Flax Stem Research Articles

Influence of the Processes of Fluffing the Flax Stem Strips on the Structural Parameters of the Layer

Introduction. The efficiency of separating long flax fiber from the flax straw largely depends on the structural parameters of the layer of flax stems. Modern fluffers for flax strips create random distortions and intersection of the layer of flax stems under the pick-up drum. These disadvantages of existing machines are minimized in an experimental fluffer, in which a layer of flax stems moves over the pick-up drum with a kinematic mode indicator equal to one. Aim of the Article. The study is aimed at finding means and methods for preserving the structural parameters of the layer of flax stems when fluffing flax straw strips. Materials and Methods. Experimental studies were carried out according to existing and newly developed methods, and the analysis of flax fiber was carried out according to the current GOST standards. The experiments were carried out on the flax strips formed by the LC-4A flax harvester. After grass sprouted through the strips of flax stems, they were fluffed with the serial machine VL-3 and an experimental fluffer. For each variant, the necessary measurements of the main structural parameters of the stem strip and collection of samples for analysis were made before the unit passed and after fluffering the flax stem strip. The results of measurements and processing of samples were processed using the methods of mathematical statistics. Results. It was found that macro-bends of the original and processed flax strips were in all the experiments. At the same time, the range of changes in the curvature of the flax strip outside the cutoff frequencies expanded 2.3 times under the influence of the working tools of the serial tedder VL-3. The randomness of these pulsations was caused by an increase in the distortion and elongation of the flax stems in the strip by 6.0° and 6.9%, respectively. At the same time, the experimental fluffer produced the smallest changes in the structural parameters of the flax stem layer. The technological evaluation of the flax straw confirmed the advantages of the experimental fluffer in comparison with the serial VL-3, which has an average production of long fiber higher by 0.65% and 0.5 units of number. Discussion and Conclusion. The analysis of the obtained results indicates the practicability of fluffing flax strips by picking up and moving the stems from above the pick-up drum with its kinematic mode index equal to one.

The NAC transcription factor LuNAC61 negatively regulates fiber development in flax (Linum usitatissimum L.)

Flax is a crucial fiber crop that exhibits excellent textile properties and serves as a model plant for investigating phloem fiber development. The regulation of multiple genes significantly influences fiber development, notably involving NAC (NAM, ATAF1/2, CUC2) transcription factors in forming the fiber secondary cell wall (SCW). Overexpression of LuNAC61 in flax resulted in sparse top meristematic zone leaves and significantly reduced stem cellulose content. Scanning electron microscopy and staining observations revealed a significant reduction in fiber bundles. β-Glucuronidase (GUS) staining analysis demonstrated high activity of the LuNAC61 promoter in the bast fibers of the flax stem. Additionally, several members of the LuPLATZ and LuCesA families exhibited significant coexpression with LuNAC61. Subcellular localization indicated the presence of LuPLATZ24 protein in the nucleus and cytoplasm, LuNAC61 protein exclusively in the nucleus, and LuCesA10 in the nucleus and endoplasmic reticulum. LuPLATZ24 positively regulates LuNAC61, whereas LuNAC61 negatively affects LuCesA10, suggesting the involvement of a metabolic network in regulating flax fiber development. In conclusion, this study provides a critical opportunity for a comprehensive and in-depth analysis of the mechanisms governing flax fiber development and the potential use of biotechnology to enhance flax fiber yield.

Development of the biomechanical system of the flax stem: Mutual game of primary and secondary growth

Flax is one of the oldest cultivated plants and one of the most important fiber crops in the world. Thousands of years of selection have resulted in the unique biomechanics of this plant, the principles of which are not yet fully understood. Detailed anatomical analysis of flax stems at different heights and at different stages of plant development (herringbone, fast growth, flowering) allowed us to follow the dynamics of primary and secondary growth of these plants. The evaluation of the mechanical properties of the stems and their individual parts at the same stages made it possible to identify the tissues that take on the main mechanical load at different periods of the plant’s life. In the younger parts of the stems, this tissue is the fiber-enriched phloem, whose fibers rapidly acquire a considerable elastic modulus. Xylem, which takes longer to develop, provides the main mechanical load in more mature parts of the stems and at later stages of plant development. Fast growth of flax stems occurs against the background of delayed xylem development. The onset of cell wall thickening in phloem fibers (the position of the snap point) is not determined by the mass of the plant part above it. The results obtained highlight the contribution of different tissues to the functioning of the plant as a holistic biomechanical system.

