As part of a continuing series of Canadian Entomology Research Roundups, here’s what some Canadian entomology grad students have been up to lately:
From the authors:
Finn Hamilton (University of Victoria)
It is now well known that the majority of insects host symbiotic bacteria that have profound consequences for host biology. In some cases, these symbioses can protect hosts against virulent parasites and pathogens, although in most cases it remains unclear how symbionts achieve this defense. In this paper, we show that a strain of the bacterium Spiroplasma that protects its Drosophila host against a virulent nematode parasite encodes a protein toxin. This toxin appears to attack the nematode host during Spiroplasma-mediated defense, representing one of the clearest demonstrations to date of mechanisms underpinning insect defensive symbiosis. Article link
Lucas Roscoe (University of Toronto)
The Emerald Ash Borer (Agrilus planipennis Fairmaire, EAB) is a buprestid pest of ash trees in North America. As part of the development of long-term management plans for EAB, several projects detailing the biology and ecology of poorly-known, yet indigenous parasitoids associated with EAB were initiated. One project concerned the mating sequences of the chalcidid parasitoid, Phasgonophora sulcata Westwood. Many insects undertake repeatable actions prior to mating. These are commonly mediated by pheromones. The results of this research were the description of the mating sequence of P. sulcata, and evidence of female-produced pheromones that initiate these actions. Article link
Marla Schwarzfeld (University of Alberta)
The parasitic wasp genus Ophion (Hymenoptera: Ichneumonidae) is almost entirely unknown in the Nearctic region, with the vast majority of species undescribed. In this study, we published the first molecular phylogeny of the genus, based on COI, ITS2, and 28S gene regions. While focusing on Nearctic specimens, we also included representatives of most known species from the western Palearctic region and several sequences from other geographical regions. We delimited 13 species groups, most recognized for the first time in this study. This phylogeny will provide an essential framework that will hopefully inspire taxonomists to divide and conquer (and describe!) new species in this morphologically challenging genus. Article link
Seung-Il Lee (University of Alberta)
Seung-Il Lee and his colleagues (University of Alberta) found that large retention patches (> 3.33 ha) minimize negative edge effects on saproxylic beetle assemblages in boreal white spruce stands. Article link Blog post
Paul Abram (Université de Montréal)
The relationship between insect body size and life history traits (e.g. longevity, fecundity) has been extensively studied, but the additional effect of body size on behavioural traits is less well known. Using the egg parasitoid Telenomus podisi Ashmead (Hymenoptera: Platygastridae) and three of its stink bug host species as a model system, we showed that body size differences were associated with a change in a suite of not only life history parameters (longevity, egg load, egg size), but also several behavioural traits (walking speed, oviposition rate, host marking speed). Our results highlight how the entire phenotype (behaviour and life history) has to be considered when assessing associations between body size and fitness. Article link
Delyle Polet (University of Alberta)
Insect wings often have directional roughness elements- like hairs and scales- that shed water droplets along the grain, but why are these elements not always pointing in the same direction? We proposed that three strategies are at play. Droplets should be (1) shed away from the body, (2) shed as quickly as possible and (3) forced out of “valleys” formed between wing veins. A mathematical model combining these three strategies fits the orientation of hairs on a March fly wing (Penthetria heteroptera) quite well, and could readily be applied to other species or bioinspired materials. Article link
In-brief research summaries
Taxonomy, Systematics, and Morphology
Thomas Onuferko from the Packer Lab at York University and colleagues carried out an extensive survey of bee species in Niagara Region, Ontario. Onuferko et al. collected over 50 000 bees and discovered 30 species previously not recorded in the area. Article link
Christine Barrie and colleague report the Chloropidae flies associated with common reed (Phragmites) in Canada. Article link
Behaviour and Ecology
Blake Anderson (McMaster University) and colleagues investigates the decoupling hypothesis of social behaviour and activity in larval and adult fruit flies. Article link
Susan Anthony from the Sinclair Lab at Western University, along with Chris Buddle (McGill University), determined the Beringian pseudoscorpion can tolerate of both cold temperatures and immersion. Article link
A study by Fanny Maure (Université de Montréal) shows that the nutritional status of a host, the spotted lady beetle (Coleomegilla maculata), influences host fate and parasitoid fitness. Article link
Is connectivity the key? From the Buddle and Bennett Labs at McGill University and the James Lab at (Université de Montréal), Dorothy Maguire (McGill University) and colleagues use landscape connectivity and insect herbivory to propose a framework that examines that tradeoffs associated with ecosystem services. Article link
Alvaro Fuentealba (Université Laval) and colleague discovered that different host tree species show varying natural resistance to spruce budworm. Article link
Insect and Pest Management
Rachel Rix (Dalhousie University) et al. observed that mild insecticide stress can increase reproduction and help aphids better cope with subsequent stress. Article link
Lindsey Goudis (University of Guelph) and others found that the best way to control western bean cutworm is to apply lambda-cyhalothrin and chlorantraniliprole 4 to 18 day after 50 % egg hatch. Article link
Matthew Nunn (Acadia University) and colleague document the diversity and densities of important pest species of wild blueberries in Nova Scotia. Article link
Physiology and Genetics
Does heterozygosity improve symmetry in the Chilean bee, Xeromelissa rozeni? Margarita Miklasevskaja (York University) and colleague tested this hypothesis in their recent paper. Article link
Recent University of Alberta graduate Jasmine Janes and others explored the mating systems and fine-scale spatial genetic structure for effective management of mountain pine beetle. Article link
Also from the Sperling Lab at the University of Alberta, Julian Dupuis and Felix Sperling examined the complex interaction of hybridization and speciation. They characterized potential hybridization in a species group of swallowtail butterflies. Article link
Marina Defferrari (University of Toronto) and colleagues identified new insulin-like peptides in Rhodnius prolixus and that these peptides are involved in the metabolic homeostasis of lipids and carbohydrates. Article link
Techniques
Crystal Ernst (McGill University) and colleague sampled beetles and spiders in different northern habitats. They found that the diversity of beetles and spiders are affected by habitat and trap type. Article link
We are continuing to help publicize graduate student publications to the wider entomological community through our Research Roundup. If you published an article recently and would like it featured, e-mail us at entsoccan.students@gmail.com. You can also send us photos and short descriptions of your research, to appear in a later edition of the research roundup.
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