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Silva Fennica 1926-1997
Acta Forestalia Fennica

Articles containing the keyword 'seeds'

Category: Article

article id 5458, category Article
Jaroslaw Burczyk, Grzegorz Kosiński, Andrzej Lewandowski. (1991).  . Silva Fennica vol. 25 no. 4 article id 5458.
English title: Mating pattern and empty seed formation in relation to crown level of Larix decidua (Mill.) clones.
Keywords: seeds; crown; Larix decidua; mating systems; genetic load; grafting
Abstract | View details | Full text in PDF | Author Info

The mating system was analysed in the upper and lower crown of two groups of European larch (Larix decidua Mill.) clones divided according to the percentage of full seeds in the upper and lower crown parts. The overall multilocus estimate of outcrossing rate (t) was calculated to be 0.929. The differences of outcrossing rates between crown levels and clonal groups respectively were not statistically significant. The t estimates were greater for the upper crown level and for clones with higher percentage of full seeds in the upper crown level. However, among all observations there was no correlation between outcrossing rates and percentages of full seeds for particular crown levels and groups of clones. Observed similarity of outcrossing among grafts of the same clones may indicate genetic control of self-fertilization rate in individual European larch. 

The PDF includes an abstract in Finnish.

  • Burczyk, E-mail: jb@mm.unknown (email)
  • Kosiński, E-mail: gk@mm.unknown
  • Lewandowski, E-mail: al@mm.unknown
article id 5364, category Article
Urban Bergsten. (1988). Invigoration and IDS-sedimentation of Pinus sylvestris seeds from northern Finland. Silva Fennica vol. 22 no. 4 article id 5364.
Keywords: Pinus sylvestris; germination; Scots pine; northern Finland; seed quality; elimination of non-productive seeds; invigoration of seeds
Abstract | View details | Full text in PDF | Author Info

In Northern Finland as well as in Northern Sweden there is a shortage of high-quality Scots pine (Pinus sylvestris L.) seeds, mostly due to unsuitable temperatures during the development and maturation of cones and seeds. Methods have been developed for elimination of non-productive seeds and for invigoration of seeds. In the present work, these methods were tested on poorly developed seed lot from Rovaniemi, Northern Finland (66°15’–66°30’; 180 m a.s.l.). The seeds were conditioned using the following treatments:

1. PREVAC method (5 min, 97 kPa below atmospheric pressures) for removal of mechanically damaged seeds (7%)

2. Invigoration using incubation at controlled moisture content (30% f.w) and continuous air supply, for 14 days at 5°C.

3. Additional water supply for 16 hours at 5°C.

4. Drying in dehumidified air until a near maximum difference in density between viable and dead seeds was obtained

5. Separation in a sedimentation flume to achieve a gradient of fractions of different germination rate and capacity.

The treatments resulted in an improvement of germination percentage from 33 to about 95% and a reduction in mean germination time from 8.8 days to 6 days if the control and the best fractions (32% seeds) were compared.

  • Bergsten, E-mail: ub@mm.unknown (email)
article id 5071, category Article
Martti Ryynänen. (1980). X-ray radiography of ageing Scots pine seeds. Silva Fennica vol. 14 no. 1 article id 5071.
Keywords: Pinus sylvestris; germination; Scots pine; storage; seeds; quality of seeds; X-ray radiography; X-ray contrast radiography
Abstract | View details | Full text in PDF | Author Info

Soft X-ray radiation (Grenz rays) has been used in the X-ray radiography of seeds. It is based on the principle that the different parts of the seed absorb X-rays to a slightly varying extent. Empty seeds and empty regions in the seeds appears as dark areas on the film. X-ray radiography without staining and X-ray contrast radiography were compared to study the stored seeds of Scots pine (Pinus sylvestris L.). The results were compared with the results of germination in a Jacobsen germinator according to ISTA norms.

