Genetic variation in fall cold hardiness in coastal Douglas-fir in western Oregon and Washington

Genetic variation in fall cold damage in coastal Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco var. menziesii ) was measured by exposing excised branches of seedlings from 666 source locations grown in a common garden to freezing temperatures in a programmable freezer. Considerable variation was found among populations in fall cold hardiness of stems, needles, and buds compared with bud burst, bud set, and biomass growth after 2 years. Variation in fall cold hardiness was strongly correlated (r = 0.67) with cold-season temperatures of the source environment. Large population differences corresponding with environmental gradients are evidence that natural selection has been important in determining genetic variation in fall cold hardiness, much more so than in traits of bud burst (a surrogate for spring cold hardiness), bud set, and growth. Seed movement guidelines and breeding zones may be more restrictive when considering genetic variation in fall cold hardiness compared with growth, phenology, or spring cold hardiness. A regional stratification system based on ecoregions with latitudinal and elevational divisions, and roughly corresponding with breeding zones used in Oregon and Washington, appeared to be adequate for minimizing population differences within regions for growth and phenology, but perhaps not fall cold hardiness. Although cold hardiness varied among populations, within-population and within-region variation is sufficiently large that responses to natural or artificial selection may be readily achieved.

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Genetic selection for cold hardiness in coastal Douglas-fir seedlings and saplings

Canadian Journal of Forest Research ◽

10.1139/x00-114 ◽

2000 ◽

Vol 30 (11) ◽

pp. 1799-1807 ◽

Cited By ~ 16

Author(s):

Gregory A O'Neill ◽

Sally N Aitken ◽

W Thomas Adams

Keyword(s):

Genetic Control ◽

Cold Hardiness ◽

Genetic Correlations ◽

Genetic Selection ◽

Douglas Fir ◽

Direct Selection ◽

Bud Burst ◽

Individual Tree ◽

Breeding Populations ◽

Bud Set

Genetic control of cold hardiness in two-year-old seedlings was compared with that in 7-year-old saplings of 40 open-pollinated families in each of two breeding populations (Coast and Cascade) of coastal Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) from western Oregon. In addition, the efficacy of bud phenology traits as predictors of cold hardiness at the two stages was explored. Fall and spring cold hardiness were assessed using artificial freeze testing. Similar genetic control of cold hardiness in seedlings and saplings is suggested by strong type-B genetic correlations (rB) between the two ages for fall and spring cold injury traits (rB[Formula: see text] 0.78) and by similar trends in individual tree heritability estimates (hi2), e.g., hi2was greater in spring (hi2= 0.73) than in fall (hi2= 0.36) and greater in the Coast population (hi2= 0.69) than in the Cascade population (hi2= 0.40) at both ages. Strong responses to direct selection are expected for spring cold hardiness at both ages and for fall cold hardiness in seedlings, even under mild selection intensities. Similar heritabilities in seedlings and saplings, and strong genetic correlations between ages for cold-hardiness traits, ensure that selection at one age will produce similar gains at the other age. Type-A genetic correlations (rA) between fall and spring cold hardiness were near zero in the Cascade population (rA= 0.08 and -0.14 at ages 2 and 7, respectively) but were moderate and negative in the Coast population (rA= -0.54 and -0.36, respectively). Bud-burst timing appears to be a suitable surrogate to artificial freeze testing for assessing spring cold hardiness in both seedlings and saplings, as is bud set timing for assessing fall cold hardiness in seedlings, but bud set timing is a poor predictor of fall cold hardiness in saplings.

