Skógræktarritið - 15.05.2001, Blaðsíða 191

Table 1. Species, provenances and families in the freezing test. SS=Sitka spruce,
LS=Lutz spruce, WS=White spruce ES=Engelmann spruce, BS=Black spruce.
Nr.Provenance Species Species /cpDNA Lat. (°N) Long. (°V) Alt. (m) Fainilu"
1 Chiniak SS ss 57°36’ - 37' 152°10' - 18' 10-30
2 Duck Mountain ss ss 58° 12' 152°3 ' 50-80
3 Iniskin Bay SS/LS SS/LS 59°41' I53°23' 8-100
4 Chinitna IJay ss SS/LS 59°49’ 153°02' - 05' 5-20
5 Port Chatham ss ss 59°ir 151°43' 30
6 Homer ss SS 59°38' 151°28' - 34' 5-30 10
7 Ninilchik LS/WS LS/WS 59°58' - 59' 151°33' - 35' 91-122 10
8 Kenai Citv WS ws 60°35' - 40' 151°17'-20' 20-30
9 Resurrection River ss ss 60°09’ - 11’ 149=27'-32' 15-61 i
10 NashRoad ss ss 60°05’-08’ 149°20’-24' 3-61
11 Kenai Lake LS ws 60°29' 149°45'-47' 152 4
12 Cooper Lake ss LS/SS 60°21’ 149°41' - 44' 396 5
13 Moose Pass ss LS/SS 60°15'-24' 149=21'-22' 145-213 2
15 Hope Road LS 4
17 Portage to Girdwood ss SS 60°47' -51’ 149°44’ - 55’ 23-76 5
18 Girdwood ss ss 61 149°30' 6
19 Valdez ss SS 61°04' 146°11' 31 10
20 Cordova ss SS 60°32’ 145°45' 10
21 Icy Bay ss SS 60°03’ 142° 13' 8 3
26 Haines Highway ss 59°40' 130°30' 758
28 Dyea, Skagway ss 59°27' 135° 19' 6
29 Yakutat ss 59°31’ 139°40' 8,5
30 Cordova ss 60°32' I45°45' 8
31 Tatiklek ss 61 °00' 146°40'
32 Taraldsdv ss Seedorchard, trees of various origin
33 Sitka ss 57°00' 135°30' a
34 Ártúnsbrekka ss Icelandic provenance, trees of various origin
35 Tumastaðir ss Icelandic provenance, trees of various origin a.
36 Stálpastaðir ss Icelandic provenance, origin Cordova
46 Quecn Charlotte ss 53°21' 132°15' 167 >>
47 Porcher Island ss 54°03' 130°20' 427 c c
48 Rennell Sound ss 53°20' 132° 18' 475
57 Rio Grande, Colorado ES 38° 105°
58 Bluejoint Mtn. ES 51° 116° \
60 Soldotna BS 60°30' 151 °00' 25
was freeze tested in the spring
and fall of 1996 (Table 1).
Shoots were cut from 2-year'
old potted seedlings and sub-
jected to freezing at two times
during spring and two times dur-
ing fall in 1996. On each date,
two minimum temperatures were
used, -12 and -18°C, with the
temperature decreasing by 2° per
hour to these levels. The shoots
were then placed on a rooting
bench in a warm and humid
greenhouse for 14 days. The
shoots were then dissected lon-
gitudinally and damage to tis-
sues and buds assessed (Figs. 1
and 2).
Results
Provenances of white spruce and
Lutz spruce were more sensitive
to spring frost damage than Sitka
spruce provenances but the
reverse was true for fall frost
damage. The provenance differ-
ences were significant, being
more pronounced in fall. The
proportion of introgressed white
spruce genes seems to be the
most important determining fac-
tor (Figs. 3 and 4).
Significant differences were
found in frost hardiness between
half-sib. families within most
provenances with the greatest
differences being within Lutz
spruce provenances. The results
indicate that it is possible to
select families that show good
frost tolerance both spring and
fall.
Early selection and improve-
ment for frost tolerance
Based on these results, it can be
concluded that emphasis should
be on selection of 1) species and
2) families that show the desired
forst tolerance characteristics.
Families should be selected from
within provenances that show
Figure 3. Frost damage in shoot tis-
sue. Freezing 18. April at-18°C. Mark
50 indicates brown or black decom-
posed tissue in the whole shoot (5 cm
x 10). The error bars indicates stan-
dard deviation. Legend: Sitka spruce
•, white spruce O, Ititz spruce I, black
spruce s and engelmannspruce
SKÓGRÆKTARRITIÐ 2001 l.tbl.
189