Normal X-ray radiography gave too good estimates of germinative capacity of the seeds, and was shown to suit only when it is used to study fully ripe seeds which have recently been collected in an undamaged condition. The results of X-ray contrast radiography when barium chloride was used as the stain, however, followed closely the germination results.

The PDF includes a summary in Finnish.

  • Ryynänen, E-mail: mr@mm.unknown (email)
article id 4963, category Article
Tapio Lehtiniemi. (1977). Männyn ja kuusen siementen gammasäteilyherkkyyteen vaikuttavista tekijöistä. Silva Fennica vol. 11 no. 1 article id 4963.
English title: Factors affecting gamma-irradiation sensitivity of Scots pine and Norway spruce.
Original keywords: kuusi; mänty; alkuperä; itäminen; siemenet; säteilytys
English keywords: Pinus sylvestris; Norway spruce; Picea abies; germination; Scots pine; progeny; seeds; radiation
Abstract | View details | Full text in PDF | Author Info

This study, comprising three experiments, aims to determine the effect of the geographical origin of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) seeds, and the duration of the time lag between the moisture treatment and subsequent irradiation on the gamma-irradiation sensitivity of seeds.

The studies showed that the greater the irradiation dose seeds were subjected to the slower the rate of germination. In general, small radiation doses (250–1,000 rad) had a stimulating effect and the final germination percentage (36–40 days) increased. However, when the level was further increased, the germination percentage decreased. Air-dry and moistened seeds withstood irradiation better than others. In a study with moistened seeds from different geographical sources, pine and spruce seeds from Northern Finland were less able to withstand irradiation than those originating from the south.

The PDF includes a summary in English.

  • Lehtiniemi, E-mail: tl@mm.unknown (email)
article id 4930, category Article
Tapio Lehtiniemi. (1976). Ionisoivan säteilyn vaikutus varastokuivien ja liotettujen metsäpuiden siementen idäntään ja taimien alkukehitykseen. Silva Fennica vol. 10 no. 1 article id 4930.
English title: Effect of ionizing radiation on the germination of storage-dry and soaked forest tree seeds and on the initial development of seedlings.
Original keywords: metsänjalostus; itäminen; siemenet; säteilytys; mutaatiot
English keywords: Pinus sylvestris; Betula pendula; Picea abies; germination; Betula pubescens; Alnus glutinosa; Alnus incana; seeds; forest tree breeding; radiation; mutations
Abstract | View details | Full text in PDF | Author Info

The study was carried out in order to find out the changes taking place in germination of seeds in certain tree species as a function of gamma irradiation, the height growth of the seedlings produced and the types of phenotypic mutants possibly found in the generation that had received radiation. The tree species studied were Pinus sylvestris L., Picea abies (L.) H. Karst., Betula verrucosa (Betula pendula Roth), B. Pubescens Ehrh., Alnus glutinosa (L.) Gaertn. and Alnus incana (L.) Moench.

Soaked seeds that had received a rather small dose of radiation germinated usually better than storage-dry seeds, B. pubescens being an exception. The damages observed in germination, height growth and the relative number of mutants were greater the higher the irradiation doses. The LD50 dose (germination, 28 days) was as follows in the case of the different tree species (storage dry/soaked): P. Sylvestris 1,500-2,000/2500-3,000, P. abies 1,000-1,500/4,000-4,500, B. pendula 9,500-10,000/7,000-7,500, B. pubescens >10,000/7,500-8,000 and A. Glutinosa 10,000/8,500-9,000 rad. Mass production of different mutants of deciduous trees for ornamental purposes, for example, appears to be easy using gamma-irradiation. On the other hand, the possibility of increasing tree growth remains open for further study.

The PDF includes a summary in English.

