Canadian Forest Service Publications
Interior spruce seedlings compared with emblings produced from somatic embryogenesis. I. Nursery development, fall acclimation, and over-winter storage. 1994. Grossnickle, S.C.; Major, J.E.; Folk, R.S. Canadian Journal of Forest Research 24: 1376-1384.
Issued by: Atlantic Forestry Centre
Catalog ID: 27453
Availability: PDF (download)
Interior spruce (Picea abies (Moench) Voss x Picea engelmannii Parry) seedlings and emblings (plants produced via somatic embryogenesis tissue culture) were grown as container 1+0 plants. Seedling and embling morphological development was monitored duirng the growing season. Needle freezing tolerance, days to terminal bud break (DBB), root growth capacity (RGC), and shoot dry weight fraction (DWF) were monitored during the fall and in frozen storage. Emblings had slower height, diameter, and root growth rates during the initial 2.5 months in the nursery. Thereafter, seedlings and emblings had equal height growth rate, while emblings had greater diameter and root growth rates. At the end of the growing season, seedlings and emblings, respectively, had 23.8 and 14.2 cm shoot height, 4.0 and 3.4 mm diameter, and 0.81 and 0.80 g root dry weight. During the fall, DBB of both seedlings and emblings decreased, with emblings having a more rapid decrease. Both seedlings and emblings showed a similar increase in freezing tolerance. Emblings had a greater increase in DWF. During the fall, RGC decreased then increased, with seedlings displaying a greater increase than emblings. While in frozen storage, seedlings and emblings maintained a low DBB, and a high RGC and DWF. Freezing tolerance decreased while in frozen storage, with the loss more pronounced among seedlings. A degree growth stage model describes the first year cycle of development for seedlings and emblings. Results indicate that seedlings and emblings were at the end of rest when lifted for frozen storage.