Articles containing the keyword 'germinatio'
Category : Article
A multi-factor experimental approach and proportional odds model were used to study interactions between five environmental factors significant to Norway spruce (Picea abies (L.) H. Karst.) seed germination: prechilling (at +4.5°C), suboptimal temperatures (+12 and +16°C), osmotically induced water stress (0.3 Mpa and 0 Mpa), prolonged white light, and short-period of far-red light. Temperature and osmotic stress interacted with one another in the germination of seeds; the effect off osmotic stress being stronger at +16°C than at +12°C. In natural conditions, this interaction may prevent germination early in the summer when soil dries and temperature increases. Prolonged white light prevented germination at low temperature and low osmotic potential. Inhibitory effect was less at higher temperatures and higher osmotic potential, as well as after prechilling. Short-period far-red light did not prevent germination of unchilled seeds in darkness. Prechilling tended to make seeds sensitive to short pulses of far-red light, an effect which depended on temperature: at +12°C the effect on germination was promotive, but at +16°C, inhibitory and partly reversible by white light. It seems that Norway spruce seeds may have adapted to germinate in canopy shade light rich in far-red. The seeds may also have evolved mechanisms to inhibit germination in prolonged light.
-
Leinonen,
E-mail:
kl@mm.unknown
- Rita, E-mail: hr@mm.unknown
The aim of the study was to obtain information needed in preparing more precise fertilization recommendations for seed orchards. The fertilization requirement was estimated on basis of soil and needle analyses, and by investigating the effects of different fertilization treatments on male and female flowering, size of seed crop and seed quality.
The study was carried out in two Scots pine (Pinus sylvestris L.) seed orchards in Southern Finland, one established on forest soil in 1971 and 1972, and the other on a peat field in 1974. 10 clones and 39 grafts from each clone were selected randomly from both orchards in autumn 1985. The treatments consisted of N, P and K in various combinations, micronutrients, wood ash and grass control. The orchards were fertilized in spring 1986.
There were statistically significant differences between the clones in both orchards as regards amount of flowers, size of the seed crop and seed quality. The annual variation in flowering and the size of the seed crop was also large. In general, the seeds from cones collected in October matured well and their germination percentage was high. The effects of fertilization on flowering, the size of seed crop and seed quality were small. It would appear that the size of the crop can be affected to a much greater extent by favouring clones with a high seed-producing capacity than through fertilization. Fertilization is unnecessary if the nutrient status of the soil is satisfactory.
-
Saarsalmi,
E-mail:
as@mm.unknown
- Lipas, E-mail: el@mm.unknown
- Mikola, E-mail: jm@mm.unknown
- Nikkanen, E-mail: tn@mm.unknown
- Savonen, E-mail: es@mm.unknown
The potential alleopathic inhibitive effects of aqueous extracts of 13 peatland plant species on germination, radicle and seedling growth of Scots pine (Pinus sylvestris L.), silver and downy birch (Betula pendula Roth., B. pubescens Ehrh.) were studied. Freshly cut plant parts were finely ground, mixed with distilled water and agitated. The proportions of fresh plant mass in the mass-based extracts varied within the range of 1, 5, 10 and 20% (w/w). The seeds were germinated in petri dishes moistened with the plant extracts. In a separate experiment growth of birch seedlings irrigated with the extracts was studied.
Ledum palustre, Vaccinium uliginosum and Empetrum nigrum extracts, and in certain experiments extracts of other species, inhibited the germination of Scots pine and birch seeds. Results from the different experiments were not, however, fully consistent. None of the low (1% w/w) extract concentrations had any effect on germination. Strong extract concentrations (20% w/w) inhibited germination of pine seedlings significantly. The extracts affected only slightly the growth of potted birch seedlings.
The PDF includes an abstract in Finnish.
-
Hytönen,
E-mail:
jh@mm.unknown
Effect of dolomite lime and wood ash (0, 0.5, 1, 2, 4, 8 and 16 kg m-3) on the chemical composition of low humified Sphagnum peat was studied. Germination of Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) H. Karst.) and silver birch (Betula pendula Roth) and the subsequent growth of these seedlings were investigated in a greenhouse experiment. Nutrient concentrations in shoots and roots of pine seedlings were also analysed. The pH of peat increased asymptotically from 3.8 to about 7.0 with increasing lime regimen and to about 8.0 with increasing ash regimen. Wood ash linearly increased electrical conductivity and P, K, and Ca concentrations of peat. Rate of germination, within 7 days, of pine and spruce was best at low pH (<5) while birch seeds had a slightly higher pH optimum (4–6). Germination capacity, within 21 days, was not affected by pH or application regimen of either lime or ash. Pine and spruce seedlings grew best with lime and ash doses of 0.5–2.0 kg m-3, the pH of peat being 4–5. Lime and ash treatments did not affect the growth of birch seedlings, but wood ash increased nutrient concentration of pine seedlings.
