Coping with salinity stress: segmental group 7 chromosome introgressions from halophytic Thinopyrum species greatly enhance tolerance of recipient durum wheat.

Increased soil salinization, tightly related to global warming and drought and exacerbated by intensified irrigation supply, implies highly detrimental effects on staple food crops such as wheat. The situation is particularly alarming for durum wheat (DW), better adapted to arid/semi-arid environments yet more sensitive to salt stress than bread wheat (BW). To enhance DW salinity tolerance, we resorted to chromosomally engineered materials with introgressions from allied halophytic Thinopyrum species. "Primary" recombinant lines (RLs), having portions of their 7AL arms distally replaced by 7el1L Th. ponticum segments, and "secondary" RLs, harboring Th. elongatum 7EL insertions "nested" into 7el1L segments, in addition to near-isogenic lines lacking any alien segment (CLs), cv. Om Rabia (OR) as salt tolerant control, and BW introgression lines with either most of 7el1 or the complete 7E chromosome substitution as additional CLs, were subjected to moderate (100 mM) and intense (200 mM) salt (NaCl) stress at early growth stages. The applied stress altered cell cycle progression, determining a general increase of cells in G1 and a reduction in S phase. Assessment of morpho-physiological and biochemical traits overall showed that the presence of Thinopyrum spp. segments was associated with considerably increased salinity tolerance versus its absence. For relative water content, Na+ accumulation and K+ retention in roots and leaves, oxidative stress indicators (malondialdehyde and hydrogen peroxide) and antioxidant enzyme activities, the observed differences between stressed and unstressed RLs versus CLs was of similar magnitude in "primary" and "secondary" types, suggesting that tolerance factors might reside in defined 7el1L shared portion(s). Nonetheless, the incremental contribution of 7EL segments emerged in various instances, greatly mitigating the effects of salt stress on root and leaf growth and on the quantity of photosynthetic pigments, boosting accumulation of compatible solutes and minimizing the decrease of a powerful antioxidant like ascorbate. The seemingly synergistic effect of 7el1L + 7EL segments/genes made "secondary" RLs able to often exceed cv. OR and equal or better perform than BW lines. Thus, transfer of a suite of genes from halophytic germplasm by use of fine chromosome engineering strategies may well be the way forward to enhance salinity tolerance of glycophytes, even the sensitive DW.

The wheat pathogenesis-related protein (TdPR1.2) enhanced tolerance to abiotic and biotic stresses in transgenic Arabidopsis plants.

In plants, the pathogenesis-related (PR) proteins have been identified as important regulators of biotic and abiotic stresses. PR proteins branch out into 19 different classes (PR1-PR19). Basically, all PR proteins display a well-established method of action, with the notable exception of PR1, which is a member of a large superfamily of proteins with a common CAP domain. We have previously isolated and characterized the first PR1 from durum wheat, called TdPR-1.2. In the current research work, TdPR1.2 gene was used to highlight its functional activities under various abiotic (sodium chloride (100 mM NaCl) and oxidative stresses (3 mM H2O2), hormonal salicylic acid (SA), abscisic acid (ABA) and jasmonic acid (JA), and abiotic stresses (Botrytis cinerea and Alternaria solani). Enhancement survival index was detected in Arabidopsis transgenic plants expressing TdPR1.2 gene. Moreover, quantitative real-time reverse transcription PCR (qRT-PCR) analysis demonstrated induction of antioxidant enzymes such as catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD). It equally revealed a decrease of malondialdehyde (MDA) as well as hydrogen peroxide (H2O2) levels in transgenic Arabidopsis plants compared to control lines, confirming the role of TdPR1.2 in terms of alleviating biotic and abiotic stresses in transgenic Arabidopsis plants. Eventually, RT-qPCR results showed a higher expression of biotic stress-related genes (PR1 and PDF1.2) in addition to a downregulation of the wound-related gene (LOX3 and VSP2) in transgenic lines treated with jasmonic acid (JA). Notably, these findings provide evidence for the outstanding functions of PR1.2 from durum wheat which can be further invested to boost tolerance in crop plants to abiotic and biotic stresses.

