Plant Responses Research Articles

Adaptive significance and origin of flavonoid biosynthesis genes in the grain of cultivated cereals

The majority of cultivated cereals including maize, rice, wheat, barley, oat and rye are consisted of numerous varieties lacking anthocyanin pigmentation or having weak coloration of vegetative organs and/or caryopses. Only rare local races and wild related species have intense coloration of plants and/or grains. The coloration of caryopses is associated with the biosynthesis of colored flavonoids in maternal (pericarp and testa) and hybrid (aleuron) caryopsis tissues. The trait is controlled by dominant alleles of regulatory genes encoding conserved transcription factors of the MYB, bHLH-MYC, and WD40 families forming the MBW protein complex. Recent studies have proven the participation of uncolored and colored flavonoids in the response of plants to biotic and abiotic stresses, and significance of their presence in the whole grain foods has been determined. However, many questions about the adaptive effects and health benefits of anthocyanins remain unanswered. In particular, the reasons why the dominant alleles of regulatory genes controlling pericarp coloration did not become widespread in the course of domestication and breeding of cereals are not clear, although these genes receive special attention in association with health-improving effects of grain nutrition. This article discusses the similarity and specificity of the genetic control of the biosynthesis of flavonoids in the caryopsis in three related cultivated cereals – wheat, barley and rye, and their biological role in the development of the caryopsis and seed germination.

A novel OsGST gene encoding 9glutathione reductase negatively regulates cadmium accumulation in rice

Cadmium (Cd) accumulates in rice and then moves up the food chain, causing serious health problems for humans. Glutathione S-transferase (GST) binds exogenous hazardous compounds to glutathione (GSH), which performs a variety of roles in plant responses to Cd stress. Here, Cd stimulated the transcripts of a novel OsGST gene, and the OsGST protein, which was localized in the nucleus and cytoplasm, was also induced by Cd. In OsGST deletion mutant lines generated by CRISPR/Cas9, more Cd was accumulated, and Cd hypersensitive phenotypes were observed, while transgenic lines overexpressing OsGST exhibited enhanced Cd tolerance and less Cd accumulation. Further analysis indicated that the osgst mutants exhibited considerably greater reactive oxygen species (ROS) and higher GSH level, and the antioxidant activity associated genes’ expression were down-regulated, imply that OsGST controlled rice Cd accumulation and resistance through preserving the equilibrium of the GSH and redox in rice.

N-terminal truncated trehalose-6-phosphate synthase 1 gene (△NIbTPS1) enhances the tolerance of sweet potato to abiotic stress

Sweet potato [Ipomoea batatas (L.) Lam], the crop with the seventh highest annual production globally, is susceptible to various adverse environmental influences, and the study of stress-resistant genes is important for improving its tolerance to abiotic stress. The enzyme trehalose-6-phosphate synthase (TPS) is indispensable in the one pathway for synthesizing trehalose in plants. TPS is known to participate in stress response in plants, but information on TPS in sweet potato is limited. This study produced the N-terminal truncated IbTPS1 gene (△NIbTPS1) overexpression lines of Arabidopsis thaliana and sweet potato. Following salt and mannitol-induced drought treatment, the germination rate, root elongation, and fresh weight of the transgenic A. thaliana were significantly higher than that in the wild type. Overexpression of △NIbTPS1 elevated the photosynthetic efficiency (Fv/Fm) and the activity of superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase in sweet potato during drought and salt treatments, while reducing malondialdehyde and O2∙- contents, although expression of the trehalose-6-phosphate phosphatase gene IbTPP and trehalose concentrations were not affected. Thus, overexpressing the △NIbTPS1 gene can improve the stress tolerance of sweet potato to drought and salt by enhancing the photosynthetic efficiency and antioxidative enzyme system. These results will contribute to understand the functions of the △NIbTPS1 gene and trehalose in the response mechanism of higher plants to abiotic stress.

