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The highly polyphagous light brown apple moth (LBAM) (Epiphyas postvittana (Walk.): Tortricidae) is indigenous to Australia and was first found in California in 2006. It is currently found in 15 coastal counties in California, but nowhere has it reached outbreak status. The USDA projects the geographic range of LBAM will include much of Arizona and California and the southern half of the US, which together with economic estimates of potential crop losses have been used as the rationale for an eradication program in California. We report a temperature-driven demographic model to predict the likely distribution and relative abundance of LBAM using the detailed biology reported by Danthanarayana and colleagues, and climate data from 151 locations in California and Arizona for the period 1995–2006. The predictions of our model suggest that the near coastal regions of California are most favorable for LBAM, the northern Central Valley of California being less favorable, and the desert regions of Arizona and California being unfavorable. The model also predicts that LBAM populations can develop at two of the hottest locations in SE Australia where it is has long been known to occur. This reassessment of the potential distribution of LBAM in California and Arizona suggests that its likely ecological and economic impacts would be less than previously assessed by USDA and that its current pest status warrants re-evaluation.

Following a request from the European Commission, the EFSA Panel on Plant Health performed a quantitative pest risk assessment to assess whether the import of cut roses provides a pathway for the introduction of Thaumatotibia leucotreta (Lepidoptera: Tortricidae) into the EU. The assessment was limited to the entry and establishment steps. A pathway model was used to assess how many T. leucotreta individuals would survive and emerge as adults from commercial or household wastes in an EU NUTS2 region climatically suitable in a specific season. This pathway model for entry consisted of three components: a cut roses distribution model, a T. leucotreta developmental model and a waste model. Four scenarios of timing from initial disposal of the cut roses until waste treatment (3, 7, 14 and 28 days) were considered. The estimated median number of adults escaping per year from imported cut roses in all the climatically suitable NUTS2 regions of the EU varied from 49,867 (90% uncertainty between 5,298 and 234,393) up to 143,689 (90% uncertainty between 21,126 and 401,458) for the 3‐ and 28‐day scenarios. Assuming that, on average, a successful mating will happen for every 435 escaping moths, the estimated median number of T. leucotreta mated females per year from imported cut roses in all the climatically suitable NUTS2 regions of the EU would vary from 115 (90% uncertainty between 12 and 538) up to 330 (90% uncertainty between 49 and 923) for the 3‐ and 28‐day scenarios. Due to the extreme polyphagia of T. leucotreta, host availability will not be a limiting factor for establishment. Climatic suitability assessment, using a physiologically based demographic modelling approach, identified the coastline extending from the northwest of the Iberian Peninsula through the Mediterranean as area suitable for establishment of T. leucotreta. This assessment indicates that cut roses provide a pathway for the introduction of T. leucotreta into the EU. [ABSTRACT FROM AUTHOR]

Although a large part of Italy is characterized by a Mediterranean climate intrinsically highly suitable for olive cultivation, farmers may experience variable interannual yields with associated agronomic and management costs. A detailed overview of major climate stressors and their ongoing impacts on olive yield variability at a broad spatial–temporal scale across Italy could improve the understanding of how interannual olive yields are modulated by seasonal local climate and would enhance the development of actionable services to alert stakeholders of potential climate risks. We analysed aggregated olive yield data from the Italian National Statistics Institute (ISTAT) at the provincial level during 2006–2020, and several climatic variables from the Reanalysis v5 (ERA5) of the European Centre for Medium‐Range Weather Forecasts (ECMWF) as a basis to (i) explore olive yield trends and inter‐annual variations over the whole country; (ii) identify major seasonal climate stressors likely responsible for the largest variations in yield and (iii) develop a composite index that summarizes the risk of having exceptionally low yields due to the co‐occurrence of multiple stressors. To this end, we defined two extreme classes of yield, namely, exceptionally low and high yields (LY and HY, respectively) and explored the climatic variables aggregated on a bimonthly time scale that influenced yield outcomes. Our analysis showed that exceptional low yields have been erratically increasing since 2014 with temperature‐related variables having the highest impact, especially a relatively warm winter and cool early autumn. These period‐specific variables were major components of the resulting composite index predicting the likelihood of LY ranging from 28% to 49% due to increasing stress effects. Possible explanations of our findings are discussed, including the proliferation of the olive fly. We suggest the composite risk approach could lay the groundwork for an integrated meteorological seasonal forecasting system that provides timely insights on factors affecting within‐season olive yield development. [ABSTRACT FROM AUTHOR]

The use of marginal land (ML) for lignocellulosic biofuel production is examined for system stability, resilience, and eco-social sustainability. A North American prairie grass system and its industrialization for maximum biomass production using biotechnology and agro-technical inputs is the focus of the analysis. Demographic models of ML biomass production and ethanol farmer/producers are used to examine the stability properties of the ML system. A bio-economic model that maximizes the utility of consumption having the dynamics of MLs and the farmer/producers as dynamic constraints is used to examine the effects of increased conversion efficiency, input costs, risk, and levels of base resources and inputs on the competitive and societal solutions for biomass production. We posit ML abandonment after biofuel production ceases could lead to permanent land degradation below initial levels that prohibit the establishment of the original flora and fauna. (Contains 1 table, 5 figures and 1 note.)