  • Lehtiniemi, E-mail: tl@mm.unknown (email)
article id 4910, category Article
Erkki Lähde, Katri Pahkala. (1974). Havupuiden siemenen kehitys ja itäminen kirjallisuuden valossa. Silva Fennica vol. 8 no. 4 article id 4910.
English title: Development and germination of the seeds of conifers according to literature.
Original keywords: kylvö; havupuut; itäminen; esi-idätysmenetelmä; kukkiminen; siementen kehitys; pölytys
English keywords: germination; flowering; conifers; pollination; seeds; sowing; seeding; development of seeds; pre-germination method
Abstract | View details | Full text in PDF | Author Info

The aim of the present study was to collect information presented in literature concerning the development and germination of the seeds of coniferous trees with special reference to those species which thrive in the conditions prevailing in Finland. Along with the increase in the importance of direct seeding as a silvicultural means in Northern Finland, there is a growing demand for methods by means of which the germination of seeds could be promoted. According to the results obtained from previous studies, such a method can be found, provided that a practically usable and reliable pre-germination method is developed.

The PDF includes a summary in English.

  • Lähde, E-mail: el@mm.unknown (email)
  • Pahkala, E-mail: kp@mm.unknown
article id 4832, category Article
Paavo Yli-Vakkuri, Pentti K. Räsänen. (1971). Siementen peittämisen ja kylvökohdan polkaisun vaikutus männyn ruutukylvön tulokseen. Silva Fennica vol. 5 no. 1 article id 4832.
English title: The influence of covering and tramping the seeds into the soil on the success of spot sowing of Scots pine.
Original keywords: kylvö; mänty; metsänviljely; taimettuminen; itäminen; kylvösyvyys; siementen suojaus; ruutukylvö
English keywords: Pinus sylvestris; germination; Scots pine; sowing; artificial regeneration; covering of the seeds; stocking with seedlings
Abstract | View details | Full text in PDF | Author Info

This paper reports spot sowing experiments of Scots pine (Pinus sylvestris L.). The seeds were either covered with coarse sand, tramped in the substrate or sowed without any covering, 30 seeds in each treatment in 70 replications. The site was of Vaccinium type with sandy soil. The germination percentage was 81 and 91 on the respective years. The development of seedlings was observed for 3–4 years.

The results indicate that both tramping and covering the seeds to some extent increased the number of seedlings and improved the early development. The highest numbers of seedlings were recorded in the first growing season, after which there was 23 seedlings/100 seeds in the uncovered spots, 27 seedlings in the covered spots and 31 seedlings in the tramped spots in the experiment sowed in 1965.

Mortality of the seedlings was highest between the first and second growing season, and empty spots increased with the time. There was no difference in mortality between the sowing methods, but the number of seedlings after first growing season affected the result. Under favourable conditions four seedlings per spot seemed enough to secure the survival of minimum one seedling per spot during the three first growing seasons. In poor conditions seven seedlings was needed.

The PDF includes a summary in English.

  • Yli-Vakkuri, E-mail: py@mm.unknown (email)
  • Räsänen, E-mail: pr@mm.unknown
article id 4810, category Article
Pentti Solin. (1970). Kuusen käpyjen säilyttäminen jäähdyttämössä ja sen vaikutus niistä saatavan siemenen itävyyteen. Silva Fennica vol. 4 no. 1 article id 4810.
English title: Cold storage of Norway spruce cones and its effect on seed viability.
Original keywords: kuusi; varastointi; siemenet; itävyys; kävyt; kylmävarasto
English keywords: Norway spruce; Picea abies; germination; storage; viability; seeds; cones; cold storage
Abstract | View details | Full text in PDF | Author Info

The aim of the study was to establish how the cold storage of cones of Norway spruce (Picea abies (L.) H. Karst.) affects the viability of the seeds and the percentage ratio in 7 days. A parallel study was made of the longevity of seed in barn-stored cones subject to weather fluctuations and the longevity of seed extracted immediately and stored in the conventional way in an air-tight container. The cones were collected near Kuopio in Central Finland and near Tampere.

The viability and germination rate of the control sample was constant throughout the storage period. This storage method proved the best. The viability of seeds kept in cones declined in cold storage after 3 ½ months. The cones collected in Tampere were damaged by Laspeyresia strobilella, which affected the viability of the seeds.

