Skog er viktig i Norge. Det er uttalt politisk vilje til å styrke skogens bidrag for økonomisk verdiskaping i landbruket og for å nå viktige mål knyttet til energi, klima, miljøverdier og økosystemtjenester. Skogressursene er viktige for... more
Skog er viktig i Norge. Det er uttalt politisk vilje til å styrke skogens bidrag for økonomisk verdiskaping i landbruket og for å nå viktige mål knyttet til energi, klima, miljøverdier og økosystemtjenester. Skogressursene er viktige for å opprettholde et bærekraftig landbruk og matproduksjon over hele landet, ettersom inntekt fra skogen bidrar til den totale inntekten for mange aktive bønder. Skogene er også viktige for rekreasjon og for folkehelsa. Skogtregenetiske ressurser i Norge brukes i produksjonsskogbruk, til skogplanting etter hogst og på annet areal, eller til treslagsskifte. De brukes også til juletreproduksjon, til landskapsformål eller i parker og hager...
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Complete diallel crosses were performed in three Norway spruce stands and in one seed orchard. Results are presented for seed yield and 1000 seed weights. Filled seed percentages were higher for open‐pollinated families than for... more
Complete diallel crosses were performed in three Norway spruce stands and in one seed orchard. Results are presented for seed yield and 1000 seed weights. Filled seed percentages were higher for open‐pollinated families than for outcrossed full‐sib families and were lowest for selfed families. A large variation was found between the maternal parent trees for this character and a smaller variation between the paternal parents. No distinction could be made between genetic and environmental variation in filled seed percentages. Two out of 34 parents produced no viable seeds after selfing. Seeds from controlled crosses were heavier than seeds from open pollination. The maternal parent accounted for more than 75% of the total variation in 1000 seed weight. In addition, a small, but statistically significant effect of the male parent was found.
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ABSTRACT Short-term trials on cultivated soil were planted with families of Norway spruce that had shown epigenetic memory effects in early tests up to age two years. Measurements and assessments were made of phenology traits, tree... more
ABSTRACT Short-term trials on cultivated soil were planted with families of Norway spruce that had shown epigenetic memory effects in early tests up to age two years. Measurements and assessments were made of phenology traits, tree heights and stem defects until age 16 years in these trials. The memory effects of the temperature conditions during embryo development and seed maturation were confirmed for the timing of bud flush and for start and cessation of shoot elongation at age six years. The mean differences in timing of these events caused by temperature treatments were on average less than two days. They were considerably larger for families with strong effects on terminal bud set at the end of the first growing season. The memory effects did not result in a prolonged shoot growth period, nor did they affect height growth. Interaction effects expressed in adaptive traits between factorial treatments of temperature and daylength during seed production were large in the short-term trial and were still present at age nine years. The results presented demonstrate that strong memory effects observed in early tests may also be expressed in phenology traits for at least the next five growing seasons.
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... Research paper ofSkogforsk 1/95: 1-24. Edvardsen, 0. M., Johnsen, 0. & Dietrichson, J., 1996. Growth rhythm and frost hardiness in northern progeny trials with plants from Lyngdal seed orchard.(Norwegian with English summary). ...... more
... Research paper ofSkogforsk 1/95: 1-24. Edvardsen, 0. M., Johnsen, 0. & Dietrichson, J., 1996. Growth rhythm and frost hardiness in northern progeny trials with plants from Lyngdal seed orchard.(Norwegian with English summary). ... Studies in hybrid aspen. Doctor's dissertation. ...
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Research Interests: Botany, Microbiology, Plant Biology, Biology, Phenology, and 5 morePlant, Phloem, Picea abies, Plant Pathology, and Shoot
... Impacts of climate change on cold hardiness of conifers. Forfatter, H. Hänninen , Egbert Beuker , Øystein Johnsen , I. Leinonen , M. Murray , L. Sheppard , Tore Skrøppa. ... Referanse. Hänninen H., Beuker E., Johnsen, Ø., Leinonen I.,... more
... Impacts of climate change on cold hardiness of conifers. Forfatter, H. Hänninen , Egbert Beuker , Øystein Johnsen , I. Leinonen , M. Murray , L. Sheppard , Tore Skrøppa. ... Referanse. Hänninen H., Beuker E., Johnsen, Ø., Leinonen I., Murray M., Sheppard L. & Skrøppa, T. 2001. ...