Deciphering the dual role of persistent luminescence materials: Toxicity and photoreception effects on rice development

Studies on the toxicity of micro- and nanomaterials in plants have primarily focused on their intrinsic effects. However, there is often oversight when considering the potential perceptual responses that plants may exhibit in response to these materials. In this investigation, we assessed the impact of three commercially available persistent luminescence materials (PLMs) that emit red, green, or blue light under various environmental conditions. We subjected rice (Oryza sativa L.), a short-day plant, to nine distinct treatments, including exposure to particles in isolation, their nocturnal afterglow, or a combination of both. We thoroughly examined rice seedling morphology, photosynthesis patterns, metabolite dynamics, and flowering gene expression to determine the biological responses of plants to these particles. These findings demonstrated that PLMs stably interact with rice, and their emitted afterglow precisely matches the perceptual bandwidth of rice photoreceptors. Notably, the nocturnal afterglow from the red and blue PLMs enhanced the vegetative growth of rice seedlings while inhibiting their reproductive development. The blue PLMs exhibited the most pronounced positive effects, while the red PLMs exhibited inhibitory effects. When exposed to a combination of red and blue PLMs, rice displays enhanced growth and development. The observed alterations in the expression patterns of genes responsible for flowering supported these effects. We concluded that PLMs influence rice growth and development due to their inherent properties and intermittent illumination during dark periods. Both factors collectively shape rice growth and development.

Overexpression of a Grape WRKY Transcription Factor VhWRKY44 Improves the Resistance to Cold and Salt of Arabidopsis thaliana.

Plants are often exposed to biotic or abiotic stress, which can seriously impede their growth and development. In recent years, researchers have focused especially on the study of plant responses to biotic and abiotic stress. As one of the most widely planted grapevine rootstocks, 'Beta' has been extensively proven to be highly resistant to stress. However, further research is needed to understand the mechanisms of abiotic stress in 'Beta' rootstocks. In this study, we isolated and cloned a novel WRKY transcription factor, VhWRKY44, from the 'Beta' rootstock. Subcellular localization analysis revealed that VhWRKY44 was a nuclear-localized protein. Tissue-specific expression analysis indicated that VhWRKY44 had higher expression levels in grape roots and mature leaves. Further research demonstrated that the expression level of VhWRKY44 in grape roots and mature leaves was highly induced by salt and cold treatment. Compared with the control, Arabidopsis plants overexpressing VhWRKY44 showed stronger resistance to salt and cold stress. The activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were significantly increased, and the contents of proline, malondialdehyde (MDA) and chlorophyll were changed considerably. In addition, significantly higher levels of stress-related genes were detected in the transgenic lines. The results indicated that VhWRKY44 was an important transcription factor in 'Beta' with excellent salt and cold tolerance, providing a new foundation for abiotic stress research.

Deciphering salt stress responses in Solanum pimpinellifolium through high-throughput phenotyping.

Soil salinity is a major environmental stressor affecting agricultural productivity worldwide. Understanding plant responses to salt stress is crucial for developing resilient crop varieties. Wild relatives of cultivated crops, such as wild tomato, Solanum pimpinellifolium, can serve as a useful resource to further expand the resilience potential of the cultivated germplasm, S. lycopersicum. In this study, we employed high-throughput phenotyping in the greenhouse and field conditions to explore salt stress responses of a S.pimpinellifolium diversity panel. Our study revealed extensive phenotypic variations in response to salt stress, with traits such as transpiration rate, shoot mass, and ion accumulation showing significant correlations with plant performance. We found that while transpiration was a key determinant of plant performance in the greenhouse, shoot mass strongly correlated with yield under field conditions. Conversely, ion accumulation was the least influential factor under greenhouse conditions. Through a Genome Wide Association Study, we identified candidate genes not previously associated with salt stress, highlighting the power of high-throughput phenotyping in uncovering novel aspects of plant stress responses. This study contributes to our understanding of salt stress tolerance in S. pimpinellifolium and lays the groundwork for further investigations into the genetic basis of these traits, ultimately informing breeding efforts for salinity tolerance in tomato and other crops.