The viability of seeds stored in cones in a barn had not weakened by the end of May, however, they deteriorated during the summer, as did the seeds stored in cones in the cold storage. Viability of the seeds was still 94% in October. The germination rate was constant in each lot up to the end of May, after which it decreased to 81.7–86.1% in October.

The results show that healthy spruce cones can be stored in paper sacks in a single layer in cold storage and in an ordinary barn for several months without it affecting the viability of the seeds.

The PDF includes a summary in English.

  • Solin, E-mail: ps@mm.unknown (email)
article id 4803, category Article
Kari Löyttyniemi. (1969). Männyn ja kuusen siemenien esikäsittelyn vaikutuksesta itämiseen ja taimien alkukehitykseen kasvihuoneoloissa. Silva Fennica vol. 3 no. 3 article id 4803.
English title: The effect of treatment of Scots pine and Norway spruce seeds on their germination and the early development of the seedlings.
Original keywords: kuusi; mänty; taimettuminen; itäminen; esikäsittely; siemenet; taimikuolleisuus
English keywords: Pinus sylvestris; Norway spruce; Picea abies; germination; Scots pine; seedlings; seeds; treatment of seeds; mortality of seedlings
Abstract | View details | Full text in PDF | Author Info

The aim of this study was to establish the need of treatment of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) seeds to be sown in greenhouse. 3 x 100 seeds of each treatment (soaking in water, treatment with Pb3O4, treatment with tiram-containing coating substance) were sown in a glasshouse on a fertilized garden peat, and covered with peat layer of 6 mm thickness. The development of seedlings was followed for 100 days before the final measurement.

Soaking the seeds with water made germination somewhat faster. In spruce the germination percentage increased, but the opposite was observed in pine. No difference could be observed between the results from soaking with acid water from peat soil and lake water. Drying the soaked seeds for a week before sowing had no harmful influence on the germination or the early development of the seedlings. Treatment with Pb3O4 did not affect the germination speed or the seedling percentage of pine or spruce, but increased the germination percentage of spruce. Coating decreased germination and seedling percentages in pine. However, the differences between the treatments were so small that their practical significance is negligible.

Germination of both the species initiated on an average in 8 days, and 16 days after sowing 80% of the seeds had germinated. Seedling mortality was about 10% of the total number of seedlings, the most common reason being damping-off.

The PDF includes a summary in English.

  • Löyttyniemi, E-mail: kl@mm.unknown (email)

Category: Article

article id 7158, category Article
Olavi Huuri. (1965). Männyn- ja kuusenkäpyjen varastoinnin vaikutus niistä saatavan siemenen itävyyteen. Silva Fennica vol. 78 no. 5 article id 7158.
English title: The effects of storage in cones on the viability of pine and spruce seeds.
Original keywords: kuusi; mänty; itävyys; kävyt; siemenkeräys; käpyjen varastointi; metsäpuiden siemenet; siementen varastointi; karistus; itämiskyky
English keywords: Pinus sylvestris; Norway spruce; Picea abies; Scots pine; cones; seeds of forest trees; seed extraction; storage of cones; storage of seeds; germinative capacity
Abstract | View details | Full text in PDF | Author Info

Seed storing experiments with cones of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) were conducted in Oitti seed extracting plant in Southern Finland from February to December 1955. The pine cones were stores for 267 and the spruce coned for 304 days. In four of the storage methods the cones were packed in sacks and another four in wooden boxes. Sample of cones were taken once a month, seeds were extracted and the germinative capacity was tested. The remaining extracted seeds were placed in storage, and in January 1956 moved to cold seed cellar until 1962, when the viability of the seeds was tested.

According to the results, cleaned pine cones can be stores for at least nine months using almost all methods of storage which are commonly used at our seed traction plants, without hazarding the usability of the seeds. The seeds in spruce cones, however, seemed to be more sensitive to conditions during the storage. The germinative capacity of the spruce seeds began to decrease after the beginning of May. Later the seeds were infected with mould, which increased towards the end of the experiment.

