Common vole (Microtus arvalis) ecology and management: implications for risk assessment of plant protection products

Common voles (Microtus arvalis) are common small mammals in some European landscapes. They can be a major rodent pest in European agriculture and they are also a representative generic focal small herbivorous mammal species used in risk assessment for plant protection products. In this paper, common vole population dynamics, habitat and food preferences, pest potential and use of the common vole as a model small wild mammal species in the risk assessment process are reviewed. Common voles are a component of agroecosystems in many parts of Europe, inhabiting agricultural areas (secondary habitats) when the carrying capacity of primary grassland habitats is exceeded. Colonisation of secondary habitats occurs during multiannual outbreaks, when population sizes can exceed 1000 individuals ha^?1. In such cases, in‐crop common vole population control management has been practised to avoid significant crop damage. The species' status as a crop pest, high fecundity, resilience to disturbance and intermittent colonisation of crop habitats are important characteristics that should be reflected in risk assessment. Based on the information provided in the scientific literature, it seems justified to modify elements of the current risk assessment scheme for plant protection products, including the use of realistic food intake rates, reduced assessment factors or the use of alternativee focal rodent species in particular European regions. Some of these adjustments are already being applied in some EU member states. Therefore, it seems reasonable consistently to apply such pragmatic and realistic approaches in risk assessments for plant protection products across the EU. © 2013 Society of Chemical Industry     

黄色灯防治害虫的研究与应用进展

黄色灯防治害虫的原理是利用蛾类昆虫对绿黄波段(500~590nm)光敏感的特性,通过干扰蛾类害虫的日节律达到降低其种群密度的目的。本文简述了黄色灯防治技术在国内外发展及应用状况、黄色灯防治效果的影响因素,以及黄色灯在防治蛾类害虫过程中对植物生理的影响,分析了黄色灯应用中存在的问题,并且对未来黄色灯的发展和应用进行了展望。     

Sampling in Precision IPM: When the Objective Is a Map

ABSTRACT Measuring and understanding spatial variation of pests is a fundamental component of population dynamics. The resulting maps can drive spatially variable pest management, which we define as precision integrated pest management (IPM). Precision IPM has the potential to reduce insecticide use and slow the rate of resistance development because of the creation of temporally dynamic refuges. This approach to IPM requires sampling in which the objective is to measure spatial variation and map pest density or pressure. Interpolation of spatially referenced data is reviewed, and the influence of sampling design is suggested to be critical to the mapped visualization. Spatial sampling created problems with poor precision and small sample sizes that were partially alleviated with choosing sampling units based on their geostatistical properties, adopting global positioning system technology, and mapping local means. Mapping the probability of exceeding a threshold with indicator kriging is discussed as a decision-making tool for precision IPM. The different types of sampling patterns to deploy are discussed relative to the pest mapping objective.     

贵州赤水桫椤叶蜂的生物学特性及其幼虫种群发生现状分析

桫椤叶蜂Rhoptroceros cyatheae(Wei et Wang,1995)是目前已知取食桫椤Alsophila spinulosa(Wall.ex Hook.) Tryon的食叶害虫,对桫椤的生长发育和繁殖造成了一定的影响.通过人工饲养观察和野外调查相结合,对桫椤叶蜂的生物学特性和发生动态进行了调查和分析....     

Implications of potential global warming on agricultural pests in Australia1

The potential influence of climate warming on the future status of agricultural pests in Australia is discussed in terms of the possible effects that changes in temperature, rainfall and weather patterns will have on the future distribution, numbers, fluctuations and movements of pest populations. Event-driven outbreaks are distinguished from rate-driven processes in pest populations. The future severity and frequency of pest outbreaks will depend on changes in the frequency of extreme weather events, some of which are related to the El Niño/Southern Oscillation phenomenon. Three scenarios are presented for geographical changes to rate-driven and to event-driven processes: little change (displacement of agroecosystems and their associated pests to new climatic optima); expansion of tropical pests, contraction of Mediterranean (winter rainfall) pests; increased pest multiplication in geographically fixed agroecosystems such as irrigation schemes and some animal production systems. There is considerable uncertainty about the future severity of outbreaks and chronic infestations because of our current difficulties in forecasting and realistically simulating population changes in agroecosystems. This probably results from the complex feedback mechanisms involving natural enemies and other factors. In Australia the overall expansion of areas affected by tropical pests portends an overall worsening of agricultural pest problems.     

