Membrane fatty acid compositions and cold-induced responses in tetraploid and hexaploid wheats

OsKASI-2 is required for the regulation of unsaturation levels of membrane lipids and chilling tolerance in rice

Chilling stress has seriously limited the global production and geographical distribution of rice. However, the molecular mechanisms associated with plant responses to chilling stress are less known. In this study, we revealed a member of β-ketoacyl-ACP synthase I family (KASI), OsKASI-2 which confers chilling tolerance in rice. OsKASI-2 encodes a chloroplast-localized KASI enzyme mainly expressed in the leaves and anthers of rice and strongly induced by chilling stress. Disruption of OsKASI-2 led to decreased KAS enzymatic activity and the levels of unsaturated fatty acids, which impairs degree of unsaturation of membrane lipids, thus increased sensitivity to chilling stress in rice. However, the overexpression of OsKASI-2 significantly improved the chilling tolerance ability in rice. In addition, OsKASI-2 may regulate ROS metabolism in response to chilling stress. Natural variation of OsKASI-2 might result in difference in chilling tolerance between indica and japonica accessions, and Hap1 of OsKASI-2 confers chilling tolerance in rice. Taken together, we suggest OsKASI-2 is critical for regulating degree of unsaturation of membrane lipids and ROS accumulation for maintenance of membrane structural homeostasis under chilling stress, and provide a potential target gene for improving chilling tolerance of rice.

Multi-scale characterisation of cold response reveals immediate and long-term impacts on cell physiology up to seed composition in sunflower

Early sowing can help summer crops escape drought and can mitigate the impacts of climate change on them. However, it exposes them to cold stress during initial developmental stages, which has both immediate and long-term effects on development and physiology. To understand how early night-chilling stress impacts plant development and yield, we studied the reference sunflower line XRQ under controlled, semi-controlled and field conditions. We performed high-throughput imaging of the whole plant parts and obtained physiological and transcriptomic data from leaves, hypocotyls and roots. We observed morphological reductions in early stages under field and controlled conditions, with a decrease in root development, an increase in reactive oxygen species content in leaves and changes in lipid composition in hypocotyls. A long-term increase in leaf chlorophyll suggests a stress memory mechanism that was supported by transcriptomic induction of histone coding genes. We highlighted DEGs related to cold acclimation such as chaperone, heat shock and late embryogenesis abundant proteins. We identified genes in hypocotyls involved in lipid, cutin, suberin and phenylalanine ammonia lyase biosynthesis and ROS scavenging. This comprehensive study describes new phenotyping methods and candidate genes to understand phenotypic plasticity better in response to chilling and study stress memory in sunflower.

Allyl Isothiocyanate Maintains DHA-Containing Glycerophospholipids and Ameliorates the Cognitive Function Decline in OVX Mice

Low-temperature-induced fatty acid desaturation is highly conserved in animals, plants, and bacteria. Allyl isothiocyanate (AITC) is an agonist of the transient receptor potential ankyrin 1 (TRPA1), which is activated by various chemophysiological stimuli, including low temperature. However, whether AITC induces fatty acid desaturation remains unknown. We showed here that AITC increased levels of glycerophospholipids (GP) esterified with unsaturated fatty acids, especially docosahexaenoic acid (DHA) in TRPA1-expressing HEK cells. Additionally, GP-DHA including phosphatidylcholine (18:0/22:6) and phosphatidylethanolamine (18:0/22:6) was increased in the brain and liver of AITC-administered mice. Moreover, intragastrical injection of AITC in ovariectomized (OVX) female C57BL/6J mice dose-dependently shortened the Δlatency time determined by the Morris water maze test, indicating AITC ameliorated the cognitive function decline in these mice. Thus, the oral administration of AITC maintains GP-DHA in the liver and brain, proving to be a potential strategy for preventing cognitive decline.

