Fibre flax is a waste-free crop because a wide range of products is produced from flax raw materials (flax fiber, seeds) and its waste (flax shive). During flax harvesting, it is important to ...preserve the flax yield without losing and deteriorating quality properties. Fibre flax harvesting technology depends on different factors, such as the method of flax retting, the method of flax straw primary processing, the requirements for flax raw materials, and the weather conditions. Fibre flax pulling and flax band forming are important processes of traditional flax harvesting technologies, which have a strong influence on subsequent technological processes. Morphological characteristics, physical and mechanical properties, and technological parameters of fiber flax, and soil and weather conditions during harvesting have significantly affected flax pulling and technological parameters of the flax band. Knowledge of flax characteristics, properties and parameters, and harvesting technologies allows us to obtain flax raw materials with high-quality properties and reduce flax yield losses.
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•The compound microbial agents can affect the generation of metabolites.•Fatty acids were the main metabolites during flax retting.•The addition of compound microbial agents can ...reduce environmental pollution.•The compound microbial agents can positively regulate the retting process of flax.
In this study, 16S rRNA sequencing and GC–MS (gas chromatography–mass spectrometry) techniques were employed to examine the relationship between bacterial succession and metabolite alterations during the dew retting process of flax. The results indicated that the addition of compound microbial agents may affect the production and transformation of metabolites by re-establishing bacterial communities and promoting the degradation of pectic substances and the release of metabolites, and the best retting effect was achieved under the combined addition (BA). In addition, Chryseobacterium, Bacillus, and Pseudoonas were closely associated with the production of fatty acids and alcohols; the addition of compound microbial agents increased the content of critical metabolites while decreasing the environmental pollutant bis(2-ethylhexyl) phthalate. In summary, the addition of compound microbial agents can positively regulate the retting process of flax, shorten the retting cycle, improve the quality of flax fibre, and reduce the pollution of the environment.
Flaxseeds are a functional food representing, by far, the richest natural grain source of lignans, and accumulate substantial amounts of other health beneficial phenolic compounds (i.e., flavonols, ...hydroxycinnamic acids). This specific accumulation pattern is related to their numerous beneficial effects on human health. However, to date, little data is available concerning the relative impact of genetic and geographic parameters on the phytochemical yield and composition. Here, the major influence of the cultivar over geographic parameters on the flaxseed phytochemical accumulation yield and composition is evidenced. The importance of genetic parameters on the lignan accumulation was further confirmed by gene expression analysis monitored by RT-qPCR. The corresponding antioxidant activity of these flaxseed extracts was evaluated, both in vitro, using ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and iron chelating assays, as well as in vivo, by monitoring the impact of UV-induced oxidative stress on the lipid membrane peroxidation of yeast cells. Our results, both the in vitro and in vivo studies, confirm that flaxseed extracts are an effective protector against oxidative stress. The results point out that secoisolariciresinol diglucoside, caffeic acid glucoside, and
-coumaric acid glucoside are the main contributors to the antioxidant capacity. Considering the health benefits of these compounds, the present study demonstrates that the flaxseed cultivar type could greatly influence the phytochemical intakes and, therefore, the associated biological activities. We recommend that this crucial parameter be considered in epidemiological studies dealing with flaxseeds.
Main conclusion
Upregulation of the terpenoid pathway and increased ABA content in flax upon
Fusarium
infection leads to activation of the early plant’s response (PR genes, cell wall remodeling, and ...redox status).
Plants have developed a number of defense strategies against the adverse effects of fungi such as
Fusarium oxysporum
. One such defense is the production of antioxidant secondary metabolites, which fall into two main groups: the phenylpropanoids and the terpenoids. While functions and biosynthesis of phenylpropanoids have been extensively studied, very little is known about the genes controlling the terpenoid synthesis pathway in flax. They can serve as antioxidants, but are also substrates for a plethora of different compounds, including those of regulatory functions, like ABA. ABA’s function during pathogen attack remains obscure and often depends on the specific plant-pathogen interactions. In our study we showed that in flax the non-mevalonate pathway is strongly activated in the early hours of pathogen infection and that there is a redirection of metabolites towards ABA synthesis. The elevated synthesis of ABA correlates with flax resistance to
F. oxysporum
, thus we suggest ABA to be a positive regulator of the plant’s early response to the infection.
