Insect pest management in the age of synthetic biology

Arthropod crop pests are responsible for 20% of global annual crop losses, a figure predicted to increase in a changing climate where the ranges of numerous species are projected to expand. At the same time, many insect species are beneficial, acting as pollinators and predators of pest species. For thousands of years, humans have used increasingly sophisticated chemical formulations to control insect pests but, as the scale of agriculture expanded to meet the needs of the global population, concerns about the negative impacts of agricultural practices on biodiversity have grown. While biological solutions, such as biological control agents and pheromones, have previously had relatively minor roles in pest management, biotechnology has opened the door to numerous new approaches for controlling insect pests. In this review, we look at how advances in synthetic biology and biotechnology are providing new options for pest control. We discuss emerging technologies for engineering resistant crops and insect populations and examine advances in biomanufacturing that are enabling the production of new products for pest control.     

Symbiotic microorganisms: untapped resources for insect pest control

Symbiotic microorganisms offer one route to meet the anticipated heightened demand for novel insect pest management strategies created by growing human populations and global climate change. Two approaches have particular potential: the disruption of microbial symbionts required by insect pests, and manipulation of microorganisms with major impacts on insect traits contributing to their pest status (e.g. capacity to vector diseases, natural enemy resistance). Specific research priorities addressed in this article include identification of molecular targets against which highly specific antagonists can be designed or discovered, and management strategies to manipulate the incidence and properties of facultative microorganisms that influence insect pest traits. Collaboration with practitioners in pest management will ensure that the research agenda is married to agricultural and public health needs.     

我国农业害虫综合防治研究现状与展望

害虫综合防治作为农业生产的一项重要策略,在农业可持续发展中具有举足轻重的作用。近年来,针对我国害虫防治所存在的技术需求,科技部等部门先后通过973计划、863计划、科技支撑计划和农业行业专项等对重要害虫防治研究立项支持。通过这些项目的实施,我国建成了一支由国家和省级科研单位和大学组成的专业科研队伍和研究平台,对害虫监测预警技术、基于生物多样性保护利用的生态调控技术、害虫生物防治技术、化学防治技术、抗虫转基因作物利用技术等方面的研究取得了一系列的重要进展,研究建立了棉花、水稻、玉米、小麦和蔬菜等作物重要害虫的综合防治技术体系,并在农业生产中发挥了重要作用。以基因工程和信息技术为代表的第二次农业技术革命的到来,推动了害虫综合防治的理论发展,为害虫综合防治技术的广泛应用提供了新的机遇。地理信息系统、全球定位系统等信息技术和计算机网络技术的应用,提高了对害虫种群监测和预警的能力和水平,转基因抗虫作物的商业化种植等技术的应用显著增强了对害虫种群的区域性调控效率。针对产业结构调整和全球气候变化所带来的害虫新问题,进一步发展IPM新理论与新技术将成为我国农业昆虫学研究的重要方向之一。     

Role of nanotechnology in agriculture with special reference to management of insect pests

Nanotechnology is a promising field of interdisciplinary research. It opens up a wide array of opportunities in various fields like medicine, pharmaceuticals, electronics and agriculture. The potential uses and benefits of nanotechnology are enormous. These include insect pests management through the formulations of nanomaterials-based pesticides and insecticides, enhancement of agricultural productivity using bio-conjugated nanoparticles (encapsulation) for slow release of nutrients and water, nanoparticle-mediated gene or DNA transfer in plants for the development of insect pest-resistant varieties and use of nanomaterials for preparation of different kind of biosensors, which would be useful in remote sensing devices required for precision farming. Traditional strategies like integrated pest management used in agriculture are insufficient, and application of chemical pesticides like DDT have adverse effects on animals and human beings apart from the decline in soil fertility. Therefore, nanotechnology would provide green and efficient alternatives for the management of insect pests in agriculture without harming the nature. This review is focused on traditional strategies used for the management of insect pests, limitations of use of chemical pesticides and potential of nanomaterials in insect pest management as modern approaches of nanotechnology.     

The impact of secondary pests on Bacillus thuringiensis (Bt) crops

The intensification of agriculture and the development of synthetic insecticides enabled worldwide grain production to more than double in the last third of the 20th century. However, the heavy dependence and, in some cases, overuse of insecticides has been responsible for negative environmental and ecological impacts across the globe, such as a reduction in biodiversity, insect resistance to insecticides, negative effects on nontarget species (e.g. natural enemies) and the development of secondary pests. The use of recombinant DNA technology to develop genetically engineered insect‐resistant crops could mitigate many of the negative side effects of insecticides. One such genetic alteration enables crops to express toxic crystalline (Cry) proteins from the soil bacteria Bacillus thuringiensis (Bt). Despite the widespread adoption of Bt crops, there are still a range of unanswered questions concerning longer term agro‐ecosystem interactions. For instance, insect species that are not susceptible to the expressed toxin can develop into secondary pests and cause significant damage to the crop. Here, we review the main causes surrounding secondary pest dynamics in Bt crops and the impact of such outbreaks. Regardless of the causes, if nonsusceptible secondary pest populations exceed economic thresholds, insecticide spraying could become the immediate solution at farmers’ disposal, and the sustainable use of this genetic modification technology may be in jeopardy. Based on the literature, recommendations for future research are outlined that will help to improve the knowledge of the possible long‐term ecological trophic interactions of employing this technology.     

