What Did We learn This Year About Spotted Wing Drosophila?

Professor Donn T. Johnson

and Barbara Lewis

Department of Entomology

SWD Information: http://comp.uark.edu/~dtjohnso/

Updated as needed

HANDOUT

% of unsprayed ripe fruit infested by SWD in Arkansas

Ripe Fruit 2013* 2014*

Raspberry 48% 100%

‘Wye’ berry - 100%

Blackberry 30% 100%

Wild Blackberry - 100%

Nectarine -Many fruit with

lesions

Peach Low (lesion or crack) Low (lesion or crack)

Blueberry low low

Strawberry Low Low (late June)

Grape Low (lesion or crack) Low (lesion or crack)

* Get close to 0% SWD infested ripe fruit with weekly insecticide applications during ripening to harvest

SWD Infestation in Commercial Raspberries and Blackberries in Springdale (2014)

Mustang Max applied 17 JulyMostly eggs on fruit

Date # Fruit # Infested % SWD

6/4/2014 30 RB 0 0

6/9/2014 30 R 0 0

6/10/2014 30 R 2 6.7

6/18/2014 30 R 0 0

7/1/2014 30 R 7 23.3

7/8/2014 27 B 25 92.6

7/14/2014

7/21/14 30 B 30 100.0

7/28/14 30 B 37.9

R = raspberry; B = blackberry

Fruit Attacked by SWD in AR

SWD Larvae on Wild Blackberry

SWD Eggs on Blackberry

SWD Eggs/Larvae on Nectarine (may be bacterial spot lesions)

SWD Eggs on Raspberry and Wye berry

D. melanogaster egg

SWD egg

11 July 2014 - SWD found in wild blackberries in clam shell

SWD Infestation of Commercial or Wild Blackberries

• Ripe blackberries > 11 % Brix = 100% infested

• Ripening blackberries = 9.4 % Brix = < 13% infested

• Unripe to green = < 7% Brix = 0% infested

Springdale, AR 2014 ripe ripening unripe

12-Jul 100

14-Jul 100 13.3 0

21-Jul 80 6.7 0

28-Jul 50

4-Aug 93

11-Aug 95

% SWD infested wild blackberry

Summary of SWD Knowledge(eFly, WERA1021 SWD Working Group Meetings)

• Fruit infestations in Fayetteville, AR:• 1 July (Fayetteville)= 23% SWD raspberries

• From 8 July to 12 Aug. = > 83% SWD infested blackberries

– Fruit infestations in Clarksville, AR:

• 21 July = 93% SWD blackberries

• From 21 July to 25 Aug. = > 72% SWD infested fruit

• Pick daily, refrigerate fruit immediately and keep cold until processed or eaten

– 2-3 days at 34⁰F kills SWD eggs and small larvae

SWD Workshops & Updates at State and Regional Grower Meetings

• 2013

– March and April 2013 – 3 Extension Agent/grower workshops

• 2014

– 10 January - OK/AR Horticulture Industry Show

– 6 February - Missouri Organic Association

– 8 February - Alabama Fruit and Vegetable Growers Conference

– 28 February - Mid America Strawberry Grower Conference

– 4 March - SE Branch Entomological Society of America meeting

– 27 March - Organic High Tunnel Strawberry Production

– 31 July – Fayetteville Farmers’ Market vendors

• 2015– 16-17 January - OK/AR Horticulture Industry Show

– 29 January – 6th Mid-South Commercial Horticulture-- Fruit Producers Meeting in Conway, AR

Output of DD Model for Searcy, AR (2014)

http://uspest.org/cgi-bin/ddmodel.us?sta=KSRC

5 generations by 1 Sept.

• Predict: 1st generation fly peak emergence by 19 May, 1st to 4th gen. peak egg laying by 28 May, 17 June, 4 & 23 July

• Traps caught 1st SWD on 27 May in Searcy and on 17 June in Fayetteville with damage by 24 June

Management of SWD1. Thin or open up canopy to improve spray coverage

2. Monitor traps weekly for SWD flies starting 3 wks before ripening

3. Spray if SWD found and fruit are ripening, apply recommended insecticide every 5 to 7 days (re-apply after 1” rain) and rotate mode of action to delay resistance development in SWD

4. Evaluate spray effectiveness = look for SWD eggs/larvae in fruit

5. Exclude SWD using screen or row cover (mesh < 1 mm holes)

6. Pick daily, refrigerate fruit immediately and keep cold until processed or eaten (2-3 days at 34⁰F kills SWD eggs and larvae)

7. Sanitation: pick leftover or damaged fruit and solarize in black bags to reduce SWD food source

8. Stay informed – visit SWD web sites and attend grower meetings

Informative SWD Web sites

http://spottedwing.org/

http://swd.ces.ncsu.edu/

http://www.ipm.msu.edu/invasive_species/spotted_wing_drosophila

Fill Out 2014 SWD Impact Survey (Handout)http://swd.ces.ncsu.edu/2014/12/measuring-the-impacts-of-spotted-wing-drosophila-

in-2014-your-help-needed/

• Participation in the survey is voluntary.

