Pine Seeds Research Articles

Stratification, Scarification and Application of Phytohormones Promote Dormancy Breaking and Germination of Pelleted Scots Pine (Pinus sylvestris L.) Seeds

Seed quality is an important issue in forestry as it is an essential parameter in the production of high quality planting material. Many factors may hinder the harvesting of high quality seeds, including an insufficient number of sunny days, external conditions in temperate climate zones, and fungal pathogens affecting development of seedlings. We undertook to develop a procedure maximizing seed protection and promoting the optimum physiological development of seedlings by examination of the impact of seed pelleting (a general seed protection method) on germination rates and seedling development of Scots pine (Pinus sylvestris L.). Germination of pelleted seeds was examined in relation to substrate (water vs. soil) and LED light spectrum (white vs. red-blue). Several dormancy breaking treatments were applied: stratification/scarification, and growth regulator treatments including gibberellic acid (GA3), indole-3-acetic acid (IAA) and 1-naphthaleneacetic acid (NAA), to stimulate seed germination. Experiments included independent tests for each treatment (stratification/scarification and plant growth regulators), and combinations of both stratification/scarification and phytohormone treatments. The impacts of these treatments and various controlled germination conditions on the fluorescence of chlorophyll were analyzed using the maximum efficiency of photosystem II photochemistry parameter (Fv/Fm). In addition, chlorophyll a and b content in Scots pine seedlings germinated from pelleted seeds, were quantified using high-performance liquid chromatography (HPLC). The combined stratification/scarification and growth regulator treatment was the most effective germination promoting method for pelleted Scots pine seeds. Scots pine seeds are highly likely to be photoblastic. The best germination rate, while maintaining optimal physiological parameters, was achieved in acidic soil (pH 5.0) with white LED light.

Effect of Extracts from Dominant Forest Floor Species of Clear-Cuts on the Regeneration and Initial Growth of Pinus sylvestris L. with Respect to Climate Change.

Climate change influences the ecological environment and affects the recruitment of plants, in addition to population dynamics, including Scots pine regeneration processes. Therefore, the impact of cover-dominant species extracts on the germination of pine seeds and morpho-physiological traits of seedling under different environmental conditions was evaluated. Increasing temperature reinforces the plant-donor allelochemical effect, reduces Scots pine seed germination, and inhibits seedling morpho-physiological parameters. Conditions unfavourable for the seed germination rate were observed in response to the effect of aqueous extracts of 2-year-old Vaccinium vitis-ideae and 1-year-old Calluna vulgaris under changing environmental conditions. The lowest radicle length and hypocotyl growth were observed in response to the effect of 1-year-old C. vulgaris and 2-year-old Rumex acetosella under increasing temperature (+4 °C) conditions. The chlorophyll a + b concentration in control seedlings strongly decreased from 0.76 to 0.66 mg g−1 (due to current environmental and changing environmental conditions). These factors may reduce the resistance of Scots pine to the effects of dominant species and affect the migration of Scots pine habitats to more favourable environmental conditions.

Recent findings suggest adding red fox to climate-threatened whitebark pine trophic system

Mountain ecosystems are sensitive to climate change, and climate-driven declines in primary producers can impact food webs. Whitebark pine (Pinus albicaulis Engelm.) seed, a valuable food resource for montane wildlife species, is threatened by climate change. Whitebark pine exhibit masting, and during a snowtracking study of Rocky Mountain red foxes (Vulpes vulpes macroura Baird, 1852) in the Greater Yellowstone Ecosystem that happened to coincide with masting, we unexpectedly observed red foxes consuming whitebark pine seeds from red squirrel (Tamiasciurus hudsonicus Erxleben, 1777) middens. Seed production then decreased the following year. To investigate whether whitebark pine seed availability affected winter foraging and habitat use by red foxes, we assessed interannual variance in our dietary and habitat use data. We found both seed consumption and use of habitats where seeds were available also decreased during the non-mast winter. Given the limitations of our small-scale, opportunistic analysis, we suggest whitebark pine seeds may be an important food resource for red foxes, and that their relationship warrants further research and consideration in conservation efforts for both species.

