With West Nile numbers up, WTOP asks Professor Mike Raupp, mosquito season-when will it end?
https://wtop.com/health-fitness/2018/09/west-nile-virus-up-dramatically-mosquito-season-still-not-over/ Spider feeding live! Explore the world of entomology and see the fascinating Black and Yellow Garden Spider (Argiope aurantia) on display in the Plant Sciences Building 2nd floor lobby. Watch feeding every Tuesday & Thursday at 12:00pm beginning August 23rd. Check out our Summer 2018 Entomology Department newsletter to see what we've been up to! Content includes news on publications, awards, defenses and much more. Is there something you'd like to see in the Fall 2018 edition? Let us know by sending an e-mail to umdentomology@umd.edu. Enjoy! Written by Kiley Gilbert, Bug Camp Assistant Director If you are one of the folks working in the Plant Sciences Building during the summer, chances are you at least glimpsed the parade of youths toting armfuls of nets, bug houses, water bottles, and various pieces of indeterminate organic matter throughout the halls. If you happened to miss this aforementioned spectacle, perhaps you still overheard powerful and echoing cries along the lines of, “My daddy long legs are fighting!” and “Look! Look at my grasshoppers! This one is named Sir Hoppy Bob. Oh no Sir Hoppy Bob don’t escape!” reverberating through the building. Well, ladies and gentlemen, you can attribute these comical events to campers of the Shultz Lab’s world-renowned Bug Camp 2018: Insects, Science, and Society. Kelly Kulhanek, Ph.D. student & Nathalie Steinhauer, Postdoc, work with NASA to look at pollinator health from space! NASA uses satellite data to reveal the environmental factors that affect honeybee populations. "This large-scale satellite data that NASA developed is really going to enable us to make large-scale correlations about the factors we’re seeing in honeybees and the physical interactions they are having with their landscape." , said Kulhanek. NASA summarizes the project: Congratulations to UMD graduate student Veronica Johnson who successfully defended her thesis, "Understanding the effects of post-harvest litter management practices on the degradation of Bacillus thuringiensis (BT) proteins in genetically modified field corn debris" The Department of Entomology at the University of Maryland, invites applications for a Post Doctoral Associate in Community Ecology of Forest Arthropods.
The incumbent will work with Dr. Daniel Gruner on several projects with theoretical and applied foci: (1) Community-level biological control by natural enemies of the emerald ash borer in mid-Atlantic states, and (2) Spatio-temporal drivers of arthropod diversity on a chronosequence of forested sites in the Hawaiian Islands. The interdisciplinary nature of this research will provide opportunities for the postdoc to work with collaborators from the USDA Agricultural Research Service, the US Forest Service, and the University of California-Berkeley, among others. Click here for the complete Job Announcement. A wet and stormy spring and summer has contributed to a rise in the mosquito population. In response, MPT News airs expert advice from UMD Entomology professor, Michael Raupp, on ways to prevent mosquito bites. The Ruth Patrick Award is given to scientists who have made outstanding contributions towards solving environmental problems. The Association for the Sciences of Limnology & Oceanography (ASLO) has awarded Dr. Margaret Palmer of the University of Maryland, College Park this distinguished honor in recognition for being a champion of solution-driven science for the protection of freshwaters. The award will be presented at the ASLO Summer Meeting in Victoria, British Columbia in June 2018. Congratulations Dr. Palmer! Read the full press release here. Congratulations to Dilip Venugopal and Galen Divley on their publication released today in Royal Society Open Science! Climate change, transgenic corn adoption and field-evolved resistance in corn earworm. Pests aggravate the agricultural costs of climate change. Understanding climate change interaction with transgenic crops, a key insect pest management strategy, helps minimize agricultural losses. We found that increasing temperature anomaly and its interaction with high Bt acreage probably accelerated Bt resistance development in a major crop pest, corn earworm. Bt resistant corn earworms may spread further given extensive Bt adoption, and their range expansion due to climate change. We highlight the need to incorporate evolutionary processes affected by climate change into Bt resistance management programs, and the challenges posed by climate change for Bt biotechnology based insect pest management. Check out the full article here. Dilip Venugopal completed his Ph.D. in the Entomology Department in 2014, co-advised by Drs. William Lamp and Galen Dively. He is now a AAAS Science & Technology Fellow at the Environmental Protection Agency in Washington, D.C.
Transgenic Bt crops have been a very successful tool for managing various insect pests in field crops. However, like all pest management strategies, they have both pros and cons. Dr. Dominic Reisig, from North Carolina State University, discusses the challenges of managing resistance against Bt crops, using the example of Helicoverpa zea, an important pest of both corn and cotton.
The mechanisms of exactly how mosquitoes locate their human hosts still elude the scientific community. Dr Conor McMeniman’s lab at Johns Hopkins has made advances in understanding the important role that the CO2 we exhale has to play in mosquitoes’ host-finding abilities. With the urgency of the Zika threat looming, understanding its mosquito vectors’ human-finding processes is vital to public health.