Mixture design of α-pinene, α-terpineol, and 1,8-cineole: A multiobjective response followed by chemometric approaches to optimize the antibacterial effect against various bacteria and antioxidant activity.

α-Pinene, α-terpineol, and 1,8-cineole are compounds naturally present in essential oils, although their amounts vary from oil to oil. Although several studies have reported their antibacterial and antioxidant effects, there are few reports on the synergistic or antagonistic effects of their combinations. The objective of this study was to investigate the combined antibacterial effect of these three compounds. To our knowledge, this is the first report on the prediction of their optimal combination using the mixture design approach. The experimental antibacterial activity of the α-pinene, α-terpineol, and 1,8-cineole mixtures depended on the proportion of each compound in the mixture and the target strain, with minimum inhibitory concentrations (MIC) ranging from 0.31 to 1.85 mg/mL. Using the increased simplex-centroid mixture design, the mixture containing 0.33% of each molecule proved to be the most effective against Bacillus cereus and had the lowest MIC values. In addition, α-pinene, α-terpineol, and 1,8-cineole showed significant antioxidant activity against 2,2-picryl-1-hydrazyl radical (DPPH), with IC50 values of 24.53 ± 0.05, 65.63 ± 0.71, and 63.58 ± 0.01 µg/mL, respectively. Statistical planning and the development of utility profiles of the substance mixtures can predict the optimal composition that will exhibit the highest antibacterial activity against B. cereus as well as antioxidant properties. Furthermore, the synergistic effect of the mixtures can contribute significantly to their successful use as natural preservatives in various applications.

The thioredoxin h-type TdTrxh2 protein of durum wheat confers abiotic stress tolerance of the transformant Arabidopsis plants through its protective role and the regulation of redox homoeostasis.

The thioredoxins (Trxs) are ubiquitous and they play a crucial role in various biological processes like growth and stress response. Although the functions of Trxs proteins are described in several previous reports, the function of the isoform Trxh2 of durum wheat (Triticum durum L.), designated as TdTrxh2, in abiotic stress response still unknown. Thus, we aimed in this study the functional characterization of TdTrxh2 through its expression in yeast cells and Arabidopsis plants. Sequence analysis revealed that TdTrxh2 protein shared the conserved redox site with the other Trxh from other plant species. Under various abiotic stresses, TdTrxh2 was up-regulated in leaves and roots of durum wheat. Interestingly, we demonstrated that TdTrxh2 exhibit protective effect on LDH activity against various treatments. Besides, the expression of TdTrxh2 in yeast cells conferred their tolerance to multiple stresses. Moreover, transgenic Arabidopsis expressing TdTrxh2 showed tolerance phenotype to several abiotic stresses. This tolerance was illustrated by high rate of proline accumulation, root proliferation, low accumulation of reactive oxygen species like H2O2 and O2·-, and high antioxidant CAT and POD enzymes activities. All these findings suggested that TdTrxh2 promotes abiotic stress tolerance through the redox homoeostasis regulation and its protective role.

Genome-Wide Investigation and Expression Analysis of the Catalase Gene Family in Oat Plants (Avena sativa L.).

