Denne rapporten presenterer resultater fra forsøk med populasjoner fra Sør-Norge og Trøndelag og ... more Denne rapporten presenterer resultater fra forsøk med populasjoner fra Sør-Norge og Trøndelag og med provenienser fra Mellom-Europa og Finland. Både korttidsforsøk plantet på jordbruksmark og feltforsøk i skogen ble plantet. Målinger og registreringer ble gjort av høyde, tidlighet og høstskudd. Det var signifikante forskjeller i disse egenskapene både mellom provenienser, norske populasjoner og familier innen populasjoner. For de norske populasjonene var det samspill for middeltall av høyde og tidlighet i korttids- og feltforsøkene. Betydelige samspill for overlevelse og høyde ble funnet mellom provenienser og lokaliteter for feltforsøk som bare ligger noen få kilometer fra hverandre. Disse samspillene kom sannsynligvis på grunn av forskjeller i det lokale temperaturklimaet. Kunnskap om samspill og om de avhenger av geografiske og klimatiske faktorer, er viktig både for valg av provenienser og for planteforedlingen for gran.publishedVersio
Skog er viktig i Norge. Det er uttalt politisk vilje til å styrke skogens bidrag for økonomisk ve... 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...
Complete diallel crosses were performed in three Norway spruce stands and in one seed orchard. Re... 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.
Scandinavian Journal of Forest Research, Mar 7, 2022
ABSTRACT Short-term trials on cultivated soil were planted with families of Norway spruce that ha... 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.
... Research paper ofSkogforsk 1/95: 1-24. Edvardsen, 0. M., Johnsen, 0. & Dietrichson, J., 1... 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. ...
We have compared bud set and frost hardiness among Norway spruce (Piceas abies (L.) Karst.) prove... more We have compared bud set and frost hardiness among Norway spruce (Piceas abies (L.) Karst.) provenances and families in two cold-acclimation regimes in a phytotron; low light intensity and high night temperatures (LL-HNT), and high light intensity and low night temperatures (HL-LNT) under shortening day lengths. Nine provenances from 59-66°N and altitude 100-700 m within Norway, and nine open-pollinated families from a single stand (61°N, 270 m elevation) were used. Both provenances and families started bud set and frost hardening earlier in LL-HNT than in HL-LNT. Correlations between the same trait expressed in two regimes were high for both bud set and hardiness at the provenance level and slightly lower at the family level. The variation among family means in bud set and hardiness was large. The differences found between the family extremes were up to 75% of those found between provenance extremes. The relationship between bud set and frost hardiness was strong among the provenance means within both environments (r = 0.92) but weak for the families (r = 0.22-0.44). Causal factors influencing phenotypic variation within traits and covariation among traits may differ for provenances and families within stands. The strong relationships among traits that are found at the provenance level cannot be generalized to the levels of families or clones. Résumé : Les auteurs ont comparé l'aoûtement et la résistance au froid de plusieurs provenances et descendances d'épinette de Norvège sous deux régimes d'acclimatation au froid en chambre de croissance : un régime de faible intensité lumineuse associée à de hautes températures nocturnes (LL-HNT) et un régime de forte intensité lumineuse et de basses températures nocturnes (HL-LNT). Les deux régimes ont été soumis à des photopériodes décroissantes. Pour ce faire, neuf provenances norvégiennes couvrant de 59 à 66°N et de 100 à 700 m d'altitude ainsi que neuf descendances issues de pollinisation libre et provenant d'un même peuplement (61°N, altitude de 270 m) ont été utilisées. Tant les provenances que les descendances ont amorcé leur aoûtement et leur endurcissement au froid plus tôt avec le régime LL-HNT qu'avec HL-LNT. Au niveau des provenances, les corrélations entre régimes pour le même caractère étaient élevées à la fois pour l'aoûtement et la résistance au froid. Ces corrélations étaient légèrement plus faibles au niveau familial. Les différences pour l'aoûtement et la résistance au froid étaient fortes entre les descendances et représentaient jusqu'à 75% des différences entre les valeurs extrêmes observées chez les provenances. La relation entre l'aoûtement et la résistance au froid était forte parmi les moyennes des provenances quel que soit le régime environnemental (r = 0,92). Cependant, cette relation était plus faible pour les familles (r variant de 0,22 à 0,44). Il en découle que les facteurs de causalité affectant la variation phénotypique pour chacun des caractères ainsi que la covariation entre ces derniers pourraient être différents pour les provenances et pour les descendances à l'intérieur d'un même peuplement. Les fortes relations observées entre caractères au niveau des provenances ne peuvent être généralisées au niveau familial ou clonal.