Thus, preservation of the germinative capacity of the seeds of pine and spruce requires storage in different conditions. The results suggest that extraction of spruce seeds should be finished during the cold winter months. It seems that seed in the cones of pine and spruce endure storage in piles of paper or cloth sacks at least as well as in wooden boxes. Occasional warming of the storage, snow and foreign material among the cones and an over meter thick cone layer decreased the germinative capacity of spruce seeds during spring and summer. Spruce seeds that had been extracted immediately after collecting of the cones preserved their germinative capacity well during an eight years storage period.

The PDF includes a summary in English.

  • Huuri, E-mail: oh@mm.unknown (email)
article id 7128, category Article
Paavo Yli-Vakkuri. (1961). Emergence and initial development of tree seedlings on burnt-over forest land. Silva Fennica vol. 74 no. 1 article id 7128.
Keywords: Pinus sylvestris; Norway spruce; Picea abies; germination; regeneration; Scots pine; seeds; prescribed burning; sowing; seeding
Abstract | View details | Full text in PDF | Author Info

Prescribed burning has been used in regeneration areas in Finland as a method to treat the humus layer and creating more favourable chemical, physical and biological conditions for the seedlings. At the same time, fire clears away seedlings and shoots of unwanted trees and other vegetation. Direct sowing or planting, mostly Scots pine (Pinus sylvestris L.), seldom natural regeneration, is used. In this paper, the initial stages of the formation of a new tree generation of Scots pine and Norway spruce (Picea abies (L.) Karst.) on prescribed burned areas is studied in Central Finland in 1956–1960.

The burned area remains almost without vegetation for about two growing seasons. Conditions on a burned area which has not been tiled are very unfavourable for germination of seeds of coniferous and deciduous trees. On the other hand, shoots of deciduous trees occur soon after burning. Conditions for regeneration were found to be better 3–5 years after burning. Removal of humus layer in spots improved regeneration. However, the patches facilitated also natural regeneration of Norway spruce and especially birch (Betula sp.), which compete with Scots pine seedlings.

Continuous rainy periods improved the germination of Scots pine and Norway spruce seeds sown on the humus layer. Pine and spruce developed more rapidly on the exposed soil, however, young seedlings were easily destroyed. Seed eaters destroyed the pine and spruce seeds sown on the humus layer of newly burned areas completely or almost completely. The viability of pine seeds sown on the burned humus layer did not decrease for three weeks, but the viability greatly weakened after six or more weeks. Spruce seeds lost their viability faster than pine seeds.

The PDF includes a summary in Finnish.

  • Yli-Vakkuri, E-mail: py@mm.unknown (email)
article id 7486, category Article
Paavo Yli-Vakkuri. (1959). Siemensiipien hankaajista ja niiden vaikutuksesta siemenen itävyyteen. Silva Fennica vol. 68 no. 4 article id 7486.
English title: On machines for abrading seed wings and their influence on the germinative capacity of the seed.
Original keywords: kuusi; mänty; laitteet; metsäpuiden siemenet; karistamot; siemensiivet; siemensiipien hankaajat
English keywords: Pinus sylvestris; Norway spruce; Picea abies; Socts pine; seeds of forest trees; seed extraction; seed wings
Abstract | View details | Full text in PDF | Author Info

This paper deals with two machines designed for abrading seed wings, and their influence on the germinative capacity of seed of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.). Both machines are commonly used in Finland.

The results of the study indicate that the act of abrading may cause slight or even serious injuries to the seed. Slight injuries of about 3% are probably not easily avoided if mechanical abrading is resorted to. It must be noted, however, that even this reduction in germinative capacity causes significant yearly loss. If the reduction in germinative capacity is greater, which seems to be possible, it is advisable to test the mechanism of the machine and its method of abrading. As the clearance of the machines can affect the extent of injuries, all machines should be tested. If possible, a continual operation control should be arranged. It could, at the same time, to supply material for improving the abrading method and equipment.