Through the degradation of reactive oxygen species (ROS), different antioxidant enzymes, such as catalase (CAT), defend organisms against oxidative stress. These enzymes are crucial to numerous biological functions, like plant development and defense against several biotic and abiotic stresses. However, despite the major economic importance of Avena sativa around the globe, little is known about the CAT gene's structure and organization in this crop. Thus, a genome-wide investigation of the CAT gene family in oat plants has been carried out to characterize the potential roles of those genes under different stressors. Bioinformatic approaches were used in this study to predict the AvCAT gene's structure, secondary and tertiary protein structures, physicochemical properties, phylogenetic tree, and expression profiling under diverse developmental and biological conditions. A local Saudi oat variety (AlShinen) was used in this work. Here, ten AvCAT genes that belong to three groups (Groups I-III) were identified. All identified CATs harbor the two conserved domains (pfam00199 and pfam06628), a heme-binding domain, and a catalase activity motif. Moreover, identified AvCAT proteins were located in different compartments in the cell, such as the peroxisome, mitochondrion, and cytoplasm. By analyzing their promoters, different cis-elements were identified as being related to plant development, maturation, and response to different environmental stresses. Gene expression analysis revealed that three different AvCAT genes belonging to three different subgroups showed noticeable modifications in response to various stresses, such as mannitol, salt, and ABA. As far as we know, this is the first report describing the genome-wide analysis of the oat catalase gene family, and these data will help further study the roles of catalase genes during stress responses, leading to crop improvement.

Genome-Wide Identification and Expression Profiling of Pathogenesis-Related Protein 1 (PR-1) Genes in Durum Wheat (Triticum durum Desf.).

Pathogen-related proteins (PRs) are diversified proteins with a low molecular weight implicated in plant response to biotic and abiotic stress as well in regulating different functions in plant maturation. Interestingly, no systematical study has been conducted in durum wheat (Triticum turgidum subsp. durum). In the present study, 12 PR-1 genes encoding a CAP superfamily domain were identified in the genome of Triticum turgidum subsp. durum, which is an important cereal, using in silico approaches. Additionally, phylogenetic analysis showed that the PR-1 genes were classified into three groups based on their isoelectric point and the conserved motif domain. Moreover, our analysis showed that most of the TdPR-1 proteins presented an N-terminal signal peptide. Expression patterns analysis showed that the PR-1 gene family presented temporal and spatial specificity and was induced by different abiotic stresses. This is the first report describing the genome-scale analysis of the durum wheat PR-1 gene family, and these data will help further study the roles of PR-1 genes during stress responses, leading to crop improvement.

Identification of a putative kinase interacting domain in the durum wheat catalase 1 (TdCAT1) protein.

Catalases are crucial antioxidant enzymes that regulate plants responses to different biotic and abiotic stresses. It has been previously shown that the activities of durum wheat catalase proteins (TdCAT1) were stimulated in the presence of divalent cations Mn2+, Mg2+, Fe2+, Zn2+, and Ca2+. In addition, TdCAT1s can interact with calmodulins in calcium-independent manner, and this interaction stimulates its catalytic activity in a calcium-dependent manner. Moreover, this activity is further enhanced by Mn2+ cations. The current study showed that wheat catalase presents different phosphorylation targets. Besides, we demonstrated that catalase is able to interact with Mitogen Activated Proteins kinases via a conserved domain. This interaction activates wheat catalase independently of its phosphorylation status but is more promoted by Mn2+, Fe2+ and Ca2+ divalent cations. Interestingly, we have demonstrated that durum wheat catalase activity is differentially regulated by Mitogen Activated Proteins kinases and Calmodulins in the presence of calcium. Moreover, the V0 of the reaction increase gradually following the increasing quantities of Mn2+ divalent cations. Such results have never been described before and suggest i) complex regulatory mechanisms exerted on wheat catalase, ii) divalent cations (Mn2+; Mg2+; Ca2+ and Fe2+) act as key cofactors in these regulatory mechanisms.

A holistic and sustainable approach linked to drought tolerance of Mediterranean crops.