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Evidence of between-population differences in natural selection on extra-floral nectaries of the shrub Anemopaegma album (Bignoniaceae)

Botany ◽

10.1139/cjb-2015-0201 ◽

2016 ◽

Vol 94 (3) ◽

pp. 201-213

Author(s):

Anselmo Nogueira ◽

Pedro J. Rey ◽

Julio M. Alcántara ◽

Lúcia G. Lohmann

Keyword(s):

Genetic Variation ◽

Natural Selection ◽

Evolutionary Ecology ◽

Common Garden ◽

Phenotypic Selection ◽

Population Differences ◽

Wild Populations ◽

Neotropical Savanna ◽

Foliar Damage ◽

Floral Nectaries

Extra-floral nectaries (EFNs) are thought to represent protective adaptations against herbivory, but studies on the evolutionary ecology of EFNs have seldom been conducted. Here we investigate the patterns of natural selection and genetic variation in EFN traits in two wild populations of Anemopaegma album Mart. ex DC. (Bignoniaceae) that have been previously described as contrasting EFN – ant adapted localities in the Neotropical savanna (Cristália and Grão Mogol). In each population, four EFN descriptors, foliar damage, and reproductive success variables were measured per plant (100–120 plants per population). To estimate the heritability of EFN traits, we crossed reproductive plants in the field, and grew offspring plants in a common garden. The results showed that ant assemblages differed between populations, as did the range of foliar herbivory. Genetic variation and positive phenotypic selection in EFN abundance were only detected in the Cristália population, in which plants with more EFNs were more likely to reproduce. An evaluation of putative causal links conducted by path analysis corroborated the existence of phenotypic selection on EFNs, which was mediated by the herbivory process in the Cristália population. While EFNs could be currently under selection in Cristália, it is possible that past selection may have driven EFN traits to become locally adapted to the local ant assemblage in the Grão Mogol population.

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Growth, phenology, and cold hardiness of 32 Douglas-fir full-sib families

Canadian Journal of Forest Research ◽

10.1139/x09-092 ◽

2009 ◽

Vol 39 (10) ◽

pp. 1821-1834 ◽

Cited By ~ 11

Author(s):

B. J. Hawkins ◽

M. Stoehr

Keyword(s):

Cold Hardiness ◽

Shoot Growth ◽

Final Height ◽

Leaf Nitrogen ◽

Douglas Fir ◽

Bud Burst ◽

Freezing Damage ◽

Family Selection ◽

Growing Period ◽

Sib Families

Thirty-two full-sib families of coastal Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco var. menziesii) with a range of predicted breeding values were monitored for growth rate, phenology, and cold hardiness over 2 years on two sites to investigate if other traits are being selected when family selection is based on height. Significant differences among families existed in most phenological, growth, and cold-hardiness traits. On average, taller families burst bud later but did not have significantly different growth rates or length of growing period than other families. We found no significant correlations between family date of bud burst and cold hardiness in late spring or between duration of shoot growth or height and autumn freezing damage. Family differences in freezing tolerance were greatest in September and October. In these months, family current-year leaf nitrogen was positively correlated with cold hardiness. Families that were most hardy in the autumn were not the most hardy families in spring. We conclude that, for the studied breeding series, selection based on height does not have a significant impact on cold hardiness. We found no consistent relationships between phenological, growth, or cold-hardiness parameters and final height that could explain family ranking by height. Relationships between grandparent elevation and dates of bud burst and cold hardiness were observed.

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Correlated responses of height increment and components of increment in 2-year-old Douglas-fir

Canadian Journal of Forest Research ◽

10.1139/x89-170 ◽

1989 ◽

Vol 19 (9) ◽

pp. 1124-1130 ◽

Cited By ~ 12

Author(s):

Zeki Kaya ◽

R. K. Campbell ◽

W. T. Adams

Keyword(s):