Short Flax Fibres and Shives as Reinforcements in Bio Composites: A Numerical and Experimental Study on the Mechanical Properties.

The complete flax stem, which contains shives and technical fibres, has the potential to reduce the cost, energy consumption and environmental impacts of the composite production process if used directly as reinforcement in a polymer matrix. Earlier studies have utilised flax stem as reinforcement in non-bio-based and non-biodegradable matrices not completely exploiting the bio-sourced and biodegradable nature of flax. We investigated the potential of using flax stem as reinforcement in a polylactic acid (PLA) matrix to produce a lightweight, fully bio-based composite with improved mechanical properties. Furthermore, we developed a mathematical approach to predict the material stiffness of the full composite part produced by the injection moulding process, considering a three-phase micromechanical model, where the effects of local orientations are accounted. Injection moulded plates with a flax content of up to 20 V% were fabricated to study the effect of flax shives and full straw flax on the mechanical properties of the material. A 62% increase in longitudinal stiffness was obtained, resulting in a 10% higher specific stiffness, compared to a short glass fibre-reinforced reference composite. Moreover, the anisotropy ratio of the flax-reinforced composite was 21% lower, compared to the short glass fibre material. This lower anisotropy ratio is attributed to the presence of the flax shives. Considering the fibre orientation in the injection moulded plates predicted with Moldflow simulations, a high agreement between experimental and predicted stiffness data was obtained. The use of flax stems as polymer reinforcement provides an alternative to the use of short technical fibres that require intensive extraction and purification steps and are known to be cumbersome to feed to the compounder.

Flax Harvesting Technologies for Flax Harvesting Machines

The technology of flax harvesting depends on input impacts, including: flax harvester qualitative characteristics; working body parameters; indicators of working conditions; intervening variables reflecting the dynamic properties of the working bodies and the dynamics of the flax flow input. (Research purpose) To establish patterns and the degree of correlation between the qualitative operation indicators (pulling and deseeding quality, flax line stretching); design parameters; machine dynamic properties and harvesting conditions (height and density of flax stem, field surface, thickness and unevenness of flax straw, etc.). (Materials and methods) Based on system analysis, mathematical models of the technological process of flax harvesting were developed. Information models were introduced for examining the main flax harvesters. (Results and discussion) The paper shows that the most typical indicators of the flax harvester working conditions are the flax stem height l(t), centimeters; the seed pod area a(t), centimeters; and field surface roughness z(t), centimeters. It is found that the quality of operation is determined by the deseeding quality, percentages; the flax straw stretching, times; the location of its apical and root parts, centimeters. The estimated indicators are as follows: the pulling height h(t), centimeters, the vibrations of the combine in the longitudinal-vertical plane Q(t), degrees, the location of the apical part of the flax flaw in front of the stripper. (Conclusions) A hydraulic device was developed to adjust the pulling height from 10 to 40 centimeters, depending on the flax stem. An important reserve for increasing the deseeding quality is the change in the width of the deseeding zone of the Vk harvester, centimeters. For this purpose, a mechanism was created for moving the deseeder against the clamping conveyor, depending on the flax stem height l(t), centimeters.

