Scots Pine Seedlings Research Articles

Indiferentní reakce sazenic borovice lesní a buku lesního ošetřených hydroabsorbenty

Super-absorbents are expected to amend soils as they are capable of retaining water, which turns dry loose powdery substances (also capsule) into hydrogel. These were applied to prevent an artificial regeneration failure due to drought events. Four commercially-available products were mixed with soil from planting holes (the capsule was put to the soil) in order to support bare-root Scots pine and European beech seedlings after a spring planting on eleven clear-cut sites in 2020–2021. The plantations were designed as rows with 4 × 150 plants treated with four hydrogels plus 150 plants without hydrogel as a control. The performance evaluation of new plantations was based on attributes such as mortality/survival and relative height and root-collar diameter increments. The plants, which lost their initial size, due to pine weevil damage, dry tops and damage by game, were excluded from the evaluation. Besides the plant response to the applied super-absorbents, the planting operations were evaluated from economic point of view. The 2020 plantations showed higher mortality than 2021 ones; both years showed an excessive loss. The hydrogels did not help the plants to survive better compared to control and growth data also showed ambiguous results. Therefore, from commercial perspective, the application of all tested super-absorbents just increased the renewal costs.

Responses of needle terpene concentrations and characteristics of resin canals to different warming treatments in Scots pine and Norway spruce seedlings grown in a field experiment

We studied responses of needle terpene concentrations and resin canal characteristics to warming in Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) seedlings grown in a controlled field set-up in eastern Finland. Warming was simulated during the growing seasons using infrared heaters that increased air temperature in study 1 (2016–2019) by 1°C and in study 2 (2019–2020) by 2°C and 4°C, compared to ambient conditions. Terpenes were sampled in study 1 from non-matured current year and matured previous year needles in June 2019, and study 2 from mature current-year needles in August 2020. In study 1, we also studied resin canal anatomy. We found that 1°C elevation of temperature caused two-fold increase in concentrations of total terpenes, oxygenated monoterpenes and sesquiterpenes of non-matured current year needles of Norway spruce. Further, it caused 1.3-1.8-fold increases in sesquiterpene concentrations both in unmatured and matured needles of Scots pine. It also decreased resin canal diameter of mature needles in Norway spruce. In study 2, the stronger warming treatments did not affect terpene concentrations of matured current-year needles in either species. Based on our findings, even minor elevation of temperature may affect terpene concentrations of non-mature needles in boreal conifers.

Biogenic secondary organic aerosol participates in plant interactions and herbivory defense.

Biogenic secondary organic aerosols (SOAs) can be formed from the oxidation of plant volatiles in the atmosphere. Herbivore-induced plant volatiles (HIPVs) can elicit plant defenses, but whether such ecological functions persist after they form SOAs was previously unknown. Here we show that Scots pine seedlings damaged by large pine weevils feeding on their roots release HIPVs that trigger defenses in neighboring conspecific plants. The biological activity persisted after HIPVs had been oxidized to form SOAs, which was indicated by receivers displaying enhanced photosynthesis, primed volatile defenses, and reduced weevil damage. The elemental composition and quantity of SOAs likely determines their biological functions. This work demonstrates that plant-derived SOAs can mediate interactions between plants, highlighting their ecological significance in ecosystems.

Ensuring Tree Protection, Growth and Sustainability by Microbial Isolates

Antimicrobial properties of the new strains of micro-organisms isolated from natural sources of various ecological niches in the Moscow region and the Republic of Tatarstan were studied. Antifungal activity of isolates was detected in a test culture of toxin-producing microscopic fungi that can cause animal and plant diseases: Aspergillus flavus, Candida albicans, Fusarium oxysporum and Penicillium spp. Of the 46 studied micro-organisms of genera Bacillus, Lactobacillus, Lactococcus and Streptomyces isolates, there are four strains (Bacillus subtilis, Lactobacillus plantarum, Propionibacterium freudenreichii and Streptomyces spp.) that showed an ability to produce biologically active metabolites with a pronounced antimicrobial potential against phytopathogenic fungi metabolites. Based on the selected four strains, a Bacterial product LRV composition has been created. Scots pine, pedunculate oak and small-leaved linden seedlings with single and double foliar treatment and Bacterial product LRV at a concentration of 10 mL/L led to an increase in the growth of the aboveground part by 31.8, 51.9 and 25.4%, respectively, and the underground part by 25.0, 37.2 and 25.7%, respectively, compared to the control. The weight of seedlings at the end of the study exceeded the control variant by an average of 26.0, 44.0 and 78.0%, respectively. Plant protection Bacterial product LRV use did not have a significant effect on the group of molds that caused the powdery mildew and Schütte disease damage to trees. The Biological product LRV provided plant protection from fungal diseases caused by Lophodermium pinastri Chev. and Microsphaera alphitoides.

