1. Winged victory for biology students at Canadian Entomological Society
meeting
December 04, 2015
Past Joint Annual Meetings of the Canadian
Entomological Society (CES) dealt with
themes such as “Beauty and Impact” or
“Entomology In a Changing World” but this
time, the 2015 gathering in Montréal
recognized the human impact on the natural
world with the theme “Entomology in the
Anthropocene.” This awareness of the
consequences of human activity leading to
such problems as climate change, species
invasion and the effects of pesticides on the
environment inspired four Western graduate
student researchers to delve deeper into
these problems.
The program for the meeting showed that the CES values students. The organization schedules an entire day
for each new researcher to give a ten minute talk about their work. All four Western students who participated
in the event won awards, more than any other institution.
Science Speaks provides highlights of the winning presentations.
Yeritza Bohorquez won the President Prize for Best Speaker: Agriculture for her presentation entitled,
Evaluating the effects of root exudates from buckwheat, Fagopyrum esculentum, on Agriotes sputator larvae.
Bohorquez, with the support of supervisor Jeremy McNeil, from the Department of Biology, is teasing out the
mechanisms by which buckwheat affects wireworms, the larvae of click beetles, which are a huge pest
problem in certain areas of Canada. They seem able to consume the most popular cultivated plants, so crop
rotation is of little help for controlling these pests. A pilot project in 2010 tested a number of cover crops and
found that flax, mustard and buckwheat lowered wireworm densities in the soil. The hitch was that the residual
chemicals left in the soil after the flaxseed and mustard were harvested inhibited the growth of subsequent
crops. Buckwheat didn’t have this negative side effect. Finding the compounds in buckwheat that deter
infestation could be a step towards a non­insecticidal alternative to kill off wireworms.
The President Prize for Best Speaker: Biological Control was presented to Lauren Des Marteaux for her
presentation on the effect of cold acclimation on the ion transport function and ultrastructure of the insect
hindgut.
When the days get cooler you tend to see very few insects even though the temperature remains above the
freezing point. This is because when most insects are cooled down to a critical thermal minimum temperature
they enter a reversible state of paralysis called chill coma. A member of Brent Sinclair’s lab in the Department
of Biology, Lauren Des Marteaux studies the process leading to this state to understand how the insect’s
physiological balance of water and salts is altered, in essence, how they survive the change and the cold.
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2. When insects enter the chill coma, the
physiological balance of water and salts is
upset. “What happens is that sodium and
water are removed from the blood and flood
into the [tube] of the gut. When they recover
from the coma you see the ions and water
moving back into the blood so it probably has
to do with their ability to transport ions in the
cold. And, enzymes, being temperature
sensitive, are affected,” reported
DesMarteaux. Moreover, if an insect
becomes acclimatized to cooler conditions,
the temperature at which they enter the coma
lowers as well and as Des Marteaux says,
insects become “better at maintaining ion and water homeostasis and we have no idea how that works either.
So we are trying to figure out the mechanisms of the loss of homeostasis in the cold and how cold acclimation
confers resistance to that.”
These matters are important when climate change is added to the discussion, in particular as severe cold
snaps, heat waves and a lack of snow cover become ever more common events. The dramatic fluctuations in
temperature lead to scenarios that haven’t been seen before. “How often are we entering coma and how
much is that a risk for predation? We don’t know exactly.” Des Marteaux adds. “The longer they are in coma
and the colder the temperature, the more they will accumulate injuries and suffer mortality. It is not an adaptive
thing, it is a symptom of reaching their critical thermal minimum temperature.”
Vicki Simkovic was awarded the President Prize: Best Poster for Testing for the presence of nestmate
recognition, territoriality and aggression in the eastern subterranean termite (Reticulitermes flavipes).
The eastern subterranean termite was introduced accidentally to the province of Ontario in several isolated
pockets of Toronto, Pelee Island and Point Pelee through separate events. These termites are different from
those of long established colonies found in the United States where colonies are founded by a king and a
queen and all of the workers and soldiers are the offspring from this single pair. Each US colony has a defined
territory which is aggressively defended from interloping neighbours by soldiers.
In the subterranean termite populations in Canada, the king and queen die off and several secondary
reproductives stay in the nymph form producing a lot of eggs ­ up to several thousand in a day. As a result, the
termite populations in Ontario have experienced a loss of genetic diversity and nest mate recognition and the
growth of large super colonies that we see in urban areas. To understand why, Simkovic brought different
populations of termites together to see how they interacted. She also designed experiments to determine if
colonies would intermix when they were faced with the need to share resources for a week. The colonies didn’t
tend to intermix and she noted no increase in aggression among the population either. According to Simkovic,
“It may not make sense to fight if there are costs involved such as dying or getting injured versus just sticking
to your relatives.”
The Graduate Research Travel Scholarship went to Joanna Konopka, also from the J. McNeil’s Lab, who
presented a poster depicting a technique to image live insects she co­developed with Drs. Danny Poinapen
and David Holdsworth at the Robarts Research Institute. Part of this method will be extended to Konopka’s
PhD research project in which she is investigating the host­parasitoid interaction between parasitic wasps and
an encroaching pest known as the brown marmorated stink bug (BMSB; Halyomorpha halys). In her research
work, she is employing behavioural, molecular and imaging techniques. She is carrying part of her work in
London (ON), and for other phases she has to go abroad.
The brown marmorated stink bug is originally from East Asia and has hitch­hiked mainly on shipping
containers to land in North America. “BMSB is now a major agricultural and horticultural pest in the United
States” says Konopka. “We already have established populations in Canada, and we want to address the
problem before it becomes serious.”
The biocontrol strategy would rely on the fact that when stink bugs lay egg masses on leaves, the parasitoid
wasps locate these masses, and lay a single egg within each of the host’s eggs. Ultimately, when the host’s
eggs hatch, only the parasitoid wasps emerge, and not the nymph of the pest. “However, before any biocontrol

3. efforts, potential interactions between native and introduced parasitoids exploiting brown marmorated stink
bug egg masses need to be fully investigated” says Konopka. The parasitoid wasp species of interest are
however not present in Canada and their importation is not allowed. Fortunately, Dr. Tara Gariepy, one of
Konopka’s co­supervisors at the London Research and Development Centre (ON) of Agriculture and Agri­
Food Canada (AAFC), collaborates with Dr. Tim Haye at CABI (Centre for Agriculture and Biosciences
International) in Switzerland. “This pest is also present in Switzerland, but not at damaging levels for crops yet.
Therefore, understanding the host­parasitoid interaction there would be useful for potential control of the pest
in North America” says Konopka. “We don’t have permits to work on those parasitoid species of interest here,
but in Switzerland they do.” For this purpose, the Student Travel Research Award enabled Konopka to work for
six months in Switzerland at CABI in Dr. Haye’s Lab.
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1151 Richmond Street
London, Ontario, Canada, N6A 5B7
Tel: 519­661­2111 ext. 86152
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