Managing a model population to market the potential of breeding

1. Managing a model population to market the potential of breeding Bengt Andersson, SkogForsk, Box 3, SE-918 21 Sävar, Sweden • Tree breeding characteristics • Model population • Goals • Techniques • Breeding strategies • Standard • Model • Combined • Advantages/disadvantages

2. Breeding of forest trees • Long generation intervals • Low genetic gain per time • Postponed return from breeding investments

3. Breeding populations for - increased yield - climatic change prep. - gene conservation Photoperiod (latitude) Temperature climate (growing season days)

4. Model population Primary goals • Shorten generation time to 1/3 • Unchanged gain • Unchanged diversity Operational size • 19 selected parent trees (50 normally) • 20 full-sib families (50 normally) • 760 candidate trees (500 normally)

5. Model population - components • Exclude time lag for sexual maturity • Vegetative propagation • Clonal testing • Early tests for evaluation/selection • NIR (Near InfraRed reflection) for hardiness • MI (Mitotic Index) for growth • Field performance for 2nd stage selection • Early flowering for generation turnover • Top-grafting with young scions • Accelerated growth of selected individuals

14. Model population - components • Exclude time lag for sexual maturity • Vegetative propagation • Clonal testing • Early tests for evaluation/selection • NIR (Near Infrared Reflection) for hardiness • MI (Mitotic Index) for growth • Field performance for 2nd stage selection • Early flowering for generation turnover • Top-grafting with young scions • Accelerated growth of selected individuals

16. superior average Fig. Breeding values (BLUPs) of 13 Scots pine clones, based on progeny performance in field trials. (Andersson)

17. MI Julian day Fig. Mitotic index (MI) from pooled superior () and average ()clones between April 25 and Oct. 24. (Sundblad et al.)

18. Observed damage (EC) Predicted damage (NIR) Fig. Predicted damage (Near Infra Red reflection - NIR) and observed damage after freezing (Electrolytic Conductivity - EC), of Scots pine seedlings from latitude 53-67. (Sundblad et al.)

19. Top-grafting for early flowering

20. 500 F1 candidates evaluation F2 20.000 F2 progeny trials pc 50 P, dpm 50 P, dpm selection 50 F1, dpm selection 50 F1, dpm 0 0 2 2 12 12 15 15 25 25 Year Year veg. prop. 500 x 10 top-grafting early test evaluation 4 8 Standard strategy Model strategy

21. Combined strategy - an example early test evaluation, (top-grafting), transplanting to field early test evaluation, field test evaluation 50 P, dpm veg. prop. 2000 x 10 (top-grafting) veg. prop. 2000 x 10 50 x 40 F1 candidates 200 x 10 F2 candidates final, combined index selection 100 x 2 F2 primary selection 50 x 4 F1, dpm Year 0 2 4 8 10 12 16

22. Model population - concluding remarks • Strong points • Substantial time reduction possible • Techniques seem promising • Each activity independent of others • Weak points • Techniques still need development • Selections based on early tests • Culling (vegetative prop., early flowering)