Metabolite responses of cucumber on copper toxicity in presence of fullerene C60 derivatives

Copper (Cu) toxicity in crops is a result of excessive release of Cu into environment. Little is known about mitigation of Cu toxicity through the application of carbon-based nanomaterials including water-soluble fullerene C60 derivatives. Two derivatives of fullerene were examined: polyhydroxylated C60 (fullerenol) and arginine C60 derivative. In order to study the response of Cu-stressed plants (Cucumis sativus L.) to these nanomaterials, metabolomics analysis by gas chromatography-mass spectrometry (GC-MS) was performed. Excess Cu (15 μM) caused substantial increase in xylem sap Cu, retarded dry biomass and leaf chlorosis of hydroponically grown cucumber. In Cu-stressed leaves, metabolomes was disturbed towards suppression metabolism of nitrogen (N) compounds and activation metabolism of hexoses. Also, upregulation of some metabolites involving in antioxidant defense system, such as ascorbic acid, tocopherol and ferulic acid, was occurred in Cu-stressed leaves. Hydroponically added fullerene adducts decreased the xylem sap Cu and alleviated Cu toxicity with effectiveness has been most pronounced for arginine C60 derivative. Metabolic responses of plants subjected to high Cu with fullerene derivatives were opposite to that observed under Cu alone. Fatty acids up-regulation (linolenic acid) and antioxidant molecules (tocopherol) down-regulation might indicate that arginine C60 adduct can alleviate Cu induced oxidative stress. Although fullerenol slightly improved cucumber growth, its effect on metabolic state of Cu-stressed plants was not statistically significant. We suggest that tested fullerene C60 adducts have a potential to prevent Cu toxicity in plants through a mechanism associated with their capability to restrict xylem transport of Cu from roots to shoot, and to maintain antioxidative properties of plants.

Integrated analysis of DNA methylome and transcriptome revealing epigenetic regulation of CRIR1-promoted cold tolerance

BackgroundDNA methylation contributes to the epigenetic regulation of nuclear gene expression, and is associated with plant growth, development, and stress responses. Compelling evidence has emerged that long non-coding RNA (lncRNA) regulates DNA methylation. Previous genetic and physiological evidence indicates that lncRNA-CRIR1 plays a positive role in the responses of cassava plants to cold stress. However, it is unclear whether global DNA methylation changes with CRIR1-promoted cold tolerance.ResultsIn this study, a comprehensive comparative analysis of DNA methylation and transcriptome profiles was performed to reveal the gene expression and epigenetic dynamics after CRIR1 overexpression. Compared with the wild-type plants, CRIR1-overexpressing plants present gained DNA methylation in over 37,000 genomic regions and lost DNA methylation in about 16,000 genomic regions, indicating a global decrease in DNA methylation after CRIR1 overexpression. Declining DNA methylation is not correlated with decreased/increased expression of the DNA methylase/demethylase genes, but is associated with increased transcripts of a few transcription factors, chlorophyll metabolism and photosynthesis-related genes, which could contribute to the CRIR1-promoted cold tolerance.ConclusionsIn summary, a first set of transcriptome and epigenome data was integrated in this study to reveal the gene expression and epigenetic dynamics after CRIR1 overexpression, with the identification of several TFs, chlorophyll metabolism and photosynthesis-related genes that may be involved in CRIR1-promoted cold tolerance. Therefore, our study has provided valuable data for the systematic study of molecular insights for plant cold stress response.

Changes in tomato plant anti-herbivore defences after soil application of a biofungicide containing Bacillus subtilis (Serenade ASO)

ABSTRACT Plants have limited resources to allocate to defences against infection and herbivory. While interactions between plant responses to microbial and herbivore attack are complex, it is often the case that the induction of one response will act antagonistically to the other. Recent studies have shown that plant growth promoting rhizobacteria, which improves overall plant health and general stress resistance, can enhance both anti-microbial and anti-herbivore defences. We investigated how soil application of the biofungicide Serenade ASO (Bacillus subtilis strain QST 713), which primes plant defences against fungal and bacterial infection and promotes plant growth, affects anti-herbivore defences by measuring both constitutive and induced defences. We applied Serenade one or two times to the soil of tomato plants and measured the numbers of type IV glandular trichomes on leaves, the weight gain of a generalist caterpillar (beet armyworms; BAW), and the activity of two enzymes associated with defence against insects (polyphenoloxidase and peroxidase). Serenade treated plants grew faster and foliage from treated plants had significantly higher numbers of glandular trichomes and higher polyphenoloxidase and peroxidase activities than untreated plants. However, Serenade treatment did not affect the degree of induction of plant defences when damaged by BAW feeding and did not slow the growth rate of BAW relative to plants not treated with Serenade. Therefore, the biofungicide Serenade increased plant growth and altered the densities of trichomes and the activities of two defensive enzymes in plants, but it did not affect overall susceptibility of the plants to a generalist herbivore.