LOW-QUALITY FLAX STRAW BIOMASS HARVESTING FOR SUBSEQUENT USE AS FUEL: A REVIEW

Unfavorable conditions for flax growing, harvesting and dew-retting are the reason for the low-quality flax biomass production. This biomass cannot be processed for fiber or other purposes. Therefore, flax straws are burned in the fields or are used as fertilizer by plowing into the soil, which are not good solutions for the environment and subsequent cultivation operations. The limit values of quality properties of fibre flax stem, flax straw and retted straw for their processing are summarized, which can be used to determine the suitability of flax straw biomass for processing or burning. Low-quality flax biomass is inexpensive, ecofriendly and renewable, it can be used as solid fuel for heating greenhouses or buildings located near the field where the flax is grown. Various techniques of fibre flax and oilseed flax harvesting are presented in the article. The technique of low-quality flax harvesting is recommended, which include flax pulling out or flax cutting, flax threshing, flax straw windrow forming, flax straw natural drying on the field in natural way, flax bale forming, flax bale transporting, flax bale burning. This harvesting technology can be used for low-quality fibre flax and oilseed flax. Flax straw biomass can be baled into three bale types: small rectangular bales, big round bales, and big square bales The main requirements for fuel flax biomass bales are recommended. The boiler for burning flax straw bales must be chosen taking into account the shape and size of the bales. For the efficient operation of boilers, it is necessary to take into account the recommended values ​​of bale bulk density and moisture content of flax biomass.

Studying the Innovative Flax Pulling Process in Apparatuses with Transverse Pulling Channels

Introduction. During fiber-flax harvesting, the working tools of pulling units actively interact with the flax plants. The flax pulling unit with transverse tape-disc pulling channels is characterized by the separation of technological plant flows resulting in the loss of seeds and damage to the flax stems. The aim of the work is the theoretical and experimental substantiation of changes in the design of the pulling units with transverse tape-disc pulling channels by eliminating the separation of technological plant flows during flax pulling. Materials and Methods. Experimental studies to substantiate the parameters and modes of the pulling unit operation were carried out according to available and newly developed methodologies, while the evaluation of flax products was carried out according to current GOSTs (Russian National standards). There was determined the influence of the flax ripeness stages, flax yield, and a type of pulling unit on the indicators of separation of technological plant flows and on seed losses. The influence of the pulling unit type, operating width of the pulling section, and the pulling unit speed on the indicators of processing flax straw was also established. Results. There was obtained the dependence for determining the flax stem base elongation, taking into account the seed boll cohesion. The design of the modernized flax pulling unit was used to assess the effect of reducing the flax stem base elongation and eliminating the separation of technological plant flows during pulling on the reduction of seed loss and increase in the yield of flax longs. In the improved flax harvester, the frame elements are positioned behind the pulling unit. Thanks to the modernization of the pulling unit, the flax straw was of higher quality: 1.5 numbers at THLN-1.9M and 1.25 numbers at THLN-1.9P. Discussion and Conclusion. The modernized pulling unit THLN-1,9M during flax harvesting in the stage of early yellow ripeness, compared with the unit THLN-1,9P, can reduce seed loss by 1.4-2.0%, increased output of long fiber by 1.3%. The production of flax longs increases to 0.45 of its number.

On the origin of bast fiber dislocations in flax

Bast fibers of many fiber crops are valuable raw material for diverse applications. The isolated from flax stem technical fibers demonstrate numerous defects that are considered to accumulate both during plant growth and various steps of crop processing. We have performed quantitative estimation of dislocations in flax bast fibers within stems of developing plants and at different stages of stem processing, including drying in sheaves, dew retting, scutching and hackling. Scanning electron microscopy revealed no dislocations in fibers within the stem. Numerous defects appeared after scutching in ex-planta fibers and increased in frequency during subsequent technological step. We propose the disturbance of flax stem integrity and the mechanical treatments acting directly on fibers to serve the main factors of fiber deformation emergence.