Recovery of Scots Pine Seedlings from Long-Term Zinc Toxicity.

We studied the recovery of the growth and physiological parameters of Scots pine seedlings after long-term zinc toxicity. The removal of excess zinc from the nutrient solution resulted in the rapid recovery of primary root growth but did not promote the initiation and growth of lateral roots. The recovery of root growth was accompanied by the rapid uptake of manganese, magnesium, and copper. Despite the maximum rate of manganese uptake by the roots, the manganese content in the needles of the recovering plants did not reach control values during the 28 days of the experiment, unlike magnesium, iron, and copper. In general, the recovery of ion homeostasis eliminated all of the negative effects on the photosynthetic pigment content in the needles. However, these changes, along with recovery of the water content in the needles, were not accompanied by an increase in the weight gain of the recovering seedlings compared with that of the Zn-stressed seedlings. The increased accumulation of phenolic compounds in the needles persisted for a long period after excess zinc was removed from the nutrient solution. The decreased lignin content in the roots and needles is a characteristic feature of Zn-stressed plants. Moreover, the removal of excess zinc from the nutrient solution did not lead to an increase in the lignin content in the organs.

Open geospatial data can predict the early field performance of Scots pine, Norway spruce and silver birch seedlings in Nordic boreal forests

ABSTRACT Accurate knowledge of site conditions and their effects on regeneration establishment is important for selecting the most appropriate tree species and regeneration methods for a given regeneration site. This study examined the response of the first-year field performance of Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) Karst.) and silver birch (Betula pendula Roth.) seedlings in boreal forests to variables available in open forest and natural resources datasets. Survival, height increment and damage of planted tree seedlings and the success of direct seeding of pine were analysed on a total of 284 plots (1000 m2) in 18 regeneration experiments established in 2020–2022 in southern and central Finland. The height increment of silver birch was higher than that of conifers, while the lowest mortality rate was found for spruce. In the generalised linear mixed models, topographic wetness index, soil texture, site type and growing stock at clearcut explained the species-specific survival and height increment of planted seedlings and the success of pine seeding. Low-cost, open geospatial data effectively provide useful details on the site conditions suitable for diversifying tree species composition in boreal forests instead of monocultures.

Comparison of deacclimation and reacclimation of silver birch, Norway spruce and Scots pine seedlings during winter warm and cold spells in Nordic boreal conditions

Climate change means that in many areas in boreal region, the duration and thickness of the winter snow cover is decreasing. Young seedlings are exposed to fluctuating winter temperatures in the absence of protecting snow cover. Responses to winter warm and cold spells were studied with Scots pine (Pinus sylvestris L.), silver birch (Betula pendula Roth.), and Norway spruce (Picea abies (L.) Karts.) container seedlings in Finland. The frost hardiness of whole seedlings and buds was determined for seedlings sampled directly from outdoor overwintering conditions, after 7-day deacclimation (+5 °C; +7 °C in late March) and deacclimation combined with 7-day reacclimation ( − 7 °C) treatments between January and late March. The frost hardiness of buds and whole seedlings in Scots pine was between − 40 and − 30 °C from January to early March. Norway spruces tolerated at least − 50 °C in midwinter, but their frost hardiness in outdoor conditions decreased more rapidly in March than that of Scots pines. Silver birch tolerated − 30 °C in February. During simulated warm spells, the Scots pine and silver birch deacclimated without an ability to reacclimate during simulated cold spells. The buds and whole seedlings of Norway spruces also deacclimated, but they had some ability to reacclimate in February and early March, but not in late March. In Nordic boreal conditions, one-year-old Scots pines and silver birches respond strongly to fluctuating winter temperatures during snowless winters, whereas Norway spruces can tolerate typical winter temperatures in midwinter, but their frost hardiness may reduce during warm spells in March.