Comparative analysis of cold-responsive genes under short-term cold stimulation and cold-adaptive genes under long-term heterogeneous environments reveals a cold adaptation mechanism in weeping forsythia

Identifying cold-related genes can provide insights into the cold adaptation mechanism of weeping forsythia. In this study, we compared the changes in gene expressions and physiological and biochemical indices under short-term cold stimulation with the changes in gene sequences under a long-term heterogeneous environment to investigate the cold adaptation mechanism in weeping forsythia. The data of adaptive gene sequence changes, e.g., single nucleotide polymorphisms, were obtained from previous landscape genomics studies. The physiological and biochemical indicators and transcriptome results showed that weeping forsythia initiated a series of programs, including increasing cell osmotic pressures, scavenging ROS, activating the defense mechanism that crosses with pathogen infection, and upregulating CBF/DREB1 transcription factor 1, to cope with short-term cold stress. A reanalysis of landscape genomic data suggested that weeping forsythia responded to long-term heterogeneous cold stress by the differentiation of genes related to synthesis of aromatic substances and adenosine triphosphate. Our results supported the hypothesis that the adaptation mechanisms of species to short-term environmental stimulation and long-term stress in heterogeneous environments are different. The differences in cold tolerance among populations are not necessarily obtained by changing cold-responsive gene sequences. This study provides new insights into the cold adaptation mechanisms of plants.

Changes in the physicochemical parameters and microbial community of a new cultivar blue wheat cereal wholemeal during sourdough production

Changes in the characteristics of a new cultivar (DS8472-5) of blue wheat during wholemeal fermentation with Pediococcus acidilactici (LUHS29), Liquorilactobacillus uvarum (LUHS245), and Lactiplantibacillus plantarum (LUHS122), including acidity, microbiological and chromaticity parameters, free amino acid (FAA), gamma-aminobutyric acid (GABA), and biogenic amine (BA) contents, macro- and micro-element concentrations and fatty acid (FA) and volatile compounds (VC), were evaluated. In addition, a metagenomic analysis was performed. The lactic acid bacteria (LAB) strains used for fermentation was a significant factor in wholemeal fermentation sample pH, redness (a*) and LAB counts (p ≤ 0.05). In most of the samples, fermentation increased the FAA content in wheat wholemeal, and the highest concentration of GABA was found in DS8472-5 LUHS122 samples. Phenylethylamine (PHE) was found in all wheat wholemeal samples; however, spermidine was only detected in fermented samples and cadaverine only in DS8472-5 LUHS122. Fermented samples showed higher omega-3 and omega-6 contents and a higher number and variety of VC. Analysis of the microbial profile showed that LAB as part of the natural microbiota present in cereal grains also actively participates in fermentation processes induced by industrial bacterial cultures. Finally, all the tested LAB were suitable for DS8472-5 wheat wholemeal fermentation, and the DS8472-5 LUHS122 samples showed the lowest pH and the highest LAB viable counts (3.94, 5.80°N, and 8.92 log10 CFU/g, respectively).

Cold stress-induced changes in metabolism of carbonyl compounds and membrane fatty acid composition in chickpea

In this study, changes in membrane fatty acid (FA) composition and damage indices contents as well as the transcript patterns of carbonyl-detoxifying genes were evaluated in two chickpea (Cicer arietinum L.) genotypes, cold-tolerant Sel96th11439 and cold-sensitive ILC533 under cold stress (CS; 4 °C). During CS, H2O2 and malondialdehyde (MDA) contents increased (by 47% and 57%, respectively) in the sensitive genotype, while these contents remained unchanged in the tolerant genotype. In tolerant plants, higher content of linoleic, linolenic, unsaturated FAs (UFAs), total FAs and double bond index (DBI) (by 23, 21, 19, 17 and 9%, respectively) was observed at 6 days after stress (DAS) compared to sensitive plants, which, along with alterations of the damage indices, indicate their enhanced tolerance to CS. Compared with the sensitive genotype, less lipoxygenase (LOX) activity (by 59%) in the tolerant genotype was accompanied by decreased MDA and increased levels of UFAs and DBI during CS, particularly at 6 DAS. Upregulation of aldehyde dehydrogenase and aldo-keto reductase genes (by 9- and 10-fold, respectively) at 1 DAS, along with the enhanced transcript levels of aldehyde reductase and 2-alkenal reductase (by 3- and 14.7-fold, respectively) at 6 DAS were accompanied by increased UFAs and reduced MDA contents in the tolerant genotype. Overall, the results suggest that cold tolerance in chickpea was partly associated with regulation of membrane FA compositions and the potential metabolic networks involved in synthesis and degradation of carbonyl compounds.