基于风险评估的新疆抗虫棉种植分析

基于新疆棉铃虫生物学特性和多年的种群动态趋势,并在收集棉花种植面积、产量、棉花市场价格及棉铃虫防治费用等相关数据的基础上,采用种群模拟模型(CLIMEX模型)并结合随机模拟方法(@RISK软件),评估不同场景下棉铃虫对新疆棉花产业造成的潜在经济损失.棉铃虫种群模拟表明:随着未来气候变化,新疆棉铃虫的周增长指数(GIw)...     

The sensitivity of simulation models to temperature changes1

Insect population processes, such as development and reproduction, are dependent upon temperature. Accurate predictions of the phenology and population dynamics of insect pests require accurate recording of the temperatures experienced by the organisms. Any errors in the temperature measurements may result in spurious estimates of the pest population and, therefore, poor quality advice on the necessary control strategies. A simulation model predicting the phenology and population dynamics of the summer fruit tortrix, Adoxophyes orana, will be described. Output from the model closely resembled field observations of the population dynamics of the pest. Experimentation with the model revealed its sensitivity to small changes of temperature. The results illustrate the importance of using input recorded realistically with respect to the biology of the pests.     

对农业害虫防治策略与技术的展望

基于生态学的有害生物治理（ＥＢＰＭ）或生态管理被认为是新世纪农业有害生物防治的新对策。以经济学和生态学原则为基础的,应用系统工程的原理和方法设计的生态调控方法将越来越受到人们的重视;植保信息技术的应用,将大大提高害虫监测,预报和管理决策的水平;昆虫基因工程技术的开发,将开辟新的害虫防治途径。     

Modelling and mapping spread in pest risk analysis: a generic approach*

Assessing the likelihood and magnitude of spread is one of the cornerstones of pest risk analysis (PRA), and is usually based on qualitative expert judgment. This paper proposes a suite of simple ecological models to support risk assessors who also wish to estimate the rate and extent of spread, e.g. when modelling the dynamics of invasion and the economic impacts that may result. Models are based on simple ecological principles, such as logistic growth, radial range expansion and population growth in combination with dispersal. Different models capture different perspectives of the spread process, being based on pest density or simply presence/absence, and they compare spatially explicit and spatially implicit approaches. A case study on Diabrotica virgifera virgifera is provided for illustration. The suite of models requires further development and testing with the risk assessment community building familiarity before their more general application in PRA.     

Prediction of Pests,Diseases and Losses: Principles and Computer Applications1

Efficacy of plant protection is closely related to an appreciation of the seasonal development and population changes of harmful organisms. This necessitates national surveys on pest population dynamics and on the epiphytotics of plant diseases. From these surveys, regional forecasts can be produced to give advice to the farmers. This work needs highly sophisticated systems to cover both numerical and spatial aspects of pest situations. Thus, there is an urgent need to exploit computer applications in solving forecasting problems. However, the use of computers for forecasting the incidence of harmful organisms and losses is in its initial phase. At present, single pest and disease models prevail. Numerical aspects have been approached both empirically and experimentally. Empirical models, based on multiple regression analysis, are relatively simple and easy to use for various harmful organisms. However, simulation models of harmful organisms are expected to lead to much more reliable results, although, so far, little experience is available on their predictive powers in crop protection. Spatial aspects have been approached with a routine computer mapping technique, which seems to be an effective tool for recognizing and forecasting distribution trends, while loss predictions can be based on crop models, incorporating submodels forecasting the incidence of harmful organisms. The prospect for operational use, in forecasting, of the computer techniques mentioned is discussed.     