• Please fill in survey and mail back ASAP

• The purpose of this survey is to collect information measuring the impact of SWD on agricultural production.

• The responses will be used to prioritize research, extension, and education activities for SWD.

• Survey data may be summarized by state, crop, farm size, or farm type.

• Results will be available in mid March 2015 at: swd.ces.ncsu.edu

• Ask questions about this survey by contacting Dr. Hannah Burrack(hjburrac@ncsu.edu or 919.513.4344)

2014 Research/Extension Working Groups on SWD

• Mission: to develop sustainable SWD management strategies

– January - eFLY SWD Working Group

– October - planning meeting and subsequent conference calls to develop a proposal on Organic Management of SWD

– November

• WERA1021 Spotted Wing Drosophila Biology, Ecology, and Management

• 2 symposia on SWD at the Entomological Society of America meeting

Summary of SWD Knowledge(eFly, WERA1021 SWD Working Group Meetings)

• SWD preference:

– Given a choice, SWD lay more eggs in cultivated blackberry than blueberry or wild blackberries (Liburd; FL)

– High risk for SWD fruit infestations: blackberries, primocane-fruiting blackberries and raspberries and day neutral strawberries

• Other SWD hosts:

– Wild plum, wild cherry, night shade, wild blackberry, holly, sparkleberry, poke weed

• SWD infestations are higher on fruit in lower canopy

• Yeast or Trécé lure baited traps captured 1st SWD 1 wk before 1st

infested berry detected (Johnson, AR; Loeb, NY)

• For every 8 SWD flies in traps, there are at least 92 SWD eggs, larvae of pupae in fruit

Summary of SWD Knowledge(eFly, WERA1021 SWD Working Group Meetings)

• > 40% more insecticide applications are being used compared to before SWD appeared (NJ)

• 5 to 7 day insecticide spray program with a registered product

• Efficacy of different insecticides

– Spray coverage is vital

– Conventional insecticides gave > 3 day kill

• Malathion, Delegate, Mustang Max and Entrust are effective

– OMRI insecticides gave < 3 day kill

• Pyganic (poor to fair efficacy – degrades in 1 day)

Knowledge Needed on SWD(eFly, WERA1021 SWD Working Group Meetings)

• Yet to determine:

– If/where SWD overwinters

– How SWD disperse into fruit plantings

– Time of day & how long flies spend resting, dispersing to new habitat, mating, feeding and laying eggs

• What time of day best to apply short residual sprays

• Where to direct sprays on part of plant most frequented by SWD

Summary of SWD Knowledge(eFly, WERA1021 SWD Working Group Meetings)

• Six issues of AR Fruit & Nut News were disseminated to County Agents, growers and available online:http://comp.uark.edu/~dtjohnso/Arkansas_Fruit_Newsletter.html

What Makes Trap Attractive to SWD?

• Visual Cues:

– Vertical bands of Red / Yellow > Black > White > Clear

• Place holes just above bait solution

• Large entry area (2mm mesh siding or large number of holes) will bring in higher numbers of SWD; too large a screen area will allow for to much evaporation

Amy J. Dreves, Oregon State University

Changes in SWD Monitoring Traps

2014 Several Effective Trap Designs

2012 trap

2013 traps

Summary of SWD Knowledge(eFly, WERA1021 SWD Working Group Meetings)

2 liter inverted bottle trap is better than the red or clear cup traps

• It cost < $0.10/trap, is easy to make

• Opening is at the bottom of the trap

• Use with insecticide & sugar baited sprays or attract-and-kill program

Red cup trap, two bottle traps, yellow Trappit trap, and screen trap (Left photo: Cowles Right photo: Johnson)

http://www.northeastipm.org/about-us/publications/ipm-insights/how-to-trap-spotted-wing-drosophila/