Passion fruit HD-ZIP genes: Characterization, expression variance, and overexpression PeHB31 enhanced drought tolerance via lignin pathway

The HD-ZIP (homeodomain-leucine zipper) genes hold significant importance in transcriptional regulation, especially in plant development and responses to abiotic stresses. However, a comprehensive study targeting HD-ZIP family members in passion fruit has been absent. In our current research, 34 HD-ZIP family members (PeHBs) were identified by bioinformatics analysis. Transcriptome analysis revealed that PeHBs exhibited distinct expression patterns when subjected to the four different abiotic stresses, and significant differential expression of PeHBs was also found among the three developmental stages of the fruit and between the purple and yellow genotype passion fruit leaves. An integrated metabolome and transcriptome analysis further revealed that the HD-ZIP III class gene PeHB31 (homologous to ATHB8), was co-upexpressed with lignans in yellow fruit P. edulis (commonly used as a resistance rootstock) when compared to purple fruit P. edulis. The transformation of Arabidopsis and yeast with the PeHB31 gene showed an enhancement in their capacity to withstand drought conditions. Notably, the transgenic Arabidopsis plants exhibited an increase in lignin content within the vascular tissues of their stems. This research lays the groundwork for future studies on the control mechanisms of lignin biosynthesis by HD-ZIP genes (especially HD-ZIP classes III and I) involved in drought tolerance.

Influence of Drought Stress on the Rhizosphere Bacterial Community Structure of Cassava (Manihot esculenta Crantz).

Drought presents a significant abiotic stress that threatens crop productivity worldwide. Rhizosphere bacteria play pivotal roles in modulating plant growth and resilience to environmental stresses. Despite this, the extent to which rhizosphere bacteria are instrumental in plant responses to drought, and whether distinct cassava (Manihot esculenta Crantz) varieties harbor specific rhizosphere bacterial assemblages, remains unclear. In this study, we measured the growth and physiological characteristics, as well as the physical and chemical properties of the rhizosphere soil of drought-tolerant (SC124) and drought-sensitive (SC8) cassava varieties under conditions of both well-watered and drought stress. Employing 16S rDNA high-throughput sequencing, we analyzed the composition and dynamics of the rhizosphere bacterial community. Under drought stress, biomass, plant height, stem diameter, quantum efficiency of photosystem II (Fv/Fm), and soluble sugar of cassava decreased for both SC8 and SC124. The two varieties' rhizosphere bacterial communities' overall taxonomic structure was highly similar, but there were slight differences in relative abundance. SC124 mainly relied on Gamma-proteobacteria and Acidobacteriae in response to drought stress, and the abundance of this class was positively correlated with soil acid phosphatase. SC8 mainly relied on Actinobacteria in response to drought stress, and the abundance of this class was positively correlated with soil urease and soil saccharase. Overall, this study confirmed the key role of drought-induced rhizosphere bacteria in improving the adaptation of cassava to drought stress and clarified that this process is significantly related to variety.

The supply of phosphate fertilizers affects the uptake of macronutrients and the productivity of Brachiaria cultivars during the establishment period

Phosphate fertilizer is necessary in Brachiaria species to boost fodder yield and nitrogen uptake. Know Plant response the phosphate guides nutrient dosing for optimal growth. The goal was to assess how phosphorus (P) dose affected forage production and macronutrient uptake in forage plants during the establishment period. The experimental design was in a 9 × 2 factorial scheme. Nine forage plants of the genus Brachiaria were evaluated: B. decumbens cv. Basilisk, B. humidícola cv. BRS Tupi, B. humidícola, B. ruziziensis, B. brizantha cvs. Marandu, BRS Piatã, Xaraés, BRS Paiaguás and hybrid (B. brizantha × B. ruziziensis) cv. BRS Ipyporã, two doses of P: 6 and 72 mg/dm−3 of P. At the lowest dose of P, the most productive forages were Paiaguás and ruziziensis. In contrast, at the highest dose of P, the forages ruziziensis, Basilisk, Piatã, Paiaguás and Xaraés were the most productive. When compared to the use of 6 mg/dm−3 P, dose of 72 mg/dm−3 P generated an increase in forage production of 803%. The greater forage production provided by the higher P content in the soil is reflected in greater uptakes of macronutrients by forages, following the decreasing order of N > K > Mg > Ca > S = P. The highest efficiencies to produce 1 g of dry matter (DM) at doses of 6 and 72 mg/dm−3 of P were observed in the Paiaguás and humidicola, respectively. In soils with more readily available phosphorus, macronutrient conversion into plant material is more effective. As a result, grasses of the genus Brachiaria generate more DM with less mineral content.

