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Abstract Background Argonaute (AGO), Dicer-like (DCL), and RNA-dependent RNA polymerase (RDR) are essential components of RNA silencing pathways in plants. These components are crucial for the generation and regulatory functions of small RNAs, especially in plant development and response to environmental stresses. Despite their well-characterized functions in other plant species, there is limited information about these genes and their stress responses in centipedegrass (Eremochloa ophiuroides), a key turfgrass species. Results Using genome-wide analysis we identified 20 AGO, 6 DCL, and 10 RDR members in centipedegrass and provided a comprehensive overview of their characteristics. We performed the chromosomal location, gene duplication, syntenic analysis, conserve motif, gene structure, and cis-acting elements analysis. And conducted phylogenetic analyses to clarify the evolutionary relationships among the EoAGO, EoDCL, and EoRDR gene families. Three-dimensional modeling prediction of EoAGO, EoDCL, and EoRDR proteins supported the phylogenetic classification. Furthermore, we examined the expression patterns of these genes in different tissues (spike, stem, leaf, root, and flower) and under different stress conditions (cold, salt, drought, aluminum, and herbicide) using RT-qPCR. The results revealed that most of EoAGO, EoDCL, and EoRDR genes were upregulated in response to multiple abiotic stresses, while some exhibited unique responses, suggesting potential specialized regulatory functions. Conclusion In this study, we performed a comprehensive genome‑wide identification, and phylogenetic and expression pattern analyses of the EoAGO, EoDCL and EoRDR gene families. Our analysis provides a foundation for future research on the RNA silence elements of turfgrass, and affords scientific basis and insights for clarifying the expression patterns of EoAGO, EoDCL and EoRDR genes under adversity stress. Further functional validation and molecular breeding of these genes can be carried out for enhancing the stress resistance of centipedegrass.

Abstract Background Bamboo is an important nontimber forestry product worldwide, while growth, development and geographic distribution of bamboo are often affected by abiotic stresses. Fatty acid desaturases have important roles in regulating plant abiotic stress tolerance, especially low-temperature. However, there is no report on genome-wide of FAD genes in bamboo under abiotic stresses. Results A toltal of 43 PeFAD genes were identified in moso bamboo genome, which were unevenly located in 17 scaffolds. Phylogenetic analysis indicated that PeFAD genes were divided into 6 groups and ADS/FAD5 group was absence in momo bamboo, and gene structure and histidine-motifs remained highly conserved in each group. The expansion of PeFAD genes was mainly caused by tandem and segmental duplications of SAD/FAB2 group. We also identified 59 types of miRNAs targeting PeFAD genes. RNA-seq data indicated that PeFAD genes were transcribed in various organs/tissues with different degrees, and responded to abiotic stresses and hormone treatments, including cold, salt, drought, SA, ABA, BR, NAA and GA. Co-expression analysis under cold stress showed that PeCBF3 might directly bind the promoter of top cold-responsive PeSLD1 gene that contained LTR cis-element and DRE core element. The qRT-PCR assay also validated the expression pattern of PeSLD1 and its upstream regulatory gene PeCBF3. Conclusion In this study, we performed comprehensive genome-wide survey of PeFAD genes in moso bamboo and analyzed their expression patterns in various tissues and organs, and under abiotic stresses and phytohormones treatment. The qRT-PCR assay validated the cold inducibility of PeSLD1 and PeCBF3. This work showed critical roles of PeFAD genes in abiotic stresses responses. This is the first report on genome-wide analysis of PeFAD genes in moso bamboo, which will provide critical gene resources for molecular breeding of stress-toleranct moso bamboo.

Abstract Melatonin has been found to be crucial in the growth and development of plants under stress conditions. In this study, the effects of melatonin and nano melatonin regarding the growth and development of tomato plants, along with their photosynthetic pigment, phenol, and antioxidant activity, were investigated under saline conditions. The study was conducted using a completely randomized design with three replications, and the applied treatments were salt stress and foliar spraying of melatonin at a concentration of 0 (control), melatonin (Mel), and nano capsule-melatonin (Nano-Mel) at 500 µM. Salinity treatments included application of sodium chloride with two concentration of 0 mM NaCl (S1) and 50 mM NaCl (S2). Under saline conditions, Mel and Nano-Mel increased both shoot and root fresh and dry weights, improved relative water content (RWC), and enhanced antioxidant activity and phenolic content. Salinity elevated leaf ABA content, unaffected by Mel or Nano-Mel. Chlorophyll fluorescence and SPAD values demonstrated resilience to salinity with Mel and Nano-Mel applications. Nano-Mel notably mitigated Na + accumulation in leaves under salinity, helping maintain K + homeostasis. Proline levels rise due to salinity but decreased with Mel and Nano-Mel treatments. Electrolyte leakage (EL) increased under salinity but is significantly reduced by Mel, indicating enhanced membrane stability. The findings reveal that salinity stress significantly reduced plasma membrane intrinsic protein (PIP) expression in roots and leaves, whereas Mel and Nano-Mel treatments enhance PIP expression, particularly in roots. The study concludes that Mel and Nano-Mel effectively alleviate salinity-induced stress, promoting growth and maintaining physiological homeostasis in tomato plants.

Winter oilseed rape (Brassica napus L.), the principal oilseed crop in Europe, is notably vulnerable to spring frosts that can drastically reduce yields in ways that are challenging to predict with standard techniques. Our research focused on evaluating the efficacy of photosynthetic efficiency analysis in this crop and identifying specific chlorophyll fluorescence parameters severely impacted by frost, which could serve as noninvasive biomarkers for yield decline. The experiments were carried out in semi-controlled conditions with several treatments: a control, one day at -3°C, three days at -3°C, one day at -6°C, and three days at -6°C. We employed continuous-excitation and pulse-amplitude-modulation chlorophyll fluorescence measurements to assess plant sensitivity to frost. Also, plant gas exchange and chlorophyll content index measurements were performed. Certain parameters strongly correlated with final yield losses, thereby establishing a basis for developing new agricultural protocols to predict and mitigate frost damage in rapeseed crops accurately.

During their life cycle, plants are always exposed to multiple abiotic stresses that negatively affect their growth and development. Based on this fact, plants developed many mechanisms to reduce or tolerate those stresses. Plants undergo a wide range of morphological, physiological, and biochemical changes in response to environmental stresses. However, drought is one of many other environmental stresses which is considered to be the most significant environmental issues that affect the lives of organisms on the planet of Earth. With the recent increase in the severity of climate change, researchers have devoted their efforts to a deeper understanding of the effects of drought on the level of plant response from a physiological and biochemical standpoint. With the recent increase in the severity of climate changes, the problem of drought has gotten worse, thus researchers have focused their efforts on developing a deeper knowledge of how drought affects plant response at the physiological and biochemical levels. The plant undergoes several significant changes, one of which is an alteration in its hormonal balance. Specific hormones become more effective and assist the plant in sustaining a tolerable level of free radicals, while other hormones become less active under non-growth-promoting environments. Abscisic acid, sometimes referred to as the stress hormone, is one of these plant hormones. Its function under stress is to slow down the plant's growth to keep it at an acceptable level of growth. The hormones ascorbic acid, glycine betaine, alpha-tocopherol, melatonin, and Jasmonic are known to be growth-stimulating substances as well as non-enzymatic antioxidants that help suppress eliminated free radical formation. Focusing on this, this review highlighted the function of several plant hormones and the processes that accompany them in reducing the harm caused to plants by drought stress

Growth of crops in the semi-arid and arid regions of the world is significantly affected by salinity stress. The present study investigated maize, which is a globally cultivated crop and known for its salt sensitivity. Widespread cultivation and notable characteristics of maize make it an exemplary model for investigating stress response. We analyzed maize plants morphological and biochemical responses under salinity stress at different intervals. Current results showed that under 100 mM NaCl stress, germination rate of maize seeds decreases up to 40% compared to their respective control non-stressed seeds. Additionally, prolonged exposure to salinity stress negatively impacted various physiological and biochemical aspects of maize plants including shoot/root length, leaf width, and chlorophyll contents, especially in plants treated with NaCl for 21 days. Furthermore, our findings showed that the NaCl stress triggered various enzymatic and non-enzymatic activities, including catalase (CAT), polyphenol oxidase (PPO), total polyphenol (TPP), and flavonoid in maize plants. However, maize plants respond differently to NaCl stress regarding protein content in different durations. This research underscores the urgent need for innovative strategies to mitigate salinity stress and food security for local maize varieties in saline regions and provides valuable insights to tackle these challenges.