Ceratocystis polonica and Heterobasidion parviporum are important fungal pathogens in Norway spru... more Ceratocystis polonica and Heterobasidion parviporum are important fungal pathogens in Norway spruce (Picea abies). Tree susceptibility to these pathogens with respect to phenology was studied using artificial fungal inoculations at six stages of bud development, and assessed by measuring phloem necroses in the stems of 2-and 8-year-old trees. Tree capacity for resistance was assessed by measuring phloem nonstructural carbohydrates at each stage. Phloem necroses were significantly larger in trees with fungal versus control inoculations and increased significantly over time. Changes in nonstructural carbohydrates occurred in the trees; a significant decline in starch and a slight but significant increase in total sugars occurred over time. These results suggest that susceptibility to fungal pathogens and carbohydrate levels in the stems of the trees were related to fine-scale changes in bud development. A trade-off may occur between allocation of starch (the major fraction of the stem carbohydrate pool) to bud development ⁄ shoot growth versus defence of the stem. Previous tests of plant defence hypotheses have focused on herbivory on plants growing under different environmental conditions, but the role of phenology and the effect of pathogens are also important to consider in understanding plant resource allocation patterns.
... Impacts of climate change on cold hardiness of conifers. Forfatter, H. Hänninen , Egbert Beuk... 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. ...
The root rot pathogens in Norway spruce (Picea abies) Heterobasidion ssp. cause substantial loss ... more The root rot pathogens in Norway spruce (Picea abies) Heterobasidion ssp. cause substantial loss in carbon sequestered in forest and economic revenue for forest owners. To facilitate strategic breeding planning for increased resistance against this pathogen in particular, the blue stain fungus Endoconidiophora polonica, growth and wood quality traits (wood density and spiral grain), we estimated additive genetic parameters, correlations and the potential response from selection. Parameters were estimated from a progeny trial series established at two sites (25 years from planting) and their parents in a seed orchard (43 years from grafting). A standard half-sib analysis based on progenies and a parent-offspring regression was used for estimation of heritabilities. Resistance against the pathogens was measured as lesion length under bark after inoculations in phloem. Heritability values varied with site and estimation procedure from 0.06 to 0.33, whereas the phenotypic variance (as CV P) is high and fairly stable around 40-50 %. Heritability values for wood density and spiral grain in the same material varied from 0.32 to 0.63. The highest heritability values were generally obtained from parent-offspring regression. There is no evidence of resistance traits being genetically correlated with growth or wood quality traits. Wood density is negatively correlated with stem diameter. Implications for breeding are discussed.
In 1989, identical crosses (2-3 females within males) were performed with Picea abies (L.) Karst.... more In 1989, identical crosses (2-3 females within males) were performed with Picea abies (L.) Karst. in a greenhouse seed orchard at Biri nursery and in an outdoor seed orchard at Huse, 32 km north of Biri. Pollination began 17 days earlier in the greenhouse than outdoors at Huse. The potted grafts in the greenhouse were moved outdoors when the seed cones were no longer receptive. Twelve full-sib family pairs (Biri and Huse) from these crosses were grown in a phytotron and tested for height and autumn frost hardiness during their first growing season. No significant difference was found between the indoor (Biri) and outdoor (Huse) progenies for height growth. However, the progenies from the greenhouse seed orchard were significantly more susceptible to frost than their full-sibs from the outdoor seed orchard. There was no significant interaction between males and the flowering environment, but a significant female × flowering environment interaction was present as a result of greater differences in frost hardiness between progenies from females in the greenhouse seed orchard than in the outdoor seed orchard. Although seeds from the outdoor seed orchard generally had a greater biomass than seeds from the greenhouse seed orchard, the difference in seed weight did not explain the difference in frost hardiness. We hypothesize that temperature and photoperiod during pollination and fertilization affect the frost hardiness of the progenies.
