Pest management of cone and seed in Norway spruce ( L. Karst.) seed orchards in Sweden

Olle Rosenberg & Jan Weslien

Skogforsk Uppsala Science Park SE-75183 UPPSALA

Photo: Olle Rosenberg •Background

•Insects and their damage

•Pest management

•Pheromones Spruce seed orchards in Sweden

1:st set, 1955-1973, 200 ha 10% 2:nd set, 1983-1999, 200 ha 10-20 % 3:rd set, 2004- 200 ha 25-27 %

Hannertz, M. et al. 2000. Scots pine and Norway spruce seed orchards in Sweden -a description with an analysis of future seed supply. SkogForsk Redogörelse nr. 1. 40 pp. Rosvall, O. et al. 2001. Genetic gain from present and future seed orchards and clone mixes. SkogForsk Redogörelse nr 1. 41 pp. Rosvall, O. 2003. Zon- och ägarvisa plantagearealer för tredje omgången fröplantager i Sverige. Skogforsk Arbetsrapport 549, 42 pp. Number of spruce seeds/seedlings used in Sweden

Year 2001 2002 2003 2004 2005 2006 2007 2008 No. 172 172 186 188 194 198 232 236 x106 Swedish 36 % 41 % 45 % 50 % 50 % 47 % 48 % 47 % orchards

Source: Swedish Forest Agency Present 2010-14 2015-19 2020-24 2025-29 2030-34 2035-39 2040-44 2045-49 0 0

-10 -100

-20 -200

-30

-300

Base alternative -40 Intensive management -400 Flowerstimulation control -50 All 3

Kg spruce spruce Kg seeds per year -500

-60 Millions of of Millions spruce seedlings year per

-600 -70 Curt Almqvist, Skogforsk -700 -80 Photo: Olle Rosenberg

Photo: Olle Rosenberg Photo: Olle Rosenberg Photo: Olle Rosenberg

Photo: Mats Wilhelm Pettersson Photo: Olle Rosenberg Photo: Olle Rosenberg Photo: Olle Rosenberg Photo: Olle Rosenberg The gallmidges Kaltenbachiola strobi and Plemeliella abietina ♂ (Diptera: Cecidomyiidae)

Damages not visible from the cones exterior

Photo: Olle Rosenberg The spruce seed chalcid Megastigmus strobilobius (Hymenoptera: Torymidae)

Damage not visible from the cones exterior

Photo: Olle Rosenberg Pest management in spruce seed orchards Example of equipments for insecticide application

Photo: Olle Rosenberg Spraying of Btk using a tractor pulled air-blast sprayer on 6 m high trees in a spruce seed orchard in 2002

Photo: Olle Rosenberg •The conventional spraying was carried out at different phases of flowering

Photo: Kjell Lännerholm

Early flowering Late flowering Cone initiation Early cone development •Damage by D. abietella and/or E. abietaria was reduced from about 80 to 15 % in 1996, from 45 to 17 in 2000 and from 65 to 30 % in 2002

Weslien, J. 1999. Scand. J. For. Res. 14:127-130. Glynn, C. & Weslien, J 2004. J. Econ. Entomol. 97:1836-1841. Rosenberg, O & Weslien, J. 2005. J. Econ. Entomol. 98:402-408. Photo: Nils Jerling •Damage by D. abietella and/or E. abietaria was reduced from about 80 to 15 % in 1996, from 45 to 17 in 2000 and from 65 to 30 % in 2002

•No treatment effects on C. strobilella could be observed in any of the studies

Weslien, J. 1999. Scand. J. For. Res. 14:127-130. Glynn, C. & Weslien, J 2004. J. Econ. Photo: Olle Rosenberg Entomol. 97:1836-1841. Rosenberg, O & Weslien, J. 2005. J. Econ. Entomol. 98:402-408. Conventionally applied insecticides 2006

30

25

20 Control Water 15 Diflubenzuron 10 Acetamiprid

5 Percent of the cones

0 Damaged >10 %

Mean values of percent cones damaged by D. abietella and/or E. abietaria. In each treatment 30 trees were used as replicates. Conventionally applied insecticides 2007

2007

80 Control Acetamiprid 70 Azadirachtin 60 50 40 30 20

Percent of cones of the Percent 10 0 S. anthracina D. abietella C. strobilella

Mean values of percent cones damaged. In each treatment 10 trees were used as replicates. Conventionally applied insecticides 2008