The rapid increase in average temperatures and the progressive reduction in rainfalls caused by climate change is reducing crop yields worldwide, particularly in regions with hot and semi-arid climates such as the Mediterranean area. In natural conditions, plants respond to environmental drought stress with diverse morphological, physiological, and biochemical adaptations in an attempt to escape, avoid, or tolerate drought stress. Among these adaptations to stress, the accumulation of abscisic acid (ABA) is of pivotal importance. Many biotechnological approaches to improve stress tolerance by increasing the exogenous or endogenous content of ABA have proved to be effective. In most cases the resultant drought tolerance is associated with low productivity incompatible with the requirements of modern agriculture. The on-going climate crisis has provoked the search for strategies to increase crop yield under warmer conditions. Several biotechnological strategies, such as the genetic improvement of crops or the generation of transgenic plants for genes involved in drought tolerance, have been attempted with unsatisfactory results suggesting the need for new approaches. Among these, the genetic modification of transcription factors or regulators of signaling cascades provide a promising alternative. To reconcile drought tolerance with crop yield, we propose mutagenesis of genes controlling key signaling components downstream of ABA accumulation in local landraces to modulate responses. We also discuss the advantages of tackling this challenge with a holistic approach involving different knowledge and perspectives, and the problem of distributing the selected lines at subsidized prices to guarantee their use by small family farms.

Enzyme stabilization and thermotolerance function of the intrinsically disordered LEA2 proteins from date palm.

In date palm, the LEA2 genes are of abundance with sixty-two members that are nearly all ubiquitous. However, their functions and interactions with potential target molecules are largely unexplored. In this study, five date palm LEA2 genes, PdLEA2.2, PdLEA2.3, PdLEA2.4, PdLEA2.6, and PdLEA2.7 were cloned, sequenced, and three of them, PdLEA2.2, PdLEA2.3, and PdLEA2.4 were functionally characterized for their effects on the thermostability of two distinct enzymes, lactate dehydrogenase (LDH) and ß-glucosidase (bglG) in vitro. Overall, PdLEA2.3 and PdLEA2.4 were moderately hydrophilic, PdLEA2.7 was slightly hydrophobic, and PdLEA2.2 and PdLEA2.6 were neither. Sequence and structure prediction indicated the presence of a stretch of hydrophobic residues near the N-terminus that could potentially form a transmembrane helix in PdLEA2.2, PdLEA2.4, PdLEA2.6 and PdLEA2.7. In addition to the transmembrane helix, secondary and tertiary structures prediction showed the presence of a disordered region followed by a stacked ß-sheet region in all the PdLEA2 proteins. Moreover, three purified recombinant PdLEA2 proteins were produced in vitro, and their presence in the LDH enzymatic reaction enhanced the activity and reduced the aggregate formation of LDH under the heat stress. In the bglG enzymatic assays, PdLEA2 proteins further displayed their capacity to preserve and stabilize the bglG enzymatic activity.

Catalase Gene Family in Durum Wheat: Genome-Wide Analysis and Expression Profiling in Response to Multiple Abiotic Stress Conditions.

Catalase (CAT) is an antioxidant enzyme expressed by the CAT gene family and exists in almost all aerobic organisms. In fact, the CAT enzyme modulates the hydrogen peroxide (H2O2) contents in cells by translating this toxic compound into water (H2O) and O2- to reduce reactive oxygen species (ROS) contents in cells. ROS are produced as a result of biotic and abiotic environmental stressors. To avoid ROS toxicity, plants are armed with different enzymatic and non-enzymatic systems to decompose ROS. Among the enzymatic system, CAT proteins are well studied. CAT not only controls growth and development in plants but is also involved in plant defense against different stresses. So far, the CAT gene family has not been reported in durum wheat (Triticum turgidum ssp. durum L.). Therefore, a genome-wide comprehensive analysis was conducted to classify the CAT genes in the durum wheat genome. Here, six TdCAT genes were identified. Based on phylogenetics, the TdCAT genes belong to three groups (Groups I-III) which is explainable by their comparable structural characteristics. Using bio-informatic analysis, we found that the secondary and tertiary structures were conserved among plants and present similar structures among durum wheat CATs. Two conserved domains (pfam00199 and pfam06628) are also present in all identified proteins, which have different subcellular localizations: peroxisome and mitochondrion. By analyzing their promoters, different cis-elements were identified, such as hormone-correlated response and stress-related responsive elements. Finally, we studied the expression pattern of two catalase genes belonging to two different sub-classes under different abiotic stresses. Expression profiling revealed that TdCAT2 and TdCAT3 presented a constitutive expression pattern. Moreover, both genes are induced in response to salt, mannitol, cold, heat and ABA. Thus, we speculate that those genes are activated by different stresses, such as oxygen deficiency, light, cold, abscisic acid and methyl jasmonate. Further, this study will help in understanding the behavior of CAT genes during environmental stress in durum wheat and in Triticeae species in general.