Ph.D. student, Samuel Ramsey of the vanEngelsdorp Lab took 1st place in the 4th annual 3MT competition on April 5, 2017. After much preparation and making it through the first round of competitions the week prior, he scored the top prize!
Sammy will be awarded $500 and will go on to represent UMD in the International competition in October. Here is some info on the background of the competition but without the winners for this year updated on the site. Please offer him congratulations when you see him. We are very proud! Natural threats among the flowers lurk. Dr. T'ai Roulston delves into the somewhat macabre world of bumble bee parasitism by conopid or thick-headed flies.
"Dr. Arnaud Martin details his research adapting the CRISPR-Cas9 gene editing system to crustaceans and butterflies, providing further evidence that supports previous findings surrounding the use of genetic tool kits found in all animals."
Ear damage? In this case, we are not talking about listening to music too loud or standing too close to the speakers at a rock concert. Instead, Dr. Galen Dively, Professor Emeritus in the Department of Entomology, has unlocked the mystery shrouding the increased dmanage to ears of corn. Read more about Dively's study here.
Post-doc Christopher Taylor (Hamby Lab), graduate student Veronica Johnson (Hooks Lab), and Professor Emeritus Dr. Galen Dively have a new publication titled, "Assessing the use of antimicrobials to sterilize brown marmorated stink bug egg masses and prevent symbiont acquisition" in Journal of Pest Science. You can read the abstract below and find the full feature here. Congratulations on your achievement!
Dr. Dennis vanEngelsdorp is one of two college employees named to Clarivate Analytics' 2016 list of Highly Cited Researchers (HCR). HCR is a comprehensive list of influential individuals in various scientific disciplines. More on the announcement can be found on the College of Computer, Mathematical, and Natural Sciences (CMNS) home page.
However, asymptomatic bees are common and can have either low or high virus loads (de Miranda et al. 2012). The story is complicated by the fact that DWV is very closely related to a series of other RNA viruses, such as Varroa destructor virus-1 (VDV-1). And the story gets even more complicated… because of recombination.
Using next generation gene sequencing, Dr. Ryabov (currently a visiting scientist at the United States Department of Agriculture (USDA) Bee Research Lab in Beltsville, MD) and his colleagues at the University of Warwick, UK, decided to characterize the virus diversity in honey bees. They found that the genome of DWV-like viruses could be divided into three functional parts, or “modules”, any of which were sometimes crossed-over between DWV and VDV. They identified three distinct types of genomes: the 100% DWV genome, and two types of recombinants formed by the association of “modules” from DWV and VDV, which they named VDV-1DVD and VDV-1VVD (Moore et al. 2011). So what was thought to be a single population of viruses is actually a group of variants (VDV-1DVD, VDV-1VVD and DWV). Dr. Ryabov then compared the levels of each variant in honey bee pupae and associated Varroa mites. They found that individual honey bees were usually infected by a mixture of the three variants. Of the three viruses, the recombinant VDV-1DVD’s levels in honey bee pupae was highly associated with its level in associated mites. This suggests this recombinant is more efficiently transmitted between the mite and the honey bee. When Varroa acts as a vector for the DWV, it increases the levels of viruses in contaminated colonies, causes deformities in the affected workers (Fig. 2), and overall results in increased risk of mortality of the whole colony. But what remains to be determined is whether this is caused by 1) Varroa amplifying and introducing more virulent strains of the virus and/or by 2) Varroa suppressing the honey bee immune response. To test those two hypotheses, Dr. Ryabov exposed Varroa-naïve honey bees (collected from a Varroa-free region in Scotland) to DWV either orally (in brood food) or through Varroa mite feeding. They monitored the change in DWV diversity and loads within the host as well as changes in honey bee expressed genes to identify potential antivirus immune responses (Ryabov et al. 2014). They detected changes in expression for a number of genes associated with the immune response of honey bees while in presence of the mites. This suggests that the second hypothesis should be further explored. This study also showed that in Varroa-free colonies (controls), honey bees had highly diverse DWV, though at low levels. When the bees were infected orally, DWV levels remained low, but the composition of the DWV strains changed compared to the controls. When bees were infected through Varroa, two outcomes would happen. Honey bees either showed low levels of diverse DWV strains, or they developed high levels of a single specific variant of DWV or very closely related variants, even though the infecting mite contained a high diversity of strains. By inoculating honey bees through injections (which simulates Varroa feeding), the researchers observed high levels of replication for the recombinant strains containing VDV-1 derived structural gene block. This suggests that these particular strains have an advantage due to the route of transmission. All of this largely supports the first hypothesis that Varroa amplifies more virulent strains of the virus. In conclusion, this example of the shift in virulence of the DWV – from a benign and asymptomatic virus to a serious disease – illustrates the importance of the process of recombination