浅谈害虫成虫防治技术

目前害虫防治中的一系列问题如害虫幼虫抗药性上升、害虫天敌被大量杀伤、人畜中毒、环境污染与土壤农药残毒日趋严重 ,使以成虫为目标虫态或防治对象而开展的成虫防治策略被广为接受并广泛应用。本文对目前使用的各种成虫防治技术体系进行了概括 ,并列举了成虫防治技术的特点和优点 ,以及进行成虫防治的许多实例。其中信息化合物防治和遗传防治的飞速发展为成虫防治的应用提供了多种途径。     

Insect pest management in African agriculture: Challenges in the current millenium

Pest management on a global scale experienced a total revolution after World War II when synthetic organic compounds were in agriculture and public health. However, it soon became apparent that there were many limitations in the use of chemicals for pest management. In agriculture, problems of pest resurgence, secondary pest outbreaks, pest resistance and adverse effects of pesticides on the environment, including human poisoning and toxicity to other non-target organisms, led to the search for alternative approaches to the pest outbreak problem. The 1960s produced new ideas on integrated pest management (IPM) strategies, followed by intensification of the search for biological control agents, which could be incorporated into IPM programmes. New application technologies were developed in the 1970s and 1980s and ecological approaches to the pest problem were spearheaded in the developed world in the 1990s, with extensive studies focused on the whole ecosystem. Important advances in crop production have also taken place in Africa in this century, involving adoption of high yielding varieties, fertilizer application, intensification of crop protection approaches, less shifting cultivation and more mono-cropping systems. However, these advances have led to increasing pest problems which unless tackled imaginatively and intelligently, they could become the most important constraint in crop production in the present millennium. Africa has entered the current millennium with relatively underdeveloped agriculture on a global scale and little investment in research on new pest management technologies that could be used to reduce crop losses. We are still highly dependent on pesticides for pest management. Therefore, the greatest challenges in agriculture in Africa will be the switch from a pesticide based mode of reducing losses due to pests to one that is ecosystem based, making use of insect management techniques which are ecologically and economically sound. Specifically, some of the major challenges in pest management in agriculture in Africa include; (i) reducing the dependence on pesticides, thus avoiding the limitations observed in the past 50 years; (ii) overcoming ignorance of the pest species and their associated community of parasites and predators which has dire consequences on the whole ecosystem; (iii) keeping out exotic pests, which in this millennium have had a devastating blow on the production of some crops and (iv) developing indigenous technologies for pest management (IPM, biocontrol, etc.) and making available to farmers materials for pest management which are affordable, safe, effective and environmentally friendly (e.g. microbial, botanicals, pheromones, genetically engineered products etc.). Both legislative and quarantine measures will have a significant role to play in pest management in the next millennium, but only when practised on a wider geographical area. Information technology (IT) will affect the way we acquire and make use of pest management strategies. Africa is therefore faced with the challenge of building up and improving its infrastructure and expertise on IT if it is to benefit pest management on the continent.     

Can microbial-based insecticides replace chemical pesticides in agricultural production?

Extensive use of chemical insecticides to control insect pests in agriculture has improved yields and production of high-quality food products. However, chemical insecticides have been shown to be harmful also to beneficial insects and many other organisms like vertebrates. Thus, there is a need to replace those chemical insecticides by other control methods in order to protect the environment. Insect pest pathogens, like bacteria, viruses or fungi, are interesting alternatives for production of microbial-based insecticides to replace the use of chemical products in agriculture. Organic farming, which does not use chemical pesticides for pest control, relies on integrated pest management techniques and in the use of microbial-based insecticides for pest control. Microbial-based insecticides require precise formulation and extensive monitoring of insect pests, since they are highly specific for certain insect pests and in general are more effective for larval young instars. Here, we analyse the possibility of using microbial-based insecticides to replace chemical pesticides in agricultural production.     