Biopreservative Effect of the Tunisian Halophyte Lobularia maritima Flavonoid Fraction, Used Alone and in Combination with Linalool in Stored Minced Beef Meat.

In the present study, Lobularia maritima (Lm) flavonoid extract (LmFV) was characterized by HPLC analyses and five compounds were detected. Further, to describe the chemical content of the matrix, GC-MS analyses after silylation were performed; the obtained results showed the presence of a large number of components belonging to several chemical classes, mostly sugar alcohols, sugars, fatty acids, and terpenes. Firstly, the antibacterial activities of this fraction and linalool (Lin) were evaluated against eight foodborne pathogenic strains with MIC values between 2.3 and 5.8 mg/mL and 0.23 and 0.7 mg/mL, respectively. Then, the antioxidant activity of both was evaluated by the DPPH antiradical test and the phosphomolybdenum test. Furthermore, the biopreservative effect of LmFV alone and in combination with Lin on minced beef stored at 4 °C for 14 days was evaluated using microbiological and physiochemical tests. LmFV at 4.6% alone significantly reduced microbial spoilage in ground meat (p < 0.05). The combination of LmFV (4.6%) and Lin (0.46%) was more effective than LmFV alone in inhibiting bacterial contamination, reducing TBARS values and the risk of bacterial contamination, and reducing the accumulation of Met myoglobin (MetMb). This combination, therefore, extends the shelf life of the product by about 10 days. Based on these microbiological results and physicochemical parameters, it can be stated that the addition of Lin potentiates the flavonoid fraction of L. maritima more strongly against the deterioration of meat quality by significantly improving its biopreservative effect as a natural conservative.

Superoxide dismutase (SOD) family in durum wheat: promising candidates for improving crop resilience.

The SOD family has been extensively analyzed at genome wide level in several crops. However, little is known about this family in durum wheat. In this study, a total of 14 TdSOD genes were identified in whole durum wheat genome including 8 TdCu-ZnSODs, 2 TdMnSODs, and 4 TdFeSODs. In silico analysis evinced that TdSOD family members displayed a closer evolutionary relationship, similar gene structure and protein features with their homologs from other plant species. Furthermore, the analysis of their promoter regions revealed the presence of a great number of cis-regulatory elements related to plant development, abiotic and biotic stresses, phytohormones, and several potential binding sites for transcription factors. Interestingly, 3D structure analysis revealed that TdCu-ZnSOD2A-2 and TdCu-ZnSOD2B-2, belonging to the Cu-Zn group, were modeled as copper chaperone for SOD like their homologs from rice and Arabidopsis. The expression profile of eight TdSOD candidate genes was investigated under salt, drought, cold, and ABA treatments. Notably, TdCu-ZnSOD2A-1, TdFeSOD4A-1, and TdFeSOD7A-1 were significantly up-regulated under all stress treatments. On the other hand, TdCu-ZnSOD7B and TdMnSOD2B were strongly expressed in roots and leaves under cold stress and TdCu-ZnSOD2B-2 was particularly up-regulated in leaves under ABA treatment. Ultimately, these findings provide valuable information for the identification of attractive candidate genes to improve wheat resilience.

The heat-stable protein fraction from Opuntia ficus-indica seeds exhibits an enzyme protective effect against thermal denaturation and an antibacterial activity.