Abstract Insect’s resilience to adverse conditions poses a significant challenge for integrated pest control. This has resulted in huge economic losses to agriculture and forestry production as well as a range of severe ecological issues. As a physiological mechanism of insects, digestive physiology plays an important role in the process of adaptation to stress factors. However, there has been no systematic review of what stresses insects can adapt to through digestive physiology and how digestive physiology is involved in insect adaptation to stresses. In this review, the potential link between digestive physiology and adaptation of insects to biotic and abiotic stresses, including plant defense mechanisms, chemical insecticides, and entomopathogenic microorganisms, is analyzed. We point to that digestive physiology composed of digestive enzymes and gut microbial communities is an important strategy for insects to resist plant physical defense (e.g., hemicellulose, pectin, and microfibers), chemical defense (e.g., azadirachtin, diterpenoid acids, and phenolic glycosides), chemical insecticide stress, and entomopathogenic microorganism infection. In addition, the primary function of the digestive physiology in insects is to ensure energy supply during biotic and abiotic stress, assist in the metabolism of exogenous toxins (e.g., anti-insect proteins, primary metabolites, secondary metabolites, and insecticides), and improve their innate immunity against entomopathogenic microorganisms. This review is helpful to elucidate the mechanism of pest adaptation to adversity, and provide a breakthrough point for analyzing the causes of pest outbreaks. Graphical abstract

Abstract Background Alfalfa (Medicago sativa L.) is the most widely planted legume forage and one of the most economically valuable crops in the world. Serine hydroxymethyltransferase (SHMT), a pyridoxal phosphate-dependent enzyme, plays crucial roles in plant growth, development, and stress responses. To date, there has been no comprehensive bioinformatics investigation conducted on the SHMT genes in M. sativa. Results Here, we systematically analyzed the phylogenetic relationship, expansion pattern, gene structure, cis-acting elements, and expression profile of the MsSHMT family genes. The result showed that a total of 15 SHMT members were identified from the M. sativa genome database. Phylogenetic analysis demonstrated that the MsSHMTs can be divided into 4 subgroups and conserved with other plant homologues. Gene structure analysis found that the exons of MsSHMTs ranges from 3 to 15. Analysis of cis-acting elements found that each of the MsSHMT genes contained different kinds of hormones and stress-related cis-acting elements in their promoter regions. Expression and function analysis revealed that MsSHMTs expressed in all plant tissues. qRT-PCR analysis showed that MsSHMTs induced by ABA, Salt, and drought stresses. Conclusions These results provided definite evidence that MsSHMTs might involve in growth, development and adversity responses in M. sativa, which laid a foundation for future functional studies of MsSHMTs.

Abstract This study aimed to investigate the simultaneous effects of drought and salinity on irrigation management coefficients in maize farms. A three-year field research was conducted in the form of a 3 × 3 factorial experiment with a randomized complete block design and three replications from 2020 to 2022 in a maize farm, in Aliabad Fashafoye, Qom province, Iran. The applied treatments included three levels of salinity (S0 = 1.8, S1 = 5.2, and S2 = 8.6 dS/m) and three levels of irrigation (W0 = 100%, W1 = 75%, and W2 = 50% of field capacity). Evapotranspiration stress coefficient (KS) due to W0S1 and W0S2 treatments was (0.975 and 0.934), (0.974 and 0.932), and (0.962 and 0.935) in 2020, 2021, and 2022, respectively. According to the results, KS decreased by increasing the salinity level of irrigation water, so a 1-unit increase in salinity level above the tolerance threshold of the crop to salinity decreased KS by 0.78 and 1.76% for S1 and S2, respectively. Moreover, each percent of volumetric moisture decrease from field capacity decreased KS by 5.9 and 13.3% in W1 and W2, respectively. Also, with the increase in the intensity of the stresses, the readily available water (RAW) of treatments decreased. The sole application of salinity stress decreased the decreasing slope of RAW by 3.2%, while the application of both stresses resulted in the decreasing slopes of 4.9, 5.7, and 7.8% at the salinity levels of S0, S1, and S2, respectively, compared to the control. The findings of this study show that the accurate estimation of crop evapotranspiration and RAW can help to improve the irrigation schedule, and the amount of irrigation water used is less than in non-stress conditions due to the reduction of total evapotranspiration and less water uptake in environmental stresses in maize farms.

The glutathione peroxidase (GPX) family in plants contains various isoenzymes, each with distinct subcellular localizations, tissue-specific expression patterns, and responses to environmental stress. In current study, we conducted genome-wide bioinformatics analyses of the GPX gene family in Nymphaea colorata, identifying five putative NcGPX genes dispersed across five of the fourteen chromosomes. Examination of the protein sequences revealed that NcGPXs comprehend three conserved cysteine residues, with predicted in-silico subcellular localizations in chloroplast, extracellular, or cytoplasm. We reported that NcGPX genes protein lengths and molecular weight (MW) ranged from 171 to 248 amino acids (aa) and 18.798–27.076 kDa, respectively. A comparative neighbor-joining phylogenetic study revealed that GPX genes were clustered into four main groups (Group A– D) from water lily and two closely related plant species, alongside with Arabidopsis thaliana. The universal analysis showed that segmental duplications occurred within the NcGPX gene family. Investigation of gene structure and motifs suggested that most NcGPX genes have relatively conserved exon-intron structures and motif arrangements. Promoter region exploration of NcGPX genes revealed numerous cis-acting regulatory elements associated with development, stress, and hormone responses. The identified 3D protein structures showed that water lily GPXs form conserved dimeric protein signatures. Finally, gene expression and enzymes accumulation of NcGPXs in response to different abiotic stresses, in leaves of N. colorata were analysed using real-time RT-qPCR and spectrophotometry. The results indicate that different members of the GPX gene family are co-ordinately regulated under specific environmental stress conditions, establishing a foundation for studying their gene functions and improving abiotic stress tolerance in water lily genetic breeding.

In this past decade, the bond between agriculture, food security, and climate change has become increasingly strong. Agriculture is recognized as one of the most endangered systems adversely affected by human activities and environmental issues. In particular, abiotic stress limits the quantity and quality of plant-based food. Heat stress, drought, and salinity impact plants at all different life stages, inducing morphological and physiological changes and provoking a reduction in their nutritional value. Accordingly, low-quality food results in a serious risk for the health of people worldwide. In this scenario, different genetic and biotechnological strategies have been investigated, including the use of New Plant Breeding Techniques (NBTs) and plant cell cultures. In this review, we describe how abiotic stresses alter the property and availability of nutritious food. In addition, we illustrate the advanced techniques that could be employed to address these issues and ameliorate the agricultural practices

Background Living organisms possess the remarkable capacity to swiftly adapt to fluctuations in their environment. In the context of cell signal transduction, a significant challenge lies in ensuring the effective perception of external signals and the execution of appropriate responses. To investigate this phenomenon, a recent study utilized Arabidopsis thaliana as a model plant and induced stress by administering abscisic acid (ABA), a plant hormone, to elucidate the involvement of leucine-rich repeat receptor-like kinase1 (LRR1) in ABA signaling pathways. Methods Homozygous T-DNA insertion alleles for LRR1 and KIN7 were isolated. Quantitative real-time PCR (qRT-PCR) was performed to confirm the expression of the LRR1 gene. Subcellular localization and beta-glucuronidase (GUS) tissue labeling techniques were utilized to determine the expression pattern of the LRR1 gene in cells and tissues. Yeast two-hybrid complementation, bimolecular fluorescence complementation assay, and GST pull-down assays were conducted to validate the interaction of LRR1 proteins. Results Phenotypic analyses revealed that lrr1 and kin7 mutants are less sensitive to the inhibitory effects of ABA on germination and cotyledon greening that is seen in WT. Mutants LRR1 and kinase 7 (KIN7) exhibited resistance to ABA and displayed normal growth patterns under control conditions. The double mutant lrr1kin7 showed reduced responsiveness to ABA. Conversely, overexpression lines LRR1ox2 and LRR1ox10 demonstrated heightened sensitivity to ABA, resulting in severe growth reduction. qRT-PCR assay indicated that exogenous application of ABA led to significant down-regulation of ABI3, ABI4, and ABI5 transcription factors in LRR1 material compared to wild-type WT material. An investigation was conducted to determine the expression pattern and transcriptional level of LRR1 in Arabidopsis. The results revealed ubiquitous expression of LRR1 across all developmental stages and tissue tested. Subcellular localization assays confirmed the presence of LRR1 on the plasma membrane of cells. Furthermore, BiFC assay, yeast two-hybrid complementation, and GST pull-down assays demonstrated an interaction between LRR1 and PYL6 in vitro. These findings provide substantial insights into the involvement of LRR1 in the ABA signaling pathway while regulating seed germination and cotyledon greening during early development in Arabidopsis. This study significantly advances our understanding regarding the correlation between LRR1 and ABA signaling pathways with potential applications for enhancing crop stress resistance.

