Tree Improvement Program Project Report 2006 / 2007

.10 Inter or Spruce Tree
Breed ng Program
Barry Jaqu sh, Val Ashley, G sele Ph ll ps and
Bonn e Hooge
The Interior spruce tree-breeding program in British
Columbia is structured in two phases. Phase I began in
the mid-1960s and focussed on three geographic regions:
Prince George, Bulkley Valley, and the East Kootenay.
Phase II began in the mid-1970s and focussed on other
geographic regions where Interior spruce is commercially
and ecologically important. The program has progressed to
the point where much of the current planting stock (more
than 80 million seedlings per year) comes from rogued firstgeneration
seed orchards, and full-sib second-generation
progeny tests are in place for three seed planning units. In
2006, 65 trees in the 10-year-old Series I Prince George
Selection Unit second-generation progeny tests (Figure
13) were selected, grafted, and established in holding beds
where they will be held for one to two years and then
moved into seed orchards.
In the mid-1990s Interior seed planning zone review,
the Prince George Interior spruce SPU was realigned to
include six small seed planning units from the Phase II
program and the Prince George Selection Unit from the
Phase I program. This realignment resulted in a composite
breeding population of 1,140 tested parent trees for the
T R E E I M P R O V E M E N T P R O G R A M
P R O J E C T R E P O R T 2 0 0 6 / 2 0 0 7
new Prince George SPU. The second-generation crossing
plan for this new zone consisted of crossing the top 144
parents in a six-tree incomplete partial diallel crossing plan
where each parent was crossed with four other parents. This
plan resulted in 24 partial diallel units and a maximum of
288 crosses. Crossing was completed over four breeding
seasons, and four progeny tests were planted in spring
2006. These tests were established in an incomplete block
Alpha design with ten replications per site, 13 blocks per
replication, and 20 seedlots per block. Experimental units
consisted of three-tree row plots with trees planted at 2 x 2
m spacing (Figure 14).
In spring 2006, four realized gain tests were established
in the Prince George SPU. These tests will compare the
growth performance on an area basis of elite families, seed
orchard seedlots, and a wild-stand seedlot comprised of a
composite of ten wild-stand seedlots.
Site maintenance and measurements were conducted
on various research sites, including the 10-year-old East
Kootenay second-generation progeny tests, the spruce
seed orchard after-effects field tests near Prince George,
12 spruce climate change study sites, and the Chilliwack
Picetum.
Controlled crossing to produce full-sib families for
second-generation selection is ongoing in the Nelson
and Thompson Okanagan SPUs (breeding for TO SPU
conducted by Tolko Industries at the Eagle Rock seed
orchard).
F gure 13. Ten-year-old Ser es I
Inter or spruce second-generat on
progeny test near Pr nce George, BC.
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