Drosophila suzukii Studies Marissa Diorio Dr. Fingerut Elizabeth Krohn Thomas Smith Stephanie Tittaferrante Dr. McRobert
Drosophila suzukii Studies
Marissa Diorio
Dr. Fingerut
Elizabeth KrohnThomas SmithStephanie Tittaferrante
Dr. McRobert
Our ObjectivesDr. McRobert’s Lab:● Blueberry Fecundity
Study○ In Progress
● Remating Study○ Starting Soon
● Hybridization Study with D. biarmipes
Dr. Fingerut’s Lab:● Overwintering Study
○ In Progress○ Gauging lower lethal
temperature○ Construction of a mesocosm
Invasive Species● Southeast Asia -> global trade -> Hawaii, California, USA, Canada,
Europe● Climate prefer warm, temperate climate, but adaptable and resilient
http://ncsmallfruitsipm.blogspot.com/2013/02/spotted-wing-drosophila-confirmed-from.htmlhttp://labs.russell.wisc.edu/swd/
The threathttp://entnemdept.ufl.edu/creatures/fruit/flies/drosophila_suzukii.htmhttp://www.enetpress.com/drosophila/swd_index.html http://www.virginiafruit.ento.vt.edu/SWD.htmlhttp://entnemdept.ufl.edu/creatures/fruit/flies/drosophila_suzukii.htm
The threat● Hundreds of offspring
http://whatcom.wsu.edu/ipm/manual/black/spotted_wing.html http://entnemdept.ufl.edu/creatures/fruit/flies/drosophila_suzukii.html
● Rapid life cycle
Suzukii’s late appearance● Seem to disappear over winter and
then re-emerge in late summer● Other species re-emerge in April● What causes this disappearance?
o How can we utilize it?
Overwintering● Winter knocks down the population● How are they repopulating?
○ Migration○ A few survive in nature○ A few survive in structures
Chill Study● Room temperature vs. Chilled
○ measure of adult survivorship○ measure of time to pupation○ measure of time to eclosure
● Stunted reproduction
Further research● Construction of a mesocosm ● Observation of reproductive
physiology as the weather changeso if surviving, where and in what life stage?
● Hope to find evidence to explain disappearance
Technique Notes● Population boxes
● Traps
The Blueberry Study● Blueberries in D. suzukii
reproduction studieso 4 different conditions (20
offspring producing flies each)1. Blueberry / Blueberry2. Blueberry / No blueberry3. No blueberry / No
blueberry4. No Blueberry / Blueberry
The Blueberry Study - Step 1● Collection
o Within 6 hourso Juveniles
Pale, large● Housing
o Males - 1/vial Media + yeast
o Females - 1/vial Media + yeast Media + yeast + blueberry
The Blueberry Study - Step 2
● Experimental Assayso Testing 3-5 days oldo Transfer 1 male and 1
female to a vial No blueberry
o Observe flies - 60 min Copulation latency Copulation duration
D. suzukii courtship
The Blueberry Study - Step 3● After the experimental
assay…o Transfer mated female
Vial = Media + yeast Vial = Media + yeast +
blueberry
The Blueberry Study - Step 4● 7 days later…sucrose extraction
o Count offspring:1. Eggs2. Larvae3. Pupal cases
Copulation Frequency
Copulation Latency and Duration
Offspring Production
Technique Notes for D. Suzukii● Paper towel & Moisture
○ Pupal case growth● Blueberry/Yeast Food
○ True fruit fly● Contamination Hazards
○ Bottles vs. Vials○ Cotton Balls vs. Foam Stoppers
Cotton Ball Contamination Pictures
Stage One: Growth of pupal cases on cotton ball
Stage Two: Pupal cases expand and cause more gaps
Stage Three: Flies hatch and cause even more space in cotton ball
Stage Four: Flies find enough space to escape and/or enter vial
Individual Fly Study● Work with individuals, not mass
quantities● Specific Equipment:
○ Dissecting Scope and Light○ CO2 Pad and Funnel○ Mouth Aspirator (Suck Tube)○ Paintbrushes
Conclusions: Why These Studies Matter
● Economic losses:o Yield losseso Increased laboro Increased chemical input costso Loss of foreign markets
● Loss of 20% of blueberry crops - $56.7 million - CA, OR, WA
● Current management - adult flies
Thank you Sponsors● Saint Joseph’s Summer Scholars Program● Dr. Scott McRobert● Dr. Jonathan Fingerut● McNulty Fellows Program● SJU Biology Department● Also, a thank you to students who
previously worked on this project○ Kristina Orbe ‘14○ Leigh Anne Tiffany ‘15