Comparative responses of two maize genotypes with contrasting drought tolerance to biochar application

The impact of biochar application on plant performance under drought stress necessitates a comprehensive understanding of biochar–soil interaction, root growth, and plant physiological processes. Therefore, pot experiments were conducted to assess the effects of biochar on plant responses to drought stress at the seedling stage. Two contrasting maize genotypes (drought-sensitive KN5585 vs. -tolerant Mo17) were subjected to biochar application under drought stress conditions. The results indicated that biochar application decreased soil exchangeable Na+ and Ca2+ contents while increased soil exchangeable K+ content (2.7-fold) and electrical conductivity (4.0-fold), resulting in an elevated leaf sap K+ concentration in both maize genotypes. The elevated K+ concentration with biochar application increased root apoplastic pH in the drought-sensitive KN5585, but not in the drought-tolerant Mo17, which stimulated the activation of H+-ATPase and H+ efflux in KN5585 roots. Apoplast alkalinization of the drought-sensitive KN5585 resulting from biochar application further inhibited root growth by 30.7%, contributing to an improvement in water potential, a reduction in levels of O2–, H2O2, T-AOC, SOD, and POD, as well as the down-regulation of genes associated with drought resistance in KN5585 roots. In contrast, biochar application increased leaf sap osmolality and provided osmotic protection for the drought-tolerant Mo17, which was associated with trehalose accumulation in Mo17 roots. Biochar application improved sucrose utilization and circadian rhythm of Mo17 roots, and increased fresh weight under drought stress. This study suggests that biochar application has the potential to enhance plant drought tolerance, which is achieved through the inhibition of root growth in sensitive plants and the enhancement of osmotic protection in tolerant plants, respectively.Graphical

ATBS1-INTERACTING FACTOR 2 Positively Regulates Freezing Tolerance via INDUCER OF CBF EXPRESSION 1/C-REPEAT BINDING FACTOR-Induced Cold Acclimation Pathway.

The INDUCER OF CBF EXPRESSION 1/C-REPEAT BINDING FACTOR (ICE1/CBF) pathway plays a crucial role in plant responses to cold stress, impacting growth and development. Here, we demonstrated that ATBS1-INTERACTING FACTOR 2 (AIF2), a non-DNA-binding basic helix-loop-helix transcription factor, positively regulates freezing tolerance through the ICE1/CBF-induced cold tolerance pathway in Arabidopsis. Cold stress transcriptionally upregulated AIF2 expression and induced AIF2 phosphorylation, thereby stabilizing the AIF2 protein during early stages of cold acclimation. The AIF2 loss-of-function mutant, aif2-1, exhibited heightened sensitivity to freezing before and after cold acclimation. In contrast, ectopic expression of AIF2, but not the C-terminal-deleted AIF2 variant, restored freezing tolerance. AIF2 enhanced ICE1 stability during cold acclimation and promoted the transcriptional expression of CBFs and downstream cold-responsive genes, ultimately enhancing plant tolerance to freezing stress. MITOGEN-ACTIVATED PROTEIN KINASES 3 and 6 (MPK3/6), known negative regulators of freezing tolerance, interacted with and phosphorylated AIF2, subjecting it to protein degradation. Furthermore, transient co-expression of MPK3/6 with AIF2 and ICE1 downregulated AIF2/ICE1-induced transactivation of CBF2 expression. AIF2 interacted preferentially with BIN2 and MPK3/6 during the early and later stages of cold acclimation, respectively, thereby differentially regulating AIF2 activity in a cold acclimation time-dependent manner. Moreover, AIF2 acted additively in a gain-of-function mutant of BRASSINAZOLE-RESISTANT 1 (BZR1; bzr1-1D) and a triple knockout mutant of BRASSINOSTEROID-INSENSITIVE 2 (BIN2) and its homologs (bin2bil1bil2) to induce CBFs-mediated freezing tolerance. This suggests that cold-induced AIF2 coordinates freezing tolerance along with BZR1 and BIN2, key positive and negative components, respectively, of brassinosteroid signaling pathways.