Adaptive traits in Picea abies (Norway spruce) progenies are influenced by the maternal temperatu... 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.
Scandinavian Journal of Forest Research, May 1, 2001
In order to enhance cone production in Norway spruce [Picea abies (L.) Karst] seed orchards have ... 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 ...
Several independent tests have shown that climate and weather during sexual reproduction influenc... more Several independent tests have shown that climate and weather during sexual reproduction influence the adaptive properties of the Picea abies progenies. This phenomenon is expressed in seed orchards established by moving parent trees, propagated as grafts, from north to south, from high to low elevation, or from outdoor to indoor greenhouse conditions. The progenies exhibit delayed flushing in the spring, later growth cessation of leader shoots in the summer, delayed bud-set, higher frequency of lammas shoots and delayed development of frost hardiness in the autumn compared to progenies reproduced in the colder native environment. The altered performance is persistent. We have found no effect on progenies of photoperiod and temperature treatments given to the males during meiosis and pollen production. However, when crosses were made in early spring (March), inside a heated greenhouse (short day, high temperature), the progenies are less frost hardy during cold acclimation than progenies from identical crosses performed in late spring (May ; long day high temperature) in the greenhouse. The most hardy offspring were from crosses performed under outdoor conditions in May (long day, low temperature). These results indicate that some stages in reproduction, such as female meiosis, pollen tube growth, syngamy and early embryo development, are sensitive to temperature and/or photoperiod which then alter the phenotypic performance of the offspring. The most likely explanation is the existence of a regulatory mechanism affecting the expression of genes controlling adaptive traits. If this is true, it must have implications for the genetic interpretation of provenance differences in Norway spruce.
Common garden plantations have provided data for studies of the variability in quantitative adapt... 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.
In order to enhance cone production in Norway spruce [Picea abies (L.) Karst] seed orchards have ... 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 ...
Denne rapporten presenterer resultater fra forsøk med populasjoner fra Sør-Norge og Trøndelag og ... more Denne rapporten presenterer resultater fra forsøk med populasjoner fra Sør-Norge og Trøndelag og med provenienser fra Mellom-Europa og Finland. Både korttidsforsøk plantet på jordbruksmark og feltforsøk i skogen ble plantet. Målinger og registreringer ble gjort av høyde, tidlighet og høstskudd. Det var signifikante forskjeller i disse egenskapene både mellom provenienser, norske populasjoner og familier innen populasjoner. For de norske populasjonene var det samspill for middeltall av høyde og tidlighet i korttids- og feltforsøkene. Betydelige samspill for overlevelse og høyde ble funnet mellom provenienser og lokaliteter for feltforsøk som bare ligger noen få kilometer fra hverandre. Disse samspillene kom sannsynligvis på grunn av forskjeller i det lokale temperaturklimaet. Kunnskap om samspill og om de avhenger av geografiske og klimatiske faktorer, er viktig både for valg av provenienser og for planteforedlingen for gran.publishedVersio
Skog er viktig i Norge. Det er uttalt politisk vilje til å styrke skogens bidrag for økonomisk ve... 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...
Complete diallel crosses were performed in three Norway spruce stands and in one seed orchard. Re... 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.
Scandinavian Journal of Forest Research, Mar 7, 2022
ABSTRACT Short-term trials on cultivated soil were planted with families of Norway spruce that ha... 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.
... Research paper ofSkogforsk 1/95: 1-24. Edvardsen, 0. M., Johnsen, 0. & Dietrichson, J., 1... 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. ...