Desiccation tolerance in developing seeds occurs through several mechanisms among which, a common group of proteins named dehydrins has received considerable attention. So far, there is no information dealing with the accumulation of dehydrins in seeds of Opuntia ficus-indica. We have initiated here an extraction protocol based on two critical steps: heat and acid treatments, and the purity of this fraction was analyzed by FTIR spectroscopy. Western blot analysis of the heat-stable protein fraction (HSF) revealed two main bands of approximately 45 and 44 kDa, while three others of ∼40, 32, and 31 kDa were faintly visible, which were recognized by anti-dehydrin antibodies. This fraction exhibited a Cu2+ -dependent resistance to protease treatments. Next, we performed a series of assays to compare the functional properties of the HSF with those of the previously characterized wheat dehydrin (DHN-5). Antibacterial assays revealed that HSF exhibits only moderate antibacterial activities against gram-negative and gram-positive bacteria, with a minimum inhibition concentration ranging from 0.25 to 1 mg/ml. However, in vitro assays revealed that compared to DHN-5, HSF exhibits higher protective activities of the lactate dehydrogenase (LDH) when exposed to heat, freezing, and dehydration stresses. The protective role of HSF seems to be linked to its best ability to minimize protein aggregation.

Immunomodulatory effect of Linalool (Lin) against CCl4 -induced hepatotoxicity and oxidative damage in rats.

The current study explored the hepatoprotective and immunomodulatory effects of Linalool (Lin) against carbon tetrachloride (CCl4 )-induced toxicity in mice. Four study groups (n = 8 each) were used: (1) a negative control group and (2) a toxicity control group (single dose of CCl4 administered on day 14 as 1 mL/kg of CCL4 in 1% olive oil). Intraperitoneally (i.p.)), and two experimental groups where mice were treated with either (3) Lin (25 mg/kg b.w., orally, daily for 15 days) or (4) pretreated with Lin (25 mg/kg b.w., orally, daily for 14 days) and intoxicated with CCl4 (1 mL/kg of CCL4 in 1% olive oil. i.p.) on day 14. The levels of the anti-inflammatory cytokine interleukin 10 (IL-10), the proinflammatory cytokines TNF-α, IL-6, and TGF-1ß, and the histopathology of the liver were assessed. According to our findings, IL-10 concentrations were significantly increased in Lin-treated groups, while other cytokine levels were marked by a considerable decrease in the toxicity model group (CCl4 -treated group). Histopathological examinations of liver tissues showed that the Lin-treated groups had an almost normal structure. The current findings showed that Lin could inhibit CCl4 -induced liver injury in mice, which warrants further investigation of Lin as a potential protective and therapeutic agent against hepatotoxicity.

Genome-Wide Identification and Expression Analysis of Catalase Gene Families in Triticeae.

Aerobic metabolism in plants results in the production of hydrogen peroxide (H2O2), a significant and comparatively stable non-radical reactive oxygen species (ROS). H2O2 is a signaling molecule that regulates particular physiological and biological processes (the cell cycle, photosynthesis, plant growth and development, and plant responses to environmental challenges) at low concentrations. Plants may experience oxidative stress and ultimately die from cell death if excess H2O2 builds up. Triticum dicoccoides, Triticum urartu, and Triticum spelta are different ancient wheat species that present different interesting characteristics, and their importance is becoming more and more clear. In fact, due to their interesting nutritive health, flavor, and nutritional values, as well as their resistance to different parasites, the cultivation of these species is increasingly important. Thus, it is important to understand the mechanisms of plant tolerance to different biotic and abiotic stresses by studying different stress-induced gene families such as catalases (CAT), which are important H2O2-metabolizing enzymes found in plants. Here, we identified seven CAT-encoding genes (TdCATs) in Triticum dicoccoides, four genes in Triticum urartu (TuCATs), and eight genes in Triticum spelta (TsCATs). The accuracy of the newly identified wheat CAT gene members in different wheat genomes is confirmed by the gene structures, phylogenetic relationships, protein domains, and subcellular location analyses discussed in this article. In fact, our analysis showed that the identified genes harbor the following two conserved domains: a catalase domain (pfam00199) and a catalase-related domain (pfam06628). Phylogenetic analyses showed that the identified wheat CAT proteins were present in an analogous form in durum wheat and bread wheat. Moreover, the identified CAT proteins were located essentially in the peroxisome, as revealed by in silico analyses. Interestingly, analyses of CAT promoters in those species revealed the presence of different cis elements related to plant development, maturation, and plant responses to different environmental stresses. According to RT-qPCR, Triticum CAT genes showed distinctive expression designs in the studied organs and in response to different treatments (salt, heat, cold, mannitol, and ABA). This study completed a thorough analysis of the CAT genes in Triticeae, which advances our knowledge of CAT genes and establishes a framework for further functional analyses of the wheat gene family.