IntroductionS-adenosylmethionine (SAM), a key molecule in plant biology, plays an essential role in stress response and growth regulation. Despite its importance, the SAM synthetase (SAMS) gene family in sunflowers (Helianthus annuus L.) remains poorly understood.MethodsIn this study, the SAMS genes were identified from the sunflower genome. Subsequently, the protein properties, gene structure, chromosomal location, cis-acting elements, collinearity, and phylogeny of the SAMS gene family were analyzed by bioinformatic methods. Finally, the expression patterns of SAMS genes in different tissues, under different hormonal treatment and abiotic stress were analyzed based on transcriptome data and qRT-PCR.ResultsThis study identified 58 SAMS genes across nine cultivated sunflower species, which were phylogenetically classified into seven distinct subgroups. Physicochemical properties and gene structure analysis showed that the SAMS genes are tightly conserved between cultivars. Collinearity analysis revealed segmental duplications as the primary driver of gene family expansion. The codon usage bias analysis suggested that natural selection substantially shapes the codon usage patterns of sunflower SAMS genes, with a bias for G/C-ending high-frequency codons, particularly encoding glycine, leucine, and arginine. Analysis of the cis-regulatory elements in promoter regions, implied their potential roles in stress responsiveness. Differential expression patterns for HanSAMS genes were observed in different tissues as well as under hormone treatment or abiotic stress conditions by analyzing RNA-seq data from previous studies and qRT-PCR data in our current study. The majority of genes demonstrated a robust response to BRA and IAA treatments in leaf tissues, with no significant expression change observed in roots, suggesting the response of HanSAMS genes to hormones is tissue-specific. Expression analyses under abiotic stresses demonstrated diverse expression profiles of HanSAMS genes, with HanSAMS5 showing significant upregulation in response to both drought and salt stresses.DiscussionThis comprehensive genomic and expression analysis provides valuable insights into the SAMS gene family in sunflowers, laying a robust foundation for future functional studies and applications in crop improvement for stress resilience.

The APETALA2/ethylene-responsive factor (AP2/ERF) transcription factor family is one of the largest transcription factor families in plants. Its subfamily members activate or repress the expression of related genes by specifically binding to cis-acting elements such as the GCC box and DRE/CRT in the promoter regions of downstream interacting genes, and participate in the regulation of biological processes such as growth and development, maturation and senescence, and stress response in fruits and vegetables. In recent years, an increasing number of studies have shown that AP2/ERF can also regulate the quality and resistance of fruits and vegetables by regulating target genes and inducing various phytohormone responses such as ethylene, jasmonic acid and salicylic acid, or by acting as a response factor in response to phytohormone signals. This article provides an overview of the structural characteristics of AP2/ERF transcription factors and their classification and distribution in fruits and vegetables and reviews the latest research progress in the regulatory effect of AP2/ERF on stress resistance in fruits and vegetables through interaction with the major hormone signals. It is our hope that this review will provide a theoretical basis for enhancing stress resistance in fruits and vegetables from the perspective of hormonal regulation of AP2/ERF transcription factors.

Abstract Background Mung bean (Vigna radiata L.) is an important warm-season grain legume. Adaptation to extreme environmental conditions, supported by evolution, makes mung bean a rich gene pool for stress tolerance traits. The exploration of resistance genes will provide important genetic resources and a theoretical basis for strengthening mung bean breeding. B-box (BBX) proteins play a major role in developmental processes and stress responses. However, the identification and analysis of the mung bean BBX gene family are still lacking. Results In this study, 23 VrBBX genes were identified through comprehensive bioinformatics analysis and named based on their physical locations on chromosomes. All the VrBBXs were divided into five groups based on their phylogenetic relationships, the number of B-box they contained and whether there was an additional CONSTANS, CO-like and TOC1 (CCT) domain. Homology and collinearity analysis indicated that the BBX genes in mung bean and other species had undergone a relatively conservative evolution. Gene duplication analysis showed that only chromosomal segmental duplication contributed to the expansion of VrBBX genes and that most of the duplicated gene pairs experienced purifying selection pressure during evolution. Gene structure and motif analysis revealed that VrBBX genes clustered in the same group shared similar structural characteristics. An analysis of cis-acting elements indicated that elements related to stress and hormone responses were prevalent in the promoters of most VrBBXs. The RNA-seq data analysis and qRT-PCR of nine VrBBX genes demonstrated that VrBBX genes may play a role in response to environmental stress. Moreover, VrBBX5, VrBBX10 and VrBBX12 are important candidate genes for plant stress response. Conclusions In this study, we systematically analyzed the genomic characteristics and expression patterns of the BBX gene family under ABA, PEG and NaCl treatments. The results will help us better understand the complexity of the BBX gene family and provide valuable information for future functional characteristics of specific genes in this family.

Introduction Endophytes have symbiosis life within the plant tissues without causing any obvious negative effects. Seaweeds are one of the large and diverse groups of marine plants that play an essential role in marine and oceans ecosystems. Seaweeds show rich diversity of associated microorganisms in compare with the other multicellular organisms. Citrus species, are amongst the most important evergreen fruit trees, cultivated in many countries worldwide. There are several obstacles for citrus production in southern of Iran, limiting continuity of citrus production. Lack of suitable soil, salinity and drought stresses are the main challenges threatening citrus industry in southern of Iran. Similar to other citrus species, the production of Mexican lime is threatened by certain biological stresses (such as pests, plant diseases and weeds) and non-biological stresses (such as salinity, drought, floods, cold and heat stress). Endophytes are advantageous group of microorganisms that protect plants from biotic and abiotic stresses. One of the alternative ways to restore normal plant growth may be to use plant growth to stimulate endophytes. Endophytes can play an important role in plant growth. Endophytes from marine environment are gaining special interest because of their existence in the harsh conditions of marines and ocean ecosystem such as temperature, light availability, high salinity and osmotic stress. Endophytes have already been isolated from various marine habitat, including marine plants, marine invertebrates and vertebrates. Among these organisms, seaweeds are one of the most prevalent sources of marine-derived fungi and bacteria for chemical studies. The purpose of this study was the isolation of associated fungi and bacteria endophytes with seaweed species in Persian Gulf to investigate morphological and molecular characterization by using PCR amplifications ITS1-5.8S-ITS4 regions and 16s rRNA gene respectively. Here, we have evaluated the potential of inoculating Mexican lime seedlings with seaweeds fungi and bacteria endophyte combination, (Aspergillus niger+ Bacillus aquimaris OD14), to improve morphological, biochemical, antioxidant and photosynthesis pigments characterizes of Mexican lime in salinity condition. Materials and Methods The main aim of this study was to investigate the role of endophytic fungi (Aspergillus niger) and bacteria (Bacillus aquimaris OD14) in improving the growth of Mexican lime seedlings. The seaweed samples were collected from coastal regions of Bushehr province and Qeshm Island. Fungi and bacteria endophytes were isolated and identified base on morphological and molecular methods. Molecular characterization was investigated using PCR amplification of ITS1-5.8S-ITS4 regions and 16s rRNA gene respectively. Mexican lime seeds were sterilized with 0.5% sodium hypochlorite for 20 minutes and then completely distilled three times with distilled water. Seedlings pots containing autoclaved soil were placed in the greenhouse of the Faculty of Agriculture, Hormozgan University. The experiment was arranged as a factorial experiment based on randomized complete randomize design with three replications. Isolated fungi and bacteria by MT420720 and MT278260 accession numbers were used in eight months old Mexican lime seedlings. The suspension was adjusted to a concentration of 1×106 cell per ml for fungi and 1×108 cell per ml for bacteria inoculums. For better contact of seedlings with endophytes, inoculation was performed three times. After three months, salinity stress was applied. morphological (Leave, Stem and Root dry and fresh weight), biochemical (Protein, MDA and soluble sugars), antioxidant capacity (CAT, POD, SOD, APX and Gr activity) and photosynthesis pigments (Chlorophyll a, Chlorophyll b, Total Chlorophyll and Carotenoids) characteristics in treated Mexican lime seedlings and control were analyzed. Analysis of variance of traits was performed using SAS software version 9.4 and the means were compared using LSD method with a probability level of P≤0.05. Results and Discussion The results show that most characterizes were significant compare with control. For example, in 6000 µs/cm water salinity, leave fresh weight (203.49%), root fresh weight (347.41%), stem fresh weight (206.81%) and root dry weight (421.95%) were significantly higher compared with control (P>0.001). Endophytes inoculation can significantly improve photosynthesis pigments such as chlorophyll a (65.21%), chlorophyll b (11.9%), total chlorophyll (28.39%) and carotenoids (59.09%) (P>0.001) compare with control. In antioxidant capacity of seedling, CAT, POD, SOD, Gr and APX were analyzed, Endophytes can increase enzymes activity. For biochemical characterizes, in 6000 µs/cm water salinity, endophytes can significantly increase soluble sugars (17.85%) and decrease MDA (35.18%) in inoculated seedlings compare with control (P>0.001). Conclusion The results showed that the use of endophytic fungi and bacteria can increase the growth of Mexican lime seedlings under salinity stress. Thereby it can be used as an effective tool for growing salinity-sensitive plants in saline conditions.