Flax is valued for its fiber, seed oil and nutraceuticals. Recently, the fiber industry has invested in the development of products made from linseed stems, making it a dual purpose crop. ...Simultaneous targeting of genomic regions controlling stem fiber and seed quality traits could enable the development of dual purpose cultivars. However, the genetic diversity, population structure and linkage disequilibrium (LD) patterns necessary for association mapping (AM) have not yet been assessed in flax because genomic resources have only recently been developed. We characterized 407 globally distributed flax accessions using 448 microsatellite markers. The data was analyzed to assess the suitability of this core collection for AM. Genomic scans to identify candidate genes selected during the divergent breeding process of fiber flax and linseed were conducted using the whole genome shotgun sequence of flax.
Combined genetic structure analysis assigned all accessions to two major groups with six sub-groups. Population differentiation was weak between the major groups (F(ST) = 0.094) and for most of the pairwise comparisons among sub-groups. The molecular coancestry analysis indicated weak relatedness (mean = 0.287) for most individual pairs. Abundant genetic diversity was observed in the total panel (5.32 alleles per locus), and some sub-groups showed a high proportion of private alleles. The average genome-wide LD (r²) was 0.036, with a relatively fast decay of 1.5 cM. Genomic scans between fiber flax and linseed identified candidate genes involved in cell-wall biogenesis/modification, xylem identity and fatty acid biosynthesis congruent with genes previously identified in flax and other plant species.
Based on the abundant genetic diversity, weak population structure and relatedness and relatively fast LD decay, we concluded that this core collection is suitable for AM studies targeting multiple agronomic and quality traits aiming at the improvement of flax as a true dual purpose crop. Our genomic scans provide the first insights into candidate regions affected by divergent selection in flax. In combination with AM, genomic scans have the ability to increase the power to detect loci influencing complex traits.
In a preceding microcosm study, we found huge differences in phosphorus (P) acquisition in sorghum (Sorghum bicolor) and flax (Linum usitatissimum) sharing a common mycorrhizal network (CMN). Is the ...transcriptional regulation of arbuscular mycorrhizal (AM)‐induced inorganic orthophosphate (Pi) transporters responsible for these differences? We characterized and analyzed the expression of Pi transporters of the Pht1 family in both plant species, and identified two new AM‐inducible Pi transporters in flax. Mycorrhizal Pi acquisition was strongly affected by the combination of plant and AM fungal species. A corresponding change in the expression of two AM‐inducible Pht1 transporters was noticed in both plants (SbPT9, SbPT10, LuPT5 and LuPT8), but the effect was very weak. Overall, the expression level of these genes did not explain why flax took up more Pi from the CMN than did sorghum. The post‐transcriptional regulation of the transporters and their biochemical properties may be more important for their function than the fine‐tuning of their gene expression.
The physico-mechanical characteristics of fibers extracted from seven dual-purpose flax (DPF) and two fiber flax (FF) varieties grown in India were investigated to determine their suitability for ...various textile and technical applications. The selected varieties were evaluated in terms of the plant's phenotypic traits, maturity, fiber, and seed production. The flax fibers, after water retting, were examined for extent of retting, fiber mass loss, quantity, length, fineness, color, tenacity, and elongation. Fibers were characterized by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), Fourier Transform Infrared spectroscopy (FTIR), and X-ray diffractometry (×RD). Despite significant differences in phenotypic attributes among the nine varieties, except fiber tenacity, the difference in fineness, length, and elongation was found to be negligible. Thermo-chemical properties of the fibers also showed similarity across the nine varieties.