The impact of temperature patterns during storage of Scots pine and Norway spruce seeds on their germination and fungal infection rates

Relevance of the study. One of the ways to maintain the genetic diversity of forest-forming species is to preserve highquality seed material ex situ. However, the relationship between the diversity of pathogenic mycobiota and the duration and methods of forest tree seed storage remains underexplored. The results of research into this problem can be used in forest seed production and forest phytopathology.Materials and methods. For our study we used seeds ofРinus sylvestris L. and Picea abies (L.) Karst. of the orthodox type, harvested in the period of 1996–2011 and stored under different temperatures: +20°С, +4°С, –18°С, and in liquid nitrogen vapor (–182°С) since 2011. Prior to their storage, seed samples were dried to a moisture content of 4.2–4.4% and hermetically packed. Seed germination was tested before and after three, five and eight years of storage, following GOST 13056.6-97 standards. The level of seed infection and the composition of pathogenic fungi were assessed.Results. After eight years of storage at +20°С, pine and spruce seed germination capacity decreased by 13–60%, depending on the year of harvesting. Seed storage at –18°С and –182°С allowed us to prevent seed infection and preserve seed viability. In most cases, the germination energy and germination capacity were negatively correlated with the level of seed infection. The diversity of pathogenic (mold) fungi on the surface of seeds was represented by ten genera; the most common were saprotrophs: Aspergillus P. Micheli, Penicillium Link, Rhizopus Ehrenb., Scopulariopsis Bainier.Conclusion. At the present stage of research, the success of seed storage at low and ultralow temperatures was demonstrated. We recommend cryopreservation for the long-term storage of improved and valuable seeds.

Factors Affecting Seed Germination and Establishment of an Efficient Germination Method in Sugar Pine (Pinus lambertiana Dougl.)

Mature sugar pine (Pinus lambertiana Dougl.) trees produce large amounts of viable seeds but have seed dormancy. In this study, we used three sugar pine genotypes, 8877, 9306, and 9375, to test seed germination response. Seed germination from local sources varied greatly, and germination percentages were poor. There was a large variation in seed size and seed weight among the genotypes. Seeds of 9375 and 9306 were significantly larger and heavier (30.7 and 28.8 g/100 seeds, respectively) than 8877 (23.6 g/100 seeds). Three types of seeds—intact seeds, hulled seeds, and naked embryos—were examined for germination. Intact seeds failed to germinate due to the physical restraint and water impermeability of the seed. Chemical scarification with 5 m hydrochloric acid and 5 m sodium hydroxide did not soften the hard seedcoat and also failed to induce any germination of intact seeds. Hulled seeds resulted in an extremely low germination percentage (≤5%) with abnormal seedling development even though the endosperm was water permeable. Germination of the hulled seeds was not increased by adding 1 mg·L−1 gibberellic acid to the culture medium. Artificial opening of the hulled seeds created by longitudinal or horizontal cuts on the endosperm after removal of the seedcoat to avoid physical restraint and allow air exchange also failed to improve germination, indicating that inhibitors related to germination were present in the endosperm. However, naked embryos of all three genotypes germinated rapidly and uniformly with 70% to 95% germination percentage regardless of cold stratification treatment. Our data indicate that sugar pine seeds from the current source did not have physiological dormancy of embryos themselves, but dormancy was imposed by the seedcoat and endosperm. Using the naked embryos as donor explants, we have successfully established an efficient in vitro culture system. The protocol described here can be applied for the tissue culture and genetic transformation of sugar pine.

Detection of Scots Pine Single Seed in Optoelectronic System of Mobile Grader: Mathematical Modeling

The development of mobile optoelectronic graders for separating viable seeds by spectrometric properties with high detection accuracy represents a very relevant direction of development for seed handling operations. Here, the main parameters of the radiation source and receiver for detecting a single seed in the diagnostic system of a mobile grader were modeled based on the principles of technical optics using Scots pine (Pinus sylvestris L.) seeds as a case study. Among the pine seeds in the seed batch, there are fossilized and empty seeds that are exactly the same in geometric and gravitational parameters as live seeds. For their separation from the seed batch, data from spectrometric studies in the near-infrared (980 nm) region can be used. To substantiate the parameters of the light source, a geometric optical model of optical beam formation was considered, while the energy model of optical beam formation was considered to substantiate the parameters of the light detector. The results of this study show that the signal value depended on the orientation of a single seed relative to the recording window. The beam angle from the radiation source should be within 45 degrees. The difference between the optical streams should be 50 microns, which made it possible to clearly detect the signal at a standard noise level of 15 microns and signal-to-noise detection accuracy ratio of 56.3 dB. This study expands theoretical knowledge in the field of the spectrometric properties of a single seed, considering the cases of its orientation relative to the optical beam, which affected the effective area of detection of the seed. The obtained data on the location of the main elements of the diagnostic system will speed up the design of mobile optoelectronic graders, and the development of a contemporary protocol for improving Scots pine seed quality.