The PDF includes a summary in English.

  • Yli-Vakkuri, E-mail: py@mm.unknown (email)
article id 7452, category Article
Olli Vaartaja. (1955). Factors causing mortality of tree seeds and succulent seedlings. Silva Fennica vol. 62 no. 3 article id 7452.
Keywords: seedling damage; seeds; drought; heat tolerance; soil types; germling
Abstract | View details | Full text in PDF | Author Info

Germlings and small tree seedlings are exposed to extreme conditions in the forest floor. In this study the influence of climatic factors to seeds and seedlings were studied experimentally, and an attempt was made to estimate the importance of various factors in several sowing experiments in Finland.  

Seeds of Scots pine (Pinus sylvestris L.) were subjected to temperature variations which simulated those of exposed forest sites. The seeds lost some of their germinative capacity during the five-day treatments. Succulent seedlings died when subjected to immersion for 15 minutes at temperatures from 51.5 to 55 ºC. After a hardening pretreatments the seedlings tolerated 2-3 ºC higher temperatures. In artificial humus soil exposed to strong insolation for 15 minutes, temperatures in the range of 54-65 ºC proved to be critical for the seedlings. In natural conditions, also little lower temperatures may prove fatal. Exposure of succulent seedlings of Scots pine and Norway spruce (Picea abies (L.) Karst.) to insolation showed that most damage occurred on humus, quartz sand, and humus-sand mixture, due to rapid evaporation. Seeds of Scots pine, Norway spruce, Betula pendula and Betula pubescens tolerated poorly drought if germination had progressed to a 5–10 mm long radicle. Succulent seedlings tolerated 53-77 days long drought better in humus than in fine silty sand. Seedlings of Pinus sylvestris, Picea abies, Alnus incana and A. glutinosa tolerated cold variably. The developmental stage of the seedling affected cold resistance. Pine seeds sown in furrows germinated well after rain and the survival was high. Frost heaving, snail and insects caused some damages. Germination was lowest at the shallowest furrows. Sowing on natural surfaces gave poor results. Largest damages were caused by birds and ants. 

 The PDF includes a summary in Finnish.  

  • Vaartaja, E-mail: ov@mm.unknown (email)
article id 7421, category Article
Olli Heikinheimo. (1954). Taimitarhan maantieteellinen sijainti, siemenen alkuperä ja istutuskaudet. Silva Fennica vol. 61 no. 9 article id 7421.
English title: Geographical location of a tree nursery, seed origin and planting seasons.
Original keywords: taimitarha; taimituotanto; istutus; alkuperä; istutusaika; siemenet; siemenen alkuperä; istutuskausi
English keywords: planting; seedling production; seeds; provenience; tree nursery; planting time
Abstract | View details | Full text in PDF | Author Info

Planning of large central tree nurseries, which has become topical in Finland, means that the seedlings will be used in a wide geographical area. The nursery must decide which proveniences of seeds of the different tree species it will use. This concerns also the customer that buys the seedlings. The planting and lifting of the seedlings in the nursery have to be timed so that the seedlings are in a right state of growth at the time of planting.

The growth of the seedlings can, under certain conditions, be promoted by using a slightly southerly seed provenience, and large-sized seeds. There are, however, limitations to how much the seeds can be transferred northwards. If the nursery lies much south of the planting site, the seedlings have started height growth at the time of planting. This applies especially larch (Larix sp.), Scots pine (Pinus sylvestris L.) and birch (Betula sp.), but affects less Norway spruce (Picea abies (L.) Karst.). The problem can be handled by using a cool storage space for the seedlings waiting for a delivery in the nursery.

According to an international study, seedlings grown from seeds collected in countries south from Finland usually die already during the first two years in the nursery. Within Finland the seeds can be transferred at least by two latitudes. Spruce seems to tolerate longer transfer. Seed orchards should be planted south of the seed’s origin to ensure better yield and better quality seeds.