N6-Methyladenosine (m6A) Sequencing Reveals Heterodera glycines-Induced Dynamic Methylation Promoting Soybean Defense.

Unraveling the intricacies of soybean cyst nematode (Heterodera glycines) race 4 resistance and susceptibility in soybean breeding lines-11-452 (highly resistant) and Dongsheng1 (DS1, highly susceptible)-was the focal point of this study. Employing cutting-edge N6-methyladenosine (m6A) and RNA sequencing techniques, we delved into the impact of m6A modification on gene expression and plant defense responses. Through the evaluation of nematode development in both resistant and susceptible roots, a pivotal time point (3 days postinoculation) for m6A methylation sequencing was identified. Our sequencing data exhibited robust statistics, successful soybean genome mapping, and prevalent m6A peak distributions, primarily in the 3' untranslated region and stop codon regions. Analysis of differential methylation peaks and differentially expressed genes revealed distinctive patterns between resistant and susceptible genotypes. In the highly resistant line (11-452), key resistance and defense-associated genes displayed increased expression coupled with inhibited methylation, encompassing crucial players such as R genes, receptor kinases, and transcription factors. Conversely, the highly susceptible DS1 line exhibited heightened expression correlated with decreased methylation in genes linked to susceptibility pathways, including Mildew Locus O-like proteins and regulatory elements affecting defense mechanisms. Genome-wide assessments, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses, and differential methylation peak/differentially expressed gene overlap emphasized the intricate interplay of m6A modifications, alternative splicing, microRNA, and gene regulation in plant defense. Protein-protein interaction networks illuminated defense-pivotal genes, delineating divergent mechanisms in resistant and susceptible responses. This study sheds light on the dynamic correlation between methylation, splicing, and gene expression, providing profound insights into plant responses to nematode infection.

Insights from utilizing data of different quality levels for simulating barley performance under Nordic conditions: APSIM model evaluation

Abstract Crop model-aided ideotyping can accelerate the breeding of resilient barley cultivars. Yet, the accuracy of process descriptions in the crop models still requires substantial improvement, which is only possible with high-quality experimental data. Despite being demanded frequently, such data is still rarely available, especially for Northern European barley production. This study is one of the first to contribute to closing this existing data gap through the targeted collection of high-quality experimental data in pluri-annual, multi-location spring barley field trials in Denmark. With this data the prediction accuracy of APSIM significantly increased in contrast to commonly utilized lower quality datasets. Using this data for model calibration resulted in more accurate predictions of in-season plant development and important state variables (e.g. final grain yield and biomass). The model’s prediction accuracy can ultimately be further improved by examining remaining model weaknesses that were discoverable with the high quality data. Process descriptions regarding, e.g., early and late leaf development, soil water dynamics and respective plant response appeared to require further improvement. By illustrating the effect of data quality on model performance we reinforce the need for more model-guided field experiments.

The UDP-glycosyltransferase gene OsUGT706E2 negatively regulates rice tolerance to blast disease and abiotic stresses

Despite the crucial role of UDP-glycosyltransferases (UGTs) in various stress responses in plants, their biological functions in rice (Oryza sativa L.) remain poorly understood. In this study, we introduce a novel gene, OsUGT706E2, which is expressed at significantly higher levels in wild rice compared to cultivated rice. OsUGT706E2 is active in multiple tissues and localizes to both the nucleus and cytoplasm. Its transcription is notably up-regulated in response to cold stress, blast disease, and several hormone treatments. Overexpression of OsUGT706E2 markedly reduces seedling tolerance to blast disease, cold, and osmotic stress, whereas knocking out OsUGT706E2 enhances seedling tolerance to blast disease and osmotic stress. The expression levels of stress-related genes in OsUGT706E2 overexpressing plants were significantly lower compared to wild-type plants following stress treatment. Conversely, OsUGT706E2 knockout plants exhibited markedly higher expression levels of these genes than the control plants after stress treatment. Metabolome analysis further indicated that OsUGT760E2 influences metabolite content in rice. Specifically, OsUGT760E2-overexpressing seedlings had higher amino acid content and lower lipid content compared to wild-type seedlings, while OsUGT760E2-knockout seedlings showed lower amino acid content and higher lipid content than control seedlings. These findings suggest that OsUGT760E2 negatively regulates resistance to blast disease as well as tolerance to cold and osmotic stress in rice. As a result, OsUGT760E2 represents a promising target for enhancing rice stress tolerance through gene editing approaches.