Grading of Scots Pine Seeds by the Seed Coat Color: How to Optimize the Engineering Parameters of the Mobile Optoelectronic Device

Research Highlights: There is a problem of forest seeds quality assessment and grading afield in minimal costs. The grading quality of each seed coat color class is determined by the degree of its separation with a mobile optoelectronic grader. Background and Objectives: Traditionally, pine seeds are graded in size, but this can lead to a loss of genetic diversity. Seed coat color is individual for each forest seed and is caused to a low error in identifying the genetic features of seedling obtained from it. The principle on which the mobile optoelectronic grader operates is based on the optical signal detection reflected from the single seed. The grader can operate in scientific (spectral band analysis) mode and production (spectral feature grading) mode. When operating in production mode, it is important to determine the optimal engineering parameters of the grader that provide the maximum value of the separation degree of seed-color classes. For this purpose, a run of experiments was conducted on the forest seeds separation using a mobile optoelectronic grader and regression models of the output from factors were obtained. Materials and Methods: Scots pine (Pinus sylvestris L.) seed samples were obtained from cones of the 2019 harvest collected in a natural stand. The study is based on the Design of Experiments theory (DOE) using the Microsoft Excel platform. In each of three replications of each run from the experiment matrix, a mixture of 100 seeds of light, dark and light-dark fraction (n = 300) was used. Results: Interpretation of the obtained regression model of seed separation in the visible wavelength range (650–715 nm) shows that the maximum influence on the output—separation degree—is exerted by the angle of incidence of the detecting optical beam. Next in terms of the influence power on the output are paired interactions: combinations of the wavelength with the angle of incidence and the wavelength with the grader’s seed pipe height. The minimum effect on the output is the wavelength of the detecting optical beam. Conclusions: The use of a mobile optoelectronic grader will eliminate the cost of transporting seeds to and from forest seed centers. To achieve a value of 0.97–1.0 separation degree of Scots pine seeds colored fractions, it is necessary to provide the following optimal engineering parameters of the mobile optoelectronic grader: the wavelength of optical radiation is 700 nm, the angle of incidence of the detecting optical beam is 45° and the grader’s seed pipe height is 0.2 m.

Comparative study of the fullness of dwarf Siberian pine seeds <em>Pinus pumila</em> (Pall.) Regel from places of natural growth and collected from plants introduced in northwestern Russia by microfocus X-ray radiography to predict their sowing qualities

As a result of analysis of the quality of Pinus pumila seeds by the method of microfocus X-ray radiography in combination with the automatic analysis of digital X-ray images, it was found that the best characteristics of individual structures and organs of seeds were demonstrated in samples collected from trees growing at site 71 of BIN RAS; the worst — from seeds taken from South Sakhalin. The seeding qualities of Pinus pumila seed samples were determined by standard methods. Based on analysis of the characteristics of digital X-ray images of Pinus pumila seeds, it was found that a seed sample from site 71 BIN RAS was characterized by the high level of embryo area 4.19±0.49 mm2, maximum embryo to thalus ratio 60.95±7.45 %, high level of endosperm area 23.93±1.24 mm2, and maximum ratio square of embryo area 9.45 ±1.17 %. The same sample was characterized by a maximum weight of 1000 seeds and a maximum absolute and soil germination ratio, compared to other samples. The obtained data showed that Pinus pumila seeds collected from plants introduced in northwestern Russia by most parameters are not inferior or are even superior to seeds from the natural range.