The PDF includes an abstract in Finnish.
-
Rikala,
E-mail:
rr@mm.unknown
- Jozefek, E-mail: hj@mm.unknown
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
The occurrence of Caleopsis bifida on clear-cut and burned forest soil and its disappearance in 4–6 years after disturbance is attributed to its germination ecology. Initially the seeds are dormant 96–100% and remain dormant in nylon gaze bags in different types of forest humus layers at least 10 years. Dormancy is released in laboratory (1) by treatment of 100 ppm aqueous solution of GA3, (2) by heating the dormant seeds to 40–55°C for 1–5 h, and (3) by 1% KNO3 solution. It is concluded that conditions in clear-cut and burned areas favour germination of seeds in regard to temperature and content of nitrates in contrast to humus of closed vegetation where the seeds remain dormant.
The PDF includes an abstract in Finnish.
-
Hintikka,
E-mail:
vh@mm.unknown
In the model the regeneration process is derived into three subprocesses: birth, growth and mortality of seedlings. The main emphasis is on the birth process where the following phases are simulated: seed crop, quality of seeds, maturity of seeds, predation of seeds and germination. The parameters are based on data published in Finland. Part of the parameters are obtained directly from the investigations and part is proposed by the author. The model can be calibrated by changing parameter values. The simulation is made with the help of random numbers which have the same means as the estimates and the same distributions as the residuals of the equations used in simulation. The time step of the model is one year. The number of emerged seedlings in one year is obtained by multiplying the seed crop with the probabilities that the seed passes different phases of the birth process. Because of stochasticity the regeneration period is simulated several times. From the results it is possible to evaluate the risk and succeeding probability of the regeneration. The main drawbacks of the simulation method are the lack of empirical parameters and the difficulty of testing. The model could be further developed by including spatiality into the model.
The PDF includes an abstract in Finnish.
-
Pukkala,
E-mail:
tp@mm.unknown
Six seed collections were made in September–December 1984 in a natural Scots pine (Pinus sylvestris L.) stand in Southern Finland. The seeds were germinated immediately after the cone collection and three photoperiods (0.8 and 24 hours) were used in germination tests.
The seeds collected in September and October possessed relative dormancy, i.e. they did not germinate in darkness and at 10°C. Later in November and December the seeds were capable to germinate in darkness and at low temperature also. The gradual change in germination capacity is attributed to chilling temperatures in natural environments or in cone storage.
The PDF includes a summary in English.
-
Nygren,
E-mail:
mn@mm.unknown
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
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
Needle fascicles of Scots pine (Pinus sylvestris L.) were rooted in a standard Jacobsen’s germination apparatus. The apparatus was found to be suitable for rooting at least on laboratory scale. The best rooting substrate was living Sphangnum, which remained sufficiently moist in the germination containers throughout the experiments. In a comparison of various growth substrate treatments, the best result was obtained with a combination of IAA (100 mg/l) and thiamine (5 mg/l). The rooting percentage using these growth substances with Sphagnum as the rooting medium was in the first experiment 30 and in the second 48.
The PDF includes a summary in Finnish.
-
Yli-Vakkuri,
E-mail:
py@mm.unknown
- Pelkonen, E-mail: pp@mm.unknown
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
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
- Pahkala, E-mail: kp@mm.unknown
The aim of the study was to assess, through field experiments, the possibilities of using peat briquettes in the seeding of Scots pine (Pinus sylvestris L.) in Southern Finland. The briquettes were dug into the soil in the middle of patches of mineral soil. The seeds were covered by a 2-5 mm layer of mineral soil. The seedings were inventoried in the three following autumns.
According to the results, the briquettes were clearly inferior to the control, which was ordinary drill seeding. This was mainly due to the fact that no rain was received after the seeding, and that the third summer from seeding was extremely dry. Abundant germination was observed during the second summer after seeding in both briquette seeding and the control. During more rainy summers the result might have been better.
The PDF includes a summary in English.
-
Lehtiniemi,
E-mail:
tl@mm.unknown
The study was an attempt to assess, from a theoretical viewpoint and with the techniques of measurement in mind, the usability respiration and cumulative respiration in the observation of the progress of seed germination in Norway spruce (Picea abies (L.) H. Karst.), as well as the influence of air temperature substrate moisture and the stage of physiological development of seeds on respiration. Furthermore, the reserve nutrient consumption and the possible uptake of mineral nutrients were kept under observation during the 9–11 days after seeding.
