maintaining productivity and decreasing GHG emissions.  相似文献   

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