Evolution of the flax cell wall composition during development and after gravitropism by synchrotron fluorescence imaging

Flax (Linum usitatissimum) lodging is an issue of great interest for industrial producers due to its economic impact; despite a strong varietal selection over around one century, this plant remains sensitive to lodging which represents a main technico-economic issue. To better understand lodging effects at the cell wall and stem scale, the cell wall composition dynamics during cell wall development and after a 90° tilt bending stress is reported. Deep-UltraViolet (DUV) fluorescence emission dynamics recorded at the Synchrotron SOLEIL-DISCO beamline by multichannel autofluorescence imaging is addressed for five cellular wall types of flax stems after an artificially induced gravitropic reaction. The quantitative fluorescent profile intensities were computed after image analysis, and compared to the control flax stems, we reported a systematically higher average intensity fluorescence (probability >95%) for the 90° tilted plants. Moreover, the average stem fluorescence intensities were significantly different among the 3 developmental stages, with the youngest stage (VS) exhibiting on average 30% and 20% less fluorescence than the medium (FG) and mature (M) stages, respectively. The flax stem response to tilt impacted the xylem cellular type, while the bast fibres were arguably less affected by the protein, and hydroxycinnamate contents. A complementary investigation was carried out on bast fibres by infrared microspectroscopy to explore the polysaccharide components not detected in DUV fluorescence, and significant modifications were monitored.

Comparative Transcriptomic Analysis Identifies Key Cellulose Synthase Genes (CESA) and Cellulose Synthase-like Genes (CSL) in Fast Growth Period of Flax Stem (Linum Usitatissimum L.)

ABSTRACT The cellulose synthase gene superfamily is vital for cell wall biogenesis during plant growth, particularly for flax fiber development. This study performed asequencing search of key CESA and CSL genes from several flax stem parts at different fiber development stages by comparing RNA-Seq. Quantitative RT-PCR was used to validate the expression of these genes. This study revealed that CESA4 genes (Lus10008225.g and Lus10008226.g), CESA6 genes (Lus10006161.g and Lus10041063.g), CESA8 genes (Lus10007296.g and Lus10029245.g), CSLD4 gene (Lus10026568.g), CSLE1 (Lus10016625.g) and CSLG genes (Lus10023056.g and Lus10023057.g) were specifically expressed in stem below the snap point where fibers is increased amounts of secondary cell wall deposition. LusCESA4 genes, LusCESA8, genes and LusCSLD4 gene were specifically expressed in fiber development stage during the fast growth period of flax plants. Based on GO and KEGG analyses, it was found that genes involved in pathways of cellulose microfibril organization, galactosyl transferase activity and galactose metabolism were specifically enriched in the stem tissue of the fiber development stage. Other genes involved in cellulose biosynthesis and cell wall development were also analyzed and discussed. The results will provide an important foundation for understanding fiber cell wall biogenesis, particularly the roles of LusCESAs and LusCSLs in the process of fiber development.

Expression Characteristics Analysis of CesA/Csl genes in Flax During the Fast Growing Stage

ABSTRACT Expression characteristics of predicted CesA/Csl genes of fiber flax variety ‘Diana’ were investigated using RNA-seq data obtained during the fast-growing stage. First, flax stem anatomic analysis revealed differing developmental processes from bottom to top, with middle and lower stem fiber cells exhibiting significantly thickened cell walls. Moreover, stem cellulose/hemicellulose content exhibited positional biases, with a top-to-bottom increase in cellulose content and bottom-to-top increase in hemicellulose content observed. Most CesA/Csl genes were predominantly expressed in stems, roots, and less in leaves. The correlations between the expression levels of CesA/Csl genes and the contents of cellulose and hemicellulose were analyzed. The expression levels of LuCesA4, LuCesA8A and LuCesA8B genes showed significantly positive correlations with cellulose content (P < 0.05), while expression levels of two LuCesA3, three LuCesA6, two LuCslA2, and four LuCslC genes revealed significantly positive correlations with hemicellulose content (P < 0.05). CesA/Csl protein interaction network analysis revealed five transcription factors (TFs) that had high protein–protein interaction (PPI) scores with CesA/Csl proteins: LuNAC10 (Lus10015392), LuNAC12 (Lus10001664), LuNAM (Lus10017915), LuMyb42 (Lus10038913), LuMyb46 (Lus10027369). Therefore, these TFs may play critical regulatory roles in cellulose/hemicellulose synthesis. This study provides a theoretical foundation for investigating flax fiber cell wall synthesis and regulatory mechanisms.