The results showed that the stage of physiological development of the seeds can be rather well described by the means of cumulative CO2 release. There was a strong interaction in the CO2 release between the moisture of the substrate and the air temperature. It seems to be to great extent due to differences in the rate of development in the early phases of germination. The CO2 release from seeds showed a close correlation with percentage germinated seeds.
The PDF includes a summary in English.
-
Hari,
E-mail:
ph@mm.unknown
- Lehtiniemi, E-mail: tl@mm.unknown
Experiments were carried out to find out the effect of fertilizer application on germination, seedling emmergnece and initial development in conifer plantations established on peat by sowing, with a special reference to Scots pine (Pinus sylvestris L.). The experiments were carried out in 1968–70 in laboratory, in greenhouse and in the field.
In the greenhouse experiments with Y fertilizer for peat soils (14% N, 18% P2O5, 10% K2O) it was shown that germination and seedling emergence decreased markedly with increased fertilizer application. Mortality among seedlings that had emerged was the higher the larger quantities of fertilizer had been applied. The effect of fertilization was the greater, the drier the substrate. Fine ground rock phosphate (33% P2O5) promoted seedling emergence on a dry substrate but not on a wet one.
The field experiments carried out in Central Finland included dry and wet sites. Y fertilizer, Oulu Saltpeter (25% N), fine-ground rock phosphate and potassium salt (50% K2O) were used. According to the results, easily soluble fertilizers decreased seedling emergence. On wet sites the effect of Y fertilizer was weaker than on drier sites. Fine-ground rock phosphate slightly increased the number of seedlings emerging. Height growth was increased during the first three growing seasons only by those fertilizers containing phosphorus.
The PDF includes a summary in English.
-
Mannerkoski,
E-mail:
hm@mm.unknown
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
- Räsänen, E-mail: pr@mm.unknown
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
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
Category : Article
This paper aims at studying regeneration of Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.) by sowing and natural regeneration of birch (Betula sp.) in Western Finland.
Germination of spruce and pine seeds may be prevented by dryness and temperatures below the optimum for germination. In natural conditions, when temperature and moisture is insufficient for germination, the type of seedbed generally has en effect on germination result. Trenching of the seeding spots showed that root competition during the early stage of regeneration was not of decissive importance. It seemed to, however, improve the preservation of the seedlings later. It is common that it can take long before the seeds germinate, and during that time the number of viable seeds decrease strongly.
Also, the seedling stock quickly began to decrease in number after germination, especially during the first growing season and the following winter. The decrease was larger in intact vegetation than on mineral soil or in the humus layer. The emerging seedlings were destroyed by drought very easily, but their tolerance to drought improved later on.
The PDF includes a summary in English.
-
Yli-Vakkuri,
E-mail:
py@mm.unknown
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
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
The aim of the study was to investigate effect of growth conditions on germination and growth of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) seedlings in greenhouse conditions. Germination of seeds becomes markedly slower as the soil temperature decreases. It seems that low temperatures affect more Norway spruce than Scots pine. When temperature rises, the fresh weight of the seedlings increases more in pine seedlings than in spruce seedlings. Accordingly, lower temperatures affect less the weight growth of spruce seedling than that of pine seedlings.
An experiment testing how root competition affect germination showed that adjacent seedlings decrease germination of seeds more than shading with branches. The effect was strongest on pine and spruce seedlings when the shading tree species was fast growing birch (Betula sp.). On the other hand, shading affected most height growth of birch seedlings. Growing space can vary in relatively large range without it affecting greatly tree growth.
The PDF includes a summary in German.
-
Aaltonen,
E-mail:
va@mm.unknown
Germination tests in varying photoperiod- and temperature-regimes showed that for early autumn collections, germination of Scots pine (Pinus sylvestris L.) seeds is delayed, especially at low incubation temperature (+10°C) and in darkness. The presence of light during germination (8- or 24-hour photoperiod) or high incubation temperature (+20°C) enhanced germination. As autumn proceeded, a greater proportion of seed were able of germinate in darkness and also in low temperature regime. This result was consistent in both populations studied – in seeds from natural stand (Hyytiälä, Southern Finland) and in seeds from the Hyytiälä clone archive trees, growing in the same site.
An attempt was made to relate the development of germinability during autumn to previously accumulated chilling unit (optimum temperature +3.5°C) sum. Germination percent variation in subsequent cone-collection could not, however, be explained with accumulated chilling.
The PDF includes a summary in Finnish.
