Eidgenössisches Departement für Wirtschaft, Bildung und Forschung WBF
Agroscope
Drosophila suzukii:
Local infestation patterns and monitoring
around Wädenswil
• Local history of D. suzukii appearance in Wädenswil
• Setup of a local monitoring 2012
• Occurrence and distribution
• Additional findings
• Open questions
• Adaptations for 2013
Content
CH 2011
first observations
Wädenswil
Swiss D. suzukii monitoring 2012
First records ZH:
Week 29 + 31: 1♂ each (in raspberries)
Wädenswil
Schweiz 2012
Wädenswil
Damage on
blackberries
Local monitoring
Official
monitoring trap 2012
0,5 L PET Monitoring
Extended monitoring and experiments with baits
Mass trapping
Commercial Gasser trap
Apple vinegar + water [1:1]
Vinegar, red wine, sugars,
Crops considered
Mai Jun Jul Aug Sep Okt Nov Early
season
Main season
End
season
Alternative hosts
Situation Wädenswil 2012
Official monitoring traps (in cherries)
Au, Horgen May to mid July:
NO CAPTURES
Situation Wädenswil 2012
First captures
(in blackberries)
Mid to end of July:
2 males
Situation Wädenswil 2012
Increasing captures
(in raspberries & blackberries)
August:
> 500 flies
(mass trapping installed)
Situation Wädenswil 2012
Captures in:
Raspberries, blackberries,
elderberries, prunes, compost, grapes, etc.
ACW
SEP + OCT:
CAPTURES in all
monitoring and
additional traps
Situation Wädenswil 2012
Captures in:
Raspberry, blackberry, wild berries, elder,
prune, compost, grape, etc.
ACW
NOVEMBER:
Decreasing
CAPTURES
Situation Wädenswil 2012
DECEMBER:
Very few
CAPTURES
Seasonal captures in Wädenswil
Mai Jun Jul Aug Sep Okt Nov
Captures
Early season
Main season
End season Alternative
hosts
Results
Additional findings Wädenswil 2012
D. suzukii captures in different crops (flies/trap/week)
Elder berries Prunes
Wild berries, grapes
Raspberries ZHAW
Raspberries (on farm)
Grapes
50 100 150 200
M itte l p ro Falle 2 0 1 2
Männchen
Weibchen
Females Males
Additional findings Wädenswil 2012
D. suzukii captures+ sex ratio in different crops
0%
25%
50%
75%
100%
Weibchen Männchen
Females Males
Additional findings Wädenswil 2012
D. suzukii sex ratio in different crops
Summary
• No captures in early summer (sweet cherries)
• First captures in rasp- & blackberries
• Dispersal into stone fruits, berries, grapes and wild hosts
• Damage only in blackberries
• Post harvest appearance in prunes and cherries
• No accumulation in vineyards at late season
Some open questions
• Where did flies come from in early season?
• Preferred habitats/crops?
• Preconditions for damage?
• Relationship between captures and infestation?
• Post-harvest dynamics?
• Colonisation of overwintering sites?
• Seasonal response to attractants/baits?
Adaptations for 2013
• Additional habitats
• All-season monitoring
• Including yeast baits
3 4
5 2
1 11
9 10
12
6 8
7
Monitoring traps 2013
1. Compost
2. Sweet cherries 3. Raspberries 4. Elder
5. Edge of forest new!
6. Forest new!
7. Apple new!
8. Blackberry 9. Plum, prune 10. Grapes 11. Prune
12. Wild shrubs (park) new!
Aims:
More information about overwintering sites, local occurrence, seasonal distribution and
Additional habitats
Adaptations for 2013
• Additional habitats
• All-season monitoring
• Including yeast baits
All-season monitoring
Date males females
07.01.2013 31 56
21.01.2013 0 0
04.02.2013 0 2
19.02.2013 0 0
04.03.2013 0 0
18.03.2013 0 0
25.03.2013 0 0
Actual situation in Wädenswil
(24 monitoring traps in different habitats)
Trap examination:
NOV-MAR: 2x per month
APR-OCT: weekly
Adaptations for 2013
• Additional habitats
• All-season monitoring
• Including yeast baits
Yeast experiment 2012
0.0 2.0 4.0 6.0 8.0 10.0 12.0
Essig Apfelsaft + Essig S. cerivisae + Apfelsaft + Essig H. uvarum + Apfelsaft + Essig Ethanol + S. cerivisiae + Apfelsaft + Essig Ethanol + H. uvarum + Apfelsaft + Essig Gasser-Mix
Durchschnitt Fliegen / Falle
0 5 10 15 20 25
M MA HUT CVT G
HUT PLUS CVT PLUS New batch of
yeast bait