Transgenic insecticidal Bt crops are being increasingly used worldwide, and concern is increasing about resistance and their effects on nontarget organisms. The toxin acts as a weak pesticide and, hence, the effects are subtler than those of chemical biocides. However, the toxin is ever present, but concentrations vary with age of plant and plant subunit, causing varying lethal and sublethal effects on pest survival, developmental time, and fecundity. Refuges for susceptibility to Bt occur spatially in non-Bt hosts and temporally within the crop because of time-varying toxicity and pest tolerance. Natural enemies feeding on Bt-intoxicated prey may have reduced longevity and, likely, fecundity that reduces their efficacy in controlling pest populations, and pest resurgence and secondary pest outbreaks may occur that may require insecticide use. System modeling is proposed as an efficient tool for examining the use of extant and future biotechnologies in pest control.

Yellow starthistle ( Centaurea solstitialis L) ( YST) is an invasive weed native to the Mediterranean region with a geographical centre of diversity in Turkey. It is widely established in Chile, Australia, and western North America. It arrived in California as a contaminant in alfalfa seed in 1859 and, by 2002, had infested >7.7 million hectares in the U.S.A., Biological control of YST using capitula feeding weevils, picture wing flies and a foliar rust pathogen has been ongoing in the western U.S.A. for more than three decades with limited success. Modelling and field research suggest natural enemies that kill whole plants and/or reduce seed production of survivors are good candidates for successful biological control. A candidate species with some of these attributes is the rosette weevil Ceratapion basicorne ( Illiger)., In the present study, a model of the rosette weevil is added to an extant system model of YST and its capitula feeding natural enemies and, in a GIS context, is used to assess YST control in the Palearctic region and the weevil's potential impact on YST in western U.S.A., The results obtained suggest densities of mature YST plants in western U.S.A. would be reduced by 70-80% in many areas. [ABSTRACT FROM AUTHOR]

Understanding the causes and effects of species invasions is a priority in ecology and conservation biology. One of the crucial steps in evaluating the impact of invasive species is to map changes in their actual and potential distribution and relative abundance across a wide region over an appropriate time span. While direct and indirect remote sensing approaches have long been used to assess the invasion of plant species, the distribution of invasive animals is mainly based on indirect methods that rely on environmental proxies of conditions suitable for colonization by a particular species. The aim of this article is to review recent efforts in the predictive modelling of the spread of both plant and animal invasive species using remote sensing, and to stimulate debate on the potential use of remote sensing in biological invasion monitoring and forecasting. Specifically, the challenges and drawbacks of remote sensing techniques are discussed in relation to: i) developing species distribution models, and ii) studying life cycle changes and phenological variations. Finally, the paper addresses the open challenges and pitfalls of remote sensing for biological invasion studies including sensor characteristics, upscaling and downscaling in species distribution models, and uncertainty of results. [ABSTRACT FROM PUBLISHER]

The Mediterranean Basin is a climate change and biological invasion hotspot where recent warming is facilitating the establishment and spread of invasive species, one of which is the highly destructive South American tomato leafminer (Tuta absoluta). This pest recently invaded the Mediterranean Basin where it threatens Solanaceous crops. Holistic approaches are required to project the potential geographic distribution and relative abundance of invasive species and hence are pivotal to developing sound policy for their management. This need is increasing dramatically in the face of a surge in biological invasions and climate change. However, while holistic analyses of invasive species are often advocated, they are rarely implemented. We propose that physiologically based demographic models (PBDMs) in the context of a geographic information system (GIS) can provide the appropriate level of synthesis required to capture the complex interactions basic to manage invasive species such asT. absoluta. We review the PBDMs for two invasive flies, and use them as a basis for assessing the biological data available for the development of a PBDM forT. absoluta, and in the process identify large data gaps that using the PBDM as a guide can be easily filled. Other components for an ecologically based management program for this pest (habitat modification, natural and classical biocontrol, pheromones, and others) are also reviewed. The development of a PBDM forT. absolutawould provide the basis for an interdisciplinary agroecological synthesis of the problem and the role different control tactics would play in region-specific control of the pest. [ABSTRACT FROM AUTHOR]

