1

Sex Pheromones of the Blackcurrant Sawfly, Nematusolfaciens, and the Gooseberry

Sawfly, N. ribesii (Hymenoptera: Tenthredinae)

David Hall, Dudley Farman & Paul DouglasNatural Resources Institute,

University of Greenwich

Michelle Fountain, Madeleine Cannon, Janie Morton, Bethan Shaw & Jerry Cross

East Malling Research

Common and pest ofblackcurrant

Infestation is sporadic andlocalised, and damage can occurrapidly

No practical, systematicsampling methods or attendantcrop damage thresholds havebeen developed

Blackcurrant Sawfly, Nematus olfaciens

Soft Fruit Agronomists' Day, 11 February 2016

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Hymenoptera: Tenthredinae

Only other pheromone in Tenthredinae is yellow headed spruce sawfly, Pikonema alaskensis

Pheromone derived by breakdown of long-chain hydrocarbons (Bartelt et al., 1982)

Also identify (Z)-5-tetradecenol as synergist (Bartelt et al., 1983)

Blackcurrant sawfly: collection of volatiles

Soft Fruit Agronomists' Day, 11 February 2016

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Minutes0.0 2.5 5.0 7.5 10.0 12.5 15.0 17.5 20.0 22.5 25.0 27.5 30.0 32.5 35.0

Vo

lt

0.02

0.04

0.06

0.08

0.10

18.4

9

19.9

020

.00

20.2

1

21.6

521

.80

22.2

1

FIDHC16d.dat

Retention Time

Minutes0.0 2.5 5.0 7.5 10.0 12.5 15.0 17.5 20.0 22.5 25.0 27.5 30.0 32.5 35.0

Vo

lt

0.02

0.04

0.06

0.08

0.1018

.49

19.9

120

.01

20.2

2

21.6

2 21.

8122

.22

23.2

9

24.6

7

FIDHC15d.dat

Retention Time

Minutes0.0 2.5 5.0 7.5 10.0 12.5 15.0 17.5 20.0 22.5 25.0 27.5 30.0 32.5 35.0

Vo

lt

0.02

0.04

0.06

0.08

0.10

0.12

0.14

7.85

8.07

9.02

9.15

9.28

9.54

10.9

211

.61

14.9

2

17.1

9

18.4

918

.84

19.0

419

.14

19.9

120

.01

20.2

1

FIDent11.dat

Retention Time

Blackcurrant sawfly: collection of volatiles

extract male

extract female

volatiles female

Major component in volatile collections and extracts from both females and males is (Z)-9-tricosene

Smaller amounts of other saturated and unsaturated hydrocarbons

Blackcurrant sawfly: electroantennography (EAG)

Soft Fruit Agronomists' Day, 11 February 2016

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Minutes

0 2 4 6 8 10 12 14 16 18 20 22 24 26

FID

- v

olts

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

EA

G m

illiv

olts

100

105

110

115

120

125

130

135

5.46

5.60

6.28

8.93

9.05

9.72

10.1

710

.57

11.7

312

.09

15.0

3

16.6

9 18.6

5

FID2012-095-4 1 23-07-2012 14-58-51.dat

Retention Time

EAG2012-095-4 1 23-07-2012 14-58-51.dat

Retention Time

Minutes

14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.5 18.0 18.5 19.0 19.5 20.0

FID

- v

olts

0.000

0.025

0.050

0.075

0.100

0.125

0.150

0.175

0.200

EA

G m

illiv

olts

100

105

110

115

120

125

130

135

15.0

3

16.6

9

18.6

5FID2012-095-4 1 23-07-2012 14-58-51.dat

Retention Time

EAG2012-095-4 1 23-07-2012 14-58-51.dat

Retention Time

Blackcurrant sawfly: GC-EAG analyses

At least 4 consistent EAG responses from males to volatiles from females

No EAG responses to volatiles from males

No EAG response to Z9-23:H

Very small amounts! 12

3 4

Z9-23:H

Blackcurrant sawfly: GC-MS analyses

Spectrum suggest iso-propyl esters

iso-propyl (Z)-9-tetradecenoate

Soft Fruit Agronomists' Day, 11 February 2016

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(I)

(II)

(III)

Range of isopropyl esters synthesised

(Z)-7-tetradecenoate (I), (Z)-5-tetradecenoate (II) and (Z)-7-hexadecenoate (III) esters have same GC retention times on polar and non-polar columns

Blackcurrant sawfly: EAG-active compounds

Minutes14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.5 18.0 18.5 19.0 19.5 20.0

FID

- v

olts

0.00

0.05

0.10

0.15

0.20

0.25

EA

G m

illiv

olts

110.0

112.5

115.0

117.5

120.0

122.5

125.0

127.5

130.0FID2012-095-4 1 23-07-2012 14-58-51.dat

EAG2012-095-4 1 23-07-2012 14-58-51.dat

1

2

3 4

Synthetic compounds have similar EAG activity to components in volatile collections

Minutes14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.5 18.0 18.5 19.0 19.5 20.0

FID

- v

olts

0.005

0.010

0.015

0.020

0.025

0.030

0.035

0.040

EA

G m

illiv

olts

80

90

100

110

120

130

FID33 sawfly blend 2.dat

EAG33 sawfly blend 2.dat

II

I

III

Blackcurrant sawfly: EAG-active compounds

natural

synthetic

Soft Fruit Agronomists' Day, 11 February 2016

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Minutes8 9 10 11 12 13 14 15 16 17 18