Loop-mediated isothermal amplification for rapid identification of biotypes B and Q of the globally invasive pest Bemisia tabaci, and studying population dynamics

BACKGROUND: Bemisia tabaci, the sweetpotato whitefly, is a globally invasive pest that causes serious agricultural damage by transmitting plant viruses. This pest forms a cryptic species complex that displays morphologically indistinguishable biotypes. Among them, the B and Q biotypes are the most important pests worldwide. Because they have different levels of insecticide resistance, these biotypes must be identified in order to achieve proper pest control. Therefore, a convenient, rapid and specific detection method for identifying the two biotypes is necessary. RESULTS: Loop‐mediated isothermal amplification (LAMP) was employed for rapid identification of B. tabaci B and Q biotypes. By combining a quick DNA extraction method, identification of the two biotypes was achieved within 1 h of detection time. The LAMP assay was applied to study the dynamics of B. tabaci biotypes both in the field and in greenhouses. It was found that, while temperature may be important for population dynamics of the whitefly in the field, population dynamics in greenhouse conditions may be influenced by the types of insecticide. CONCLUSION: The newly designed LAMP assay is a simple, rapid and accurate method for identifying the B and Q biotypes. It can be conducted by non‐specialists and can contribute to pest management. Copyright © 2012 Society of Chemical Industry     

小麦禾缢管蚜种群动态的研究

本文采用平均密度（X），聚块性指标（m/m）和有蚜株率（F）对小麦禾缢管蚜种群动态进行模糊聚类分析。找出了其种群消长的4个时期：点片发生期，始盛期，猖獗期和衰退期；防治重点应在始盛期，即瓢虫卵期，以达到经济有效，充分保护利用天敌的目的。     

Quantitative and qualitative analysis of accidental insect pest introduction into Switzerland and its implications for plant protection1

The purpose of this study is to assess the characteristics of accidental introduction of pest organisms into Switzerland by means of international plant trade, and to discuss its consequences for the development of plant protection strategies. We found substantial levels of infestation in samples of all producing countries included in the study. Since the use of synthetic pesticides is the main basis of pest control in the ornamental industry, the results of this study indicate that chemical pest control has reached a limit above which no further reduction of pest population levels is possible. The increased pesticide tolerance of many arthropod pests is mainly due to increased levels of resistance to pesticides caused by their excessive use. Therefore, alternative methods supplementing pesticide use are required to develop an optimal pest management strategy for the future. It is proposed that, in the Swiss ornamental production industry, pest monitoring should be the first step in this direction.     

Physiologically based demographic models streamline identification and collection of data in evidence‐based pest risk assessment

The distribution and abundance of species that cause economic loss (i.e., pests) in crops, forests or livestock depends on many biotic and abiotic factors that are thought difficult to separate and quantify on geographical and temporal scales. However, the weather‐driven biology and dynamics of such species and of relevant interacting species in their food chain or web can be captured via mechanistic physiologically based demographic models (PBDMs). These models can be implemented in the context of a geographic information system (GIS) to predict the potential geographic distribution and relative abundance of pest species given observed or climate change scenarios of weather. PBDMs may include bottom‐up effects of the host on pest dynamics and, if appropriate, the top‐down action of natural enemies. When driven by weather, PBDMs predict the phenology, age structure and abundance dynamics at one or many locations enabling the distribution of the interacting species to be predicted across wide geographic areas. PBDMs are able to capture relevant ecosystem complexity within a modest number of measurable parameters because they use the same ecological models of analogous resource acquisition and allocation processes across all trophic levels. The use of these analogies makes parameter estimation easier as the underlying functions are known. This is a significant advantage in cases where the biological data available to build an evidence base for pest risk assessment is sparse.     

