IPM for food storage in developing countries: 20th Century aspirations for the 21st Century

In tropical developing countries, especially in humid zones, pest infestation in stored food is inevitable. In the past, the focus of tropical storage pest management was on adapting pest control techniques with contact insecticides and fumigants that had proved effective in industrialized countries. Three decades ago it was still widely assumed that these techniques would continue to provide a panacea for the foreseeable future. At the end of the century, the reality is very different: widespread resistance; non-efficacy of surface treatments; no ‘fifth generation’ of pesticides; narrow choice of fumigants; and consumer demand for minimal or zero residues. In response, research on biorational alternatives has increased in recent years, especially on ‘additives’. By contrast, research on ecologically-based alternatives has stagnated. Studies of the synecology of storage pest communities remain very rare. Few authors have addressed the particular problems of IPM decision-making in storage, and in practice the emphasis is on pragmatic mixtures of control methods rather than a calculated application of optimum procedures in response to monitoring and risk assessment. At the end of the 20th Century, IPM in food stores is still an aspiration rather than a reality, and we still have much to learn about the ecology and behaviour of pests in the post-harvest system if we are to achieve an IPM approach to storage pests in the 21st Century.     

Networking of integrated pest management: A powerful approach to address common challenges in agriculture

Integrated pest management (IPM) is facing both external and internal challenges. External challenges include increasing needs to manage pests (pathogens, animal pests and weeds) due to climate change, evolution of pesticide resistance as well as virulence matching host resistance. The complexity of designing effective pest management strategies, which rely less heavily on the use of conventional pesticides, is another external challenge. Internal challenges include organizational aspects such as decreasing trend in budget allocated to IPM research, increasing scarcity of human expertise, lack of knowledge transfer into practice and the communication gap both at country level and between countries, and lack of multi-, inter- and transdisciplinary IPM research. There is an increasing awareness that trans-national networking is one means to overcome such challenges and to address common priorities in agriculture. A large number of stakeholders (researchers, policy makers, growers and industries) are involved in the sector of crop protection, which needs to be coordinated through effective communications and dynamic collaboration to make any IPM strategy successful. Here we discuss a decade-long IPM networking experiences in Europe emphasizing how IPM research, implementation and adoption in Europe may benefit from a broader level networking.     

Chemical control of stored product insects with fumigants and residual treatments

Integrated pest management (IPM) programs that eliminate infestations and prevent economic damage in raw commodities, food storage facilities, and milling and processing plants typically involve chemicals. They are preferred because they are often the cheapest and most efficient strategies available. When evaluating pesticides, it is important to recognize the biological and environmental factors that can affect pesticide efficacy so the insecticide can be effectively used in control programs. We illustrate these concepts with data from research studies with cyfluthrin, a pyrethroid insecticide used as a residual surface treatment, and with data from developmental research with new fumigants. These chemical pesticides and others like them could have specific applications and strategies in an IPM program for post harvest pests well into the 21st Century.     

Trials of an integrated pest management programme based on selective pesticides in English apple orchards

An integrated pest management (IPM) programme for apple involving selective insecticides applied in response to monitoring and using non-acaricidal fungicides was compared with a routine ‘calendar’ broad-spectrum programme over a 5-year period. This IPM system optimized the effect of natural enemies. From the second season onwards the predacious phytoseiid mite, Typhlodromus pyri, reached sufficient numbers to regulate Panonychus ulmi at low, non-damaging numbers. T. pyri also suppressed apple rust mite, Aculus schlechtendali, over most of this period. No acaricides were required on the IPM plots in the last 3 years of the trial. Small reductions in the number of insecticide/acaricide applications were made on the IPM plots but insect damage to fruit, especially by lepidopterous larvae, was higher than on the broad-spectrum plots. Several pests now rarely seen in commercial orchards built up on IPM plots and required specific treatments. The results are discussed in relation to further development of a commercially applicable IPM system.     

Managing storage pests of maize: Farmers' knowledge,perceptions and practices in western Kenya

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.     

Adaptation of approaches to pest control in low-input agriculture

Adaptation and acceptance of pest control in low-input agriculture will be largely influenced by the approach used to manage soil-borne pests. A single tactic approach, consisting of the routine application of a broad spectrum biocide or biocides to disinfest soil is not compatible with the goal of minimizing inputs and will not have wide-scale applicability in low-input production systems. An integrated pest management (IPM) approach can be compatible with low-input systems but is often difficult to implement due to inherent constraints associated with identifying and treating organisms in the soil. Additionally, IPM will require more intensive knowledge of biological interactions in the soil and the timely management of that information, which may not be practical in low input systems. A pro-active approach, in which the production system is designed to avoid the outbreak of pests, minimizes the use of inputs in crop production by reducing the need for intervention treatments. Traditionally, the impact of soil-borne pests is not considered until after the production system has been designed and implemented. Combining biologically based pest control methods with a production system designed to minimize their impacts offers the most sustainable approach for low-input agriculture.     