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Adaptive traits in Picea abies (Norway spruce) progenies are influenced by the maternal temperatures during seed production. Here, we have extended these studies by testing the effects of maternal photoperiod and temperature on phenology... more
Adaptive traits in Picea abies (Norway spruce) progenies are influenced by the maternal temperatures during seed production. Here, we have extended these studies by testing the effects of maternal photoperiod and temperature on phenology and frost hardiness on progenies. Using eight phytotron rooms, seeds from three unrelated crosses were made in an environmental 2 x 2 factorial combination of long and short days and high and low temperatures. The progenies were then forced to cease growth rapidly at the end of the first growing season. An interactive memory effect was expressed the second growth season. Progenies from high temperature and short days, and from low temperatures and long days, started growth later in spring, ceased shoot growth later in summer, grew taller and were less frost hardy in the autumn than their full siblings from low temperatures and short days, and from high temperatures and long days. Norway spruce has developed a memory mechanism, regulating adaptive plasticity by photoperiod and temperature, which could counteract harmful effects of a rapidly changing climate.
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In order to enhance cone production in Norway spruce [Picea abies (L.) Karst] seed orchards have been established in more southerly, warmer sites in Norway. This has led to concern and some evidence that seedlings obtained from parent... more
In order to enhance cone production in Norway spruce [Picea abies (L.) Karst] seed orchards have been established in more southerly, warmer sites in Norway. This has led to concern and some evidence that seedlings obtained from parent trees grown at warmer ...
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Common garden plantations have provided data for studies of the variability in quantitative adaptive traits among and within wild populations of forest tree species. The distribution of variability among and within populations, its... more
Common garden plantations have provided data for studies of the variability in quantitative adaptive traits among and within wild populations of forest tree species. The distribution of variability among and within populations, its patterns across the landscape and relationships to environmental variables have been used to interpret the ecological basis for genetic differentiation and evolution of the species (Rehfeldt 1988, 1989,1995; Campbell et al. 1989). The studies have shown that climatic adaptation seems to be the most important component in the evolutionary process of temperate and boreal conifers. Most species show substantial variability in adaptive traits both within and among populations, even at the climatic margin of their range (Savolainen 1997). The main evolutionary forces influencing the variability patterns are natural selection, genetic drill, gene flow, mutations and phenotypic plasticity (Eriksson 1998a). The marry types of variability patterns shown by different species and their degree of adaptedness to the sites suggest that species occupying the same environment may be influenced by different evolutionary forces, see examples discussed by Eriksson (1998b). Several selective forces may even operate on the same population, some simultaneously and some at different life stages or during different seasons of the year (Eriksson 1998a). The variability patterns are therefore most likely under the influence of several evolutionary forces interacting in rather complex ways. This conclusion is supported by the rather high levels of genetic variation in survival and annual growth rhythm traits maintained in the boreal forest (Savolainen 1997), in spite of a strong directional selection against the traits.
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In order to enhance cone production in Norway spruce [Picea abies (L.) Karst] seed orchards have been established in more southerly, warmer sites in Norway. This has led to concern and some evidence that seedlings obtained from parent... more
In order to enhance cone production in Norway spruce [Picea abies (L.) Karst] seed orchards have been established in more southerly, warmer sites in Norway. This has led to concern and some evidence that seedlings obtained from parent trees grown at warmer ...
