Genetics of cold hardiness in a cloned full-sib family of coastal Douglas-fir

2000 ◽  
Vol 30 (5) ◽  
pp. 837-840 ◽  
Author(s):  
T S Anekonda ◽  
W T Adams ◽  
S N Aitken ◽  
D B Neale ◽  
K D Jermstad ◽  
...  

Variation in cold-hardiness traits, and their extent of genetic control and interrelationships, were investigated among individuals (clones) within a single large full-sib family of coastal Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) from Oregon. Cold injury to needle, stem, and bud tissues was evaluated in fall 1996 and spring 1997 following artificial freeze testing of detached shoots collected from 4-year-old ramets (rooted cuttings). Variation among clones in cold-injury scores was significant (p < 0.01) for all shoot tissues in both fall and spring and averaged about three times the magnitude previously observed among open-pollinated families of this species. Thus, improving cold hardiness by within-family selection appears to hold much promise. Striking similarities in relative magnitudes of heritability estimates and genetic correlations in the full-sib family, compared with breeding populations, support the following hypotheses about the quantitative genetics of cold hardiness in this species: (i) heritability of cold hardiness (both broad-and-narrow-sense) is stronger in the spring than in the fall; (ii) cold hardiness of different shoot tissues in the same season is controlled by many of the same genes; and (iii) genetic control of fall cold hardiness is largely independent of cold hardiness in the spring.

2000 ◽  
Vol 30 (11) ◽  
pp. 1799-1807 ◽  
Author(s):  
Gregory A O'Neill ◽  
Sally N Aitken ◽  
W Thomas Adams

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 (h–i2= 0.73) than in fall (h–i2= 0.36) and greater in the Coast population (h–i2= 0.69) than in the Cascade population (h–i2= 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.


1996 ◽  
Vol 26 (10) ◽  
pp. 1828-1837 ◽  
Author(s):  
S.N. Aitken ◽  
W.T. Adams

Genetic variation in fall cold hardiness was studied in two western Oregon breeding populations of coastal Douglas-fir (Pseudotsugamenziesii var. menziesii (Mirb.) Franco), one on the west slope of the Cascade Mountains and the other in the Coast Range. On six sampling dates (September, October, and November of 1992 and January, September, and October of 1993), shoot cuttings from 40 open-pollinated families in each of two progeny test sites for each breeding zone were subjected to artificial freezing at two test temperatures. Damage on each shoot was recorded as visible injury to needle, stem, and bud tissues separately. Considerable family variation was found for cold injury scores in all tissues in early fall to midfall, but differences were often smaller or nonsignificant in late fall and midwinter. Individual heritability estimates for needle cold injury were low (<0.40) and generally decreased in late fall and midwinter. Family rankings for fall cold hardiness, however, are expected to be relatively consistent over sites and years, although needles appear to display more family-by-site interaction than stems or buds. Genetic correlations between tissues in cold injury varied considerably and were sometimes weak, indicating that the evaluation of a single tissue is probably not adequate for assessing overall cold hardiness of genotypes. Fall and winter cold hardiness seem to be largely under separate genetic control since genetic correlations between hardiness at these two stages were weak. This study confirms earlier results in Washington breeding populations and shows that coastal Douglas-fir families can be effectively ranked for fall cold hardiness by conducting artificial freeze tests on cut shoots in midfall (October) and scoring damage to stems and at least one other tissue.


2008 ◽  
Vol 38 (6) ◽  
pp. 1536-1546 ◽  
Author(s):  
Nicholas K. Ukrainetz ◽  
Kyu-Young Kang ◽  
Sally N. Aitken ◽  
Michael Stoehr ◽  
Shawn D. Mansfield

Genetic control and relationships among coastal Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco var. menziesii) growth and wood quality traits were assessed by estimating heritability and phenotypic and genetic correlations using 600 trees representing 15 full-sib families sampled from four progeny test sites. Heritability estimates ranged from 0.23 to 0.30 for growth traits, 0.19 for fibre coarseness, from 0.21 to 0.54 for wood density, from 0.16 to 0.97 for cell wall carbohydrates, and 0.79 and 0.91 for lignin content at two sites, Squamish River and Gold River, respectively. Glucose content, indicative of cell wall cellulose composition, and lignin were shown to be under strong genetic control, whereas fibre coarseness was shown to be under weak genetic control. Phenotypic correlations revealed that larger trees generally have longer fibres with higher fibre coarseness, lower density, lower carbohydrate content, a greater proportion of cell wall lignin, and higher microfibril angle. Genetic correlations and correlated response to selection suggest that breeding for height growth would result in a reduction in wood quality, whereas breeding for improved earlywood density in Douglas-fir would result in negligible reductions in volume and appears to be an ideal target for selecting for improved wood quality (density) while maintaining growth in the sample population.