Volatiles emitted by Pseudomonas aurantiaca ST-TJ4 trigger systemic plant resistance to Verticillium dahliae

Verticillium dahliae is among the most devastating fungal pathogens, causing significant economic harm to agriculture and forestry. To address this problem, researchers have focused on eliciting systemic resistance in host plants through utilizing volatile organic compounds (VOCs) produced by biological control agents. Herein, we meticulously measured the quantity of V. dahliae pathogens in plants via RTqPCR, as well as the levels of defensive enzymes and pathogenesis-related (PR) proteins within plants. Finally, the efficacy of VOCs in controlling Verticillium wilt in cotton was evaluated. Following treatment with Pseudomonas aurantiaca ST-TJ4, the expression of specific VdEF1-α genes in cotton decreased significantly. The incidence and disease indices also decreased following VOC treatment. In cotton, the salicylic acid (SA) signal was strongly activated 24 h posttreatment; then, hydrogen peroxide (H2O2) levels increased at 48 h, and peroxidase (POD) and catalase (CAT) activities increased to varying degrees at different time points. The malondialdehyde (MDA) content and electrolyte leakage in cotton treated with VOCs were lower than those in the control group, and the expression levels of chitinase (CHI) and PR genes (PR10 and PR17), increased at various time points under the ST-TJ4 treatment. The activity of phenylalanine ammonia lyase (PAL) enzymes in cotton treated with VOCs was approximately 1.26 times greater than that in control plants at 24 h，while the contents of phenols and flavonoids increased significantly in the later stage. Additionally, 2-undecanone and 1-nonanol can induce a response in plants that enhances disease resistance. Collectively, these findings strongly suggest that VOCs from ST-TJ4 act as elicitors of plant defence and are valuable natural products for controlling Verticillium wilt.

Opportunity for genome engineering to enhance phosphate homeostasis in crops.

Plants maintain cellular homeostasis of phosphate (Pi) through an integrated response pathway regulated by different families of transcription factors including MYB, WRKY, BHLH, and ZFP. The systemic response to Pi limitation showed the critical role played by inositol pyrophosphate (PP-InsPs) as signaling molecule and SPX (SYG1/PHO81/XPR1) domain proteins as sensor of cellular Pi status. Binding of SPX to PP-InsPs regulates the transcriptional activity of the MYB-CC proteins, phosphate starvation response factors (PHR/PHL) as the central regulator of Pi-deficiency response in plants. Vacuolar phosphate transporter, VPT may sense the cellular Pi status by its SPX domain, and vacuolar sequestration is activated under Pi replete condition and the stored Pi is an important resource to be mobilized under Pi deficiency. Proteomic approaches led to new discoveries of proteins associated with Pi-deficient response pathways and post-translational events that may influence plants in achieving Pi homeostasis. This review provides current understanding on the molecular mechanisms at the transcriptional and translational levels for achieving Pi homeostasis in plants. The potential strategies for employing the CRISPR technology to modify the gene sequences of key regulatory and response proteins for attaining plant Pi homeostasis are discussed.

The impact of irrigation with harvested rainwater containing asbestos cement matrix on the germination characteristics of Solanum lycopersicum

AbstractThe study aims to investigate how the transfer of matrix materials from eroded asbestos cement products induces stress responses in plants. The paper evaluates the exposure and risk factors of plants, water, and soil to asbestos cement materials. Additionally, the experimental results provide empirical evidence for plant stress responses based on physiological and germination parameters. Contamination of irrigation water with asbestos cement raises environmental concerns due to its potential toxicity to plants and soil quality. Asbestos in irrigation water can lead to toxic stress for plants, affecting germination processes and growth. The paper analyzes the effects of preset doses of irrigation water containing asbestos cement matrix on the germination process and physiological parameters of Solanum lycopersicum in a controlled experiment setting. This research proposes methodological developments that could be valuable for environmental plant protection professionals.