DYMEX模型在棉铃虫种群动态中的应用

模型模拟是昆虫种群动态研究的重要内容,DYMEX模型是一种基于同生群概念的机理性模型,能够较真实、全面地模拟多因素影响下的种群动态,便于推广应用。棉铃虫Helicoverpa armigera自然种群动态受到诸多生态因子的影响,如气候、天敌和田间管理等,过程复杂。本文利用DYMEX 3.0软件建立了棉铃虫种群动态模型,对实验室棉铃虫种群关键生命表参数随温度变化和控制条件下杀虫剂对棉铃虫和天敌的毒杀作用分别进行了模拟;对新疆石河子121团和147团2009-2014年棉铃虫自然种群动态进行了模拟,并比较和分析了模拟结果。结果表明:(1)建立的棉铃虫DYMEX模型,在模拟实验室棉铃虫种群各阶段发育历期、存活率、成虫繁殖和寿命,以及杀虫剂对棉铃虫卵、1~3龄幼虫和天敌的毒杀影响方面,拟合优度R~2普遍高于0.6(P0.05);(2)模拟田间条件下棉铃虫种群的相对发生量和发生期与实际自然种群具有较好的一致性。因此,建立的DYMEX模型,较可靠地模拟、反映了室内控制条件和复杂生境下棉铃虫种群特征和动态,为棉铃虫室内多因素试验结果分析、因素效能分析和复杂条件下发生期和相对发生量的预测预报等方面提供有效帮助,为田间害虫的综合管理、防治提供参考。     

Biology and integrated pest management for the banana weevil Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae)

The banana weevil Cosmopolites sordidus (Germar) is the most important insect pest of bananas and plantains (Musa spp.). The larvae bore in the corm, reducing nutrient uptake and weakening the stability of the plant. Attack in newly planted banana stands can lead to crop failure. In established fields, weevil damage can result in reduced bunch weights, mat die-out and shortened stand life. Damage and yield losses tend to increase with time. This paper reviews the research on the taxonomy, distribution, biology, pest status, sampling methods, and integrated pest management (IPM) of banana weevil. Salient features of the weevil's biology include nocturnal activity, long life span, limited mobility, low fecundity, and slow population growth. The adults are free living and most often associated with banana mats and cut residues. They are attracted to their hosts by volatiles, especially following damage to the plant corm. Males produce an aggregation pheromone that is attractive to both sexes. Eggs are laid in the corm or lower pseudostem. The immature stages are all passed within the host plant, mostly in the corm. The weevil's biology creates sampling problems and makes its control difficult. Most commonly, weevils are monitored by trapping adults, mark and recapture methods and damage assessment to harvested or dead plants. Weevil pest status and control options reflect the type of banana being grown and the production system. Plantains and highland bananas are more susceptible to the weevil than dessert or brewing bananas. Banana production systems range from kitchen gardens and small, low-input stands to large-scale export plantations. IPM options for banana weevils include habitat management (cultural controls), biological control, host plant resistance, botanicals, and (in some cases) chemical control. Cultural controls have been widely recommended but data demonstrating their efficacy are limited. The most important are clean planting material in new stands, crop sanitation (especially destruction of residues), agronomic methods to improve plant vigour and tolerance to weevil attack and, possibly, trapping. Tissue culture plantlets, where available, assure the farmer with weevil-free material. Suckers may be cleaned by paring, hot water treatment and/or the applications of entomopathogens, neem, or pesticides. None of these methods assure elimination of weevils. Adult weevils may also invade from nearby plantations. As a result, the benefits of clean planting material may be limited to a few crop cycles. Field surveys suggest that reduced weevil populations may be associated with high levels of crop sanitation, yet definitive studies on residue management and weevil pest status are wanting. Trapping of adult weevils with pseudostem or corm traps can reduce weevil populations, but material and labour requirements may be beyond the resources of many farmers. The use of enhanced trapping with pheromones and kairomones is currently under study. A combination of clean planting material, sanitation, and trapping is likely to provide at least partial control of banana weevil.Classical biological control of banana weevil, using natural enemies from Asia, has so far been unsuccessful. Most known arthropod natural enemies are opportunistic, generalist predators with limited efficacy. Myrmicine ants have been reported to help control the weevil in Cuba, but their effects elsewhere are unknown. Microbial control, using entomopathogenic fungi and nematodes tend to be more promising. Effective strains of microbial agents are known but economic mass production and delivery systems need further development.     