The Silva Fennica issue 61 was published in honour of professor Eino Saari‘s 60th birthday.
The PDF includes a summary in German.

  • Heikinheimo, E-mail: oh@mm.unknown (email)
article id 7367, category Article
Esko Kangas. (1942). Karistuslämmön vaikutuksesta männyn siemenen karisemiseen ja itämiseen. Silva Fennica vol. 50 no. 14 article id 7367.
English title: Effect of seed extracting temperature on extraction and germination of Scots pine seeds.
Original keywords: mänty; siementuotanto; itäminen; siemenet; karistus; karistuslämpötila
English keywords: Pinus sylvestris; germination; Scots pine; temperature; seeds; seed production; seed extraction
Abstract | View details | Full text in PDF | Author Info

Temperatures needed in extracting Scots pine (Pinus sylvestris L.) seeds is relatively high, however, there is little information on its effect on germination of the seeds. This survey aimed at studying how different temperatures affect both extraction result and germination of Scots pine seeds. Comparisons between different temperatures (20, 30, 40, 50, 60 and 70 ºC) were made from cones collected from same sample trees, three trees in total.

Temperatures 20 and 30 ºC resulted in incomplete opening of the cones, and gave thus smaller amount of seeds. Complete extraction requires at the least the temperature of 40 ºC. The result is slightly better in 50 ºC, but germination of the seeds is little lower. Temperatures 60 and 70 ºC improve the results, but in the cost of germination. The main reason for lower germination percentage was that the higher temperatures release more empty and defective seeds from the cones. Results of different sample trees were different due to, for instance, quality and size of cones. Higher temperatures accelerated the extraction. According to the study, perfect extraction in 40 ºC requires longer extraction time than when the temperature of 50 ºC is used. In practice, 50 ºC temperature or even little higher temperatures can be used when the extraction time is shorter. Decessive factors in choosing the temperature would be the humidity of cones and length of extraction time.

The PDF includes a summary in German.

  • Kangas, E-mail: ek@mm.unknown (email)

Category: Research article

article id 9996, category Research article
Mulualem Tigabu, Mostafa Farhadi, Lars-Göran Stener, Per C. Odén. (2018). Visible + Near Infrared Spectroscopy as taxonomic tool for identifying birch species. Silva Fennica vol. 52 no. 4 article id 9996.
Keywords: Betula; silver birch; downy birch; seeds; NIRS; OPLS; multivariate modelling
Highlights: Multivariate modelling of visible + near infrared (NIR) reflectance spectra of single seeds distinguished Betula pubescens and B. pendula with 100% and 99% accuracy, respectively; The results demonstrate the feasibility of NIR spectroscopy as taxonomic tool for classification of species that have morphological resemblance.
Abstract | Full text in HTML | Full text in PDF | Author Info

The genus Betula L. is composed of several species, which are difficult to distinguish in the field on the basis of morphological traits. The aim of this study was to evaluate the taxonomic importance of using visible + near infrared (Vis + NIR) spectra of single seeds for differentiating Betula pendula Roth and Betula pubescens Ehrh. Seeds from several families (controlled crossings of known parent trees) of each species were used and Vis + NIR reflectance spectra were obtained from single seeds. Multivariate discriminant models were developed by Orthogonal Projections to Latent Structures – Discriminant Analysis (OPLS-DA). The OPLS-DA model fitted on Vis + NIR spectra recognized B. pubescens with 100% classification accuracy while the prediction accuracy of class membership for B. pendula was 99%. However, the discriminant models fitted on NIR spectra alone resulted in 100% classification accuracies for both species. Absorption bands accounted for distinguishing between birch species were attributed to differences in color and chemical composition, presumably polysaccharides, proteins and fatty acids, of the seeds. In conclusion, the results demonstrate the feasibility of NIR spectroscopy as taxonomic tool for classification of species that have morphological resemblance.