A New Approach in Meat Bio-Preservation through the Incorporation of a Heteropolysaccharide Isolated from Lobularia maritima L.

In this study, a new heteropolysaccharide extracted from Lobularia maritima (L.) Desv. (LmPS), a halophyte harvested in Tunisia, was evaluated as an antioxidant and antibacterial additive in the bio-preservation of raw minced meat. For antibacterial testing, Gram-positive bacteria such as Staphylococcus aureus ATCC and Listeria monocytogenes ATCC 19,117 and Gram-negative bacteria such as Salmonella enterica ATCC 43,972 and Escherichia coli ATCC 25,922 were used. The results indicate that this polymer had a significant antibacterial activity against foodborne pathogens. Additionally, the effects of LmPS at 0.15, 0.3 and 0.6% on refrigerated raw ground beef were investigated from a microbiological, chemical, and sensory perspective. Microbiological analysis of the meat showed that treatment with LmPS significantly (p < 0.05) improved its shelf life, while the biochemical analysis evidenced a significant (p < 0.05) decrease in lipid oxidation. LmPS at 0.6% significantly reduced by 61% and 48% metmyoglobin accumulation at the end of the storage period when compared to BHT and control samples, respectively. The chemometric approach highlighted the relationships among the different meat quality parameters. LmPS can be introduced in the food industry as a powerful natural additive and could be an alternative to synthetic antioxidant compounds.

The Life Cycle of the Xylophagous Beetle, Steraspis speciosa (Coleoptera, Buprestidae), Feeding on Acacia Trees in Saudi Arabia.

The xylophagous beetle, Steraspis speciosa, has infected Acacia forests in Saudi Arabia, causing significant damage and even leading to the death of several trees. In the Ha'il region, in the north of Saudi Arabia, an investigation of 13 study sites shows that the Acacia population is mainly composed of three species: A. gerrardii (90.3%), A. ehrenbergiana (7.5%), and A. raddiana (2.2%) and that 21.7% of this population was infected by S. speciosa. The age of the tree (young, adult, old) and environment habitat (Dam, Wadi, Plateau) effects, and insect life-cycle were studied in the protected Machar National Park. Infection in the park, estimated at 25.4%, mainly affects the oldest trees (20.1%) more than the youngest ones (2.3%), while the driest environments (Plateau, 38.8%) are more vulnerable to infection than humid habitats (Dam, 9.4%). The life cycle of S. speciosa lasts about two years, with four stages to complete metamorphosis: mating and eggs (≈3 months), larvae (≈16 months), pupae (≈3 months), and emergency and adults (≈3 months). The larvae stage with many metamorphic instars was the most harmful for tree and takes the longest. The female beetle lays its eggs on weak stem parts. Steraspis speciosa larvae feed on the stems of Acacia trees, and the instar larvae were gathered under the bark of infected stems, harming most of the phloem and a large portion of the xylem. When combined with a prolonged period of drought, S. speciosa causes the withering of numerous branches and, in extreme cases, kills the entire tree.

Enhancing growth and salinity stress tolerance of date palm using Piriformospora indica.