Identification and Characterization of Differentially Expressed microRNAs and Target Gene Related to Flax Stem Development

ABSTRACT Flax fiber was one of the earliest natural fibers utilized by humans. Current research on flax fiber development is mainly focused on functions of key genes, with few reports investigating regulation of microRNA expression. Here, miRNA-seq was employed to explore miRNA expression profiles of middle stem tissues of high-fiber flax variety Agatha-MB and low-fiber flax variety White Flower during the rapid growth period (RGP) and mature green stage (MGS) to reveal miRNAs related to flax stem fiber development. The results revealed that 24 and 26 known miRNAs were identified that exhibited significant expression differences during MGSAgatha-MB-vs-RGPAgatha-MB and MGSWF-vs-RGPWF, respectively. Forty-one miRNA-target pairs exhibited inverse expression pattern changes as compared to our previously reported transcriptome profiling results. Pathway enrichment analysis of miRNA target genes showed that the plant hormone signal transduction pathway yielded the highest number of miRNA target genes in both varieties between the two developmental stages. To confirm the accuracy and reliability of these miRNA-seq results, qRT-PCR analysis of expression changes of six selected Lus-miRNA demonstrated similar trends as observed using miRNA-seq. These findings will enhance our understanding of miRNA regulatory mechanisms in flax stem development and will provide a foundation for future functional studies of these key miRNAs.

Gene Expression Patterns for Proteins With Lectin Domains in Flax Stem Tissues Are Related to Deposition of Distinct Cell Wall Types.

The genomes of higher plants encode a variety of proteins with lectin domains that are able to specifically recognize certain carbohydrates. Plants are enriched in a variety of potentially complementary glycans, many of which are located in the cell wall. We performed a genome-wide search for flax proteins with lectin domains and compared the expression of the encoding genes in different stem tissues that have distinct cell wall types with different sets of major polysaccharides. Over 400 genes encoding proteins with lectin domains that belong to different families were revealed in the flax genome; three quarters of these genes were expressed in stem tissues. Hierarchical clustering of the data for all expressed lectins grouped the analyzed samples according to their characteristic cell wall type. Most lectins differentially expressed in tissues with primary, secondary, and tertiary cell walls were predicted to localize at the plasma membrane or cell wall. These lectins were from different families and had various architectural types. Three out of four flax genes for proteins with jacalin-like domains were highly upregulated in bast fibers at the stage of tertiary cell wall deposition. The dynamic changes in transcript level of many genes for lectins from various families were detected in stem tissue over the course of gravitropic response induced by plant gravistimulation. The data obtained in this study indicate a large number of lectin-mediated events in plants and provide insight into the proteins that take part in tissue specialization and reaction to abiotic stress.

Reductive Catalytic Fractionation of Flax Shive over Ru/C Catalysts

Flax shive is the main waste (up to 70 wt %) in the production of flax fiber. It represents the lignified parts of the flax stem mainly in the form of small straws. Complex processing of such wastes is a significant problem due to the heterogeneity of the chemical structure of lignin. This article presents the results of reductive catalytic fractionation (RCF) of flax shive in ethanol and isopropanol at elevated temperatures (225–250 °C) in the presence of a bifunctional catalyst (Ru/C) and molecular hydrogen. This provides solvolytic depolymerization of lignin and hemicelluloses presented in flax shive. Catalytic hydrogenation effectively stabilizes the formed lignin intermediates and prevents repolymerization reactions producing the lignin fraction with a high degree of depolymerization. RCF of flax shive produces solid products with a high cellulose content and liquid products consisting mainly of monophenolic compounds. Furthermore, the effect of different characteristics (the ruthenium content, particle size, and support acidity) of the bifunctional catalysts containing ruthenium nanoparticles supported on mesoporous, graphite-like carbon material Sibunit®-4 on the yield and composition of the products of hydrogenation of flax shive in sub- and super-critical ethanol has been studied. Bifunctional catalysts Ru/C used in the RCF of flax shive increase its conversion from 44 to 56 wt % and the yield of monophenols from 1.1 to 10.2 wt % (based on the weight of lignin in the sample). Using the best Ru/C catalyst containing 3% of Ru on oxidized at 400 °C carbon support, the high degree of delignification (up to 79.0%), cellulose yield (up to 67.2 wt %), and monophenols yield (up to 9.5 wt %) have been obtained.