Weather as main driver for masting and stem growth variation in stone pine supports compatible timber and nut co-production

Trade-offs between life-history traits are common in plants, and those involving growth and reproduction may be evident during mast years. The nutlike seeds of the stone pine (Pinus pinea L.) stand out among the most appreciated Mediterranean forest products, but its lengthy reproductive cycle makes the identification of masting mechanisms challenging. In the Spanish Northern Plateau, stone pine woodlands are managed as multifunctional forests. Here, we investigated whether timber and nut production are compatible goals in the region. Temporal ring-width and cone yield patterns were characterised in five monospecific stands since 1960. At tree level, we found an equivalent allocation of resources to reproductive and non-reproductive (aboveground) biomass for an average year, but harvest index exceeded 80% during mast years. These large yields, however, did not impose a penalty on aboveground biomass increment. Regionally, we reported a slightly larger magnitude of high-frequency synchronous growth (â = 0.50) compared with that of reproduction (â = 0.42), which is important to contextualise the ecological and economical relevance of masting for the species. By investigating growth-yield interannual dynamics, we found that both traits were strongly and positively correlated, although with a 3-year lag. Therefore, years favouring a high growth coincided with large conelet emergences leading to abundant seed rains to occur three years later, which pointed to key environmental drivers common to both traits. Actually, radial growth and reproduction partly responded to the same climate factors, with climate three years before seed rain being related to masting in a similar way as it was related to ring-width of this same year. Our results provide evidence for the proposed link between masting and growth, and suggest that resources are not diverted from growth during cone filling in stone pine. We conclude that timber production and nut production are perfectly compatible in this species.

Adaptation of foreign technologies of intensive cultivation of scots pine planting material in Kazakhstan

The purpose of the research was the adaptation of foreign technologies for intensive and accelerated cultivation of Scots pine planting material in Kazakhstan. Objects of research were annual seedlings of scots pine in forest nurseries of Pavlodar, Akmola, and North Kazakhstan regions. The experiments were established in 4 directions: application of dry growth regulators to soil, pre-sowing seed treatment with growth regulators, soaking seeds in stimulants and fungicide, pre-sowing watering of the soil with growth regulators. It was established that seed quality decreased significantly compared to the last year, only seeds from Pavlodar region had high indicators. Seeds from the nursery ‘Ertic Ormany’ had the highest average indicators of soil germination (58.7…67.8%). In ‘Bukhpa’, the highest germination was observed in seeds soaked with Zircon + Trichocin (3 + 2 hours). Baikal growth regulator and AridGrow slightly increased germination in the nursery of Arykbalyk branch of ‘Kokshetau’. In the forest nursery ‘Ertis Ormany’, the highest annual seedlings were obtained in variants with presowing treatment of scots pine seeds with stimulants and watering the soil with growth substances. The average height of experimental seedlings was 4.32 and 4.64 cm, respectively. The combined use of Zircon and Trichocin increased seedling growth in ‘Bukpa’ nursery to 1.42 cm, which was the highest value. It was revealed that the technologies used in neighboring countries for intensive cultivation of scots pine seedlings showed a positive effect only when using Citovit. According to other experiments, it was determined that seedlings of scots pine grown from seeds with pre-sowing treatment in Gumat+7 for 12 hours had the best growth indicators in height. Increased soil fertility through applying nitrogen, phosphorus fertilizers, soil activator AridGrow and KZ Cultury significantly accelerated growth of scots pine seedlings.

Conspecific presence, but not pilferage, influences pinyon jays' (Gymnorhinus cyanocephalus) caching behavior.

Caching species store food when plentiful to ensure availability when resources are scarce. These stores may be at risk of pilferage by others present at the time of caching. Cachers may reduce the risk of loss by using information from the social environment to engage in behaviors to secure the resource-cache protection strategies. Here, we examined whether pinyon jays, a highly social corvid, use information from the social environment to modify their caching behavior. Pinyon jays were provided with pine seeds to cache in two visually distinct trays. The cacher could be observed by a non-pilfering conspecific, a pilfering conspecific, or an inanimate heterospecific located in an adjoining cage compartment, or the cacher could be alone. After caching, the pilfered tray was placed in the adjoining compartment where caches were either pilfered (pilfering conspecific and inanimate heterospecific conditions) or remained intact (non-pilfering conspecific and alone conditions). The safe tray was placed in a visible, but inaccessible, location. Overall, pinyon jays reduced the number of pine seeds cached in the pilfered tray when observed, compared with caching alone. However, their caching behavior did not differ between the pilfering conspecific and the non-pilfering conspecific conditions. These results suggest that either pinyon jays were unable to discriminate between the pilfering and non-pilfering conspecifics, or they generalized their experience of risk from the pilfering conspecific to the non-pilfering conspecific. Thus, we report evidence that pinyon jays use cache protection strategies to secure their resources when observed, but respond similarly when observed by pilfering and non-pilfering conspecifics.