in the generation of various strains of viruses, and how the addition of a vector, and a new route of transmission, can increase the impact of a virus by altering the relative composition of its strains. Bloggers: Meghan McConnell is a Master’s student in Dennis vanEngelsdorp’s Lab. She is currently studying honey bees, with a focus on non-chemical control of Varroa mites. Nathalie Steinhauer is a PhD candidate working in Dennis vanEngelsdorp’s Lab on honey bee health and management practices. Her projects aims to identify and quantify the effects of risk factors associated with increased colony mortality. References: Bowen-Walker, P. L., S. J. Martin, & A. Gunn. 1999. The Transmission of Deformed Wing Virus between Honeybees (Apis mellifera L.) by the Ectoparasitic Mite Varroa jacobsoni Oud. Journal of invertebrate pathology 73(1), 101-106. Highfield, A. C., A., El Nagar, L. C. Mackinde, M. L. N. Laure, M. J. Hall, S. J. Martin, & D. C. Schroeder. 2009. Deformed wing virus implicated in overwintering honeybee colony losses. Applied and environmental microbiology 75(22), 7212-7220. de Miranda, J. R., L. Gauthier, M. Ribiere, and Y. P. Chen. 2012. Honey bee viruses and their effect on bee and colony health. In D. Sammataro & J. Yoder (Eds.) Honey bee colony health: challenges and sustainable solutions. CRC Press. Boca Raton. 71-102. Moore, J; Jironkin, A; Chandler, D; Burroughs, N; Evans, DJ; Ryabov, EV (2011) Recombinants between Deformed wing virus and Varroa destructor virus-1 may prevail in Varroa destructor-infested honeybee colonies. Journal of General Virology, 92(1): 156–161. DOI:10.1099/vir.0.025965-0 Ryabov, EV; Wood, GR; Fannon, JM; Moore, JD; Bull, JC; Chandler, D; Mead, A; Burroughs, N; Evans, DJ (2014) A Virulent Strain of Deformed Wing Virus (DWV) of Honeybees (Apis mellifera) Prevails after Varroa destructor-Mediated, or In Vitro, Transmission. PLoS Pathogens, 10(6): 1–21. DOI:10.1371/journal.ppat.1004230 Aliens are invading the forests of the United States! Not the green, bug-eyed aliens from outer space; no we are talking about the, well… green, bug-eyed aliens from Earth. With the globalization of trade, insect introductions leading to invasive pest problems have steadily increased over the last few centuries, causing massive economic and environmental devastation in the systems where these pests permeate. These invaders are especially difficult to manage when they are pests of our native North American forest trees due to the large spatial scale associated with them, making pesticide applications impractical.
having a warmer climate than Connecticut, created an asynchronous relationship between the host (EHS) and the parasitoid (E. citrina) in Connecticut. This means that the scale and parasitoid are developing at different times of year, preventing the wasp from being able to effectively attack the scale in its introduced range. With the colder climate of Connecticut, it was hypothesized that the EHS scales developed more slowly. Wasps, as a result, would have fewer suitable 2nd instar hosts to parasitize. Dr. Abell tested this by observing scale abundance and parasitism by E. citrina at three distinct latitudes in the U.S. (Connecticut [“coldest”], Pennsylvania, North Carolina [“warmest”]), hypothesizing that he would find more parasitoid-host synchrony as he moved further south where warmer temperatures would allow for multiple generations of scales. Ultimately, Dr. Abell did not observe any increase in synchrony between EHS and E. citrina at any of his three field sites. Instead he found continuous reproduction of EHS, and all life stages were present throughout the year. This led Dr. Abell to Japan to better understand how EHS behaves in its native range. While surveying hemlock scales and their associated parasitoids, Dr. Abell found 11 new species attacking EHS in Japan, some of which may have potential as classical biological control agents.
a wasp that is less than 1mm in length that attacks EAB eggs. Research done by Duan et al. in 2013 indicated that T. planipennisi was effectively established in Michigan and is a strong disperser. However, they observed that there was no parasitism of EAB in larger trees. In a study done by Dr. Abell, it was determined that the bark thickness was preventing this small wasp from attacking the EAB larvae. The ovipositor (egg-laying mechanism) of T. planipennisi is too short to reach the EAB larvae underneath the thick bark.
The bark was also placed in emergence chambers to collect any parasitoid wasps that emerged from the bark remnants that were missed in earlier screening. After two years of testing these methods, Dr. Abell concluded that the bark-sifting method was a more effective way to measure the rate of O. agrili egg parasitism in the field because significantly more parasitoids were recovered with this method. Invasive insects continue to attack our forests today, therefore it is very important to continue to understand and utilize biological control methods to preserve our forests. Dr. Abell continues his work on EAB biological control in the Shrewsbury lab here at the University of Maryland where he is evaluating other introduced and native parasitoids and additionally an integrated approach that combines pesticides with classical biological control methods.
About the Authors: Olivia Bernauer is a second year Master’s student in Dennis vanEngelsdorp’s bee lab working to better understand the floral preferences of Maryland’s wild, native pollinators. Jackie Hoban is a second year Master’s student working on emerald ash borer biological control in Paula Shrewsbury’s lab. |
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