The Potential of Traditional ‘Gaja’ and New Breed Lines of Waxy, Blue and Purple Wheat in Wholemeal Flour Fermentation

The aim of this study was to analyse and compare the acidity, microbiological and colour characteristics, fatty (FA) and amino (AA) acid profiles, biogenic amine (BA) and gamma-aminobutyric acid (GABA) concentrations, and macro- and microelement contents in non-treated (non-fermented) and fermented wholemeal cereal flours of ‘Gaja’ (traditional wheat) and new breed lines DS8888-3-6 (waxy wheat), DS8548-7 (blue wheat) and DS8535-2 (purple wheat). Independent fermentations were undertaken with selected strains of Pediococcus acidilactici, Liquorilactobacillus uvarum and Lactiplantibacillus plantarum. The results revealed that all the wholemeal cereal flours of the analysed wheat varieties are suitable for fermentation with the selected strains because all the fermented samples showed lactic acid bacteria (LAB) viable counts higher than 8.00 log10 CFU/g and desirable low pH values. In most of the cases, fermentation increased the concentration of essential amino acids in the wholemeal cereal samples, and the LAB strain used for fermentation proved to be a significant factor in all the essential amino acid content of wholemeal wheat (p ≤ 0.0001). When comparing the non-fermented samples, the highest GABA content was found in ‘Gaja’ and waxy wheat samples (2.47 µmol/g, on average), and, in all the cases, fermentation significantly increased GABA concentration in the wholemeal cereals. On the other hand, total levels of biogenic amines in wholemeal samples ranged from 22.7 to 416 mg/kg. The wheat variety was a significant factor in all the analysed macro- and microelement contents (p ≤ 0.0001) in the wholemeal cereals. Furthermore, fermentation showed to be a significant factor in most of the FA content of the wholemeal cereal samples. Finally, fermentation can also contribute to improving the biological and functional value of wholemeal wheat flours (by increasing essential amino acids and GABA concentrations); however, safety parameters (e.g., biogenic amines) also should be taken into consideration when optimizing the most appropriate technological parameters.

Genome-wide analysis of the DREB family genes and functional identification of the involvement of BrDREB2B in abiotic stress in wucai (Brassica campestris L.)

Dehydration responsive element binding protein (DREB) is a significant transcription factor class known to be implicated in abiotic stresses. In this study, we systematically conducted a genome-wide identification and expression analysis of the DREB gene family, including gene structures, evolutionary relationships, chromosome distribution, conserved domains, and expression patterns. A total of 65 DREB family gene members were identified in Chinese cabbage (Brassica rapa L.) and were classified into five subgroups based on phylogenetic analysis. Through analysis of the conserved domains of BrDREB family genes, only one exon existed in the gene structure. Through the analysis of cis-acting elements, these genes were mainly involved in hormone regulation and adversity stress. In order to identify the function of BrDREB2B, overexpressed transgenic Arabidopsis was constructed. After different stress treatments, the germination rate, root growth, survival rate, and various plant physiological indicators were measured. The results showed that transgenic Arabidopsis thaliana plants overexpressing BrDREB2B exhibited enhanced tolerance to salt, heat and drought stresses. Taken together, our results are the first to report the BrDREB2B gene response to drought and heat stresses in Chinese cabbage and provide a basis for further studies to determine the function of BrDREBs in response to abiotic stresses.