Coastal Region ◽

Common Garden ◽

Douglas Fir ◽

Growth Patterns ◽

Early Selection ◽

Growing Seasons ◽

Bud Set ◽

Selection For ◽

The Difference ◽

Phenological Event

The consequences for growth and phenology of early selection for height or its growth components were evaluated in 160 open-pollinated families of Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) from southwestern Oregon. Seedlings from two inland and two coastal populations (40 families each) were grown for two growing seasons in a common garden. Predicted response to selection suggests that risk of low juvenile–mature correlation and maladaptation with early selection would be less in the inland than in the coastal region. A phenological event that influences a common growth pattern seems to account for the difference in response. Early bud set in the 1st year was genetically correlated with larger overwintering buds in seedlings from both inland and coastal regions. These larger buds yielded a large increment of predetermined growth in the 2nd year, followed by little or no free growth and early bud set. Seedlings with late bud set in the 1st year had the converse pattern. Inland seedlings set buds much earlier on the average than did coastal seedlings; hence seedlings from the two regions had different growth patterns. Risks that can attend early selection for height generally would be decreased in both regions by selecting for predetermined growth, but several qualifications are discussed.

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Genetic control of bud phenology in pole-size trees and seedlings of coastal Douglas-fir

Canadian Journal of Forest Research ◽

10.1139/x93-133 ◽

1993 ◽

Vol 23 (6) ◽

pp. 1043-1051 ◽

Cited By ~ 35

Author(s):

Peng Li ◽

W.T. Adams

Keyword(s):

Genetic Control ◽

Growth Traits ◽

Douglas Fir ◽

Bud Burst ◽

Age Classes ◽

Breeding Programs ◽

Bud Set ◽

Bud Phenology ◽

Selection For ◽

Lateral Branches

The extent to which bud phenology is genetically controlled and related to growth traits was examined in seedlings and pole-size trees of coastal Douglas-fir (Pseudotsugamenziesii var. menziesii (Mirb.) Franco). Data on bud burst, bud set, and stem growth were collected from pole-size trees of 60 open-pollinated families growing in four plantations, and from seedlings of 45 of these same families growing in three trials. In both age-classes, bud burst was under moderate to strong genetic control (h2 ≥ 0.44) and family breeding values were stable across test environments, indicating that this trait could be readily altered in breeding programs. Bud set was inherited strongly in pole-size trees (h2 = 0.81) but weakly in seedlings (h2 < 0.30). Both bud burst and bud set were positively correlated with growth in seedlings and pole-size trees. Thus, selection for greater growth at either age-class is expected to delay bud burst and bud set. We also evaluated the accuracy of two alternatives for assessing bud burst phenology in pole-size trees compared with the traditional method. We show that bud-burst date on lateral branches can be used to accurately rank both individuals and families for bud-burst date on less accessible leader shoots. In addition, we found that families can be ranked for mean bud-burst date by the proportion of trees per family that have flushed on a given scoring day. This method is only effective, however, when between 25 and 75% of all trees in the test have flushed at the time of scoring.

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Genetic Variation in Cold Hardiness and Phenology Between and Within Turkish Red Pine (Pinus brutia Ten.) Populations: Implications for Seed Transfer

Silvae Genetica ◽

10.1515/sg-2010-0006 ◽

2010 ◽

Vol 59 (1-6) ◽

pp. 49-57 ◽

Cited By ~ 7

Author(s):

G. E. Kandemir ◽

Zeki Kaya ◽

F. Temel ◽

S. Önde

Keyword(s):

Cold Hardiness ◽

Eastern Mediterranean ◽

Final Height ◽

Red Pine ◽

Bud Burst ◽

Pinus Brutia ◽

Bud Set ◽

Cold Damage ◽

Natural Range ◽

Turkish Red Pine

Abstract Wind-pollinated seeds from 40 trees (half-sib families) were collected from each of six Turkish red pine (Pinus brutia Ten.) populations in southern Turkey. Two-year old seedlings were evaluated for growth, phenology and cold resistance in a common garden experiment established in Ankara, located outside the species’ natural range. Each family was represented with a six-tree row plot within each of the three replications. The below freezing temperatures (-15.2°C) observed in January and February of 2000 were sufficient to observe visually- assessable-cold damage to the seedlings. The populations significantly differed in all traits under investigation except for second flushing in 1999. Populations originating from more inland and higher elevation areas were more resistant to cold than coastal low elevation populations. Families within populations were significantly different as regards all traits except HT00. Family heritability for bud burst was 0.40, and ranged from 0.12 to 0.37 for height, and from 0.20 to 0.23 for bud set. Final height of cold damage prone seedlings was shorter than cold tolerant seedlings. Families with early bud-set, later bud-burst and shorter second flush shoots suffered less from cold damage. Considering the expected climate change in the eastern Mediterranean, there is a potential for using this species outside its natural range, especially in sites experiencing more continental climate since it will be possible to move the species 200-300 m in altitude and 2-3 degrees in latitude.