Abstract Background This study explores the impact of various light spectra on the photosynthetic performance of strawberry plants subjected to salinity, alkalinity, and combined salinity/alkalinity stress. We employed supplemental lighting through Light-emitting Diodes (LEDs) with specific wavelengths: monochromatic blue (460 nm), monochromatic red (660 nm), dichromatic blue/red (1:3 ratio), and white/yellow (400–700 nm), all at an intensity of 200 µmol m-2 S-1. Additionally, a control group (ambient light) without LED treatment was included in the study. The tested experimental variants were: optimal growth conditions (control), alkalinity (40 mM NaHCO3), salinity (80 mM NaCl), and a combination of salinity/alkalinity. Results The results revealed a notable decrease in photosynthetic efficiency under both salinity and alkalinity stresses, especially when these stresses were combined, in comparison to the no-stress condition. However, the application of supplemental lighting, particularly with the red and blue/red spectra, mitigated the adverse effects of stress. The imposed stress conditions had a detrimental impact on both gas exchange parameters and photosynthetic efficiency of the plants. In contrast, treatments involving blue, red, and blue/red light exhibited a beneficial effect on photosynthetic efficiency compared to other lighting conditions. Further analysis of JIP-test parameters confirmed that these specific light treatments significantly ameliorated the stress impacts. Conclusions In summary, the utilization of blue, red, and blue/red light spectra has the potential to enhance plant resilience in the face of salinity and alkalinity stresses. This discovery presents a promising strategy for cultivating plants in anticipation of future challenging environmental conditions.

Durum wheat is a crucial staple crop in many arid and semi-arid regions around the world, significantly contributing to local food security. This review paper aims to explore the current status of durum wheat productivity and the potential impacts of future climatic conditions on its cultivation. Various drivers and constraints affecting durum wheat yield are examined, including biotic and abiotic stressors, CO2 concentrations and agronomic practices. Drought and heat stress were identified as the primary yield limiting factors. Furthermore, the influence of climate change on durum wheat is evaluated, focusing on altered precipitation patterns, temperature extremes, and increased atmospheric CO2 levels. Most prominent quantification methods for climate change impact on yields are explored. The paper provides a summary of the current state of research, which reveals some contradictory results for future durum wheat yields. On the one hand, significant increases in productivity due to the fertilization effect of higher CO2 levels are predicted. On the other hand, the crop failures are foreseen as consequence of elevated heat and drought stress as part of climate change. Overall, this paper underlines the importance of understanding the complex interactions between climate change and durum wheat productivity and highlights the urgency to explore sustainable adaptation strategies to ensure future food security.

Pectin is a vital component of plant cell walls and its methylation process is regulated by pectin methylesterase inhibitors (PMEIs). PMEIs regulate the structural and functional modifications of cell walls in plants and play an important role in plant processes such as seed germination, fruit ripening, and stress response. Although the PMEI gene family has been well characterized in model plants, the understanding of its molecular evolution and biological functions in watermelon remains limited. In this study, 60 ClPMEI genes were identified and characterized, revealing their dispersion on multiple chromosomes. Based on a systematic developmental analysis, these genes were classified into three subfamilies, which was further supported by the exon, intron, and conserved motif distribution. Analysis of cis-elements and expression patterns indicated that ClPMEIs might be involved in regulating the tolerance of watermelon to various abiotic stresses. Moreover, distinct ClPMEI genes exhibit specific functions under different abiotic stresses. For example, ClPMEI51 and ClPMEI54 showed a significant upregulation in expression levels during the late stage of drought treatments, whereas ClPMEI3 and ClPMEI12 displayed a significant downregulation under low-temperature induction. Subcellular localization prediction and analysis revealed that the ClPMEI family member proteins were localized to the cell membrane. This study provided an important foundation for the further exploration of the functions of ClPMEI genes in watermelon.

The trihelix transcription factors (THX TFs) play a crucial role in light responses and are involved in plant growth, development, and stress responses. In this study, we have identified 35 trihelix TFs in pearl millet (Pennisetum glaucum), which is one of the most widely grown C4 cereal crops in tropical semi-arid regions. Identified PgTHXs (Trihelix members of P. glaucum) were classified into 5 subgroups (GT1, GT2, GTγ, SH4, and SIP1) based on phylogenetic analysis, and these subgroup members shared similar gene structure and motif distribution pattern. Collinearity analysis exhibited gene duplication events of trihelix family members in pearl millet across the genome. Gene ontology (GO) annotation and cis-regulatory elements (CREs) analysis of PgTHXs suggested their involvement in diverse biological and molecular functions associated with plant growth, development, and stress responses. RNA sequencing data and expression profile displayed differential expression patterns of PgTHXs under abiotic stress and phytohormone treatments. The induced expression pattern of the PgTHX4, PgTHX5, PgTHX24, and PgTHX30 suggested their potential involvement in abiotic stress responses through phytohormonal signalling pathways. Among these, PgTHX24, a GT-3b member, was localized in the nucleus with self-transactivation ability. Overexpression of PgTHX24 positively regulated expression of stress-related markers in transformed pearl millet calli under drought stress conditions. Promoter activity analysis also highlighted the stress-inducible nature of PgTHX24’s promoter. Overall, our findings provide a comprehensive understanding of PgTHXs with a framework for further functional characterization to understand their regulatory role in pearl millet’s growth, development, and stress responses. Key message: Thirty-five trihelix TFs were identified in pearl millet, and a comprehensive expression profile highlighted their functional diversity. Overexpression of PgTHX24 exhibited its potential involvement in abiotic stress responses.