  • Tigabu, Swedish University of Agricultural Sciences, Southern Swedish Forest Research Centre, Box 49, SE-230 52 Alnarp, Sweden E-mail: (email)
  • Farhadi, Swedish University of Agricultural Sciences, Southern Swedish Forest Research Centre, Box 49, SE-230 52 Alnarp, Sweden E-mail:
  • Stener, The Forestry Research Institute of Sweden, Ekebo 2250, SE-268 90 Svalöv, Sweden E-mail:
  • Odén, Swedish University of Agricultural Sciences, Southern Swedish Forest Research Centre, Box 49, SE-230 52 Alnarp, Sweden E-mail:
article id 481, category Research article
K. S. Wang. (2003). Relationship between empty seed and genetic factors in European beech (Fagus sylvatica L.). Silva Fennica vol. 37 no. 4 article id 481.
Keywords: Fagus sylvatica L.; allozyme; empty seeds; selfing; outcrossing rate; correlation
Abstract | View details | Full text in PDF | Author Info
The relationship between percentage of empty seed (Pes) and genetic factors was explored in an isolated stand of European beech (Fagus sylvatica L.). Nine allozyme loci (GOT-B, IDH-A, LAP-A, MDH-B, MDH-C, MNR-A, 6-PGDH-A, PGI-B and PGM-A) were used to estimate genetic factors. Pes ranged from 4.8% to 40.9% for seed samples of 91 trees within the stand and showed an approximate normal distribution. The average Pes was 21.4% and the repeatability of Pes was 43.4%. The multilocus estimate for outcrossing rate (tm) based on seed samples of 30 trees within the stand was 1.015 (SE = 0.011) and the mean single locus estimate was slightly higher at 1.061 (SE = 0.026). No evidence of biparental inbreeding was found. Weak positive correlation between Pes and maximum selfing rate as well as and significant negative correlation between Pes and multilocus outcrossing rate indicated that self-fertilization may be explained as one of the important causes of empty seeds in beech.
  • Wang, Program in Genetics and Genomic Biology, Research Institute, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario, M5G 1X8, Canada E-mail: (email)
article id 661, category Research article
Eira-Maija Savonen, Anna Saarsalmi. (1999). Effects of clone and fertilization on the seed and foliar chemical composition of Scots pine (Pinus sylvestris) grafts. Silva Fennica vol. 33 no. 2 article id 661.
Keywords: needles; Scots pine; nutrient concentration; seeds; seed orchards
Abstract | View details | Full text in PDF | Author Info
Effects of clone and fertilization on the seed and foliar nutrient concentrations of Scots pine grafts were investigated in a seed orchard in southern Finland. The seed and foliar samples for chemical analyses were collected during winters 1985–86 and 1988–89 from 39 grafts per clone fertilized in spring 1986. There were 6 clones and 13 treatments for each clone with three replications. The treatments consisted of N, P, K in various combinations, micronutrients, wood ash and grass control. Macro- (N, P, K, Ca, Mg) and micronutrients (Cu, Zn, B) were analysed. There were statistically significant differences between the clones in seed nutrient concentrations. The variation of the K, Mg, Ca, Zn and Cu concentrations between the two study years was considerably larger in the seeds than in the needles. The concentrations of these elements in the seeds were low in the year of an abundant seed crop in spite of fertilization. This had, however, no negative effects on germination of seeds. The proportions of crude fat and crude protein were high in both years (34% and 35% in 1985 ; 33% and 38% in 1988). Fertilization had only minor or no effect at all on the seed chemical composition in the orchard with a satisfactory nutrient status of the soil. Also on the foliar nutrient concentrations the effect of the clone was stronger than that of fertilization. Grafts with large needles produced heavy seeds, which had more storage proteins than the lighter seeds.
  • Savonen, The Finnish Forest Research Institute, Parkano Research Station, Kaironiementie 54, FIN-39700 Parkano, Finland E-mail: (email)
  • Saarsalmi, The Finnish Forest Research Institute, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail:

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