Making the Bottle Trap

Best SWD Bait(eFly, WERA1021 SWD Working Group Meetings)

Yeast bait is slightly better than Trécé dual SWD lure (Michigan) and slightly better than 11% ethanol spiked grape juice + ACV:

• Yeast bait = 32 oz water + 2 tbsp yeast + 4 tbsp sugar

– Ferment for a day, then transfer 4 fl oz to trap

– Sieve out flies and change solution weekly

• Trécé SWD dual lures held over apple cider vinegar (ACV) changed monthly

• Sieve out flies weekly

• 11% ethanol spiked grape juice + ACV

• Place traps at fruit height at end of row with ripening fruit nearest woodlot

Compare Trécé AB Dual Lures to Yeast Ferment Lure in Commercial Blackberries in Judsonia, AR (2014)

2014 SWD Trap Placement, Bait & Collecting SWD Flies

Trécé SWD dual lures more attractive than Concord grape juice + apple cider vinegar spiked to

11% ethanol (NW Arkansas 2014)

Trécé

Ferment = 11% EtOH spiked grapejuice + ACV

SWD in Berries in NW AR1st SWD flies on 24 June; > 40 SWD/trap from 8 July to 12 Aug.,

and peak of 126 or 34 SWD/trap on 15 July (two sprays applied = )

Malathion

Mustang Max

92%

40%

100%34% 83%

100%

Mustang Max

23%

0%

Tontitown had 33% SWD infested blackberries on 14 July, then sprayed weekly = < 5% infested berries through 18 Aug.; Springdale had 23% SWD infested raspberries on 24 June, > 83% SWD infested black berries from 8 July to 12 Aug., 2 sprays 40% & 34%

SWD in Fruit Station in Clarksville, AR1st SWD flies on 14 July; > 20 SWD/trap from 21 July to 18 Aug.,

Peak of 160 SWD/trap on 28 July (sprayed weekly mid-July to Sept.)

Unsprayed blackberries had “0” infested until 21 July and > 72% SWD infested berries from 21 July to 25 Aug. Weekly sprayed blackberries had from 16 to 45% infested berries

93%88%

92%

72%

40%45% 20% 16%

Summary of SWD Knowledge(eFly, WERA1021 SWD Working Group Meetings)

• Netting has been effective in excluding SWD in Arkansas, Quebec and in New York

• Attract & Kill: attractants lure SWD to insecticide bait –promising if used around the field to attract and kill SWD

• Mass trapping - no success so far

Proteknet 80g Exclusion Netting and Entry Door into Blueberries Exclude SWD, Birds, Mammals and Prevent Hail Damage

Dale Ila M. Riggs, The Berry Patch of Stone Wall Hill Farm, LLC in Stephentown, NY

New Liskeard, Ontario blueberries

Infested Fruit in Blueberries With and Without (Control) Exclusion

Screen

Dale Ila M. Riggs, The Berry Patch

Exclusion by Screening High Tunnel

SWD inside/outside screened high tunnel (Fayetteville, AR)

0

20

40

60

80

100

120

140

160

180

200

Outside Dual Lure + ACV

Fermt+ACV

HT (screen) Lure + ACV

No

. S

WD

flies /

bait

ed

tra

p

Emerging SWD flies from ripe blackberries in

outside planting in Fayetteville, AR (2014)

0

10

20

30

40

50

60

70

80

90

100

Females

Males

No

. em

erg

ed

SWD

flie

s

Acknowledgements

Funding:

• Southern Region Small Fruit Consortium

• USDA/SARE - Extending the market season with high tunnel technology for organic fruit production

• AR Ag. Dept. and Extension IPM-SCBGP: Spotted wing drosophila

Acknowledgements

Cooperators:

Co-PIs: Elena Garcia, Curt Rom, John Clark, Jackie Lee, Eric Stafne

Barbara Lewis, Sam Kim, Clint Trammel, Jason McAfee, Luke Freeman, Heather Friedrich, Cynthia Stewart, Philip Stewart, and Kay Buck (UA Farm in Fayetteville)

Taunya Ernst (Fruit Station in Clarksville)

Clay Wingfield & Jessica Lefors (SWREC, Hempstead & Howard Co.)

14 AR County Extension agents Especially Sherri Sanders, Dustin Blakey, Carey Wall, Berni Kurz, Cindy Ham,

Bob Rhodes and Carey Wall

Berry growers: Pat Ford, Les Dozier, Marlin Wallace, David Dickey