Researchers have recently sought a comprehensive strategy to reduce the harmful effects of synthetic chemicals in agricultural production to improve productivity and quality. Biostimulants benefit plants by protecting soil and water resources and eliminating adverse environmental effects from pesticides and chemical fertilizers. Plant biostimulants, also called bioactivators, are becoming increasingly well-liked in the agricultural sector due to their capacity to boost a plant’s growth rate and increase its resistance to stress. Biostimulants are frequently used because they can increase crop quality, nutrient assimilation, growth rate, and stress tolerance. This article thoroughly examines biostimulants’ effects on ornamental plants, concentrating on their ability to withstand environmental stressors. Prior studies have demonstrated that a combination of non-pathogenic microbes, protein hydrolysates, humic and fulvic acids, and algal extracts benefits ornamental plants. This review’s main aims are biostimulants’ effects on raising agricultural yield, enhancing nutrient uptake, enhancing photosynthesis, and shielding plants from biotic and abiotic stress. The role of biostimulants in more resilient and sustainable farming practices is also covered

[ Objective ] As an important regulator involved in protein synthesis and gene expression , riboso- mal proteins are crucial for plant growth and development and stress response. In this study , a ribosomal protein family gene OsRPL36A was cloned from rice , and a preliminary study was performed for its bio- logical function , providing a basis for the study of OsRPL36A function. [ Methods ] Bioinformatics tech- niques were used to analysis gene structure , cis -regulatory elements , and evolution process of OsRPL36A . Meanwhile , the expression of OsRPL36A in different tissues and under diurnal rhythm , different hor- mones , and abiotic stresses were analyzed by quantitative real-time PCR ( qRT-PCR ) . [ Results ] ( 1 ) OsR- PL36A encoded 98 amino acids with a 297 bp coding region , which belonged to the ribosomal protein L36 supergene family , and was named as OsRPL36A . ( 2 ) The promoter region of OsRPL36A contained 3 rhythmic expression-related elements , 10 light-responsive elements , 14 hormone-responsive elements , and 27 environmental stress response elements. ( 3 ) The expression of OsRPL36A in leaves was relatively higher than that in other tissues and presented a typical rhythmic expression pattern. The expression of OsRPL36A was in- duced by IAA , high temperature , low temperature , osmotic stress , and so on. [ Conclusion ] OsRPL36A was highly expressed in leaves and presented a typical rhythmic expression pattern. OsRPL36A responded to IAA and might be involved in response to heat shock , low temperature , salt , and osmotic stresses.

Abstract Background Plants mediate several defense mechanisms to withstand abiotic stresses. Several gene families respond to stress as well as multiple transcription factors to minimize abiotic stresses without minimizing their effects on performance potential. RNA helicase (RH) is one of the foremost critical gene families that can play an influential role in tolerating abiotic stresses in plants. However, little knowledge is present about this protein family in rapeseed (canola). Here, we performed a comprehensive survey analysis of the RH protein family in rapeseed (Brassica napus L.). Results A total of 133 BnRHs genes have been discovered in this study. By phylogenetic analysis, RHs genes were divided into one main group and a subgroup. Examination of the chromosomal position of the identified genes showed that most of the genes (27%) were located on chromosome 3. All 133 identified sequences contained the main DEXDC domain, the HELICC domain, and a number of sub-domains. The results of biological process studies showed that about 17% of the proteins acted as RHs, 22% as ATP binding, and 14% as mRNA binding. Each part of the conserved motifs, communication network, and three-dimensional structure of the proteins were examined separately. The results showed that the RWC in leaf tissue decreased with higher levels of drought stress and in both root and leaf tissues sodium concentration was increased upon increased levels of salt stress treatments. The proline content were found to be increased in leaf and root with the increased level of stress treatment. Finally, the expression patterns of eight selected RHs genes that have been exposed to drought, salinity, cold, heat and cadmium stresses were investigated by qPCR. The results showed the effect of genes under stress. Examination of gene expression in the Hayola #4815 cultivar showed that all primers except primer #79 had less expression in both leaves and roots than the control level. Conclusions New finding from the study have been presented new insights for better understanding the function and possible mechanism of RH in response to abiotic stress in rapeseed.

Abstract In recent decades, numerous studies have examined the effects of climate change on the responses of plants. These studies have primarily examined the effects of solitary stress on plants, neglecting the simultaneous effects of mixed stress, which are anticipated to transpire frequently as a result of the extreme climatic fluctuations. Therefore, this study investigated the impact of applied chitosan on boosting the resistance responses of peanuts to alkali and mixed drought-alkali stresses. Peanuts were grown in mid-alkaline soil and irrigated with full irrigation water requirements (100%IR), represented alkali condition (100% IR × alkali soil) and stress conditions (70% IR × alkali soil—represented mixed drought-alkali conditions). Additionally, the plants were either untreated or treated with foliar chitosan. The study evaluated various plant physio-chemical characteristics, including element contents (leaves and roots), seed yield, and irrigation water use efficiency (IWUE). Plants that experienced solitary alkali stress were found to be more vulnerable. However, chitosan applications were effective for reducing (soil pH and sodium absorption), alongside promoting examined physio-chemical measurements, yield traits, and IWUE. Importantly, when chitosan was applied under alkali conditions, the accumulations of (phosphorus, calcium, iron, manganese, zinc, and copper) in leaves and roots were maximized. Under mixed drought-alkali stresses, the results revealed a reduction in yield, reaching about 5.1 and 5.8% lower than under (100% IR × alkali), in the first and second seasons, respectively. Interestingly, treated plants under mixed drought-alkali stresses with chitosan recorded highest values of relative water content, proline, yield, IWUE, and nutrient uptake of (nitrogen, potassium, and magnesium) as well as the lowest sodium content in leaves and roots. Enhances the accumulation of (N, K, and Mg) instead of (phosphorus, calcium, iron, manganese, zinc, and copper) was the primary plant response to chitosan applications, which averted severe damage caused by mixed drought-alkali conditions, over time. These findings provide a framework of the nutrient homeostasis changes induced by chitosan under mixed stresses. Based on the findings, it is recommended under mixed drought-alkali conditions to treat plants with chitosan. This approach offers a promising perspective for achieving optimal yield with reduced water usage.

Abstract Background Abiotic stresses in plants include all the environmental conditions that significantly reduce yields, like drought and heat. One of the most significant effects they exert at the cellular level is the accumulation of reactive oxygen species, which cause extensive damage. Plants possess two mechanisms to counter these molecules, i.e. detoxifying enzymes and non-enzymatic antioxidants, which include many classes of specialized metabolites. Sunflower, the fourth global oilseed, is considered moderately drought resistant. Abiotic stress tolerance in this crop has been studied using many approaches, but the control of specialized metabolites in this context remains poorly understood. Here, we performed the first genome-wide association study using abiotic stress-related specialized metabolites as molecular phenotypes in sunflower. After analyzing leaf specialized metabolites of 450 hybrids using liquid chromatography-mass spectrometry, we selected a subset of these compounds based on their association with previously known abiotic stress-related quantitative trait loci. Eventually, we characterized these molecules and their associated genes. Results We putatively annotated 30 compounds which co-localized with abiotic stress-related quantitative trait loci and which were associated to seven most likely candidate genes. A large proportion of these compounds were potential antioxidants, which was in agreement with the role of specialized metabolites in abiotic stresses. The seven associated most likely candidate genes, instead, mainly belonged to cytochromes P450 and glycosyltransferases, two large superfamilies which catalyze greatly diverse reactions and create a wide variety of chemical modifications. This was consistent with the high plasticity of specialized metabolism in plants. Conclusions This is the first characterization of the genetic control of abiotic stress-related specialized metabolites in sunflower. By providing hints concerning the importance of antioxidant molecules in this biological context, and by highlighting some of the potential molecular mechanisms underlying their biosynthesis, it could pave the way for novel applications in breeding. Although further analyses will be required to better understand this topic, studying how antioxidants contribute to the tolerance to abiotic stresses in sunflower appears as a promising area of research.

Abstract The 70 kD heat shock proteins (HSP70s) represent a class of molecular chaperones that are widely distributed in all kingdoms of life, which play important biological roles in plant growth, development, and stress resistance. However, this family has not been systematically characterized in radish (Raphanus sativus L.). In this study, we identified 34 RsHSP70 genes unevenly distributed within nine chromosomes of R. sativus. Phylogenetic and multiple sequence alignment analyses classified the RsHSP70 proteins into six distinct groups (Group A–F). The characteristics of gene structures, motif distributions, and corresponding cellular compartments were more similar in closely linked groups. Duplication analysis revealed that segmental duplication was the major driving force for the expansion of RsHSP70s in radish, particularly in Group C. Synteny analysis identified eight paralogs (Rs-Rs) in the radish genome and 19 orthologs (Rs-At) between radish and Arabidopsis, and 23 orthologs (Rs-Br) between radish and Chinese cabbage. RNA-seq analysis showed that the expression change of some RsHSP70s were related to responses to heat, drought, cadmium, chilling, and salt stresses and Plasmodiophora brassicae infection, and the expression patterns of these RsHSP70s were significantly different among 14 tissues. Furthermore, we targeted a candidate gene, RsHSP70–23, the product of which is localized in the cytoplasm and involved in the responses to certain abiotic stresses and P. brassicae infection. These findings provide a reference for further molecular studies to improve yield and stress tolerance of radish.