Endophytic fungi are known to enhance plant growth and performance under salt stress. The current study investigated the growth, as well as biochemical and molecular properties of Phoenix dactylifera colonized with the mutualistic fungus Piriformospora indica, under control and salinity stress. Our findings indicated an increase in the plant biomass, lateral root density, and chlorophyll content of P. indica-colonized plants under both normal and salt stress conditions. Furthermore, there was a decline in the inoculated plants leaf and root Na+/K+ ratio. The colonization enhanced the levels of antioxidant enzymes such as catalase, superoxide dismutase, and peroxidase in plants. Increased ionic content of Zn and P were also found in salt-stressed date palm. The fungus colonization was also associated with altered expression levels of essential Na+ and K+ ion channels in roots like HKT1;5 and SOS1 genes. This alteration improved plant growth due to their preservation of Na+ and K+ ions balanced homeostasis under salinity stress. Moreover, it was confirmed that RSA1 and LEA2 genes were highly expressed in salt-stressed and colonized plant roots and leaves, respectively. The current study exploited P. indica as an effective natural salt stress modulator to ameliorate salinity tolerance in plants.

Genetically engineered crops for sustainably enhanced food production systems.

Genetic modification of crops has substantially focused on improving traits for desirable outcomes. It has resulted in the development of crops with enhanced yields, quality, and tolerance to biotic and abiotic stresses. With the advent of introducing favorable traits into crops, biotechnology has created a path for the involvement of genetically modified (GM) crops into sustainable food production systems. Although these plants heralded a new era of crop production, their widespread adoption faces diverse challenges due to concerns about the environment, human health, and moral issues. Mitigating these concerns with scientific investigations is vital. Hence, the purpose of the present review is to discuss the deployment of GM crops and their effects on sustainable food production systems. It provides a comprehensive overview of the cultivation of GM crops and the issues preventing their widespread adoption, with appropriate strategies to overcome them. This review also presents recent tools for genome editing, with a special focus on the CRISPR/Cas9 platform. An outline of the role of crops developed through CRSIPR/Cas9 in achieving sustainable development goals (SDGs) by 2030 is discussed in detail. Some perspectives on the approval of GM crops are also laid out for the new age of sustainability. The advancement in molecular tools through plant genome editing addresses many of the GM crop issues and facilitates their development without incorporating transgenic modifications. It will allow for a higher acceptance rate of GM crops in sustainable agriculture with rapid approval for commercialization. The current genetic modification of crops forecasts to increase productivity and prosperity in sustainable agricultural practices. The right use of GM crops has the potential to offer more benefit than harm, with its ability to alleviate food crises around the world.

Identification and Expression Profiling of Two Saudi Arabia Catalase Genes from Wheat and Barley in Response to Abiotic and Hormonal Stresses.

Catalase is a crucial enzyme in antioxidant defense systems protecting eukaryotes from oxidative stress. These proteins are present in almost all living organisms and play important roles in controlling plant responses to biotic and abiotic stresses by catalyzing the decomposition of H2O2. Despite their importance, little is known about their expression in the majority of monocotyledonous species. Here, we isolated and characterized two novel catalase genes from Triticum turgidum and Hordeum vulgare, designated as TtCAT1 and HvCAT1, respectively. Phylogenetic analysis revealed that TtCAT1 and HvCAT1 presented 492 aa and shared an important identity with other catalase proteins belonging to subfamily 1. Using bioinformatic analysis, we predicted the 3D structure models of TtCAT1 and HvCAT1. Interestingly, analysis showed that the novel catalases harbor a peroxisomal targeting signal (PTS1) located at their C-terminus portion, as shown for other catalase proteins. In addition, this motif is responsible for the in silico peroxisomal localization of both proteins. Finally, RT-qPCR analysis showed that TtCAT1 and HvCAT1 are highly expressed in leaves in normal conditions but faintly in roots. Moreover, both genes are upregulated after the application of different stresses such as salt, osmotic, cold, heavy metal, and hormonal stresses. The positive responses of TtCAT1 and HvCAT1 to the various stimuli suggested that these proteins can help to protect both species against environmental stresses.