Crop protection services in Southern Africa

Despite the considerable progress made in different farming systems in Southern Africa, effective crop protection services remain a major constraint in their agricultural production systems. Factors responsible for these limitations include the following: the low government priorities still accorded crop protection services; the scarcity or complete lack of trained experienced professional and technical crop protection personnel; the fact that techniques for pest and disease control either are not available to small-scale farmers, or, where available, are not appropriate to the local situation; the inadequacy or lack of cooperation and communication between scientists, extension workers and farmers. A rigorous research, extension and training programme with an efficient infrastructure is advocated. In order to set priorities for appropriate integrated pest management (IPM), a standardized survey of pests of important food crops as well as losses suffered by small-scale farmers in each country of the region is imperative. The crop protection services can also be strengthened through the establishment of a Southern African Development Coordination Conference (SADCC) Crop Protection Collaborative Network to coordinate crop protection activities, as described below.     

Effects of training on acquisition of pest management knowledge and skills by small vegetable farmers

Effects of farmer field school (FFS) and the conventional (classroom lectures) training on acquisition of pest management knowledge and skills by small vegetable farmers were studied in Yunnan province, China from 2003 to 2007. There were significant gains of knowledge about vegetable pests, natural enemies, insect and disease ecology and pest management among the FFS farmers, but were no significant improvements of knowledge among the conventional trained farmers. Vegetable FFS enabled farmers to learn simple knowledge as well as complex IPM knowledge. In contrast, the conventional training only improved vegetable farmers' simple knowledge. The potential and limitations of FFS as a unique extension tool to disseminate the complex knowledge of IPM to smallholder farmers were demonstrated.     

Intelligent geographic information systems and integrated pest management

Research in integrated pest management (IPM) has resulted in the development of an immense knowledge base that requires computer-aided methodologies for integration, interpretation and delivery. Examined in this paper are four issues of concern to decision-making and problem-solving for IPM. First, the IPM enterprise is examined in the context of contemporary landscape ecology principles. The functional unit for IPM is defined to be the ecotope (a term intended to embody concepts of ecosystem functionality in the context of topographical dimension). A landscape consists of a mosaic of interacting ecotopes. The scope of IPM extends beyond forest and farm management and includes issues associated with environmental management. Second, the utility of geographic information systems (GISs) for IPM is considered. GISs add a new dimension to IPM in that they provide a mechanism for dealing with site-specific and spatially referenced data. The addition of methodologies from artificial intelligence expert systems, in particular, permits integration of qualitative knowledge of human experts with quantitative information that is the product of research. The resulting software system is termed an intelligent geographic information system, IGIS. This system allows for automated interpretation within and among landscape data themes. The product is an interpretative map or a tabular report. Third, utility of the IGIS approach is illustrated by an example involving habitat delineation for an endangered species, the Houston toad. In this example a simple rulebase is developed that defines habitat locations that would be suitable for the toad. Fourth, a concept and method for integrating the different types of knowledge available for IPM (published research results and reports, spatial and tabular databases, simulation models, and observations and experiences of human experts) is described. This software system, the knowledge system environment, retains the unique features of an IGIS but is more useful in that it employs the full measure of knowledge available from IPM. With new technology from computer science and concepts from information engineering, it has been possible to formulate a new conceptual model of IPM that incorporates both the information systems needed as well as the activities required for implementation of IPM.     

Perspectives of integrated pest management

Integrated pest management (IPM) programmes require joint interdisciplinary scientific efforts to assemble sound information about: (1) the ecological basis of the pest problem; (2) factors in the agroecosystem that can be manipulated to make the crop environment unfavourable for pests; (3) pest and natural enemy population trends to determine if and when pesticide treatments are necessary; and (4) the benefits and risks of the IPM strategy for agriculture and society. The IPM technology is complex and this is partly why implementation of IPM has been slow. Projections are that if IPM is adopted by agriculture, pesticide use could be reduced by 35–50% from present use levels. Concurrently there would be a reduction in environmental and social problems caused by pesticides.     

Factors determining adoption of integrated pest management by vegetable growers in Nakhon Ratchasima Province,Thailand

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.     

Pesticide use in rice and rice–fish farms in the Mekong Delta, Vietnam

Pest management practices among rice and rice–fish farmers and their perception of problems related to pests and pesticides were surveyed in the Mekong Delta. A total number of 64 different pesticides were identified during the survey. Approximately 50% were insecticides, 25% were fungicides and 25% were herbicides. The main insecticides used were pyrethroids (42%) carbamates (23%) and cartap (19%). Non-IPM farmers used twice as many pesticides as IPM farmers. Their application frequency and the amount of active ingredient used were 2–3 times higher per crop, as compared to IPM farmers. During the last three years IPM farmers estimated that they had decreased the amount of pesticides used by approximately 65%, while non-IPM farmers said that they had increased the amount of pesticide used by 40%. Also, farmers growing fish in their rice fields used less pesticide than farmers growing only rice, as pesticides adversely affect cultures of fish. Taking a long-term perspective integrated rice–fish farming with IPM practices provides a sustainable alternative to intensive rice mono-cropping, both from an economic as well as an ecological point of view.     