Selection of Scots pine seedling growth stimulants in extreme conditions of the Northern Kazakhstan steppe zone

The aim of this research is to determine optimal methods of using stimulants in a pre-sowing treatment of common pine seeds to increase their germination and obtain high-quality planting material. A study has been performed in forest nurseries of the State Forest Natural Reserve (SFNR) “Ertis Ormany” (Pavlodar region) and the Arykbalyk Branch of the State National Natural Park (SNNP) “Kokshetau” (Akmola region). The research is done with one-and two-year-old seedlings of ordinary pine sowing of 2017. A presowing seed preparation is carried out according to six options by using various types of stimulants. A method of mathematical processing of the thus obtained measurements of the seedlings with an insufficient number of measured plants is proposed by using a bootstrap analysis with and without quantile information. It allows one to estimate the influence of stimulants on the average growth of one-and two-year-old seedlings at a reliable level. As a result of these studies, it has been revealed that the pre-sowing treatment of pine seeds with ordinary stimulants increases the average height of annual seedlings. However, the results obtained in this experiment depend on the region of nursery location, but the use of soil irrigation with an “EridGrow” activator has increased the average height in both nurseries: by 13.9% in the “Kokshetau” SNNP for one-year-old seedlings, by 37.2% for two-year-old seedlings compared with the average height of the control seedlings. For pine seedlings in the “Ertis Ormany” SFNR nursery the influence of the stimulants is insignificant, but the positive effect on the average growth with the “EridGrow” soil irrigation is a 7.3% increase in the first year and a 24.7% one in the second year.

Forest cover dynamics of the Bazoy Siberian pine (Pinus sibirica Du Tour) forest from 1915 to 2015

Abstract The article considers the long-term (100 years) dynamics of the forest cover of the southernmost unit of Siberian pine forests on the West Siberian plain. A key feature of forest management is that Siberian pine seeds are a valuable food product and, when cutting forests, this tree species, as a rule, is preserved. The basis of the experimental data was the material of the national forest inventories of 1915, 1974 and 2015 for a total area of 1,420.41 ha. During the period from 1915 to 2015, the forested area changed slightly (96.2 and 94.0%), while the share of Siberian pine stands increased significantly from 48.4 to 58.7%. Grassy Siberian pine forests (32.1%) of optimal age (120–140 years), which are characterised by the best seed productivity and the largest share of Siberian pine in the community (77%), predominate. Basically, human economic activity results in an increase in the area of Siberian pine stands, when deciduous stands with Siberian pine undergrowth are used for fuel and as building material. A decrease in the area of Siberian pine forests occurs mainly under the impact of fires. In the conflagrations of 1915–1920, 7 to 38% of silver birch forests have no Siberian pine undergrowth and are considered long-term secondary communities. In the remaining area, the proportion of Siberian pine undergrowth is 20–30% with a density of 800–1200 seedlings ha−1, which is sufficient for the natural formation of Siberian pine forests.

Результаты изучения географических посадок сосны и лиственницы в Серебряноборском опытном лесничестве

