Sitka Spruce Tree Breeding Program
Sitka spruce (Picea sitchensis (Bong.) Carr.) is an integral component of the coastal rainforest of western North America. A pest resistance screening and breeding program against the white pine weevil (Pissodes strobi) has been ongoing in British Columbia since the early 1980s.
In recent years, the main effort has been monitoring weevil attacks in the first-generation (F-1) trials. The last site where F-1 trials were established, located at Pinch Creek, was augmented with weevils in 2015. The evaluation that followed found that fewer than three percent of trees became infested with weevils.
In addition to ongoing monitoring for weevil attacks, the Sitka spruce program plans to provide an analysis of all genetic trials to date, in order to provide both resistance and growth estimates for orchard upgrading. Depending on the results, stable and effective resistance with volume gain may be delivered through current upgraded orchards. The selections from these trials may undergo another cycle of weevil enhancement for further development of resistance and volume gain.
- Alfaro, R.I., King, J.N. and vanAkker, L. 2013. Delivering Sitka spruce with resistance against white pine weevil in British Columbia, Canada. Forestry Chronicle 89(2): 235-245.
- King, J.N. R.I. Alfaro, P. Ott and L. vanAkker. 2012. Phenotypic evidence suggests a possible major-gene element to weevil resistance in Sitka spruce. In: Sniezko, Richard A.; Yanchuk, Alvin D.; Kliejunas, John T.; Palmieri, Katharine M.; Alexander, Janice M.; Frankel, Susan J., tech. coords. 2012. Proceedings of the fourth international workshop on the genetics of host-parasite interactions in forestry: Disease and insect resistance in forest trees. Gen. Tech. Rep. PSW-GTR-240. Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture. pp. 54-64.
- King, J.N. R.I. Alfaro, M. Grau Lopez and L. vanAkker. 2011. Resistance of Sitka spruce (Picea sitchensis (Bong.) Carr.) to white pine weevil (Pissodes strobi Peck): characterizing the bark defence mechanisms of resistant populations. Forestry 84(1):83-91.
- Robert, J.A. , Madilao, L.L., White, J., Yanchuk A., King, J.N., and Bohlmann J. 2010. Terpenoid metabolite profiling in Sitka spruce identifies association of dehydroabietic acid, (+)-3-carene, and terpinolene with resistance against white pine weevil. Botany 88(9): 810-820.
- Developing Sitka spruce populations for resistance to the white pine weevil: summary of research and breeding program. B.C. Min. For. Range, Res. Br., Victoria, B.C. Tech. Rep. 050.