Effects of small-scale outplanting fertilization on conifer seedling growth and fungal community establishment

Forestry in Sweden largely relies on planting genetically improved seedlings after clear-cutting, and high survival and early growth of planted seedlings is vital for stand establishment, economic viability, and carbon sequestration. Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) are the two most important tree species in Swedish forest stands and both are associated with a variety of ectomycorrhizal fungi. While seedlings are generally not fertilized at outplanting, previous results have shown that fertilization with arginine phosphate can increase root growth and seedling survival. However, it is not clear how this affects fungal community composition on the roots of growing seedlings. In a planting experiment sampled after one and two growing seasons, we found that planting position had the largest effects both on seedling performance and on fungal community composition and provide insight into the early stages of fungal community succession on planted Norway spruce and Scots pine seedlings. Fungal taxa present on seedlings before planting persisted on seedling roots, while some degree of novel colonization by site indigenous taxa was observed. Fertilization modified the relative abundance of some fungal taxa but did not lead to significant changes in overall community composition. In terms of seedling performance, ammonium nitrate led to increased mortality while arginine phosphate improved root growth.

Effects of Planting Position, Seedling Size, and Organic Nitrogen Fertilization on the Establishment of Scots Pine (Pinus sylvestris L.) and Norway Spruce (Picea abies (L.) Karst) Seedlings

The forest regeneration phase in Sweden commonly involves mechanical soil preparation followed by the planting of Scots pine (Pinus sylvestris L.) or Norway spruce (Picea abies (L.) Karst) seedlings. The prepared soil offers planting positions with different properties, including reduced damage by pine weevils (Hylobius abietis L.). Nitrogen fertilization can be applied at the time of planting to aid establishment of the seedlings. In this study, we compared the effects of different planting positions, organic nitrogen fertilization, and different seedling sizes on the early survival and growth of Scots pine and Norway spruce seedlings. The main planting positions were capped mound, hinge, and mineral soil. Seedlings planted close to organic material were categorized as being in “low-quality positions”, since proximity to organic material increases pine weevil attraction. Higher mortality rates related to pine weevil damage were recorded for the seedlings planted in the low-quality positions, regardless of seedling size or N fertilization. Pine weevil attack rates increased with increasing seedling size. Growth was, in general, lowest in the mineral soil positions. The effect of organic N fertilization on growth was positive for the spruce regardless of the planting position or seedling size, while it depended on the planting position and seedling size for the pine, indicating that the effects of organic N fertilization depend on the seedling species, seedling size, and planting position.

Influence of Sayanogorsk Aluminum Plant emissions on morphological characteristics and phytopathology of Scots pine (<i>Pinus sylvestris</i> L., 1753)

This article presents data on the variability of morphological features and cytogenetic indicators in Scots Pine (Pinus sylvestris) growing in areas affected by the industrial activity of the Sayanogorsk Aluminum Plant (SAP). We demonstrated that in polluted plots located at a distance of 1 and 5 km from the plant, the reproductive organ indicators of pine significantly decreased, germination energy and viability decreased, and needle necrosis frequency increased compared with the control. A significant increase in the frequency of class III needle necrosis in experimental plots by 7.2–8.6 times compared with the control, as well as a decrease in germination energy and seed germination in experimental plots by 1.1 and 1.3–1.5 times indicates the strong negative impact of SAP emissions on pine. Mitotic index and frequency of chromosomal aberrations in the apical meristem cells of Scots Pine seedlings were determined by cytogenetic analysis. A considerable reduction in mitotic activity by 1.35 to 0.8 times was observed in the meristem cells of Scots Pine growing in experimental plots, compared with the control plot. A tendency toward an increase in the frequency of abnormal mitoses of Scots Pine in the experimental areas was observed. Thus, the data obtained made it possible to assess the condition of Scots Pine in areas exposed to the influence of SAP.

The effect of ectomycorrhizal fungal exposure on nursery-raised Pinus sylvestris seedlings: plant transpiration under short-term drought, root morphology and plant biomass.

Drought is a major environmental stressor that limits seedling growth. Several studies have found that some ectomycorrhizal fungi may increase the drought tolerance of nursery-raised seedlings. However, the precise role that different ectomycorrhizal fungi species play in drought tolerance remains unclear. We evaluated the transpiration rate of Pinus sylvestris seedlings under drought stress in greenhouse conditions by exposing seedlings to 10 ectomycorrhizal fungi species, with different functional traits (exploration type and hydrophobicity), and to 3 natural soil inoculums. We measured the transpiration and water potential of the seedlings during a 10-day drought period and a 14-day recovery period. We then analyzed their root morphology, stem, needle, root biomass and needle chlorophyll fluorescence. We showed that exposing seedlings to ectomycorrhizal fungi or soil inoculum had a positive effect on their transpiration rate during the driest period and through the recovery phase, leading to 2- to 3-fold higher transpiration rates compared with the nonexposed control seedlings. Seedlings exposed to medium-distance ectomycorrhizal fungi performed better than other exploration types under drought conditions, but ectomycorrhizal fungi hydrophobicity did not seem to affect the seedlings response to drought. No significant differences were observed in biomass accumulation and root morphology between the seedlings exposed to different ectomycorrhizal fungi species and the control. Our results highlight the positive and species-specific effect of ectomycorrhizal fungi exposure on drought tolerance in nursery-raised Scots pine seedlings. The studied ectomycorrhizal fungi functional traits may not be sufficient to predict the seedling response to drought stress, thus physiological studies across multiple species are needed to draw the correct conclusion. Our findings have potential practical implications for enhancing seedling drought tolerance in nursery plant production.