The results of the cultivation of Scots pine (Pinus sylvestris L.) in the provenance trial in the Serebryanoborsky experimental forest district of the Institute of Forestry of the Russian Academy of Sciences are summarized. The silvicultural effect was assessed by a comprehensive indicator of the feasibility of introducing specific pine conventions. It was established that the use of pine seeds of exclusively local provenances cannot be considered justified. In the vast area of pine there are very remote populations of a local nature, the seed of which, when moved, can be successfully used to create highly productive artificial stands. The 68 year old geographical plantations of larch growth and production rates of 18 climotypes of 14 larch species were compared. These species are Polish larch (Larix polonica Racib.), European larch (Larix decidua Mill. f. Sudetica), Larix sukaczewii Dylis, Siberian larch (Larix sibirika Ledeb.), Larix cajanderi Mayr., Larix gmelinii Rupr., Larix Czekanovskii Szaf, Larix amurensis Kolesn., Olgan larch (Larix olgensis Henry), Japanese larch (Larix kaempferi (Lamb.) Carrière), Larix kurilensis Maur., Larix principis Rupprechtii Maur., Larix potaninii Bat, American larch (Larix laricina (Duroi) K. Koch). Polish larch, Japanese larch, European larch and Olgan larch have the best growth rate results. Climotypes from Siberia and American larch showed worst results. Polish larch (812 m3/ha) and Japanese (804 m3/ha) larch from the Southern Sakhalin have the highest stem volume. The final estimations showed that the climotypes of Polish larch, European larch from Sudetes and Japanese larch from the Southern Sakhalin are suitable for introduction in the Moscow Region. The climotypes from the Far East, namely Larix amurensis Kolesn., Olgan larch and Larix kurilensis Maur., had positive silvicultural effect. The inland climotypes from Asia together with American larch showed negative results.

Prescribed Burning as A Management Tool to Destroy Dry Seeds of Invasive Conifers in Heathland in Denmark

Non-indigenous conifers are considered invasive to the coastal dune heathland in Denmark, and massive clearing is carried out in an attempt to recreate and keep the original heathland. Burning is a common method for managing, but its feasibility to control the seed bank of conifers has not been investigated. This project shows that the burning of logged conifer trees will often eliminate seeds of lodgepole pine, mugo pine and Sitka spruce, even when the seeds were placed into a depth of five centimeters in the soil. The effect on seeds depends on the fuel load and the fire conditions (e.g., dryness, wind, and temperature). If the seeds were exposed to a high temperature, the seeds were not able to germinate afterward. The temperature was about 80 °C for all species. If the sum of temperatures based on temperature records every 30 s exceeded between 12,000 and 14,000 °C no seeds were able to germinate. The relationship between the mean temperature of the burns and the germination rate at seeds placed in various soil depths was modelled. Findings should be interpreted cautiously as each depth-species combinations were not replicated in space or time due to practical constraints.

The practice of using a sieveless separator for pre-sowing treatment of common pine seeds (Pinus sylvestris)

The paper presents the results of studies on the effect of calibrating Scots pine (Pinus sylvestris) seeds on the morpho-biological characteristics of seedlings. The studies were carried out in 2017-2019. Scots pine seeds were used as the object of research. In the course of the research, laboratory and field methods were used. The seeds were calibrated using a sieveless separator, which makes it possible to obtain several tens of seed fractions with a size gap of 0.02 mm. It was found that plants of large seeds were characterized by a higher starting growth. Throughout the growing season, the advantage of these fractions persisted. Due to the higher growth rate of small fraction plants, the difference between plants decreased by the end of the growing season. By the end of the first year of vegetation, there was some advantage of large seedlings, the height of which varied from 6.95 cm (second fraction) to 7.18 cm (fourth fraction). The seedlings of these fractions were characterized by the highest uniformity (17.0%). At the end of the second growing season, the most intensive growth was noted in seedlings of large seeds, due to which a large planting material is formed, characterized by high uniformity.

The features designed of mechatronic system of adaptive hopper’s feeder: case study for Scots pine seeds morphometry

This article will be of interest to engineers involved in designing devices for improving the quality of forest seeds. From the point of view of automated processing, in order to obtain a quality seedling, the seed of the Scots pine must be conditioned, that is, properly graded, and have sufficient ability to germinate in the field, that is, properly sown. It is based on studies of the movement of a single pine seed in the mechanical system of an optoelectronic separator. The experiment was established by measuring the geometric dimensions of samples (n = 500) from a representative sample of a seedlot. The Pinus sylvestris L. seeds were collected in the Pavlovsky district of the Voronezh region in autumn 2019. Seed samples were measured using a microscope in three mutually perpendicular directions. Seed samples asymmetric shape and an adaptive hopper’s feeder were modeled using SolidWorks software. Our results point to an important feature in the design of loading bins-the need to approximate the complex shape of a single seed of Scots pine with an asymmetric ellipsoid. The need for discrete seed feeding with a frequency no faster than 10−3-10−2 s is established to improve both the separation process.