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Forests and wooded land cover 39% of the land area of Norway, with two conifer species, Picea abies and Pinus sylvestris, dominating the forest area. Twenty-five of 35 native forest tree species have their northern limit in this country.... more
Forests and wooded land cover 39% of the land area of Norway, with two conifer species, Picea abies and Pinus sylvestris, dominating the forest area. Twenty-five of 35 native forest tree species have their northern limit in this country. The genetic resources of 18 species are considered to be vulnerable or threatened either at a local or national level. Genetic information is available for 13 of the native species, with Picea abies being the species that has been most thoroughly characterised. The National Programme for Forest Genetic Resources is administered by the Norwegian Genetic Resource Centre. This programme covers four major areas: generating knowledge and monitoring processes influencing genetic resources; in situ and ex situ conservation activities; sustainable use and development of forest genetic resources; and networking, coordination and dissemination of knowledge. In situ conservation of genetic resources of forest tree species is carried out in nature reserves. Twenty-three gene conservation units, covering ten species, have been established in such reserves. Ex situ conservation of forest genetic resources is achieved through collections in arboreta and botanical gardens and in the long-term field plantations of research and breeding programmes. In addition, seed samples of selected forest tree species are stored at Svalbard Global Seed Vault. Forests in Norway are regenerated both by natural and artificial means. A revised tree breeding strategy, with emphasis on Picea abies, has been developed to improve climatic adaptation, growth and quality, without decreasing the genetic diversity in future forests or the potential for adaptation to future climatic conditions.
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Classical Mendelian inheritance assumes the existence of chromosomal genes which are transferred from the parents to the next generation in a random fashion. In a diploid plant species, the zygote is derived from the fusion of two haploid... more
Classical Mendelian inheritance assumes the existence of chromosomal genes which are transferred from the parents to the next generation in a random fashion. In a diploid plant species, the zygote is derived from the fusion of two haploid gametes, one contributed by its maternal and one by its paternal parent. These gametes were formed after a random segregation during meiosis in each parent. The fertilization of the female (egg) by the male gamete (pollen) is likewise thought to be random. Therefore, when no internal or external factors are operating, the genetic composition of the progeny population can be described with statistical precision by the laws of probability theory. Fundamental principles are regular segregation and independent assortment between different pairs of alleles (Grant 1975). Based on these assumptions a whole body of population and quantitative genetic theory has been developed for plant population changes under the evolutionary forces of natural selection, mutation, migration and drift (i.e. Falconer 1989; Hedrick 1985). The models have been verified in a large set of observational and experimental data.
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The complete diallel cross is the only mating design that provides estimates of variance components of general combining (GCA), specific combining ability (SCA), maternal and reciprocal effects, in addition to heritabilities and genetic... more
The complete diallel cross is the only mating design that provides estimates of variance components of general combining (GCA), specific combining ability (SCA), maternal and reciprocal effects, in addition to heritabilities and genetic correlations. To obtain such estimates, complete diallels were made among 10 trees in each of three natural Norway spruce populations from altitude 300 and 500 m in Norway. Nursery trials were performed with the families from these crosses and families from seeds collected from open pollination. Traits measured and analysed are seed weight, germination rate, germination percentage, terminal bud set, and seedling heights the first and second years. The seedlings from the population at origin 500 m had lower seed weight, lower heights and earlier bud set than those from the two populations from lower altitude. A considerable variation was present among families within each diallel, and the GCA variance components had the highest values and were signifi...
... Cochran, WG and GM Cox: Experimental designs. ... Years of grafting Area size ha Number Graft heights Years of of clones in 1980, m assessments Origin of clones Altitude ma .«.1. 40 -310 325--830 зга- -620 тоо- -925 < 500 Seed... more
... Cochran, WG and GM Cox: Experimental designs. ... Years of grafting Area size ha Number Graft heights Years of of clones in 1980, m assessments Origin of clones Altitude ma .«.1. 40 -310 325--830 зга- -620 тоо- -925 < 500 Seed orchards: Eloy 1969 Sauherad 1969 ...
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The complete diallel cross is the only mating design that provides estimates of variance components of general combining (GCA), specific combining ability (SCA), maternal and reciprocal effects, in addition to heritabilities and genetic... more
The complete diallel cross is the only mating design that provides estimates of variance components of general combining (GCA), specific combining ability (SCA), maternal and reciprocal effects, in addition to heritabilities and genetic correlations. To obtain such estimates, complete diallels were made among 10 trees in each of three natural Norway spruce populations from altitude 300 and 500 m in southern Norway. Seedlings from families from the diallels and open pollinations were tested in short-term tests on agricultural soil at one site at altitude 85 m until age 10 years from seed. Tree height at ages 7 and 10 years and diameter at age 10 had strongly significant GCA variance components within each population. The components for SCA and maternal effects were small and not significant, indicating low levels of non-additive genetic variation. For the days of initiation and cessation of the shoot elongation period the GCA components were dominating and had the highest heritabilit...