Comparison Study of Nontreated and Fermented Wheat Varieties 'Ada', 'Sarta', and New Breed Blue and Purple Wheat Lines Wholemeal Flour

The aim of this study was to analyze and compare the acidity, microbiological, and chromaticity parameters; fatty acid (FA) and volatile compound (VC) profiles; and biogenic amine (BA), macro- and microelement, and mycotoxin concentrations in nontreated ‘Ada’, ‘Sarta’, and new breed blue (DS8472-5) and purple (DS8526-2) wheat lines wholemeal (WW) with those fermented with lactic acid bacteria (LAB) possessing antimicrobial/antifungal properties, isolated from spontaneous sourdough: Pediococcus acidilactici-LUHS29, Liquorilactobacillus uvarum-LUHS245, Lactiplantibacillus plantarum-LUHS122). All the fermented WW showed >8.0 log10 CFU/g of LAB count, and the type of LAB was a significant factor in the WW acidity parameters. Phenylethylamine was the predominant BA in WW, and the wheat variety (WV), the type of LAB, and their interaction were significant factors on the BA formation. Despite the fact that some differences in trace element concentrations in WW were obtained, in most of the cases fermentation was not a significant factor in their content. The main FAs in WW were palmitic acid, all-cis,trans-octadecenoic acid, and linoleic acid. Fermented WW showed a more diverse VC profile; however, the influence of fermentation on deoxynivalenol in WW was varied. Finally, further studies are needed to indicate the technological parameters that would be the most effective for each WV, including the lowest BA formation and mycotoxin degradation.

Significance of Lipid Fatty Acid Composition for Resistance to Winter Conditions in Asplenium scolopendrium

Simple Summary

Plants growing at temperate and polar latitudes are exposed to cold stress. With climate change, different durations of low temperatures and sometimes frost are being increasingly observed in regions at low latitudes. This can cause especially great harm to agricultural crops, the mortality of which can pose a serious challenge to the food supply for the global population. One of the factors affecting plant resistance to low and negative temperatures is specific changes in the fatty acid (FA) composition of lipids. It should be noted that most of the crops studied in this regard are angiosperms. It is known that the FA composition of angiosperms has undergone significant evolutionary changes compared to that of nonflowering vascular plants. Studying the FA composition of various taxonomic groups can shed light on and reveal new mechanisms of plant resistance. Therefore, in this paper, we focused on the rare evergreen fern Asplenium scolopendrium, whose fronds can tolerate freezing. A number of specific features of its FA composition were discovered, which, in combination with other resistance mechanisms, determine its ability to grow in temperate climate zones and safely undergo wintering.

Abstract

Ferns are one of the oldest land plants. Among them, there are species that, during the course of evolution, have adapted to living in temperate climates and under winter conditions. Asplenium scolopendrium is one such species whose fronds are able to tolerate low subzero temperatures in winter. It is known that the resistance of ferns to freezing is associated with their prevention of desiccation via unique properties of the xylem and effective photoprotective mechanisms. In this work, the composition of A. scolopendrium lipid fatty acids (FAs) at different times of the year was studied by gas–liquid chromatography with mass spectrometry to determine their role in the resistance of this species to low temperatures. During the growing season, the polyunsaturated FA content increased significantly. This led to increases in the unsaturation and double-bond indices by winter. In addition, after emergence from snow, medium-chain FAs were found in the fronds. Thus, it can be speculated that the FA composition plays an important role in the adaptation of A. scolopendrium to growing conditions and preparation for successful wintering.