PLATZ is a novel zinc finger DNA-binding protein that plays an important role in regulating plant growth and development and resisting abiotic stress. However, there has been very little research on the function of this family gene in tomatoes, which limits its application in germplasm resource improvement. Therefore, the PLATZ gene family was identified and analyzed in tomato, and its roles were predicted and verified to provide a basis for in-depth research on SlPLATZ gene function. In this study, the PLATZ family members of tomato were identified in the whole genome, and 19 SlPLATZ genes were obtained. Functional prediction was conducted based on gene and promoter structure analysis and RNA-seq-based expression pattern analysis. SlPLATZ genes that responded significantly under different abiotic stresses or were significantly differentially expressed among multiple tissues were screened as functional gene resources. SlPLATZ17 was selected for functional verification by experiment-based analysis. The results showed that the downregulation of SlPLATZ17 gene expression reduced the drought and salt tolerance of tomato plants. Tomato plants overexpressing SlPLATZ17 had larger flower sizes and long, thin petals, adjacent petals were not connected at the base, and the stamen circumference was smaller. This study contributes to understanding the functions of the SlPLATZ family in tomato and provides a reference for functional gene screening.

Background Trees have developed a broad spectrum of molecular mechanisms to counteract oxidative stress. Secondary metabolites via phenolic compounds emblematized the hidden bridge among plant kingdom, human health, and oxidative stress. Although studies have demonstrated that abiotic stresses can increase the production of medicinal compounds in plants, research comparing the efficiency of these stresses still needs to be explored. Thus, the present research paper provided an exhaustive comparative metabolomic study in Dalbergia odorifera under salinity (ST) and waterlogging (WL). Results High ST reduced D. odorifera's fresh biomass compared to WL. While WL only slightly affected leaf and vein size, ST had a significant negative impact. ST also caused more significant damage to water status and leaflet anatomy than WL. As a result, WL-treated seedlings exhibited better photosynthesis and an up-regulation of nonenzymatic pathways involved in scavenging reactive oxygen species. The metabolomic and physiological responses of D. odorifera under WL and salinity ST stress revealed an accumulation of secondary metabolites by the less aggressive stress (WL) to counterbalance the oxidative stress. Under WL, more metabolites were more regulated compared to ST. ST significantly altered the metabolite profile in D. odorifera leaflets, indicating its sensitivity to salinity. WL synthesized more metabolites involved in phenylpropanoid, flavone, flavonol, flavonoid, and isoflavonoid pathways than ST. Moreover, the down-regulation of L-phenylalanine correlated with increased p-coumarate, caffeate, and ferulate associated with better cell homeostasis and leaf anatomical indexes under WL. Conclusions From a pharmacological and medicinal perspective, WL improved larger phenolics with therapeutic values compared to ST. Therefore, the data showed evidence of the crucial role of medical tree species’ adaptability on ROS detoxification under environmental stresses that led to a significant accumulation of secondary metabolites with therapeutic value.

The presence of Gibberellic Acid-Stimulated Arabidopsis, GASA, gene family has been reported in many important plants, playing roles in various aspects of plant biology but little has been uncovered in soybeans. Soybean is one of the major plants providing nutrition for humans and livestock globally. In this study, we overexpressed a novel GASA gene (GmGASA1-like) in Glycine max and conducted bioinformatic analyses, evaluated the T2 transgenic line in an open field, and applied major stressors along with the growth promoter GA3 to investigate the potential functions of the GmGASA1-like gene. The results of bioinformatics implied that the GmGASA1-like gene is regulated by GA3, and its protein has the potential to influence key processes of plant growth and development. The transgenic plants (JN74-OE) were significantly taller and had a larger canopy in the field trial at the R1-growth stage and demonstrated superiority in some seed quantity and quality traits after harvesting. Under abiotic stresses (including cold, heat, and drought) and spraying of GA3, the level of GmGASA1-like gene expression in JN74-OE exceeded the levels measured before the treatments. Notably, the highest expression level was observed during the drought stress treatment. Photosynthesis pigments levels in both the overexpressed lines and the control group showed no significant differences. In summary, this study sheds light on the multifaceted roles of the GmGASA1-like gene, impacting soybean plant architecture, seed traits, and stress responses. Ultimately, this research paves the way for a more productive and sustainable soybean industry.

The increase in the frequency and magnitude of environmental stresses poses a significant risk to the stability of food supplies. In coastal areas of the Mediterranean, brackish water has long been considered a limitation on horticultural production. In this scenario, the use of biochar in agriculture could be considered a valuable tool to cope with the deleterious effects of salt stress. This work aimed to investigate, in a protected environment, the effects of different concentrations of biochar (0, 1, and 2% v/v) obtained from poplar (Populus L.) biomass on the yield and quality of dwarf San Marzano ecotype tomatoes irrigated with saline water at different concentrations of NaCl (0, 40 and 80 mM). The increase in salt concentration from 0 to 80 mM NaCl reduced the total yield (−63%) and the number of fruits (−25%), but improved the main quality parameters such as dry matter (+75%), total soluble solids (+56%), and polyphenol content (+43%). Compared to control conditions, biochar supplementation improved the total yield (+23%) and number of fruits (+26%) without altering the functional and organoleptic characteristics of the fruits. The promising results underscore the potential of biochar as a sustainable solution to amend soils in order to improve tomato production under unfavorable conditions such as high salinity. However, there is a need to clarify which adaptation mechanisms triggered by biochar amending improve production responses even and especially under suboptimal growing conditions.

Abiotic and biotic stresses globally constrain plant growth and impede the optimization of crop productivity. The phytohormone auxin is involved in nearly every aspect of plant development. Auxin acts as a chemical messenger that influences gene expression through a short nuclear pathway, mediated by a family of specific DNA-binding transcription factors known as Auxin Response Factors (ARFs). ARFs thus act as effectors of auxin response and translate chemical signals into the regulation of auxin responsive genes. Since the initial discovery of the first ARF in Arabidopsis, advancements in genetics, biochemistry, genomics, and structural biology have facilitated the development of models elucidating ARF action and their contributions to generating specific auxin responses. Yet, significant gaps persist in our understanding of ARF transcription factors despite these endeavors. Unraveling the functional roles of ARFs in regulating stress response, alongside elucidating their genetic and molecular mechanisms, is still in its nascent phase. Here, we review recent research outcomes on ARFs, detailing their involvement in regulating leaf, flower, and root organogenesis and development, as well as stress responses and their corresponding regulatory mechanisms: including gene expression patterns, functional characterization, transcriptional, post-transcriptional and post- translational regulation across diverse stress conditions. Furthermore, we delineate unresolved questions and forthcoming challenges in ARF research.

The NAC (NAM, ATAF and CUC) family is one of the largest transcription factor (TF) families in plant that are involved in the regulatory mechanisms of plant growth and development as well as responses to abiotic stresses. However, the underlying molecular mechanism of drought-responsive NAC family members in soybean still remains inexplicit. In this study, a total of 179 GmNAC genes were identified in the soybean genome. We discovered that the majority of GmNAC members have more than three exons and share a gene and motif structure that is mostly conserved at the N-terminus. Phylogenetic analysis suggested that soybean GmNAC proteins were divided into 10 separate groups. The analysis of cis-elements highlighted the potential role of GmNAC genes in various hormonal and defense related activities. In addition, most of the GmNAC genes showed notable expression in roots and leaves, suggesting their likely role in abiotic stress adaptation. The overexpression of GmNAC3-OE in Arabidopsis increased tolerance to drought stress. Similarly, the GmNAC3-OE plants displayed better survival rates, root length and antioxidant activities. Enhanced expression of stress specific genes in GmNAC3-OE was also recorded. Our findings revealed the potential role of GmNAC3 gene role in regulating soybean response to drought stress and could be used as a potential marker to generate stress resilient plants.