We have compared bud set and frost hardiness among Norway spruce (Piceas abies (L.) Karst.) prove... more We have compared bud set and frost hardiness among Norway spruce (Piceas abies (L.) Karst.) provenances and families in two cold-acclimation regimes in a phytotron; low light intensity and high night temperatures (LL-HNT), and high light intensity and low night temperatures (HL-LNT) under shortening day lengths. Nine provenances from 59-66°N and altitude 100-700 m within Norway, and nine open-pollinated families from a single stand (61°N, 270 m elevation) were used. Both provenances and families started bud set and frost hardening earlier in LL-HNT than in HL-LNT. Correlations between the same trait expressed in two regimes were high for both bud set and hardiness at the provenance level and slightly lower at the family level. The variation among family means in bud set and hardiness was large. The differences found between the family extremes were up to 75% of those found between provenance extremes. The relationship between bud set and frost hardiness was strong among the provenance means within both environments (r = 0.92) but weak for the families (r = 0.22-0.44). Causal factors influencing phenotypic variation within traits and covariation among traits may differ for provenances and families within stands. The strong relationships among traits that are found at the provenance level cannot be generalized to the levels of families or clones. Résumé : Les auteurs ont comparé l'aoûtement et la résistance au froid de plusieurs provenances et descendances d'épinette de Norvège sous deux régimes d'acclimatation au froid en chambre de croissance : un régime de faible intensité lumineuse associée à de hautes températures nocturnes (LL-HNT) et un régime de forte intensité lumineuse et de basses températures nocturnes (HL-LNT). Les deux régimes ont été soumis à des photopériodes décroissantes. Pour ce faire, neuf provenances norvégiennes couvrant de 59 à 66°N et de 100 à 700 m d'altitude ainsi que neuf descendances issues de pollinisation libre et provenant d'un même peuplement (61°N, altitude de 270 m) ont été utilisées. Tant les provenances que les descendances ont amorcé leur aoûtement et leur endurcissement au froid plus tôt avec le régime LL-HNT qu'avec HL-LNT. Au niveau des provenances, les corrélations entre régimes pour le même caractère étaient élevées à la fois pour l'aoûtement et la résistance au froid. Ces corrélations étaient légèrement plus faibles au niveau familial. Les différences pour l'aoûtement et la résistance au froid étaient fortes entre les descendances et représentaient jusqu'à 75% des différences entre les valeurs extrêmes observées chez les provenances. La relation entre l'aoûtement et la résistance au froid était forte parmi les moyennes des provenances quel que soit le régime environnemental (r = 0,92). Cependant, cette relation était plus faible pour les familles (r variant de 0,22 à 0,44). Il en découle que les facteurs de causalité affectant la variation phénotypique pour chacun des caractères ainsi que la covariation entre ces derniers pourraient être différents pour les provenances et pour les descendances à l'intérieur d'un même peuplement. Les fortes relations observées entre caractères au niveau des provenances ne peuvent être généralisées au niveau familial ou clonal.
Ceratocystis polonica and Heterobasidion parviporum are important fungal pathogens in Norway spru... more Ceratocystis polonica and Heterobasidion parviporum are important fungal pathogens in Norway spruce (Picea abies). Tree susceptibility to these pathogens with respect to phenology was studied using artificial fungal inoculations at six stages of bud development, and assessed by measuring phloem necroses in the stems of 2-and 8-year-old trees. Tree capacity for resistance was assessed by measuring phloem nonstructural carbohydrates at each stage. Phloem necroses were significantly larger in trees with fungal versus control inoculations and increased significantly over time. Changes in nonstructural carbohydrates occurred in the trees; a significant decline in starch and a slight but significant increase in total sugars occurred over time. These results suggest that susceptibility to fungal pathogens and carbohydrate levels in the stems of the trees were related to fine-scale changes in bud development. A trade-off may occur between allocation of starch (the major fraction of the stem carbohydrate pool) to bud development ⁄ shoot growth versus defence of the stem. Previous tests of plant defence hypotheses have focused on herbivory on plants growing under different environmental conditions, but the role of phenology and the effect of pathogens are also important to consider in understanding plant resource allocation patterns.
... Impacts of climate change on cold hardiness of conifers. Forfatter, H. Hänninen , Egbert Beuk... 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. ...