Using the roller threshing device for threshing fiber flax

The ways of increasing efficiency of the factory technology for harvesting fiber flax with threshing stem band from the rolls were studied. The experiment was carried out in stationary conditions with a moisture content of the source material of no more than 16%. A roller threshing device was proposed for separating the seed part of the crop from the stem before feeding stems into the fiber production line. The device ensures threshing of the fiber flax stem band over its entire width without using a separate clamping conveyor. The places where the seed heap descends from the roller threshing device while threshing flax stem band were identified. Quality indicators of the roller threshing device operation were obtained ensuring 100% threshing of the fiber flax band with a band compression force between the rollers of 16 kN. With this method of threshing, damage and crushing of seeds were not noted, the stems were evenly flattened along their entire length. Fractional composition of the threshed heap was determined during threshing of a fiber flax stem band between the rolls of the laboratory sample of a three-roll threshing device: loose seeds (50%), shells of capsules with fruitstalks (47), capsules with seeds (3), heap of leaves and stems (less than 1%). The results of the study in stationary conditions showed the expediency of using roller working bodies to separate the seed part of the crop from the stem part for the technical support of the factory technology for harvesting fiber flax. The use of roller working bodies in the design of threshing devices without a separate clamping conveyor allows to increase the quality and quantity of flax products obtained both in seeds and in fiber due to the improvement of the process of gentle flattening of the stem band between the rollers along its entire width. The concept of this roller threshing device is advisable to use when designing trailers and travelling flax harvesting machines for the implementation of a separate technology for harvesting fiber flax.

Effect of Nitrogen Fertilizer Rates and Plant Density on Straw, Fiber Yield and Anatomical Manifestations of Some Flax Cultivars

Two field experiments were carried out at the Experimental Farm at Gemmeiza Agriculture Research Station, Agricultural Research Center, Egypt, during two successive winter growing seasons of 2018/2019 and 2019/2020 to study the response of three flax cultivars, i.e. Sakha 3, Giza 11 and Giza 12 to three nitrogen fertilizer rates (30, 50 and 70 kg N/fed) and three plant densities (1500, 2000 and 2500 seeds/m2) and their effect on straw and fiber yield and its related traits as well as anatomical manifestations for flax stem at middle region. The experimental design was laid out using split-split plot design in four replications. Flax cultivars were distributed in the main plots, whereas nitrogen fertilizer rates were arranged at random in sub-plots and plant densities treatments were assigned at random in sub-sub plots. The sub-sub plot area was 9 m2. Sakha 3 cultivar significantly produced the maximum total plant height, technical stem length, total fiber percentage, fiber yield/plant, fiber yield/fed, fiber length and fiber fineness in both seasons. Meanwhile, the highest No. of basal branches/plant, straw yield/plant and straw yield/fed in both seasons were recorded with Giza 12 cultivar. Meanwhile, Giza 11 cultivar gave the thickness stem diameter in both seasons. Increasing nitrogen fertilizer rates from 30 to 70 kg N/fed caused significant increases in all straw and fiber yield and its related traits of flax, except fiber fineness was significantly decreased with increasing nitrogen rates in both seasons. Increasing plant densities from 1500 to 2500 seeds/m2 caused markedly increment in total plant height, technical stem length, straw yield/fed, total fiber percentage, fiber yield/fed, fiber length and fiber fineness during both seasons. On the other hand, No. of basal branches/plant, stem diameter, straw yield/plant and fiber yield/plant were significantly decreased by increasing plant densities during both seasons. The first order interactions between treatments Sakha 3 X 70 kg N/fed, Sakha 3 X 2500 seeds/m2 and 70 kg N/fed X 2500 seeds/m2 as well as the second order interaction between treatments Sakha 3 X 70 kg N/fed X 2500 seeds/m2 were significantly recorded the highest total plant height, technical stem length, fiber yield/fed and fiber length as compared with the others interactions in both seasons. While, the maximum fiber yield/fed were recorded from the first order interactions between treatments Sakha 3 X 70 kg N/fed, Sakha 3 X 2500 seeds/m2 and 70 kg N/fed X 2500 seeds/m2 as well as the second order interaction between treatments Sakha 3 X 70 kg N/fed X 2500 seeds/m2. Data illustrated an increase in each of total cross section area, cortex area, fiber area, xylem area, fiber index per plant, cortex % and xylem % in all flax cultivars under study (Sakha 3, Giza 11 and Giza 12) as affected by fertilized flax plants with 70 kg N/fed and plant density at 1500 seeds/m2. It could be concluded that Sakha 3 cultivar and fertilizing by 70 kg N/fed with plant density of 2500 seeds/m2 to maximizing fiber yield/fed and quality.