Nitrogen uptake, retranslocation and potential N2-fixation in Scots pine and Norway spruce seedlings

Nitrogen uptake, retranslocation and potential N2-fixation in Scots pine and Norway spruce seedlings

Comparing the effects of ground cultivation and protection against browsing upon the natural regeneration of Scots pine and birch in a Caledonian pinewood

Abstract The Caledonian pinewoods of northern Scotland represent the remnants of once extensive forests found at the western edge of the natural range of Scots pine (Pinus sylvestris L.). The surviving pinewoods are of international significance and are of high conservation and cultural value. However, for many decades, there has been concern about their long-term future because of a lack of regenerating seedlings and young trees. This problem is thought to be driven by high deer populations resulting in intensive browsing and severe damage to young trees, as well as a lack of favourable micro-sites for seedling germination. An experiment was established on the Mar Lodge estate in 2007–08 adjacent to native pinewood stands to test the effects of protection and site cultivation upon seedling numbers and growth. The experiment was located within a regeneration zone where intensive deer control had reduced numbers to <5 animals km−2. Ten years after initiation, occurrence and numbers of both Scots pine and birch seedlings were substantially increased in cultivated treatments compared with uncultivated controls. There were no effects of protection upon seedling numbers. Protection improved height growth of Scots pine, but not of birch. Cultivation had no effect upon the growth of pine seedlings but did influence the height of birch seedlings due to the rapid growth of some pre-existing seedlings in the uncultivated control. Vegetation cover had increased from ~60%to at least 80% cover 6 years after cultivation. The results suggest that site cultivation may be desirable to boost seedling germination within a Caledonian pinewood, but sustained measures to control browsing pressure are a prerequisite for satisfactory establishment of these seedlings.

Natural regeneration and early development of Scots pine seedlings after gap cutting in northern Finland

ABSTRACT In the northern boreal region, tree growth, timber yields and economic returns are low, meaning low regeneration costs are the basis of profitable forestry. If natural regeneration is successful, it may be favoured over expensive planting or seeding. We studied the regeneration success and early growth of Scots pine in gaps in terms of seedling density and height 10 years after gap cuttings in central Finnish Lapland. Three gap sizes (diameters of 20, 40, and 80 m) were studied on patch scarified xeric and sub-xeric sites in six random blocks and a total of 18 replicates of each. The number of pine seedlings was high across the gap sizes. The proportion of empty regeneration plots (size 5 m2) was ∼ 2%. Site preparation substantially increased the number of seedlings. The growth of seedlings was faster in larger gaps, but a high proportion of exposed mineral soil decreased it. The results suggest that all studied gap sizes regenerated naturally well, and that soil scarification exposing 10–20% of the surface area or even less can be enough to achieve regeneration goals. Gaps of a diameter of 40 m or more are required to achieve an optimal balance between seedling density and growth.

Annual dynamics of ammonium and nitrate nitrogen content by using capsulated carbamide in cassettes of one-year-old seedlings of Scots Pine (Pinus sylvestris)

Over the past decades of forestry development in Russia, the main trends have been identified, according to which P. sylvestris planting material can be effectively grown in a container method with a closed root system, considering the forest-seed area. The purpose of the study was to study the annual dynamics of ammonium and nitrate nitrogen in a soil with P. sylvestris with a closed root system using encapsulated urea with hydroquinone and mulch. The objectives of the study were based on the study of the effect of mineral fertilizers on the annual dynamics of ammonium and nitrate nitrogen and their effect on the growth of seedlings. The object of the study was the dynamics of the content of these nitrogen compounds in the soil. The study was carried out by methods of agrochemical, biometric and statistical analysis. Thus, the use of extended-form carbamide makes it possible to cover the need of plants for nitrogen nutrition throughout the growing season, having a significant impact on their growth in stem height. The use of encapsulated carbamide with hydroquinone, 0.5 cm pine mulch, potassium monophosphate and phosphorous flour allows the production of the best P. sylvestris seedlings with a maximum height of 188.82±15.41 mm per year due to constant saturation of the soil with available nitrogen, on which a change in the growth rate of seedlings is almost directly dependent (R = 0.99821-0.99988; Multiple R = 0.99643-0.99977; Adjusted R = 0.98928-0.99930; p < 0.01525-0.05978). At the same time, ammonium nitrogen has the greatest effect on it (p < 0.01633-0.05436).