-
Nygren,
E-mail:
mn@mm.unknown
Category : Research article
Colchicine is widely used as a mutagen to induce production of diploid gametes in plants. However, whether colchicine affects induced pollen viability remains unclear. To clarify whether colchicine affected the viability of induced pollen, we induced production of diploid pollen by colchicine, followed by pollen germination in vitro and crossing induced pollen with normal gametes to produce triploid in Populus tomentosa Carrière. The results showed that the predominant meiotic stages and the number of colchicine injections had significant effects on the occurrence rates of induced 2n pollen. When the colchicine injection was given at diakinesis, a significant decrease in the pollen production per bud was observed (p < 0.001). The morphology of the colchicine-induced 2n pollen was similar to that of the natural 2n pollen in its ectexine structure. The pollen germination experiments revealed that there was also no significant difference in germination rates between the induced diploid pollen and natural 2n pollen grains, and 68 triploids were created by crossing colchicine-induced pollen. Our findings revealed that colchicine injection could induce P. tomentosa to produce 2n pollen and will not lead to dysfunction of induced diploid pollen.
- Liu, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing 100083, China; College of Bioscience and Biotechnology, Beijing Forestry University, Beijing 100083, China E-mail: 342767649@qq.com
- Zhang, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing 100083, China; College of Bioscience and Biotechnology, Beijing Forestry University, Beijing 100083, China E-mail: 409192881@qq.com
- Zhou, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing 100083, China; College of Bioscience and Biotechnology, Beijing Forestry University, Beijing 100083, China E-mail: 876034493@qq.com
- Wu, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing 100083, China; College of Bioscience and Biotechnology, Beijing Forestry University, Beijing 100083, China E-mail: 1269485709@qq.com
-
Zhang,
National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing 100083, China; College of Bioscience and Biotechnology, Beijing Forestry University, Beijing 100083, China
E-mail:
zhangpd@bjfu.edu.cn
In the present study, the impact of geographical isolation and habitat conditions on genetic diversity and sexual reproduction was tested in four relict populations of dwarf birch Betula nana L. in Poland and Belarus. Amplified fragment length polymorphism (AFLP) method revealed that the endangered central European stands were not genetically extirpated compared with the widespread localities from Finland and Russia, which can result from infrequent outcrossing events in long-living clonal populations. However, genetic clustering methods indicated significant differentiation of the Polish populations because of their small sizes and long-term geographical isolation. Considerable numbers of empty seeds were observed in both relict and central locations, although fully developed seeds germinated better in widespread populations. Analysis of groundwater chemical parameters indicated that two relict populations were significantly different from the remaining samples with respect to pH, electrical conductivity and concentrations of phosphorus ions, which can also influence the efficiency of sexual reproduction. In the light of results obtained it seems that endangered B. nana localities are relatively stable.
-
Jadwiszczak,
Institute of Biology, University of Białystok, Ciołkowskiego 1J, 15-245 Białystok, Poland
http://orcid.org/0000-0002-9345-8891
E-mail:
jadwiszczak2010@gmail.com
- Kłosowski, Department of Environment Protection and Modelling, The Jan Kochanowski University, Świętokrzyska 15, 25-406 Kielce, Poland E-mail: stanislaw.klosowski@ujk.kielce.pl
- Zalewska, Faculty of Pharmacy, Medical University of Białystok, Mickiewicza 2a, 15-222 Białystok, Poland E-mail: iwonazalewska1988@gmail.com
- Banaszek, Institute of Biology, University of Białystok, Ciołkowskiego 1J, 15-245 Białystok, Poland E-mail: banaszek@uwb.edu.pl
- Chrzanowska, Institute of Biology, University of Białystok, Ciołkowskiego 1J, 15-245 Białystok, Poland E-mail: maga.chrzanowska@gmail.com
- Koivuranta, Finnish Forest Research Institute, Haapastensyrjä, Finland E-mail: lk@nn.fi
- Latva-Karjanmaa, Finnish Forest Research Institute, Haapastensyrjä, Finland E-mail: tlk@nn.fi
-
Pulkkinen,
Finnish Forest Research Institute, Haapastensyrjä, Finland
E-mail:
pertti.pulkkinen@metla.fi
-
O'Reilly,
UCD School of Biology and Environmental Science, UCD College of Life Sciences, University College Dublin, Belfield, Dublin 4, Ireland
E-mail:
conor.oreilly@ucd.ie
- De Atrip, UCD School of Biology and Environmental Science, UCD College of Life Sciences, University College Dublin, Belfield, Dublin 4, Ireland E-mail: nda@nn.ie