Ascorbate peroxidase (APX) plays a critical role in molecular mechanisms such as plant development and defense against abiotic stresses. As an important economic crop, hemp (Cannabis sativa L.) is vulnerable to adverse environmental conditions, such as drought, cold, salt, and oxidative stress, which lead to a decline in yield and quality. Although APX genes have been characterized in a variety of plants, members of the APX gene family in hemp have not been completely identified. In this study, we (1) identified eight members of the CsAPX gene family in hemp and mapped their locations on the chromosomes using bioinformatics analysis; (2) examined the physicochemical characteristics of the proteins encoded by these CsAPX gene family members; (3) investigated their intraspecific collinearity, gene structure, conserved domains, conserved motifs, and cis-acting elements; (4) constructed a phylogenetic tree and analyzed interspecific collinearity; and (5) ascertained expression differences in leaf tissue subjected to cold, drought, salt, and oxidative stresses using quantitative real-time-PCR (qRT-PCR). Under all four stresses, CsAPX6, CsAPX7, and CsAPX8 consistently exhibited significant upregulation, whereas CsAPX2 displayed notably higher expression levels under drought stress than under the other stresses. Taken together, the results of this study provide basic genomic information on the expression of the APX gene family and pave the way for studying the role of APX genes in abiotic stress.

Abstract Plastid ribosomal proteins play a crucial role in the growth and development of plants, mainly in the gene expression and translation of key genes in chloroplasts. While some information is known about the regulatory processes of plastid ribosomal proteins in various plant species, there is limited knowledge about the underlying mechanisms in rice. In this study, ethyl methanesulfonate (EMS) mutagenesis was used to generate a new mutant called wlp3 (white leaf and panicle3), characterized by white or albino leaves and panicles, which exhibited this phenotype from the second leaf stage until tillering. Furthermore, after a certain period, the newly emerging leaves developed the same phenotype as the rice variety ZH11, while the albino leaves of wlp3 showed an incomplete chloroplast structure and significantly low chlorophyll content. A transition mutation (T to C) at position 380 was identified in the coding region of the LOC_Os03g61260 gene, resulting in the substitution of isoleucine by threonine during translation. WLP3 encodes the ribosomal L18 subunit, which is localized in the chloroplast. Complementation experiments confirmed that LOC_Os03g61260 was responsible for the albino phenotype in rice. WLP3 has high expression in the coleoptile, leaves at the three-leaf stage, and panicles at the heading stage. Compared to the wild-type (WT), wlp3 exhibited reduced chlorophyll synthesis and significantly decreased expression levels of genes associated with plastid development. Yeast two-hybrid (Y2H) analysis revealed that WLP3 interacts with other ribosomal subunits, to influence chloroplast development. These results contribute to a better understanding of the underlying molecular mechanisms of chloroplast development and plastid gene translation.

With the intensification of global climate change and the increasing complexity of agricultural environments, the improvement of rice stress tolerance is an important focus of current breeding research. This review summarizes the current knowledge on the impact of various abiotic stresses on rice and the associated epigenetic responses (DNA methylation). Abiotic stress factors, including high temperature, drought, cold, heavy metal pollution, and high salinity, have a negative impact on crop productivity. Epigenetic changes are key regulatory factors in plant stress responses, and DNA methylation is one of the earliest discovered and thoroughly studied mechanisms in these epigenetic regulatory mechanisms. The normal growth of rice is highly dependent on the environment, and changes in the environment can lead to rice sterility and severe yield loss. Changes in the regulation of the DNA methylation pathway are involved in rice’s response to stress. Various DNA methylation-regulating protein complexes that function during rice development have been identified. Significant changes in DNA methylation occur in numerous stress-responsive genes, particularly those in the abscisic acid signaling pathway. These findings underscore the complex mechanisms of the abiotic stress response in rice. We propose the effective improvement of tolerance traits by regulating the epigenetic status of rice and emphasize the role of DNA methylation in abiotic stress tolerance, thereby addressing global climate change and ensuring food security.

Quinoa (Chenopodium quinoa Willd.) has gained worldwide recognition for its nutritional values, adaptability to diverse environments, and genetic diversity. This review explores the current understanding of quinoa tolerance to environmental stress, focusing on drought, salinity, heat, heavy metals, and UV-B radiation. Although drought and salinity have been extensively studied, other stress factors remain underexplored. The ever-increasing incidence of abiotic stress, exacerbated by unpredictable weather patterns and climate change, underscores the importance of understanding quinoa’s responses to these challenges. Global gene banks safeguard quinoa’s genetic diversity, supporting breeding efforts to develop stress-tolerant varieties. Recent advances in genomics and molecular tools offer promising opportunities to improve stress tolerance and increase the yield potential of quinoa. Transcriptomic studies have shed light on the responses of quinoa to drought and salinity, yet further studies are needed to elucidate its resilience to other abiotic stresses. Quinoa’s ability to thrive on poor soils and limited water resources makes it a sustainable option for land restoration and food security enterprises. In conclusion, quinoa is a versatile and robust crop with the potential to address food security challenges under environmental constraints.

As sessile organisms, plants cannot survive in harmful environments, such as those characterized by drought, flood, heat, cold, nutrient deficiency, and salt or toxic metal stress. These stressors impair plant growth and development, leading to decreased crop productivity. To induce an appropriate response to abiotic stresses, plants must sense the pertinent stressor at an early stage to initiate precise signal transduction. Here, we provide an overview of recent progress in our understanding of the molecular mechanisms underlying plant abiotic stress sensing. Numerous biomolecules have been found to participate in the process of abiotic stress sensing and function as abiotic stress sensors in plants. Based on their molecular structure, these biomolecules can be divided into four groups: Ca2+-permeable channels, receptor-like kinases (RLKs), sphingolipids, and other proteins. This improved knowledge can be used to identify key molecular targets for engineering stress-resilient crops in the field.

Alfin-like (AL) is a small plant-specific gene family characterized by a PHD-finger-like structural domain at the C-terminus and a DUF3594 structural domain at the N-terminus, and these genes play prominent roles in plant development and abiotic stress response. In this study, we conducted genome-wide identification and analyzed the AL protein family in Gossypium hirsutum cv. NDM8 to assess their response to various abiotic stresses for the first time. A total of 26 AL genes were identified in NDM8 and classified into four groups based on a phylogenetic tree. Moreover, cis-acting element analysis revealed that multiple phytohormone response and abiotic stress response elements were highly prevalent in AL gene promoters. Further, we discovered that the GhAL19 gene could negatively regulate drought and salt stresses via physiological and biochemical changes, gene expression, and the VIGS assay. The study found there was a significant increase in POD and SOD activity, as well as a significant change in MDA in VIGS-NaCl and VIGS-PEG plants. Transcriptome analysis demonstrated that the expression levels of the ABA biosynthesis gene (GhNCED1), signaling genes (GhABI1, GhABI2, and GhABI5), responsive genes (GhCOR47, GhRD22, and GhERFs), and the stress-related marker gene GhLEA14 were regulated in VIGS lines under drought and NaCl treatment. In summary, GhAL19 as an AL TF may negatively regulate tolerance to drought and salt by regulating the antioxidant capacity and ABA-mediated pathway.

Abstract Background Glutathione S-transferase (GST) is a crucial enzyme for metabolism, detoxification, and stress resistance in organisms. Many GSTs have been identified in seaweeds, but the isolation and functional analysis of GSTs in Saccharina japonica have not been completed. Result In this study, a total of 32 SjGST genes, localized on 10 scaffolds and 6 contigs, were identified and categorized into three groups. Most of these SjGSTs were presumed to be distributed in the cytoplasm. Tandem duplication had a significant influence on the expansion of the SjGST gene family. Functional analysis of cis-acting elements in the promoter regions demonstrated that SjGSTs enhance the stress resistance of the kelp. Quantitative real-time PCR tests confirmed that SjGSTs positively influence S. japonica sporophytes under stress from low salinity, drought, and high temperature. Recombinant yeast tests further affirmed the role of SjGSTs in stress resistance; SjGSTs improved the growth rate of recombinant yeast under 1.5 M NaCl or 8 mM H2O2. Analysis of biochemical parameters indicated that the optimum temperatures for SjGST20 and SjGST22 were 20 °C, and the optimum pH values were 7.0 and 8.0 for SjGST20 and SjGST22, respectively. The K m values for the substrate 1-chloro-2,4-dinitrobenzene (CDNB) were 2.706 mM and 0.674 mM and were 6.146 mM and 3.559 mM for the substrate glutathione (GSH) for SjGST20 and SjGST22, respectively. Conclusion SjGSTs are important stress resistant genes in S. japonica. This research results will enhance our understanding the function of GSTs in brown seaweeds, and explained its functional roles in stress resistance in marine environments.