Gas chromatographic method with minimal sample consumption for quality control of 13C-mixed triglycerides used in clinical diagnosis

Exocrine pancreatic insufficiency (EPI) can be comfortably diagnosed by a breath test using the mixed triglyceride 2-octanoyl (1-¹³C)-1,3 distearoyl glycerol (¹³C-MTG). However, it is not fully accepted as a routine test yet as no vendor provides a certified product for clinical applications. Current recommended methods for quality control of triglycerides are not compatible with the produced expensive small batches of ¹³C-MTG. In this article, two procedures were miniaturized and optimized: one to confirm the structure by a regiospecific enzymatic reaction and another to check the purity via a methyl esterification. Both pretreated samples were then analyzed by gas chromatography coupled to mass spectrometry (GC-MS). The proposed methods showed good selectivity for the structure confirmation and good linearity with external standards for the purity control: R² values were higher than 0.995, accuracy was in the 98-100% range and excellent repeatability (RSD <1.4%) was achieved.

Comparative analysis of drought-responsive and -adaptive genes in Chinese wingnut (Pterocarya stenoptera C. DC)

Background

Drought is the main stress factor for the cultivation of Pterocarya stenoptera in urban areas, and this factor will cause its dehydration and affect its growth. Identifying drought-related genes will be useful for understanding the drought adaptation mechanism of P. stenoptera.

Results

We used physiological indicator detection, comparative transcriptome sequencing, and reanalysis on the results of previous landscape genomics studies to investigate the drought adaptation mechanism in P. stenoptera. The changes in malondialdehyde content showed that P. stenoptera was remarkably affected by drought stress, and the increase in soluble sugar content suggested its important role in response to drought stress. Results of comparative transcriptome sequencing showed that P. stenoptera initiated a series of programs, such as increasing the gene expression of unsaturated fatty acids, tyrosine, and plant pathogen resistance, to deal with the transient drought stress. According to the annotated results in a previous study, P. stenoptera adapts to the long-term differential drought stress by regulating the thickness of cell walls and expressing upper or lower limits of the downstream genes in the hormone signaling pathway. Through the comparative analysis of drought-responsive and -adaptive genes in P. stenoptera, this study supports the hypothesis that the environment-responsive genes (ERGs) introduced by the transient environmental stresses will be substantially more than the environment-adaptive genes (EAGs) in response to long-term differential environmental stresses, and the EAGs are not necessarily ERGs.

Conclusions

Our study identified drought-responsive and -adaptive genes in P. stenoptera and revealed that P. stenoptera increased the gene expression of unsaturated fatty acids, tyrosine, and plant pathogen resistance in response to transient drought stress. This study reveals the different adaptation mechanism of P. stenoptera under the transient and long-term differential drought stresses.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-07470-z.

The effect of exogenous 24-epibrassinolide pretreatment on the quality, antioxidant capacity, and postharvest life of wucai (Brassica campestris L.)

The quality of green leafy vegetables is easily lost during the postharvest period. The effect of exogenous 24-epibrassinolide (EBR) pretreatment on the quality of wucai was evaluated in the present study. Wucai plants were sprayed twice with 0.1 μM EBR before harvesting. Two storage temperatures were tested: 25°C and 4°C. At 4°C, EBR pretreatment significantly delayed the degradation of the pigment and plant water loss. Furthermore, we measured the activity of key enzymes of the ascorbic acid (AsA)-glutathione (GSH) cycle, the content of the main metabolites, and the expression of the AsA metabolism-related genes in leaves. The results indicated that all three plants showed stronger antioxidant capacity after EBR pretreatment. At 4°C and 25°C, the storage time of wucai was 20 days and 7 days after EBR treatment, while the samples could be stored for 14 days and 4 days without EBR treatment application, respectively. At 4°C, the nutritional properties of wucai pretreated with EBR, such as total free amino acids, total soluble sugar, and cellulose contents, were higher than those of the control, while the content of nitrite and lignin was lower than that of the control. Hence, EBR pretreatment was able to enhance the antioxidant capacity of wucai, maintain normal leaf color and shape during storage, and delay the decline of nutritional properties; therefore, EBR pretreatment has potential commercial value for prolonging the market life of wucai.