抗虫植物基因工程研究进展

虫害是造成农业减产的主要原因之一。据不完全统计,全世界每年因虫害引起的作物减产达总产量的15％,损失高达数千亿美元。在我国,因虫害水稻减产在lO％以上;小麦减产近20％;棉花减产在     

Not all GMOs are crop plants: non-plant GMO applications in agriculture

Since tools of modern biotechnology have become available, the most commonly applied and often discussed genetically modified organisms are genetically modified crop plants, although genetic engineering is also being used successfully in organisms other than plants, including bacteria, fungi, insects, and viruses. Many of these organisms, as with crop plants, are being engineered for applications in agriculture, to control plant insect pests or diseases. This paper reviews the genetically modified non-plant organisms that have been the subject of permit approvals for environmental release by the United States Department of Agriculture/Animal and Plant Health Inspection Service since the US began regulating genetically modified organisms. This is an indication of the breadth and progress of research in the area of non-plant genetically modified organisms. This review includes three examples of promising research on non-plant genetically modified organisms for application in agriculture: (1) insects for insect pest control using improved vector systems; (2) fungal pathogens of insects to control insect pests; and (3) virus for use as transient-expression vectors for disease control in plants.     

科学视角下的转基因技术认知和发展

转基因技术是现代生物技术的核心,在缓解资源约束、保障食物安全、保护生态环境、拓展农业功能等方面呈现出重要作用和巨大潜力。我国和世界上许多国家都把转基因技术作为抢占科技制高点、增强农业国际竞争力的战略选择。通过介绍农业转基因技术目前发展概况、舆论环境成因、应用趋势和本质特征,以及农业转基因生物安全管理的要求和情况,并对我国农业转基因技术产业发展进行思考和探索,帮助人们更好地了解转基因技术、更为科学地对待其应用和发展。     

试论拓宽生物防治范围，发展虫害可持续治理

该文针对我国生物防治资源极其丰富和农民经济实力薄弱的特点,结合我国微孢子虫治蝗和苹果园植被多样化持续治理虫害的成果,论述了应如何发展和拓宽具有我国特色的害虫生物防治,进一步提高综合防治水平,促进农业可持续发展。     

植物-昆虫间的化学通讯及其行为控制

在植物与昆虫间的化学通讯中植物气味物质起着决定性的作用,它调控着昆虫的多种行为,诸如引诱昆虫趋向寄主植物,刺激昆虫取食,引导昆虫选择产卵场所,进行传粉和防御昆虫等。有些植物则当受到食植性昆虫危害时会释出一些引诱害虫天敌的化学信号。这些化学信号是一些挥发性萜类混合物,天敌昆虫就以此来区分受害和未受害植株。尽管目前在害虫综合治理中,昆虫信息素的应用越来越显得比天然植物气味源更受重视,但是必须指出的是,昆虫信息化合物首次成功地使用于植物保护的却是天然植物气味源。在利用植物气味源作害虫测报和防治中,近年来一种简单价廉的粘胶诱捕器己成为多种害虫的标准测报工具。在害虫综合治理中利用植物气味源的技术显然是具有不可估量的潜力。文中提出了利用基因工程技术来改造植物,使植物能释放特定的驱避剂或其它控制昆虫行为的特殊气味物质的新概念。     

害虫遗传防治的研究历史与现状

作为防治或根除重大害虫最为有效的手段之一,害虫遗传防治在世界范围内被广泛采用并取得了巨大成功。本文综述了不育昆虫技术、雌性致死系统和昆虫显性致死技术等经典害虫遗传防治策略的发展历史、技术特点和应用情况。近年来,许多新的分子生物手段被不断提出并整合到害虫遗传防治策略中,包括归巢核酸内切酶基因、锌指核酸酶、转录激活因子样效应因子核酸酶、CRISPR/Cas9系统、Medea元件、Killer-Rescue系统、Wolbachia-细胞质不亲和性系统等。基于这些新的工具手段,许多国家已经在不同程度上启动了下一代害虫遗传防治项目。而我国在该领域的研究相对薄弱,需要在借鉴国外成功经验的同时,进一步加强害虫遗传防治的基础和应用研究,从而实现本地有害生物的可持续治理和外来入侵生物的有效狙击,确保我国未来的粮食和生态安全。     

Theory,Technology, and Practice of Site-Specific Insect Pest Management

Insects are usually unevenly distributed throughout an area in nature. Despite this knowledge, analytical methods and technology have limited insect pest management to uniform management decisions in the field. Recently, the methods and technology to map and analyze insect spatial distribution have been developed to a level where the uneven nature of insect populations can be considered for application of pest management tactics. This new approach to insect management is termed site-specific pest management. Site-specific pest management utilizes spatial information about pest distribution to apply control tactics only where pest density is economically high within a field. This review will detail the current status of site-specific insect pest management in agriculture, technological requirements, its limitations, and future potential.     