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Ecological adaptations in Douglas-fir (Pseudotsugamenziesii var. glauca) populations. III. Central Idaho

Canadian Journal of Forest Research ◽

10.1139/x83-090 ◽

1983 ◽

Vol 13 (4) ◽

pp. 626-632 ◽

Cited By ~ 12

Author(s):

Gerald E. Rehfeldt

Keyword(s):

Cold Hardiness ◽

High Growth ◽

Frost Damage ◽

Douglas Fir ◽

Growth Potential ◽

Bud Burst ◽

Population Means ◽

Spring Frost ◽

Selection For ◽

Central Idaho

Growth, phenology, and cold hardiness of seedlings from 74 populations of Douglas-fir (Pseudotsugamenziesii var. glauca (Beissn.) Franco) from central Idaho were compared in four contrasting environments. Analyses of 3-year-old seedlings revealed population differentiation for eight variables: bud burst, bud set, multiple flushing, height, deviation from regression of 3-year height on 2-year height, spring frost damage, fall frost damage, and winter injury. These analyses, as well as high intercorrelations among population means, suggested that adaptations result from a balance between selection for a high growth potential in mild environments and selection for cold hardiness in severe environments. Consequently, genetic variation among populations was closely related to the elevation, geography, and climate of the seed source.

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The effect of nursery blackout application on Sitka spruce seedlings

Canadian Journal of Forest Research ◽

10.1139/x26-249 ◽

1996 ◽

Vol 26 (12) ◽

pp. 2201-2213 ◽

Cited By ~ 10

Author(s):

C.D.B. Hawkins ◽

A.M. Eastham ◽

T.L. Story ◽

R.Y.N. Eng ◽

D.A. Draper

Keyword(s):

Cold Hardiness ◽

Common Garden ◽

Sitka Spruce ◽

Day Length ◽

Root Weight ◽

Growing Seasons ◽

Control Stock ◽

Bud Set ◽

Terminal Bud ◽

Dynamic Treatment

Sitka spruce (Piceasitchensis (Bong.) Carrière) seedlings were cultured using two nursery methods of blackout (short photoperiod) application: static treatment (constant day length of 14.28 h) and dynamic treatment (day length varying over length of experiment, with a mean of 14.28 h). Both methods when compared with a control (natural day length) reduced seedling height by inducing terminal bud set, increased seedling root weight, and decreased shoot to root and sturdiness ratios. Both static and dynamic blackout treatment seedlings had 26 and 30% lammas flush, respectively. Compared with control, both methods accelerated cold hardiness acquisition. After winter storage at −2 °C, treated seedlings flushed sooner than did control stock under light:dark temperatures of 25:20 °C. Under a cooler regime, 15:5 °C, differences among treatments were not significant. After planting in a common garden trial, terminal bud phenology had a range of treatment responses. Control seedlings flushed later and set bud sooner. Dynamic treatment seedlings' bud set phenology was nearest to that of controls. At a common garden trial and a reforestation site, blackout-treated seedlings had greater first-season terminal height increment. Planting check was observed for all treatments in the field during the second and third growing seasons. After five field seasons there was no height difference among treatments, and survival averaged 87%. Groundline stem diameter was never different among treatments. Biologically, the dynamic treatment is intermediate between the static and control treatments, but the static treatment is recommended because it is easier to apply in the nursery, and differences between the dynamic and static treatments were minimal.

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