100 90 80 70 60 Control 50 Btk 40 Fastac 30

Percentof the cones 20 10 0 S. anthracina D. abietella C. strobilella

Mean values of percent cones damaged. In each treatment 15 trees were used as replicates. Fastac (a.i. alphacypermethrin 50g/liter) is a broad spectrum insecticide that is effective against many species. Injection of two different insecticides in spruce trunks- efficacy of reducing damage by cone and seed insects

Photo: Olle Rosenberg

Photo: Nils Jerling In July 2005 and May 2006 we injected insecticides with the active substances abamectin (2% a.i.) and imidacloprid (5% a.i.) . One injection (1 ml) per 10-15 cm of the trees circumference. Injections in 2006

30 Control

25 Water

20 Abamectin

15 Imidacloprid

10

5 Percent of the cones

0 Damaged > 10 %

Mean values of percent cones damaged by D. abietella and/or E. abietaria. In each treatment 20 trees were used as replicates. Injections in 2005

30 C W 25 A 20 GA I 15 GI

10

Percent of the cones 5

0 Damaged >10%

Mean values of percent cones damaged by D. abietella and/or E. abietaria Seed quality

X-ray photo of seeds in order to find treatment related effect on quality and insects Pheromones

Photo: Olle Rosenberg Why pheromones ?

•Monitoring

•Attract and kill

•Mating disruption Catch of Dioryctria abietella

6

5

4

3

2 Catch perCatch trap day per

1

0

31 07 14 21 28 05 12 19 26 02 09 16 23 30

------

05 06 06 06 06 07 07 07 07 08 08 08 08 08

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2007 2007 2007 2007 2007 2007 2007 2007 2007 2007 2007 2007 2007 2007 Catch of Dioryctria abietella and accumulated degree days >5 C

2008 1600 16

1400 14

1200 12

1000 10

800 8

600 6

Ccatch Ccatch trapper per day Accum. degree days 5 > 400 4

200 2

0 0

16 30 14 28 11 02 16 30 13 27 23 07 21 04 18 25 09 23 06 20 03 10

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04 04 05 05 06 07 07 07 08 08 04 05 05 06 06 06 07 07 08 08 09 09

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2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 Catch of Dioryctria abietella and accumulated degree days >5 C

1600,0 0,8

1400,0 0,7

1200,0 0,6

1000,0 0,5

800,0 0,4

600,0 0,3

Catch perCatch trap day per Accum. degree days 5 >

400,0 0,2

200,0 0,1

0,0 0

06 13 11 18 15 22 29 27 03 31 07 05 12 19 20 27 04 25 01 08 06 13 20 10 17 24 14 21 28 26

------

04 04 05 05 06 06 06 07 08 08 09 10 10 10 04 04 05 05 06 06 07 07 07 08 08 08 09 09 09 10

------

2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 2009 Identification of the sex pheromone of the spruce seed , strobilella ()

•Cydia strobilella uses E,E-8,10-12:Ac and E,Z-8,10-12:Ac (ratio ≈3:2) as sex pheromone.

•The pheromone is produced in extremely low amounts (≈1 pg/female).

•Male antennae super-sensitive to the pheromone compounds.

Wang, H., Svensson, G.S., Rosenberg, O., Bengtsson, M., Jirle, E.V. & Löfstedt, C. 2010. Identification of the sex pheromone of the spruce seed moth, Cydia strobilella L. (:Tortricidae). J. Chem. Ecol. 36: 305-313 Summary

•Norway spruce do not flower each year, so when they do, it is important to protect the flowers from insect damages

•There are mainly 4 species that cause the severe damages

•Bacillus thuringiensis can decrease damages from Dioryctria and Eupithecia

•Fastac was more effective than Bacillus thuringiensis

•A combination of injectable insecticide and the flower stimulating hormone gibberellin may be possible and will increase the cost efficiency

•Pheromones will be a valuable help for better knowledge about the insects and for timing of insecticide application, may decrease the area that need to be sprayed and may also be directly used to control insects by mating disruption Financial support The Swedish Tree Breeding Association and The Swedish seed orchard owners

Photo: Mats Wilhelm Pettersson