The root rot pathogens in Norway spruce (Picea abies) Heterobasidion ssp. cause substantial loss ... more The root rot pathogens in Norway spruce (Picea abies) Heterobasidion ssp. cause substantial loss in carbon sequestered in forest and economic revenue for forest owners. To facilitate strategic breeding planning for increased resistance against this pathogen in particular, the blue stain fungus Endoconidiophora polonica, growth and wood quality traits (wood density and spiral grain), we estimated additive genetic parameters, correlations and the potential response from selection. Parameters were estimated from a progeny trial series established at two sites (25 years from planting) and their parents in a seed orchard (43 years from grafting). A standard half-sib analysis based on progenies and a parent-offspring regression was used for estimation of heritabilities. Resistance against the pathogens was measured as lesion length under bark after inoculations in phloem. Heritability values varied with site and estimation procedure from 0.06 to 0.33, whereas the phenotypic variance (as CV P) is high and fairly stable around 40-50 %. Heritability values for wood density and spiral grain in the same material varied from 0.32 to 0.63. The highest heritability values were generally obtained from parent-offspring regression. There is no evidence of resistance traits being genetically correlated with growth or wood quality traits. Wood density is negatively correlated with stem diameter. Implications for breeding are discussed.
In 1989, identical crosses (2-3 females within males) were performed with Picea abies (L.) Karst.... more In 1989, identical crosses (2-3 females within males) were performed with Picea abies (L.) Karst. in a greenhouse seed orchard at Biri nursery and in an outdoor seed orchard at Huse, 32 km north of Biri. Pollination began 17 days earlier in the greenhouse than outdoors at Huse. The potted grafts in the greenhouse were moved outdoors when the seed cones were no longer receptive. Twelve full-sib family pairs (Biri and Huse) from these crosses were grown in a phytotron and tested for height and autumn frost hardiness during their first growing season. No significant difference was found between the indoor (Biri) and outdoor (Huse) progenies for height growth. However, the progenies from the greenhouse seed orchard were significantly more susceptible to frost than their full-sibs from the outdoor seed orchard. There was no significant interaction between males and the flowering environment, but a significant female × flowering environment interaction was present as a result of greater differences in frost hardiness between progenies from females in the greenhouse seed orchard than in the outdoor seed orchard. Although seeds from the outdoor seed orchard generally had a greater biomass than seeds from the greenhouse seed orchard, the difference in seed weight did not explain the difference in frost hardiness. We hypothesize that temperature and photoperiod during pollination and fertilization affect the frost hardiness of the progenies.
Adaptive traits in Picea abies (Norway spruce) progenies are influenced by the maternal temperatu... 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.
Scandinavian Journal of Forest Research, May 1, 2001
In order to enhance cone production in Norway spruce [Picea abies (L.) Karst] seed orchards have ... 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 ...
Several independent tests have shown that climate and weather during sexual reproduction influenc... more Several independent tests have shown that climate and weather during sexual reproduction influence the adaptive properties of the Picea abies progenies. This phenomenon is expressed in seed orchards established by moving parent trees, propagated as grafts, from north to south, from high to low elevation, or from outdoor to indoor greenhouse conditions. The progenies exhibit delayed flushing in the spring, later growth cessation of leader shoots in the summer, delayed bud-set, higher frequency of lammas shoots and delayed development of frost hardiness in the autumn compared to progenies reproduced in the colder native environment. The altered performance is persistent. We have found no effect on progenies of photoperiod and temperature treatments given to the males during meiosis and pollen production. However, when crosses were made in early spring (March), inside a heated greenhouse (short day, high temperature), the progenies are less frost hardy during cold acclimation than progenies from identical crosses performed in late spring (May ; long day high temperature) in the greenhouse. The most hardy offspring were from crosses performed under outdoor conditions in May (long day, low temperature). These results indicate that some stages in reproduction, such as female meiosis, pollen tube growth, syngamy and early embryo development, are sensitive to temperature and/or photoperiod which then alter the phenotypic performance of the offspring. The most likely explanation is the existence of a regulatory mechanism affecting the expression of genes controlling adaptive traits. If this is true, it must have implications for the genetic interpretation of provenance differences in Norway spruce.
Common garden plantations have provided data for studies of the variability in quantitative adapt... 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.
In order to enhance cone production in Norway spruce [Picea abies (L.) Karst] seed orchards have ... 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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