Pest Management in Swedish Spruce Seed Orchards

Transcription

1 Pest Management in Swedish Spruce Seed Orchards Olle Rosenberg Jan Weslien Skogforsk Uppsala Science Park SE UPPSALA

2 Spruce seed orchards in Sweden 1:st set, , 200 ha 10% 2:nd set, , 200 ha % 3:rd set, >200 ha % Only first and second set orchards are visible in the figure. Hannertz, M. et al Scots pine and Norway spruce seed orchards in Sweden -a description with an analysis of future seed supply. SkogForsk Redogörelse nr pp. Rosvall, O. et al Genetic gain from present and future seed orchards and clone mixes. SkogForsk Redogörelse nr pp. Rosvall, O Zon- och ägarvisa plantagearealer för tredje omgången fröplantager i Sverige. Skogforsk Arbetsrapport 549, 42 pp.

3 Number of spruce seedlings used in Sweden Year No. x Swedish orchards Foreign orchards Foreign stands 36 % 41 % 45 % 50 % 50 % 47 % 48 % 47 % 56 % 59 % 57 % 1 % 2 % 3 % 1 % 12 % 2 % 1 % 7 % 6 % 5 % 5 % 26 % 32 % 27 % 22 % 17 % 34 % 37 % 32 % 24 % 19 % 22 % Source: Swedish Forest Agency

4 , % of the cones infested by the cone maggot, Strobilomyia anthracina Photo: Olle Rosenberg Photo: Olle Rosenberg Photo: Mats Wilhelm Pettersson

5 , % of the cones infested by the seed moth, Cydia strobilella

6 , % of the cones infested by the coneworm Dioryctria abietella (the darker larva and imago) and the cone looper Eupithecia abietaria

7 Infestation rate, crop size and monitoring data from Ålbrunna Year Cones damaged (%) Cones/ha Trap catch D. abietella S. anthracina C. strobilella D. abietella Cones per ha infested by Da

8 Pest management in spruce seed orchards Example of equipments for insecticide application I

9 Large-scale application of Bacillus thuringiensis variety aizawai x kurstaki (Btk) against lepidopterans Use water sensitive papers in order to see if the spray droplets reach the flowers.

10 The conventional spraying was carried out at different phases of flowering Photo: Kjell Lännerholm Early flowering P1 Late flowering P2 Cone initiation P3 We found best results when spraying Btk during late flowering to cone initiation Early cone development P4

11 Damage by D. abietella and/or E. abietaria was reduced from 65 to 30 % Photo: Nils Jerling

12 Damage by D. abietella and/or E. abietaria was reduced from 65 to 30 % No treatment effect on C. strobilella could be observed

13 No. Seeds per cone Effects of different insect species on Norway spruce seeds Total Filled No insects Cs Sa Cs+Sa Da Da+Cs Da+Sa Da+Sa+Cs Mean number of seeds (total and filled) per cone ±SE. Cs = Cydia strobilella, Sa = Strobilomyia anthracina and Da = Dioryctria abietella The result imply that seed number increase as number of species decrease

14 Percent of the cones Conventionally applied insecticides Control Water Diflubenzuron Acetamiprid 5 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.

15 Percent of the cones Conventionally applied insecticides Control Btk Fastac S. anthracina D. abietella C. strobilella Mean values of percent cones damaged. In each treatment 15 trees were used as replicates. Fastac (a.i. alpha-cypermethrin 50g/liter) is a broad spectrum insecticide that is effective against many species.

16 Stem injections with insecticide and gibberellin reduce cone damage and increase flowering in a spruce seed orchard Photo: Nils Jerling Insecticides were injected in July 2005 and May One injection (1 ml) per cm of the trees circumference.

17 Percent of the cones Injections in Control 25 Water 20 Abamectin 15 Imidacloprid Damaged > 10 % Mean values of percent cones damaged by D. abietella and/or E. abietaria. In each treatment 20 trees were used as replicates.

18 Injections in 2005 Mean proportion ±SE of cones infested by D. abietella / E. abietaria. c = control, w = water, a = abamectin, ginj = gibberellin injection, gdrill = gibberellin drill method, i = imidacloprid

19 Infested cones (%) Injection Control Abamectin Emamectin benzoate Total Damage >10 % Mean proportion of cones infested by D. abietella. Injections were applied in early July 2012 according to the label for abamectin (One injection (1 ml) per cm of the trees circumference).

20 Some aspects of different insecticide systems Conventional application of pesticides is faster compared to injections Injections of insecticide and gibberellin can be made at the same time Injection have less effect on the surrounding environment

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

22 Pheromones

23 Why pheromones? Monitoring Attract and kill Mating disruption

24 Accum. degree days > 5 Catch per trap per day 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 0,3 400,0 0,2 200,0 0,1 0,0 0

25 Summary Norway spruce do not produce cones every year, so when they do, it is important to protect the cones from insect damage There are mainly four species that cause severe damage in Sweden Bacillus thuringiensis can decrease damage from Dioryctria and Eupithecia Alpha-cypermethrin was more effective than Bacillus thuringiensis A combination of injectable insecticide and the flower stimulating hormone gibberellin may be possible and thereby increase the cost efficiency Pheromones can 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

26 A possible decision scheme The year before expected flowering - Injection of gibberellin and insecticide Flowering year - Spraying of Btk - Injection of insecticide in particularly valuable trees - Monitoring of pest insects using pheromone baited traps - Spraying of some insecticide effective by contact if there is a need - Direct control of insects using pheromone (disruption, attract and kill)

27 Cone rust, Thekopsora areolata Test with fungicide Sanitation picking of all cones Inoculation

28 Financial support The Swedish Tree Breeding Association and The Swedish seed orchard owners Co-workers Gibberellin: Curt Almqvist Pheromones: Christer Löfstedt Photo: Mats Wilhelm Pettersson