婺源县茶尺蠖发生规律的研究

茶尺蠖是茶叶上的重要食叶性害虫,影响茶叶的产量与品质。为了解茶尺蠖的发生规律,2011—2013连续3年应用佳多牌虫情测报灯对婺源县茶尺蠖类害虫的发生种类、数量、发生期及种群动态等进行了观测,试验结果表明,茶尺蠖发生在婺源1年内可以发生4~5代、发生期长且世代重叠,主发生期在每年的6~9月。     

昆明市白车轴草上蓟马种群动态调查

对昆明市白车轴草上蓟马种类及其周年种群动态进行了调查。白车轴草上蓟马主要有西花蓟马(Fran-kliniella occidentalis)、丽花蓟马(F.intonsa)、八节黄蓟马(Thrips flavidulus)、端大蓟马(Megalurothrips distalis)、稻单管蓟马(Haplothrips aculeatus)和烟蓟马(T.tabaci),有时会出现黄胸蓟马(T.hawaiiensis)、玉米黄呆蓟马(Anaphothrips obscurus)、苏丹呆蓟马(A.sudanensis)和云南纹蓟马(Aeolothrips yunnanensis)。本文分析了前6种蓟马的周年种群动态,重点阐述了外来有害生物西花蓟马,该虫主要在3~6月发生,是此期间白车轴草上的蓟马优势种。     

The EFSA quantitative approach to pest risk assessment – methodological aspects and case studies

A new method for pest risk assessment and the identification and evaluation of risk‐reducing options is currently under development by the European Food Safety Authority (EFSA) Plant Health Panel. The draft method has been tested on pests of concern to the European Union (EU). The method is adaptable and can focus either on all the steps and sub‐steps of the assessment process or on specific parts if necessary. It is based on assessing changes in pest population abundance as the major driver of the impact on cultivated plants and on the environment. Like other pest risk assessment systems the method asks questions about the likelihood and magnitude of factors that contribute to risk. Responses can be based on data or expert judgment. Crucially, the approach is quantitative, and it captures uncertainty through the provision by risk assessors of quantile estimates of the probability distributions for the assessed variables and parameters. The assessment is based on comparisons between different scenarios, and the method integrates risk‐reducing options where they apply to a scenario, for example current regulation against a scenario where risk‐reducing options are not applied. A strategy has been developed to communicate the results of the risk assessment in a clear, comparable and transparent way, with the aim of providing the requestor of the risk assessment with a useful answer to the question(s) posed to the EFSA Plant Health Panel. The method has been applied to four case studies, two fungi, Ceratocystis platani and Cryphonectria parasitica, the nematode Ditylenchus destructor and the Grapevine flavescence dorée phytoplasma. Selected results from these case studies illustrate the types of output that the method can deliver.     

Mathematical modeling and an application of the filled function method in entomology

Macrosiphum rosae (L.) is one of the most destructive pests for Rosa damascena (Miller) when it is found in high numbers. In order to understand the population dynamics of this pest, our priority should be the determination of what extent environmental factors affect the pest population. In this study, we apply fuzzy logic modeling to visualize the population variations, which depends on the environmental factors (temperature and humidity), by using the data obtained from the field studies. After that, we determine the values of temperature and humidity that makes the number of M. rosae maximum by using the filled function method as a global optimization technique.