Assessment of the growth of forest seedlings in new substrates from wood waste and sewage sludge

The morphological parameters of Scots pine (Pinus sylvestris L.) seedlings grown in experimental substrates made from sewage sludge and pine shavings (substrate 1), and pine bark (substrate 2) were studied. The production time of the substrate varied: substrate 1 – 2 months, substrate 2 – 1.5 years. Seedlings of 2-year-old pine were selected for research. To analyze the parameters of seedlings, average values and square deviations were calculated, reliability was determined by Fisher and Student tests. To analyze the length of the root system, one-way analysis of variance was used in MS Excel. For roots of the 2nd order and total root length, the observed values of Fisher’s criterion are: 15.42 and 11.27, which exceeds the critical value of 3.18 and indicates a significant difference between seedlings grown in the manufactured substrates. The diameter of the root collar of seedlings grown in peat exceeded that of seedlings grown on substrate 2 by 13%, and in substrate 2 by 4.4%. Maximum root length for seedlings from substrate 1. Substrates from wood waste and sewage sludge can replace fossil peat without losing the quality of growing seedlings and contribute to the emergence of improved quality characteristics of seedlings.

The influence of agricultural cultivation technology on biometric characteristics Scots pine seedlings

The influence of agricultural cultivation technology on biometric characteristics Scots pine seedlings

Разработка агротехнологии получения посадочного материала, устойчивого к фитофагам и фитопатогенам

Many seedlings die early during reforestation. Traditional bareroot technologies often fail in Western Siberia. As a result, containerized technologies have become relevant as they provide higher survival rate in the harsh climatic conditions.
 The study traced the development of Scots pine (Pinus sylvestris L.) seedlings grown in a container nursery in the Kemerovo Region. The milled high-moor peat had a degree of decomposition of ≤ 15%. The seeds were treated with fungicides before planting. The seedlings underwent a double treatment against phytophages and phytopathogens during growth.
 The article introduces a new agricultural technology for ball-rooted planting stock resistant to phytophages and phytopathogens. The study revealed the developmental stages of pine seedlings and the effect of pesticides on pathogen count. After phytosanitary monitoring and preventive treatments, the seedlings were tested for the effectiveness of pesticides, fungicides, and insecticides as part of pre-planting seed treatment. Such biochemical preparations as Fitoverm (0.4%), Decis Pro, Previkur Energy, and Fitosporin increased the survival rate of the test seedlings. The biological effectiveness of the experimental treatment was 49–53 and 44–50%.
 The technology was able to improve the survival rate of pine seedlings in forest container nurseries in the harsh climate of West Siberia.

The effects of arginine phosphate (ArGrow® Granulat) on growth of Scots pine and Norway spruce seedlings planted in varying soil layer structures simulating site preparation

The effects of arginine phosphate (ArGrow® Granulat) on growth of Scots pine and Norway spruce seedlings planted in varying soil layer structures simulating site preparation

A Reliable and Simple Method for the Production of Viable Pycnidiospores of the Pine Pathogen Diplodia sapinea and a Spore-Based Infection Assay on Scots Pine.

Diplodia sapinea is a globally distributed opportunistic fungal pathogen of conifers that causes severe production losses in forestry. The fungus frequently colonizes pine trees as an endophyte without causing visible symptoms but can become pathogenic when the host plant is weakened by stress, such as drought or heat. Forest damage might therefore further increase due to the effects of climate change. The future development of control strategies depends on a better understanding of the fungus' biology, which requires experimental methods for its investigation in the laboratory. An efficient, standardized protocol for the production and storage of highly viable pycnidiospores was developed, and a spore-based infection method was devised. We compared infection rates of dormant and actively growing, wounded, or nonwounded Scots pine seedlings inoculated with in vitro-produced spores and mycelium from agar-plugs. Spores were a much more efficient inoculum for causing disease symptoms on wounded plants than the conventional agar plug. The application of spores on nonwounded plants lead to high rates of asymptomatic infection, suggesting endophytic fungal development. These methods enable standardized spore infection and virulence assays and promote D. sapinea as a model organism for studying the switch from endophytic to pathogenic life styles of forest pathogens.