An Australian approach to IPM in cotton: integrating new technologies to minimise insecticide dependence

Insect pests represent a severe limitation for cotton production in many regions of the world. Key pests include several Heliothine moths, which are well adapted to exploit cropping systems associated with cotton and often evolve resistance to pesticides. While many components of IPM have been implemented, the main intervention for the management of key pests continues to be insecticides. This reliance on pesticides brings significant environmental liabilities of off-target drift, chemical residues and resistance. IPM must be founded on a thorough understanding of the ecology of pest and beneficial species and their interaction with the crop. The emerging era of insect resistant transgenic cottons offers real prospects to provide a foundation for more sustainable, economically acceptable IPM with the integration of a range of non-chemical tactics and much less reliance on pesticides.     

Current control methods for diamondback moth and other brassica insect pests and the prospects for improved management with lepidopteran-resistant Bt vegetable brassicas in Asia and Africa

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.     

The role of parasitic Hymenoptera in integrated pest management in fruit orchards

Parasitic Hymenoptera are some of the most abundant natural enemies of all fruit pests. Their role is rather variable in relation to the type of agroecosystem. Several approaches (introduction of exotic species, inoculative and inundative releases, measures for conservation of the existing species, etc.) can be implemented to increase the role of the parasitoids in controlling pest species. Classical biological, when applicable, as against several citrus pests, is still the most ecologically and economically sound method. The role parasitoids play in the regulation of pest populations remains uncertain, but much evidence for its importance as a regulatory factor comes from biological control programs.     

大豆蚜的研究进展

大豆蚜是我国大豆的一种主要害虫,近几年来,大豆蚜已先后侵入美国、加拿大和澳大利亚等大豆种植区,成为世界性的重要农业害虫.本文综述了大豆蚜翅蚜分化、寄主适应性、嗅觉的进化、取食行为、大豆抗性、天敌及防治方法等方面的研究进展.     

Movento, an innovative ambimobile insecticide for sucking insect pest control in agriculture: Biological profile and field performance

The tetramic acid derivative spirotetramat (brand name Movento^®), has shown an outstanding performance against sucking insect pests in laboratory and greenhouse assays as well as in semi-field and field trials. The product acts as an inhibitor of lipid biosynthesis and affects juvenile stages with additional effects on adult fecundity. There is no cross-resistance to any other insecticide. After foliar application spirotetramat penetrates through the leaf cuticle and is translocated as spirotetramat-enol via xylem and phloem, up to growing shoots and down to roots. This full ambimobility or two-way systemicity (phloem and xylem transport) ensures the control of hidden and soil living sucking pests after foliar application and protects new shoots. The worldwide field development of spirotetramat in Bayer CropScience AG resulted in numerous uses against many species of whiteflies, aphids, scales (soft and armoured scales), mealy bugs, psyllids and selected thrips species in vegetables, cotton, soybean, pome and stone fruit, grapes, hop, citrus, nut trees and banana. The new mode of action renders spirotetramat as an excellent rotation partner with existing products for the management of aphid, whitefly and psyllid populations, which are frequently resistant to conventional insecticides. Moreover, only low adverse effects have been found on beneficial arthropods, which make the product suitable for modern integrated pest management (IPM) systems. These unique properties contribute to safeguarding the crop yield potential both in quality and quantity. In this paper, the new chemistry is presented, compared with standard insecticides and novel applications in IPM systems are discussed.     

Cropping Systems and Integrated Pest Management: Examples from Selected Crops

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.     

Net choice is key to the augmentorium technique of fruit fly sequestration and parasitoid release

In Reunion Island, tephritid fruit flies are the main pests of fruit and vegetable crops, causing severe yield losses. Instead of the curative approach to reducing populations, this study focused on a particular sanitation technique, which forms the basis of Integrated Pest Management (IPM) in this context, using a tent-like structure called an “augmentorium” the aim of which is to contribute to controlling these pests. This structure sequesters adult flies emerging from infested fruit while allowing the parasitoids to escape, via a net placed at the top of the structure. The size of four nets was tested in the laboratory in order to include the most effective one in an augmentorium prototype adapted to the conditions of Reunion Island. The mesh finally selected (hole area 3.00 mm²) proved to be perfectly effective with 100% sequestration of adult flies (Ceratitis capitata, Bactrocera cucurbitae, Bactrocera zonata). In addition, 100% of the parasitoids (Fopius arisanus and Psyttalia fletcheri) were able to escape from the cage through the mesh if they chose to do so. Farmers were enthusiastic about using the augmentorium prototype. Implications for the use of this technique in Reunion Island are discussed.