Incorporating climate change into pest risk models for forest pathogens : a role for cold stress in an era of global warming?

Climate change may alter the distribution and activity of native and alien pathogens that infect trees and, in severe cases, cause tree death. In this study, potential future changes in climate suitability are investigated for three forest pathogens that occur in western North America: the native Arceuthobium tsugense subsp tsugense, hemlock dwarf mistletoe, and two alien invasive species, Dothistroma septosporum, the cause of red band needle blight or Dothistroma needle blight, and Phytophthora ramorum, the cause of sudden oak death or ramorum blight. Specifically, the software CLIMEX is used to calculate Cold-Stress, Heat-Stress, and Dry-Stress indices for each pathogen in 98,224 grid cells in North America. Downscaled climate projections from the general circulation models CGCM1, CSIROMk2, and HadCM3 drive forecasts for 2020, 2050 and 2080. These climate projections are then analyzed to forecast shifts in the geographic extent of abiotic stresses that are severe enough to directly kill pathogen propagules and prevent year-round establishment of these pathogens. Cold stress currently has a major impact on climate suitability for all three pathogens; heat stress is likely to become more significant in the future. I forecast that the geographic extent of cold stress will decline from its current levels by a constant 5% (} 1%) of all grid cells in each 30-yr projection horizon for all three pathogens. Forecasts suggest the extent of heat stress will increase concurrently by 4% (+/- 1%) in each 30-yr projection horizon. Drought stress shows no consistent trend over time. No disproportionate effect of climate change on the two alien invasive pathogens over the native is forecasted. These results suggest that forecasts of future climate suitability for pathogens based on historical climate normals are accurate for less than 30 yrs. Adaptive management strategies in forestry will be needed to respond as these changes unfold

Could natural selection change the geographic range limits of light brown apple moth (Lepidoptera, Tortricidae) in North America?

We artificially selected for increased freeze tolerance in the invasive light brown apple moth. Our results suggest that, by not accounting for adaptation to cold, current models of potential geographic distributions could underestimate the areas at risk of exposure to this species

Evaluation of Experimental Populations and Glandular-Haired Varieties of Alfalfa for Alfalfa Blotch Leafminer (Diptera: Agromyzidae) Feeding Injury

Following the spread of the alfalfa blotch leafminer, Agromyza frontella (Rondani) (Diptera: Agromyzidae), into Minnesota and Wisconsin U.S.A. during 1994-1997, three field trials were conducted in Minnesota to assess the potential for leafminer resistance among several sources of alfalfa (Medicago sativa), germplasm. In 1998, 86 entries were evaluated, most of which were experimental populations. In addition, six commercial varieties of alfalfa were evaluated. Of the six varieties, four had been bred for various levels of glandular-hair expression, specifically for resistance to the potato leafhopper, Empoasca fabae (Harris) (Homoptera: Cicadellidae). In two of three trials, we found no significant differences in leafmining injury to trifoliolates among the 86 entries, or among glandular-haired and traditional commercial varieties. At one location, ‘Arrest,’ ‘Ameriguard 301,’ and ‘DK 121 HG’ incurred significantly less pinhole injury than the glandular-haired variety ‘5347 LH’ or the commercial standard, ‘5454.’ However, after accounting for both pinhole and leafmining injury, only ‘Arrest’ and ‘Ameriguard 301’ had less injury than ‘5347 LH,’ ‘DK 121 HG,’ or the standard ‘5454.’ The low levels of resistance to A. frontella injury, among glandular-haired commercial alfalfa varieties and numerous experimental populations M. sativa, confirm the need for alternative A. frontella management strategies such as biological control and possible manipulation of harvest schedules

Distribution of an Exotic Pest, \u3ci\u3eAgromyza Frontella\u3c/i\u3e (Diptera: Agromyzidae), in Manitoba, Canada.

Agromyza frontella is an exotic alfalfa pest from Europe that was first detected in North America in 1968 and has since spread westward into Ontario and the north central United States. Informal surveys had detected A. frontella in Manitoba, but its distribution throughout this province was unknown. In 1998 we collected alfalfa stems to detect plant damage and sweep samples to detect adult A. frontella and the parasitoid Dacnusa dryas throughout the alfalfa growing region of Manitoba. In south central Manitoba, 100% of stems were damaged by A. frontella, and\u3e 100 adults/10 sweeps were recorded at several sites. In west central Manitoba, no plants were damaged and \u3c 10 adults/10 sweeps were observed. We believe this region to be near the western edge of A. frontella distribution. The most important introduced parasitoid of A. frontella, D. dryas, was not detected which suggests that D. dryas has not invaded Manitoba

Examining the CDCynergy Event Assessment Tool: An Investigation of the Anthrax Crisis in Boca Raton, Florida