Apple TIME FOR COFFEE contributes to freezing tolerance by promoting unsaturation of fatty acids

Freezing stress is a major environmental factor that threatens the growth and development of fruit trees. MdMYB88 and its paralogue MdMYB124 have been identified as pivotal regulators in apple (Malus × domestica) freezing stress tolerance. Here, we demonstrated that a target of MdMYB88 and MdMYB124, TIME FOR COFFEE (TIC), contributes to freezing tolerance in apple. MdMYB88 and MdMYB124 directly bound the MdTIC promoter and positively regulated its expression under cold conditions. MdTIC RNAi plants displayed reduced freezing tolerance when MdTIC expression was repressed. Moreover, MdTIC RNAi plants lowered antioxidant enzyme activity. Transcriptome profiling revealed altered expression of cold-responsive genes in MdTIC RNAi plants under cold conditions, including MdPLC2, MdMKK2, and MdICE1. We also discovered that disordered MdTIC expression changed the saturation of fatty acids. Taken together, our data suggest that MdTIC is required for apple to tolerate freezing by mediating the expression of cold-responsive genes and fatty acid composition.

Lipids Composition in Plant Membranes

The paper focuses on the selected plant lipid issues. Classification, nomenclature, and abundance of fatty acids was discussed. Then, classification, composition, role, and organization of lipids were displayed. The involvement of lipids in xantophyll cycle and glycerolipids synthesis (as the most abundant of all lipid classes) were also discussed. Moreover, in order to better understand the biomembranes remodeling, the model (artificial) membranes, mimicking the naturally occurring membranes are employed and the survey on their composition and application in different kind of research was performed. High level of lipids remodeling in the plant membranes under different environmental conditions, e.g., nutrient deficiency, temperature stress, salinity or drought was proved. The key advantage of lipid research was the conclusion that lipids could serve as the markers of plant physiological condition and the detailed knowledge on lipids chemistry will allow to modify their composition for industrial needs.

Variations of membrane fatty acids and epicuticular wax metabolism in response to oleocellosis in lemon fruit

Oleocellosis is a physiological disorder causing blemishes on fruit surface. This study investigated the influence of oleocellosis on the membrane fatty acids and wax in lemon fruit rinds at the morphological, physiological, metabolic and molecular levels by using a variety with a high incidence rate of oleocellosis (green lemon). Oleocellosis-damaged rinds showed loose and flaky wax layers with more fissures on the surface, as well as higher contents of C16 and C18 fatty acids and very long chain (VLC) fatty alkanes while lower contents of VLC fatty aldehydes. The main differentially expressed genes, including FabZ, FAD2 and SAD6 involved in the accumulation of C16 and C18 fatty acids and CER1 involved in the transformation of VLC fatty aldehydes to VLC fatty alkanes, were up-regulated by oleocellosis. These results indicate that oleocellosis accelerates the accumulation of membrane free fatty acids and transformation of VLC fatty aldehydes to VLC fatty alkanes.

Lipids and Fatty Acids in Italian Durum Wheat (Triticum durum Desf.) Cultivars

The level of variation in lipids and their fatty acids was determined in the grains of 10 popular durum wheat cultivars commercially grown in Central and Southern Italy. Samples were harvested for two consecutive years to account for differences due to changes in climatic conditions. Total fat content was determined by means of the International Association of Cereal Science and Technology (ICC) Standard Method No. 136, whereas the fatty acid profile was determined by gas chromatography. Total lipid content ranged from 2.97% to 3.54% dry basis (d.b.) in the year 2010 and from 3.10% to 3.50% d.b. in the year 2011, and the average value was 3.22% d.b. considering both years together. Six main fatty acids were detected in all samples in order of decreasing amounts: linoleic (C18:2) > palmitic (C16:0) ≈ oleic (C18:1) > linolenic (C18:3) > stearic (C18:0) > palmitoleic (C16:1). Significant variations in the levels of single acids between two years were observed for three samples. These results will be very useful in the updating of food composition databases in general and will help authorities to set proper quality standards for wholegrain flours and products where the germ should be preserved, considering also the recent interest of industry and consumers for these kinds of products.

