Evidence for genetic control of response to sulfur dioxide and ozone in Populustremuloides

This study was designed to estimate the degree of genetic control of the response to sulfur dioxide (SO2) and ozone (O3), alone and in combination, in trembling aspen (Populustremuloides Michx.). Rooted cuttings from 11 randomly selected trees in central Wisconsin were used in the study. Significant interclonal variation was found in the response of the 11 clones to 3-h exposures to 0.50 ppm SO2, 0.20 ppm O3, and 0.35 ppm SO, plus 0.05 ppm O3. Clonal repeatability estimates of 0.464 for SO2 plus O3, 0.620 for O3, and 0.642 for SO2 suggest that much of this variation between clones can be attributed to genetic differences in response to SO2 and O3.

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Clonal variation in the incidence of Hypoxylon canker on trembling aspen

Canadian Journal of Botany ◽

10.1139/b74-194 ◽

1974 ◽

Vol 52 (7) ◽

pp. 1475-1481 ◽

Cited By ~ 9

Author(s):

James A. Copony ◽

Burton V. Barnes

Keyword(s):

Genetic Control ◽

Stand Density ◽

Genetic Differences ◽

Basic Unit ◽

Clonal Variation ◽

Biotic Factors ◽

Clonal Structure ◽

Trembling Aspen ◽

Phenotypic Differences ◽

Significant Difference

The incidence of Hypoxylon canker, caused by Hypoxylon mammatum (Whal.) Miller, on ramets of 80 pole-sized Populus iremuloides clones was determined on three sites near Pellston, Michigan, and two sites near Iron River, Michigan. Variation in the incidence of canker within clones was slight. No significant difference (P >.05) in canker incidence was found among NE, SE, SW, and NW quadrants of 47 clones on the Pellston Plain site. Significant differences (P <.005) were found among clones in the incidence of canker in four of the five sites studied. In some cases, nearby or adjacent pairs of clones showed significant and striking differences in the incidence of canker infection. The range in canker incidence (percentage of living and dead ramets with stem or branch cankers) for all clones was 9 to 90%; the range was wide on all sites. Low stand density and light bark color of ramets were both significantly (P <.01 and P <.05, respectively) correlated with high canker infection.Although genetic differences between clones in the incidence of canker were not proven, the marked phenotypic differences among clones and other findings suggested moderate genetic control on four of the five sites investigated. In studies relating the incidence of canker to site and biotic factors, the clonal structure of aspen stands should be recognized, and the clone should be used as the basic unit of sampling.

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Restoration of meiotic stability following artificial hybridisation and selection in Teleogryllus (Orth., Gryllidae)

Bulletin of Entomological Research ◽

10.1017/s0007485300005459 ◽

1973 ◽

Vol 62 (4) ◽

pp. 557-563 ◽

Cited By ~ 9

Author(s):

T. W. Hogan ◽

P. G. Fontana

Keyword(s):

Sex Ratio ◽

Genetic Control ◽

Sibling Species ◽

Parental Species ◽

Genetic Differences ◽

Hybrid Strain ◽

Cytological Examination ◽

Research Project ◽

Meiotic Stability ◽

Made In

As part of a research project directed at the genetic control of Teleogryllus commodus (Wlk.) in Australia, hybridisation studies have been carried out between T. commodus and the sibling species T. oceanicus (Le Guillou). A cytological examination of a hybrid strain (male progeny of T. commodus × T. oceanicus backcrossed to T. oceanicus) was made in the F4 generation when meiotic stability had been reached. The karyotype was very similar to that of T. oceanicus, suggesting that only those combinations in which the chromosomes were structurally homologous to T. oceanicus survived. But the stridulation pattern of the hybrid males, intermediate between that of the two parental species, and a consistent sex ratio of 2:1 in favour of the males, indicate profound genetic differences from T. oceanicus. These effects are attributed to introgression, with chromosomal material from T. commodus being incorporated in the T. oceanicus genome as an outcome of the initial hybridisation of the two species.

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Genetic control of DNA specificity inPseudomonas aeruginosa

Genetics Research ◽

10.1017/s0016672300011678 ◽

1968 ◽

Vol 12 (1) ◽

pp. 99-102 ◽

Cited By ~ 6

Author(s):

B. Rolfe ◽

B. W. Holloway

Keyword(s):

Genetic Control ◽

Genetic Differences ◽

Pleiotropic Effects ◽

Direct Selection ◽

Resistance Mutations ◽

Phenotypic Changes ◽

Dna Specificity

Genotypic and phenotypic changes of HCM inP. aeruginosaare due to a variety of causes. In addition to interstrain genetic differences and the semi-permanent effects of growth at 43°C, mutations affecting both restriction and modification have been isolated by direct selection and through the pleiotropic effects ofp–fluorophenylalanine resistance mutations. It is suggested that some of these changes affecting HCM may be taking place through alterations of the ribosomes.

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Relation of Crown and Foliage Traits to Height Growth of Sitka Spruce

Western Journal of Applied Forestry ◽

10.1093/wjaf/11.3.77 ◽

1996 ◽

Vol 11 (3) ◽

pp. 77-80

Author(s):

D. L. Copes ◽

W. H. Pawuk ◽

W. A. Farr ◽

R. R. Silen

Keyword(s):

Genetic Control ◽

Sitka Spruce ◽

Height Growth ◽

Picea Sitchensis ◽

Average Height ◽

Rooted Cuttings ◽

Field Plots

Abstract Four crown and foliage traits of a young Sitka spruce (Picea sitchensis) stand were tested with rooted cuttings in greenhouse and field plots for possible thinning selection guidelines. Repeatability estimates of the amount of genetic control over the four traits and the relation of those traits to height growth were evaluated 5 years after rooting. Only the blue-green trait was significantly associated (P < 0.05) with height growth. Average height of cuttings selected for green foliage was 17% greater than cuttings selected for blue foliage. Under greenhouse conditions, repeatability estimates of green or blue foliage were 98% versus 66%, respectively; 72% versus 89% for trees with dense or open crowns, respectively; 65% for the comparison of upright and horizontal branches; and 75% for the comparison of long or short branches. West. J. Appl. For. 11(3):77-80.

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

Canadian Journal of Forest Research ◽

10.1139/x00-017 ◽

2000 ◽

Vol 30 (5) ◽

pp. 837-840 ◽

Cited By ~ 7

Author(s):

T S Anekonda ◽

W T Adams ◽

S N Aitken ◽

D B Neale ◽

K D Jermstad ◽

...

Keyword(s):

Genetic Control ◽

Pseudotsuga Menziesii ◽

Cold Hardiness ◽

Genetic Correlations ◽

Douglas Fir ◽

Cold Injury ◽

Narrow Sense ◽

Family Selection ◽

Rooted Cuttings ◽

Breeding Populations

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.

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