Flax (Linum usitatissimum L.) is one of the oldest predominant industrial crops grown for seed, oil and fiber. The present study was executed to evaluate the morpho-physiological traits, biochemical ...responses, gas exchange parameters and phytoextraction potential of flax raised in differentially copper (Cu) spiked soil viz (0, 200, 400 and 600 mg Cu kg−1 soil) under greenhouse pot experiment. The results revealed that flax plants were able to grow up to 400 mg kg−1 Cu level without showing significant growth inhabitation while, further inference of Cu (600 mg kg−1) in the soil prominently inhibited flax growth and biomass accumulation. Compared to the control, contents of proline and malondialdehyde (MDA) were increased by 160.0% and 754.1% accordingly, at 600 mg Cu kg−1 soil level. The Cu-induced oxidative stress was minimized by the enhanced activities of superoxide dismutase (SOD) by 189.2% and guaiacol peroxidase (POD) by 300.8% in the leaves of flax at 600 mg Cu kg−1 soil level, compared to the untreated control. The plant Cu concentration was determined at 35, 70, 105 and 140 days after sowing (DAS) and results depicted that 16.9 times higher Cu concentration was accumulated in flax roots while little (14.9 times) was transported to the shoots at early stage of growth, i.e. 35 DAS. While at 140 DAS, Cu was highly (21.7 times) transported to the shoots while, only 12.3 times Cu was accumulated in the roots at 600 mg Cu kg−1 soil level, compared to control. Meanwhile, Cu uptake by flax was boosted up to 253 mg kg−1 from the soil and thereby extracted 43%, 39% and 41% of Cu at 200, 400 and 600 mg Cu kg−1 soil level, compared to initial Cu concentration. Therefore, study concluded that flax has a great potential to accumulate high concentration of Cu in its shoots and can be utilized as phytoremediation material when grown in Cu contaminated soils.
•Flax (Linum usitatissimum L.) showed normal growth upto 400 mg kg−1 Cu but further implication of Cu caused reduction in growth.•The concentration of Cu in the tissues affect photosynthetic pigments and gaseous exchange attributes.•Cu was highly accumulated in the roots at earlier growth stage (35 DAS) while in the shoots at later growth stage (140 DAS).•Flax was capable to revoke higher Cu concentrations thus can be used as phytoremediation material in Cu contaminated soils.
Flax (
Linum usitatissimum
L.), one of the oldest cultivated crops, continues to be widely grown for oil, fiber and food. Furthermore, the plants show a metal tolerance dependent on species so is ...ideal for research. Present study was conducted to find out the influence of copper (Cu) toxicity on plant biomass, growth, chlorophyll content, malondialdehyde (MDA) contents, proline production, antioxidative enzymes and metal up taken by
L. usitatissimum
from the soil grown under mixing of Cu-contaminated soil with natural soil by 0:1 (control), 1:0, 1:1, 1:2 and 1:4. Results revealed that, high concentration of Cu in the soil affected plant growth and development by reducing plant height, plant diameter and plant fresh and dry biomass and chlorophyll contents in the leaves compared with the control. Furthermore, Cu in excess causes generation of reactive oxygen species (ROS) such as superoxide radical (O
–
) and hydroxyl radicals (OH), which is manifested by high malondialdehyde (MDA) and proline contents also. The increasing activities of superoxidase dismutase (SOD) and peroxidase (POD) in the roots and leaves of
L. usitatissimum
are involved in the scavenging of ROS. Results also showed that
L. usitatissimum
also has capability to revoke large amount of Cu from the contaminated soil. As Cu concentration in the soil increases, the final uptake of Cu concentration by
L. usitatissimum
increases. Furthermore, the soil chemical parameters (pH, electrical conductivity and cation exchange capacity) were increasing to highest levels as the ratio of Cu concentration to the natural soil increases. Thus, Cu-contaminated soil is amended with the addition of natural soil significantly reduced plant growth and biomass, while
L. usitatissimum
is able to revoke large amount of Cu from the soil and could be grown as flaxseed and a potential candidate for phytoremediation of Cu.
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