2009 ◽  
Vol 39 (10) ◽  
pp. 1821-1834 ◽  
Author(s):  
B. J. Hawkins ◽  
M. Stoehr

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.


2005 ◽  
Vol 35 (3) ◽  
pp. 521-529 ◽  
Author(s):  
Fatih Temel ◽  
G R Johnson ◽  
W T Adams

The possibility of early testing coastal Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) for Swiss needle cast (SNC; caused by Phaeocryptopus gaeumannii (Rohde) Petrak) tolerance was investigated using 55 Douglas-fir families from western Oregon. Seedlings were inoculated with P. gaeumannii naturally in the field and were visually scored for a variety of SNC symptom traits (i.e., needle and foliage color, and retention) at the seedling stage (age 2) and in "mature" (ages 10 and 12) trees at two test sites for both the seedling and mature ages. Seedlings were also assessed in the laboratory for SNC symptom traits, for proportion of needle stomata occluded with pseudothecia (PSOP), and for amount of P. gaeumannii DNA in needles. Although families differed significantly at both ages for all SNC symptom traits and for PSOP, they did not differ for amount of fungal DNA. Thus, genetic variation in SNC symptoms appears to be primarily due to differences in tolerance to the disease rather than to resistance to infection per se. Estimated individual-tree heritabilities for SNC symptom traits were low to moderate (mean hi2 = 0.19, range 0.06–0.37) at both ages, and within each age-class these traits were moderately to strongly genetically correlated (mean rA = 0.69, range 0.42–0.95). Type B genetic correlations between SNC symptom traits in seedlings and mature trees ranged from 0 to 0.83 and were weakest for traits measured in the laboratory. Genetic gain estimates indicated that family selection for SNC tolerance (i.e., greener needles or greater foliage retention) at the seedling stage can be very effective in increasing tolerance in older trees.


2015 ◽  
Vol 21 (10) ◽  
pp. 3814-3826 ◽  
Author(s):  
Sheel Bansal ◽  
J. Bradley St. Clair ◽  
Constance A. Harrington ◽  
Peter J. Gould

1979 ◽  
Vol 25 (4) ◽  
pp. 576-582
Author(s):  
John Blake ◽  
Joe Zaerr ◽  
Stephen Hee

Abstract Nursery-grown seedlings of Douglas-fir (Pseudotsuga menziesii) were subjected to three levels of moisture stress between late July and the end of August. Measurements in October and December showed that mild stress of -5 to -10 bars significantly improved cold hardiness. In a second experiment, the effectiveness of the mild stress treatment decreased as the onset of the stress was delayed from mid-July until September 1. Furthermore, the earlier onset of stress decreased the height and shoot/root ratio, but increased the root weight and nitrogen content of the needles. For seedlings lifted in October, mild stress also decreased mortality from cold storage. Forest Sci. 25:576-582.


2012 ◽  
Vol 61 (1-6) ◽  
pp. 186-198 ◽  
Author(s):  
T. Z. Ye ◽  
K. J. S. Jayawickrama

AbstractMeasurements on growth traits up to 41 years of age from 68 progeny sites in eight first-generation breeding zones of coastal Douglas-fir (Pseudotsuga menziesii [MIRB.] FRANCO var. menziesii) in the US Pacific Northwest were used to investigate age trends of genetic parameters and to determine optimum age of selection. Heritabilities and age-age genetic correlations were estimated using univariate or bivariate mixed model analyses. Heritability estimates tended to increase with age for both total growth and growth increment traits. The estimates showed different age trends among breeding zones, but the differences were generally small. Age-age genetic correlations for total growth traits fitted Lambeth’s model surprisingly well, despite the data being collected from multiple breeding zones. Using rotation-age (i.e., 50yr) volume as the selection criterion, the greatest correlated gains per year were achieved by making family selection at juvenile ages (i.e., 9 for height, 13 for diameter, and 11 for volume). Similar results were obtained for within-family selection except that the optimum ages of selection were 2~4 years later than that from family selection, i.e., 11 for height, 15 for diameter and volume. Early selection on total height was always more efficient and had earlier optimum ages than on other growth traits. The optimum ages of early family selection on total growth were 4~11 years earlier than on the corresponding growth increment traits. It was also evident that the optimum ages of selection occurred later for slow-growth trials than for fast-growing trials.


2008 ◽  
Vol 65 (1) ◽  
pp. 102-102 ◽  
Author(s):  
Alejandro G. Martinez Meier ◽  
Leopoldo Sanchez ◽  
Guillermina Salda ◽  
Mario J. M. Pastorino ◽  
Jean-Yves Gautry ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document