Sensory evaluation and acceptance of food made of edible insects

This paper discusses the sensory analysis of food enriched with selected edible insect species which are labelled as a novel food – house cricket (Acheta domesticus) and mealworm (Tenebrio molitor). Energy bars of two different compositions with the addition of cricket flour and puff pastry bars sprinkled with the whole roasted mealworm larvae were evaluated by consumer tests performed via a questionnaire survey. Respondents represented both men and women in equal numbers and included consumers with the experience of the sensory analysis and edible insects to ensure accurate results. Sensory analyses revealed that respondents associated their tastes with already known flavors (salty, sweet, bitter, fish, French fries, chicken, and mushrooms). The most common answer from respondents was a salty taste, followed by a sweet taste. There were also unusual comparisons such as pine seeds. Consumers’ positive attitude to these energy bars has been registered which shows that the Czech consumer accepts edible insects in a suitable form as a novel food and possible part of the food basket.

Growth and Development of Seedlings of Scots Pine and European Spruce Container Seedlings Using Various Materials to Neutralise the Substrate

The article analyses the features of growth and development of seedlings of Scots pine and European spruce on substrates in which various materials were used to neutralise them, affecting the reaction of the environment. According to the research results, the highest germination of seeds of both woody species was established on substrates with a ratio of dolomite flour of 30% and chalk of 70%, while in the case of using pure chalk, seed germination was significantly lower. Scots pine seeds germination in the substrate ranged from 77.6% to 90.1%, and European spruce seeds – from 66.4% to 94.3%. During the cultivation of seedlings of Scots pine and European spruce container seedlings, differences in the content of mobile forms of phosphorus are noted in all variants of the experiment. However, no definite pattern was found depending on the share of participation of various types of lime material. In the substrate of seedlings of Scots pine at the end of the growing season, the content of nitrate nitrogen naturally increases from 1069.1 to 1323.6 mg/100 g of absolutely dry substrate with a decrease in the proportion of dolomite and an increase in the proportion of chalk in the lime neutralising material. Another pattern is manifested when growing seedlings of European spruce container seedlings: the lowest content of nitrate nitrogen (412.1 mg/100 g of absolutely dry substrate) is established in the case of mixing dolomite flour and chalk in equal proportions (option 3). Differences in the content of mobile forms of iron were revealed in all experimental versions of the substrate of both woody species. For the cultivation of Scots pine, its amount ranges from 16.67 to 28.81 mg/100 g of absolutely dry substrate, and European spruce – from 18.40 to 20.99 mg/100 g of absolutely dry substrate. In general, low content of mobile iron was observed in the substrate of growing pine and spruce seedlings in containers. In all experimental variants, the height of seedlings of Scots pine container seedlings exceeds the required average height of the aboveground part in accordance with national standard by 1.3-2.0 times, and for seedlings of European spruce the excess was 1.2-1.5 times. In seedlings of Scots pine and European spruce, according to the variants of the experiment, the average height of the aboveground part rises with an increase in the concentration of dolomite in the mixture of neutralising material from 50% and higher

ИССЛЕДОВАНИЕ ТЕХНОЛОГИЧЕСКИХ ПАРАМЕТРОВ РЕШЕТНОЙ УСТАНОВКИ

Annual harvesting of a large number of forest seeds allows for reforestation on the territory of the Russian Federation. Moreover, more than 70% falls on the seeds of coniferous trees. In order to increase their sowing quality and reduce losses, the seeds are dehumidified, cleaned, sorted by density and size, stratification, as well as other technological operations. The use of refined seeds during reforestation allows increasing the productivity of sowing units, improving the quality of seed placement, reducing the volume of seed bins, which leads to a decrease in the metal consumption of sewing machines as a whole. For experimental studies, special sieves were made: plastic with chamfered, plastic with standard holes and plastic with rounded edges. The dependences of the completeness of separation of the procode fraction ε were determined for various combinations of the angle of inclination α and the rotation frequency of the working body ω for various seed thicknesses. The angle of inclination of the working body α was changed from 4 ° to 12 °, in increments of 2 °, rotation frequency ω from 400 min--to 1200 min-¹, in increments of 200 min-¹. The size gap was set taking into account the dimensional characteristics of existing sieves with rectangular holes and was 0.2 mm. Studies were conducted on the seeds of common pine.