FID

- v

olts

0.01

0.02

0.03

0.04

0.05

EA

G m

illiv

olts

40

50

60

70

80

90

100

110

120

130FID49 alds 3.dat

EAG49 alds 3.dat

Blackcurrant sawfly no EAG response to aldehydes, potential breakdown products of long-chain unsaturated hydrocarbons

nonanaldecanal

(E,Z)-2,6-nonadienal IZ9-14:Ac

Blackcurrant sawfly: EAG-active compounds

Blackcurrant sawfly: female-baited traps

Soft Fruit Agronomists' Day, 11 February 2016

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Blackcurrant sawfly: field testing 2013

0

5

10

15

20

25

Me

an t

otal

cat

ch (

±SE

)

Red Delta

Red Delta Window

a

bcb

c c c

A

ABAB

BB

BC

0

10

20

30

40

Mea

n To

tal C

atch

(±S

E)

a

bbb

b

Z5-14:iPr not necessary?

Addition of Z9-23:H greatly increases catches

Blackcurrant sawfly: field testing 2014

Soft Fruit Agronomists' Day, 11 February 2016

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0

2

4

6

8

10

A. 1mg Z7‐14iPr + 0.5 mgZ7‐16iPr (no

colour)

B. 1 mg Z7‐14iPr + 0.5 mgZ7‐16iPr + 5 mgZ9‐23H (black)

C. 0.1 mg Z7‐14iPr + 0.05 mgZ7‐16iPr (red)

D. 0.1 mg Z7‐14iPr + 0.05 mgZ7‐16iPr + 0.5mg Z9‐23H(blue)

unbaited

Mean total catch ±SE

Red delta trap

Green delta trap

Combineda

bb

b b

3-component Z7-14:iPr + Z7-16:iPr + Z9-23:H at 1 mg most attractive

Blackcurrant sawfly: field testing 2015

Blackcurrant sawfly: Conclusions

Male and female blackcurrant sawfly produce similar hydrocarbon blend, main component Z9-23:H

But hydrocarbons not EAG-active or attractive in field

Potential breakdown products not EAG-active

Pheromone components seem to be iso-propyl esters, Z5-14:iPr, Z7-14:iPr, Z7-16:iPr

Highly EAG-active and attractive in field tests

Z9-23:H synergises attractiveness of iso-propyl esters

3-component blend Z7-14:iPr + Z7-16:iPr + Z9-23:H in vials most attractive

Soft Fruit Agronomists' Day, 11 February 2016

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Gooseberry sawfly, Nematus ribesii

Common gooseberry sawfly, Nematus ribesii, sporadic, localised and unpredictable pest of gooseberry

Also lesser attacks on red and white currant

Presence of female sex pheromone attracting males already reported (1980)

Gooseberry sawfly: pheromone collection

GC-MS analysis very similar hydrocarbons to blackcurrant sawfly from both males and females

Soft Fruit Agronomists' Day, 11 February 2016

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Gooseberry sawfly: GC-MS analyses

GC-MS analysis indicate possible trace of Z7-16:iPr ester

Gooseberry sawfly: GC-EAG analyses

Male gooseberry sawfly show strong EAG responses to components of blackcurrant sawfly pheromone

Minutes15.0 15.5 16.0 16.5 17.0 17.5 18.0 18.5 19.0 19.5 20.0

FID

- v

olts

0.00

0.05

0.10

0.15

0.20

0.25

EA

G m

illiv

olts

0

20

40

60

80

100

16

.07

17

.87

FIDMale Gooseberry 15070804.dat

Retention Time

EAGMale Gooseberry 15070804.dat

Retention Time

* * *

Z7-16:iPr

Z7-14:iPr

Z5-14:iPr

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GC-EAG analysis of pheromone collection from female gooseberry sawfly no EAG response at retention times of blackcurrant sawfly compounds

EAG response later

Gooseberry sawfly: GC-EAG analyses

Minutes15.0 15.5 16.0 16.5 17.0 17.5 18.0 18.5 19.0 19.5 20.0

FID

- v

olts

0.00

0.05

0.10

0.15

0.20

0.25

EA

G m

illiv

olts

0

20

40

60

80

1001

5.2

5

16

.44

16

.63

17

.48

17

.82

18

.24

18

.41

18

.76

FIDMale Gooseberry entrainment 15070803.dat

Retention Time

EAGMale Gooseberry entrainment 15070803.dat

Retention Time

*

Gooseberry sawfly: field trapping

Blends of components of blackcurrant sawfly pheromone tested in 8 growers’ fields during 2015 but no gooseberry sawfly caught

Soft Fruit Agronomists' Day, 11 February 2016

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Gooseberry sawfly: Conclusions

Presence of female sex pheromone demonstrated previously

Collections of volatiles from males and females show similar pattern of hydrocarbons

Male gooseberry sawfly give very strong EAG responses to iso-propyl ester components of blackcurrant sawfly pheromone

In GC-EAG analysis of volatiles from females, males show one EAG response at different retention time to components of blackcurrant sawfly pheromone

Traps baited with blends of components of blackcurrant sawfly not catch any gooseberry sawfly

Acknowledgements

HL01105/SF 012; SF147; SF165

Soft Fruit Agronomists' Day, 11 February 2016