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Samlet sett for Norge vil klimaendringene i hovedsak virke positivt på gran ved å øke utbredelsen og produksjonsevnen. Men risikoen for klimarelaterte skader ventes å øke, særlig i lavlandet på Østlande
In the northern hemisphere proper timing of onset and cessation of growth is crucial to avoid injury from late spring frosts and early autumn frosts. Normally Norway spruce (Picea abies (L.) Karst.) has one growth flush during the growth... more
In the northern hemisphere proper timing of onset and cessation of growth is crucial to avoid injury from late spring frosts and early autumn frosts. Normally Norway spruce (Picea abies (L.) Karst.) has one growth flush during the growth season. However, in some cases a second flush is observed in young trees. The shoots resulting from the second flush are called Lammas shoots. Any delay of growth cessation may postpone the onset of hardiness development, and thus make the trees susceptible to frost injury during autumn. It is also possible that the late bud formation will affect the timing of bud burst the following spring, and thus increase the risk of spring frost injury. Frost injuries to the terminal bud can result in two or more lateral branches competing for the lead. It has also been recognized that this second, but short, elongation of the leader cause a higher number of nodal branch buds to form. These later develop into the main branch whorl that in many cases appears as ...
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Forests and wooded land cover 39% of the land area of Norway, with two conifer species, Picea abies and Pinus sylvestris, dominating the forest area. Twenty-five of 35 native forest tree species have their northern limit in this country.... more
Forests and wooded land cover 39% of the land area of Norway, with two conifer species, Picea abies and Pinus sylvestris, dominating the forest area. Twenty-five of 35 native forest tree species have their northern limit in this country. The genetic resources of 18 species are considered to be vulnerable or threatened either at a local or national level. Genetic information is available for 13 of the native species, with Picea abies being the species that has been most thoroughly characterised. The National Programme for Forest Genetic Resources is administered by the Norwegian Genetic Resource Centre. This programme covers four major areas: generating knowledge and monitoring processes influencing genetic resources; in situ and ex situ conservation activities; sustainable use and development of forest genetic resources; and networking, coordination and dissemination of knowledge. In situ conservation of genetic resources of forest tree species is carried out in nature reserves. Twe...
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Research Interests: Genetics, Plant Ecology, Biology, Agricultural Biotechnology, Plant Physiology (Biology), and 15 morePlant Molecular Biology, Gene expression, Energy Metabolism, Plant Physiology, Water Stress, Metallothionein, Transcription Factor, Real Time, Forestry Sciences, Tree Genetics, Norway Spruce, Chemical Modification, cDNA library, Reverse transcription polymerase chain reaction, and Expression pattern
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Skrgppa. T. 1984. A critical evaluation of methods available to estrmute the geizogpe x erzvironment ~nteracrion. Studia Forestalia Suecica 166. 314. ISSN 0039-3150. ISBN 91-576-1847-X. Methods to analyse genotype x environment... more
Skrgppa. T. 1984. A critical evaluation of methods available to estrmute the geizogpe x erzvironment ~nteracrion. Studia Forestalia Suecica 166. 314. ISSN 0039-3150. ISBN 91-576-1847-X. Methods to analyse genotype x environment interactions in forest tree breeding experiments are discussed and evaluated based both on empirical data and statistical and biological considerations. The joint regression analys~s is a valuable technique for analys~s. but has its limitations for generalizations and biological interpretations. It is shown that different stability parameters can give different rankings of stabihty and also that the choice of scale can influence the results of the analysis. When experiments are planted at few sites. differences between performance at pairs of sites can be plotted to identify genotypes with aberrant performance. The analysis based on genetic correlations between pairs of sites is good for characterizing test environments. It is argued that whenever possible ma...