Abstract Background Alfalfa (Medicago sativa) is the most widely planted legume forage and one of the most economically valuable crops in the world. The periodic changes in its growth and development and abiotic stress determine its yield and economic benefits. Auxin controls many aspects of alfalfa growth by regulating gene expression, including organ differentiation and stress response. Auxin response factors (ARF) are transcription factors that play an essential role in auxin signal transduction and regulate the expression of auxin-responsive genes. However, the function of ARF transcription factors is unclear in autotetraploid-cultivated alfalfa. Result A total of 81 ARF were identified in the alfalfa genome in this study. Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were analyzed, identifying that ARF genes are mainly involved in transcriptional regulation and plant hormone signal transduction pathways. Phylogenetic analysis showed that MsARF was divided into four clades: I, II, III, and IV, each containing 52, 13, 7, and 9 genes, respectively. The promoter region of the MsARF gene contained stress-related elements, such as ABRE, TC-rich repeats, MBS, LTR. Proteins encoded by 50 ARF genes were localized in the nucleus without guide peptides, signal peptides, or transmembrane structures, indicating that most MsARF genes are not secreted or transported but only function in the nucleus. Protein structure analysis revealed that the secondary and tertiary structures of the 81 MsARF genes varied. Chromosomal localization analysis showed 81 MsARF genes were unevenly distributed on 25 chromosomes, with the highest distribution on chromosome 5. Furthermore, 14 segmental duplications and two sets of tandem repeats were identified. Expression analysis indicated that the MsARF was differentially expressed in different tissues and under various abiotic stressors. The quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis showed that the expression profiles of 23 MsARF genes were specific to abiotic stresses such as drought, salt, high temperature, and low temperature, as well as tissue-specific and closely related to the duration of stress. Conclusion This study identified MsARF in the cultivated alfalfa genome based on the autotetraploid level, which GO, KEGG analysis, phylogenetic analysis, sequence characteristics, and expression pattern analysis further confirmed. Together, these findings provide clues for further investigation of MsARF functional verification and molecular breeding of alfalfa. This study provides a novel approach to systematically identify and characterize ARF transcription factors in autotetraploid cultivated alfalfa, revealing 23 MsARF genes significantly involved in response to various stresses.

Environmental stresses diversely affect multiple processes related to the growth, development, and yield of many crops worldwide. In response, plants have developed numerous sophisticated defense mechanisms at the cellular and subcellular levels to react and adapt to biotic and abiotic stressors. RNA silencing, which is an innate immune mechanism, mediates sequence-specific gene expression regulation in higher eukaryotes. ARGONAUTE (AGO) proteins are essential components of the RNA-induced silencing complex (RISC). They bind to small noncoding RNAs (sRNAs) and target complementary RNAs, causing translational repression or triggering endonucleolytic cleavage pathways. In this review, we aim to illustrate the recently published molecular functions, regulatory mechanisms, and biological roles of AGO family proteins in model plants and cash crops, especially in the defense against diverse biotic and abiotic stresses, which could be helpful in crop improvement and stress tolerance in various plants.

Abstract: The accelerated aging test is widely used to evaluate seed vigor. However, for the wheat crop, discrepancies are found in the literature regarding temperature and period of exposure to stress. This study aimed to evaluate the efficiency of the accelerated aging test in different combinations of time and temperature in seed vigor evaluation in wheat lots and cultivars. The following cultivars were used: Tbio Sintania, Tbio Sossego, Tbio Sinuelo, LG Oro, Tbio Toruk, and CD 150 (Group 1), represented by one lot each, and five lots of the cultivar CD 150 (Group 2). Water content, germination, first count of germination, and seedling emergence in the field were evaluated for characterization of initial physiological potential. Then the accelerated aging test was applied to the lots under the following aging conditions: 41 °C / 48 and 72 h, 43 °C / 40 and 48 h, and 45 °C / 24 and 40 h in plastic boxes, with 40 mL of distilled water and seeds distributed in a single layer on a screen. After aging, the water content and germination of the seeds were determined. Analysis of variance was performed on the data, and the means were compared by Tukey’s test, at 5% probability. The simple correlation test (r) was performed between the analyzed variables and the seedling emergence in the field test. The accelerated aging test with the combinations of 41 °C / 72 h and 43 °C / 48 h is efficient for evaluating seed vigor of wheat lots and cultivars. The combination of 43 °C / 48 h provides results more quickly, saving 24 h in relation to the methodology recommended in the literature (41 °C / 72 h).

The growth of crop plants, particularly spinach (Spinacia oleracea L.), can be significantly impeded by salinity and drought. However, pre-treating spinach plants with traditional biofertilizers like Jeevamrit and Beejamrit (JB) substantially reverses the salinity and drought-induced inhibitory effects. Hence, this study aims to elucidate the underlying mechanisms that govern the efficacy of traditional fertilizers. The present work employed comprehensive biochemical, physiological, and molecular approaches to investigate the processes by which JB alleviates abiotic stress. The JB treatment effectively boosts spinach growth by increasing nutrient uptake and antioxidant enzyme activity, which mitigates the detrimental effects of drought and salinity-induced stress. Under salt and drought stress conditions, the application of JB resulted in an impressive rise in germination percentages of 80 and 60%, respectively. In addition, the application of JB treatment resulted in a 50% decrease in electrolyte leakage and a 75% rise in the relative water content of the spinach plants. Furthermore, the significant reduction in proline and glycine betaine levels in plants treated with JB provides additional evidence of the treatment's ability to prevent cell death caused by environmental stressors. Following JB treatment, the spinach plants exhibited substantially higher total chlorophyll content was also observed. Additionally, using 16S rRNA sequencing, we discovered and characterized five plant-beneficial bacteria from the JB bio-inoculants. These bacterial isolates comprise a number of traits that contribute to growth augmentation in plants. These evidences suggest that the presence of the aforesaid microorganisms (along with additional ones) is accountable for the JB-mediated stimulation of plant growth and development.

Plants being sessile organisms, face environmental challenges and climate change scenarios, that often occur simultaneously (as dual or multifactorial) rather than as a single stress factor. Combined stresses may exert additive impacts on plant growth and yields. The prime challenge to safely feed the burgeoning population, in light of climate change issues, demands precise agriculture systems. Though traditional breeding methods have been utilised but with limited success owing to time, cost, and infrastructure constraints. Modern biotechnological tools, especially the high-throughput omics including genomics, transcriptomics, miRNAomics, metabolomics, lipidomics beside others are being advocated to revolutionize the science of stress biology and to develop stress-smart crops. Omics tools, databases, and pipelines coupled with machine learning, artificial intelligence, and mathematical modeling are proving highly effective not only in deciphering the mechanistic insights of plant stress responses but also in enhancing the stress-tolerance. This review presents current knowledge and updates on recent developments on plant abiotic stress responses and adaptive strategies especially against combined and sequential stresses. Latest developments in omics toolbox and how they are being explored via genetic and genomic engineering, RNA-interference, microRNAs and target mimicry are discussed in detail. Recent success in deployment of biotechnological/omics technologies in modern breeding practices for producing multi-abiotic stress tolerant crops, current challenges and key questions and futuristic trends have also been discussed.

Abstract Citrus plants routinely experience a broad range of biotic and abiotic stress that occur either concurrently or sequentially in the field, causing huge losses in yield. Hence, cultivated citrus plants that tolerate only one type of abiotic stress are insufficient to maintain citrus productivity as the climate changes. Plants primarily develop delicate regulatory mechanisms to detect, transduce and respond to adverse environmental conditions. Therefore, elucidating the physiological, biochemical and molecular mechanisms underlying the dynamic response to multiple abiotic stresses is a prerequisite for determining the targets for genetic improvement programs of citrus. In this review, we pinpoint the current understanding of the physiological basis of citrus tolerance to abiotic stress. Then, we discuss recent insights into the integrated molecular mechanisms that are involved in the citrus response to multiple types of abiotic stress. Finally, we discuss recent prospects for using modern molecular technologies to facilitate the genetic improvement of citrus.