Розробка технологічної лінії отримання льнотрести

The intensification of one of the most energy-intensive processes - the process of drying the material - contributes both to the creation of energy-saving technologies for processing crop products, and to solving the problem of obtaining dried material of a given quality. The purpose of this study is to develop energy and resource-saving technology for industrial preparation of linen trusts. Previous studies have shown that extracting flax stalks with water before the lobe stage helps to reduce the time before the main phase of fermentation of pectin. The effect of hydrothermal treatment on the next impregnation increases with increasing temperature, especially sharply this increase occurs at temperatures above 60 0C. As a result of research, a thermobiological method of flax stem lobe was developed, which is the basis of a technological line combining the processes of flax straw lobe, washing, deodorization and drying of the obtained flax trust, followed by its hydrothermal treatment. The line operation mode is discrete-continuous. Processing of raw materials is carried out in the containers of a special design providing immersion of raw materials in liquid and its movement on technological operations. After loading, the container is placed in the tank of the first hydrothermal treatment, where it is in heated water at a temperature of 90 ... 95 0C. Next, the soaked raw material is reloaded into the tank of the second hydrothermal treatment to stop the microbiological process and high-quality washing of the material in heated water at a temperature of 50 ... 70 0C. Due to the intensification of the process 3 ... 5 times due to the creation of appropriate aerodynamic and thermal humidity modes, the three-tier conveyor unit is modernized into a single-belt one, in the last zones of which the linen trust is brought to conditioned humidity by steam-air treatment. Experimental-industrial inspection of the technological line showed that the total duration of the main process is reduced by 1.5 ... 2 times, the specific costs of heat, electricity, water are reduced (by 20 ... 30%) and the yield of long fiber is increased by 0.5 .. 1.0%) with the improvement of its quality indicators, the degree of mechanization of technological operations increases.

КОНЦЕПТУАЛЬНА МОДЕЛЬ ТЕХНОЛОГІЙ ПЕРЕРОБКИ СТЕБЕЛ ЛЬОНУ

У статті запропонована концептуальна модель комплексних технологій переробки стебел льону залежно від класифікаційних ознак стеблостою. Ситуація у вітчизняному льонарстві на сьогодні неоднозначна. Спостерігається значне зменшення виробництва льону на волокно і зростання виробництва льону на насіння. Також, на основі існуючих досліджень, можна стверджувати, що в Україні зростає інтерес до комплексної переробки луб’яних культур. Основними виробниками льону олійного в Україні є південні та східні області. Західна Україна традиційно вважається виробником льону-довгунця. Проте, за останні чотири роки на цих територіях з’явилось й стрімко зростає виробництво льону олійного. Дослідження показали значні відмінності між льоном олійним, який вирощений у різних природно-кліматичних умовах. Особливістю сортів льону олійного, вирощеного у вологих та прохолодних умовах, є значне збільшення довжини стебла. Висока урожайність стеблової частини ускладнює застосування традиційної технології збирання льону олійного, яка передбачає використання зернозбиральних комбайнів. Після видалення насіння на полі лишаються валки стебло-волокнистої маси, яка потребує подальшої переробки. Однак, агровиробники не мають відповідних технологій і засобів. У результаті проведених досліджень розроблена концептуальна модель ресурсозберігаючих технологій збирання стебел льону з одночасною переробкою стебло-волокнистої маси в продукцію різного функціонального призначення: малогабаритні паливні рулони, паливні брикети та волокно, залежно від класифікаційних ознак стебел льону. На її основі подані пропозиції щодо технологій збирання льону з одночасною обробкою стебел й переробкою стебло-волокнистої маси для агровиробників.