Research Progress in Membrane Lipid Metabolism and Molecular Mechanism in Peanut Cold Tolerance

Early sowing has been extensively used in high-latitude areas to avoid drought stress during sowing; however, cold damage has become the key limiting factor of early sowing. To relieve cold stress, plants develop a series of physiological and biochemical changes and sophisticated molecular regulatory mechanisms. The biomembrane is the barrier that protects cells from injury as well as the primary place for sensing cold signals. Chilling tolerance is closely related to the composition, structure, and metabolic process of membrane lipids. This review focuses on membrane lipid metabolism and its molecular mechanism, as well as lipid signal transduction in peanut (Arachis hypogaea L.) under cold stress to build a foundation for explicating lipid metabolism regulation patterns and physiological and molecular response mechanisms during cold stress and to promote the genetic improvement of peanut cold tolerance.

Changes in Membrane Lipid Composition and Function Accompanying Chilling Injury in Bell Peppers

Bell peppers are vulnerable to low temperature (<7°C) and subject to chilling injury (CI). To elucidate the relationship between cell membrane lipid composition and CI, a membrane lipidomic approach was taken. In addition, we performed microstructural analysis and low-field nuclear magnetic resonance to better understand CI. We also monitored primary physiological metabolism parameters to explain lipidomics. Our study indicated that cellular structure damage was more serious at 4°C, mostly represented by damage to the plasmalemma and plastid degradation. Membrane lipidomic data analysis reveals monogalactosyldiacylglycerol, phosphatidylcholine, phosphatidylethanolamine and phosphatidic acid as crucial biomarkers during CI. Furthermore, the significant increase in proline, electrolyte leakage and phospholipase D in chilled fruits also proved that membrane lipid metabolism is involved in the response to low temperature stress. To our knowledge, this study is the first attempt to describe the CI mechanisms in bell peppers based on membrane lipidomics.

Metabolic acclimation of tetraploid and hexaploid wheats by cold stress-induced carbohydrate accumulation

Metabolic acclimation of plants to cold stress may be of great importance for their growth, survival and crop productivity. The accumulation carbohydrates associated with cold tolerance (CT), transcript levels for genes encoding related enzymes along with damage indices were comparatively studied in three genotypes of bread and durum wheats differing in sensitivity. Two (Norstar, bread wheat and Gerdish, durum wheat) were tolerant and the other, SRN (durum wheat), was susceptible to cold stress. During cold stress (-5°C for 24h), the contents of electrolyte leakage index (ELI) in Norstar and then Gerdish plants were lower than that of SRN plants, particularly in cold acclimated (CA) plants (4°C for 14days), confirming lethal temperature 50 (LT₅₀) under field conditions. Increased carbohydrate abundances in the cases of sucrose, glucose, fructose, hexose phosphates, fructan, raffinose, arabinose resulted in different intensities of oxidative stress in bread (Norstar) plants compared to durum plants (SRN and Gerdish) plants as well as in CA plants compared to non-acclimated (NA) ones under cold, indicating metabolic/regulatory capacity along with a decrease in ELI content and enhanced defense activities. A significant decrease in these carbohydrates, particularly sucrose, under cold in NA plants showed an elevated level of cell damage (confirmed by ELI) compared to CA plants. On the other hand, an increase in hexose phosphates, particularly in NA plants, indicated sucrose degradation along with greater production of glucose and fructose compared to CA plants. Under such conditions, a significant increase in transcript levels of sucrose synthase and acidic invertase confirmed these results. Under cold, the high ABA-containing genotypes like Norstar and then Gerdish, which were obvious in CA plants, partly induced relative acclimation of cells for acquisition of CT compared to SRN. These results reveal an important role of carbohydrate metabolism in creating CT in durum wheats (particularly in Gerdish) as well as bread wheat with possible responsive components in metabolic and transcript levels.