This paper examines the dependability of the Event Assessment Tool over time. The latter is part of a CD-ROM-Emergency Risk Communication CDCynergy-distributed primarily to public information officers in the United States by the Centers for Disease Control and Prevention. The Event Assessment Tool is designed to aid emergency professionals in identifying the magnitude of a crisis event and to suggest appropriate actions to confront such a situation. Applied twice during the 2001 anthrax bioterrorism crisis in Boca Raton, Florida, the tool functioned in a binary manner by first indicating a moderate crisis level (on 4 October) and then four days later (on 8 October) a highly intense crisis, suggesting that it is time sensitive. This anthrax event provides an opportunity for crisis and disaster managers to understand the dynamic nature of crises. Rapid changes during these types of events suggest that any metric used to predict intensity must account for this variability. Additional limitations and implications of the tool are discussed

Invasive alien species in the food chain : advancing risk assessment models to address climate change, economics and uncertainty

Economic globalization depends on the movement of people and goods between countries. As these exchanges increase, so does the potential for translocation of harmful pests, weeds, and pathogens capable of impacting our crops, livestock and natural resources (Hulme 2009), with concomitant impacts on global food security (Cook et al. 2011)

Discerning the Effect of the Relationship Between Disclosure and Responsiveness On Depression, Anxiety, and Compassion Fatigue Among Veterinarians

OBJECTIVE Previous scholarship has posited that veterinarians experience more anxiety, depression, and compassion fatigue symptoms than the general population. Disclosure of psychological stressors, combined with positive responsiveness, may reduce psychological symptoms. The goal of this study was to test the relationships between disclosure, responsiveness, compassion fatigue, anxiety, and depression. SAMPLE 230 veterinarians from a private Facebook online support group. PROCEDURES Veterinarians from a private Facebook online support group were administered a cross-sectional survey using established scales measuring disclosure, responsiveness, compassion fatigue, anxiety, and depression. All scales reported strong reliability and validity. RESULTS Pearson correlations and mediation models were used to analyze the data. A small, negative, direct relationship between disclosure and depression was found, yet the more interesting results were that responsiveness had a significant, indirect effect on the relationship between disclosure and compassion fatigue, anxiety, and depression. CLINICAL RELEVANCE Disclosure may be related to decreased experiences of compassion fatigue, anxiety, and depression when responsiveness is also present. Veterinarians may benefit from improved mental well-being knowing that there are opportunities to disclose concerns to peers. Additionally, fellow veterinarians can benefit from understanding how to respond to disclosures in a positive, nonstigmatizing manner

Distribution of an Exotic Pest, \u3ci\u3eAgromyza Frontella\u3c/i\u3e (Diptera: Agromyzidae), in Manitoba, Canada.

Agromyza frontella is an exotic alfalfa pest from Europe that was first detected in North America in 1968 and has since spread westward into Ontario and the north central United States. Informal surveys had detected A. frontella in Manitoba, but its distribution throughout this province was unknown. In 1998 we collected alfalfa stems to detect plant damage and sweep samples to detect adult A. frontella and the parasitoid Dacnusa dryas throughout the alfalfa growing region of Manitoba. In south central Manitoba, 100% of stems were damaged by A. frontella, and\u3e 100 adults/10 sweeps were recorded at several sites. In west central Manitoba, no plants were damaged and \u3c 10 adults/10 sweeps were observed. We believe this region to be near the western edge of A. frontella distribution. The most important introduced parasitoid of A. frontella, D. dryas, was not detected which suggests that D. dryas has not invaded Manitoba

Russian wheat aphids (Diuraphis noxia) in China: Native range expansion or recent introduction?

In this study, we explore the population genetics of the Russian wheat aphid (RWA) (Diuraphis noxia), one of the world’s most invasive agricultural pests, in north-western China. We have analysed the data of 10 microsatellite loci and mitochondrial sequences from 27 populations sampled over 2 years in China. The results confirm that the RWAs are holocyclic in China with high genetic diversity indicating widespread sexual reproduction. Distinct differences in microsatellite genetic diversity and distribution revealed clear geographic isolation between RWA populations in northern and southern Xinjiang, China, with gene flow interrupted across extensive desert regions. Despite frequent grain transportation from north to south in this region, little evidence for RWA translocation as a result of human agricultural activities was found. Consequently, frequent gene flow among northern populations most likely resulted from natural dispersal, potentially facilitated by wind currents. We also found evidence for the longterm existence and expansion of RWAs in China, despite local opinion that it is an exotic species only present in China since 1975. Our estimated date of RWA expansion throughout China coincides with the debut of wheat domestication and cultivation practices in western Asia in the Holocene. We conclude that western China represents the limit of the far eastern native range of this species. This study is the most comprehensive molecular genetic investigation of the RWA in its native range undertaken to date and provides valuable insights into the history of the association of this aphid with domesticated cereals and wild grasses