Transcriptome Analysis of Two Flax Varieties at Different Developmental Stages Reveals Significant Differential Expression of Genes Related to Stem Fiber Development

ABSTRACT Flax stem bast fiber, a natural raw material used to make textiles, possesses poor heat and dye resistance, excessive stiffness and low elasticity. To improve fiber quality and quantity, flax fiber development-related differentially expressed genes (DEGs) were identified using RNA-seq of middle stems of Agatha and White Flower varieties during the rapid growth period and mature green stage. There were 300 and 486 DEGs at two developmental stages between the two varieties, respectively. Comparisons of DEGs between developmental stages yielded 2504 DEGs for Agatha and 2986 DEGs for White Flower. Of these, 710 and 1182 DEGs were solely expressed in Agatha and White Flower, respectively. For both varieties, the plant circadian rhythm pathway yielded most DEGs, highlighting circadian rhythm regulation was important during flax fiber development. Notably, 59 transcription factors were uniquely expressed in Agatha, 73 in White Flower and 94 in both varieties. Expression of 15 cellulose synthase A genes in both varieties varied significantly between developmental stages. Expression patterns of eight DEGs measured using qRT-PCR confirmed RNA-seq results. Thus, several interesting genes described here warrant future molecular mechanistic studies to learn their roles in fiber formation toward improving flax fiber quality through molecular breeding. Abbreviations: 4CL: 4-coumarate-CoA ligase; AP2-EREBP: apetala2/ethylene-responsive element binding protein; ARR-B: arabidopsis response regulator-B; bHLH: basic helix-loop-helix; bZIP: basic region/leucine zipper motif; CAD: cinnamyl alcohol dehydrogenase; CCoAOMT: caffeoyl CoA O-methyltransferase; CesA: cellulose synthase A; COMT: catechol-o-methyl transferase; CPP: cysteine-rich polycomb-like protein; CSL: cellulase synthase-like; DEGs: differentially expressed genes; DeTFs: differentially expressed transcription factors; FHA: forkhead-associated domain; GDP: guanosine diphosphate; GTP: guanosine triohosphte; GO: gene ontology; HSF: heat shock transcription factor; KEGG: kyoto encyclopedia of genes and genomes; LOB: lateral organboundaries; Lus: linum usitatissimum; MGS: mature green stage; mTERF: mitochondrial transcription termination factor; MYB: v-myb avian myeloblastosis viral oncogene homolog; NAC: nam, ataf1-2 and cuc2; NCBI: national center for biotechnology information; OFP: ovate family proteins; PLATZ: plant A/T rich sequence-and zinc-binding protein; qRT-PCR: quantitative RT-PCR; QC: quality control; RGP: rapid growth period; SBP: squmosa promoter binding protein; SNP: single nucleotide polymorphisms; SRA: short read archive; TAZ: tafazzin; TCP: tb1, cyc and pcfs; TFs: transcription factors.

АНАЛІЗ РОБОТИ ВИВІДНОГО ПРИСТРОЮ ЛЬОНОЗБИРАЛЬНОЇ МАШИНИ

У статті наведено результати аналізу роботи вивідного пристрою льонозбиральної машини. Обґрунтовано окремі параметри вивідного пристрою льонозбиральної машини.