Molecular technologies to improve the effectiveness of the sterile insect technique

The application of the Sterile Insect Technique (SIT) in area-wide integrated pest management (AW-IPM) programmes continues to increase. However, programme efficiency can still be considerably enhanced when certain components of the technology are improved, such as the development of improved strains for mass rearing and release. These include strains that (1) produce only male insects for sterilization and release and (2) carry easily identifiable markers to identify released sterile insects in the field. Using both classical and modern biotechnology techniques, key insect pests are targeted, where SIT programmes are being implemented. The pests include mosquitoes, the Mexican fruit fly, the codling moth, the oriental fruit fly and the pink bollworm. This special issue summarizes the results of research efforts aimed at the development and evaluation of new strains to a level where a decision can be made as to their suitability for use in large scale SIT programmes. Major beneficiaries will be operational AW-IPM programmes that apply the SIT against major insect pests.     

转Bt基因抗虫棉的生态风险及治理对策

评述了转Bt基因抗虫棉的生态风险及治理对策。其生态风险主要表现在目标害虫的抗性和对非目标生物群落的变化。目标害虫与转基因抗虫棉的互相作用和抗虫棉杀虫毒素的时空表达方式是目标害虫抗性发展的主要途径。在转基因抗虫棉田中,虽然对目标害虫的防治次数大为减少,但害虫和天敌群落的稳定性仍不如常规棉田,某种次要害虫大发生的可能性较大。认为将转基因抗虫棉纳入综合防治体系并培育更加高效的抗虫棉是治理目标害虫抗性和防止次要害虫上升的重要措施。     

973项目“重大农业害虫猖獗危害的机制及可持续控制的基础研究”简介

2006年9月,国家重点基础研究发展计划(973)农业领域2006年度项目“重大农业害虫猖獗危害的机制及可持续控制的基础研究”经科技部批准正式立项启动。该项目以全系统管理思想为指导,在基因、个体、种群、生态系统等不同层次,阐明我国重大农业害虫种群分化与暴发的分子基础,解析害虫与寄主作物及天敌间的相互作用机制,建立害虫监测与预警系统,提出重大农业害虫可持续控制的新途径和新方法,为我国农业减灾、经济的可持续发展奠定科学基础。项目的主要研究内容包括:害虫生长发育与生殖调控的分子机制;害虫对环境胁迫的适应机制;杀虫药剂诱导害虫再猖獗的机制;害虫与寄主植物的协同进化;天敌与害虫的互作及控害机制;作物-害虫-天敌食物网关系及其调控机理;重大害虫区域性暴发监测与预警。项目的总体目标为:阐明害虫生长发育、种群分化的分子基础,揭示害虫种群调节的内在机制;解析作物、害虫及天敌间的互作机制,丰富和发展植物-害虫-天敌协同进化理论;阐明主要害虫区域性灾变机理,发展害虫预警新技术;发展与环境相容的、增强自然控害功能的新技术,提出重大农业害虫可持续控制的新途径和新方法;凝炼一支害虫控制基础研究的创新团队,丰富和发展我国害虫管理的科学理论与实践,提升我国有害生物防控的原始创新和集成创新能力,扩大国际影响。     

Soil‐dwelling insect pests of tree crops in Sub‐Saharan Africa,problems and management strategies—A review

This review aims to draw the attention of researchers, ecologists and farmers to the threats of soil‐dwelling insect pests on important tree crops in sub‐Saharan Africa, with a special focus on termites. It synthesizes the information on the effects of various factors affecting soil pest occurrence and damage, suggesting that the resultant undesirable effects of soil pests in this region are largely as a result of indiscriminate tree cutting, slash‐and‐burn agriculture and indiscriminate use of pesticides. Major insect orders, their host ranges and the nature of damage on selected tree crops are described. This study further critiques existing soil pest management practices, showing that majority of soil pest management practices are ineffective. Thus, management strategies like “attract and kill” approach based on entomopathogenic fungi need to be studied, developed and emphasized for the management of soil insect pests in sub‐Saharan Africa. A conclusion section attempts to offer suggestions for ways in which future work on soil pests in sub‐Saharan Africa could proceed.     

Insect transgenesis and its potential role in agriculture and human health

The ability to genetically engineer insects other than Drosophila melanogaster has further extended modern genetic techniques into important insect pest species ranging from fruit fly pests of horticulture to mosquito vectors of human disease. In only a relatively short period of time, a range of transgenes have been inserted into more than 10 insect pest species. Genetic transformation of these pest species has proven to be a very important laboratory tool in analyzing gene function and effects on phenotype however the full extension of this technology into the field is yet to be realized. Here we briefly review the development of transgenic technology in pest insect species and discuss the challenges that remain in this applied area of insect genetics and entomology.