The new world screwworm [ Cochliomyia hominivorax (Coquerel)] was eradicated in North America, Libya and other locations using the sterile insect technique ( SIT)., To examine the role of weather in its eradication, a physiologically-based demographic model was developed and used to characterize its range of year-round persistence. Published data on developmental times, fecundity and mortality rates on temperature were used to parameterize the model. The lower and upper thermal thresholds for development are 14.5 and 43.5 °C, and the optimal temperature for survival is 27.2 °C. An index of favourability based on annual rainfall was used as an approximate estimate of the limiting effects of moisture in arid areas., The open source geographical information system software grass was used to map the simulation results, as well as county level myiasis incidence data for Texas for the 1962-1983 SIT eradication programme., Winter temperature and rainfall are shown to have a strong influence on screwworm outbreaks and in facilitating eradication in North America and Libya. Prospective analysis for the Mediterranean Basin suggests that eastern areas are most favourable for screwworm establishment (e.g. the Nile River area of Egypt)., The SIT eradication programme and its possible extension into South America are discussed., Expected +2 °C climate warming is predicted to increase the potential year-round range of screwworm in the southeast U.S.A. [ABSTRACT FROM AUTHOR]

The control of insect pests and other taxa may be a result of many factors that are difficult to separate and quantify. Introduced parasitoids, host plant resistance, pathogens and native predators led to the successful control of the spotted alfalfa aphid ( SAA; Therioaphis maculata Monell) in California and elsewhere, although the relative contribution of each factor remained largely unknown., The relative contribution of each control factor was estimated using a weather-driven physiologically-based demographic system model consisting of alfalfa, SAA, its three exotic parasitoids [ Aphelinus semiflavus Howard, Praon palitans Muesebeck and Trioxys complanatus ( Quilis)], a native coccinellid beetle [ Hippodamia convergens ( Guérin- Menéville)], a fungal pathogen [ Erynia neoaphidis Remaudière & Hennebert ( Zygomycetes: Entomophthorales)] and host plant resistance ( HPR). Daily weather data for the period 1995-2006 from 142 locations in Arizona and California were used to drive the model., The factors were introduced to the model singly or in combination to assess their effects in suppressing simulated SAA populations using SAA-days m−2 year−1 (i.e. density) as the metric of control., Data from selected runs were mapped using the geographic information system grass (http://grass.osgeo.org). The simulation data across all factor combinations, years and locations were summarized using linear multiple regression, with the dependent variable being log10 SAA-days m−2 year−1 and the independent variables being the presence-absence (0, 1) of the various factors and their interactions. Marginal analysis of the regression model (∂ y/∂ x i) enabled separation of the average effects of the different factors ( xi) given the average effects of the other factors., Alone, each factor failed to control SAA, as did combinations of the parasitoids and coccinellid predation. Control was predicted across all ecological zones only when all mortality factors were included. The marginal analysis suggests that the order of importance of the mortality factors is HPR > coccinellid beetles > T. complanatus > P. palitans > A. semiflavus > the fungal pathogen. The variability of control by coccinellid beetles and the fungal pathogen was high and hence unreliable. [ABSTRACT FROM AUTHOR]

Published bi- and tri-trophic physiologically based demographic system models having similar sub components are used to assess prospectively the geographic distributions and relative abundance (a measure of invasiveness) of six invasive herbivorous insect species across the United States and Mexico. The plant hosts and insect species included in the study are: 1) cotton/pink bollworm, 2) a fruit tree host/Mediterranean fruit fly, 3) olive/olive fly, 4) a perennial host/light brown apple moth, 5) grapevine/glassy-winged sharpshooter and its two egg parasitoids, and 6) grapevine/European grapevine moth. All of these species are currently or have been targets for eradication. The goal of the analyses is to predict and exphdn prospectively the disparate distributions of the six species as a basis for examining eradication or contaimnent efforts against them. The eradication of the new world screwworm is also reviewed in the discussion section because of its pivotal role in the development of the eradication paradigm. The models used are mechanistic descriptions of the weather driven biology of the species. Observed daily weather data (i.e., max-rain temperatures, solar radiation) from 1,221 locations across the United States and Mexico for the period 1983-2003 were used to drive the models. Soil moisture and nutrition were assumed nonlimiting. The simulation results were mapped using GRASS GIS. The mathematical underpinnings of the modeling approach are reviewed in the appendix and in the supplemental materials. [ABSTRACT FROM AUTHOR]