Root Stress Research Articles

H2 O2 , NO, and H2 S networks during root development and signalling under physiological and challenging environments: Beneficial or toxic?

Hydrogen peroxide (H2 O2 ) is a reactive oxygen species (ROS) and a key modulator of the development and architecture of the root system under physiological and adverse environmental conditions. Nitric oxide (NO) and hydrogen sulphide (H2 S) also exert myriad functions on plant development and signalling. Accumulating pieces of evidence show that depending upon the dose and mode of applications, NO and H2 S can have synergistic or antagonistic actions in mediating H2 O2 signalling during root development. Thus, H2 O2 -NO-H2 S crosstalk might essentially impart tolerance to elude oxidative stress in roots. Growth and proliferation of root apex involve crucial orchestration of NO and H2 S-mediated ROS signalling which also comprise other components including mitogen-activated protein kinase, cyclins, cyclin-dependent kinases, respiratory burst oxidase homolog (RBOH), and Ca2+ flux. This assessment provides a comprehensive update on the cooperative roles of NO and H2 S in modulating H2 O2 homoeostasis during root development, abiotic stress tolerance, and root-microbe interaction. Furthermore, it also analyses the scopes of some fascinating future investigations associated with strigolactone and karrikins concerning H2 O2 -NO-H2 S crosstalk in plant roots.

Ultrasonic rolling strengthening effect on the bending fatigue behavior of 12Cr2Ni4A steel gears

An innovative method of ultrasonic rolling strengthening is proposed to process the tooth roots of spur cylindrical gears to improve their bending fatigue life. Variations in the residual stress, surface hardness, and depth of the hardened layer of the tooth root were studied. Subsequently, bending fatigue experiments of a single tooth were performed, and relationships linking residual surface stresses, surface hardness, hardened layer depth, and bending fatigue life were determined. The anti-fatigue mechanism of the ultrasonic rolling gear was clarified: it involves the conversion of tensile residual stresses in the gear tooth roots into residual compressive stresses. After ultrasonic rolling treatment, the bending fatigue strength of gears was increased twice, and their fatigue life was extended by 15 times.

Effects of manufacturing errors of gear macro-geometry on gear performance

In gear design, gear performance metrics such as safety factors for tooth root stress and surface durability, peak-to-peak static transmission error (PPSTE), efficiency, mass, and volume are considered. They are calculated by the geometric parameters of gear macro- and micro-geometry, and manufacturing errors related to gear geometry significantly affect gear performance. However, previous studies have only focused on the micro-geometry errors. In this study, Monte Carlo-type robustness analysis was performed considering the manufacturing errors for tooth thickness, tip diameter, and center distance. Gear performance metrics except PPSTE were calculated based on the international standards and geometric characteristics. PPSTE was evaluated analytically due to lack of standards. When the errors were considered, two gear pairs with the safety factors satisfying the design requirements and similar performance for PPSTE, efficiency, mass, and volume showed different gear performances. There were many samples in gear pair 1 that could not satisfy the design requirements of safety factors, and gear pair 2 had the robustness of PPSTE not only at the specific torque but also with wide torque range when compared to gear pair 1. These results imply that considering the gear macro-geometry errors and robustness of PPSTE is significantly important when designing gears.

Sorghum WRKY transcription factor SbWRKY45 enhanced seed germination under drought stress in transgenic Arabidopsis

The WRKY transcription factors (TFs) family is an important family of plant-specific TFs, playing vital roles in various abiotic and biotic stress responses. WRKY TFs are gaining considerable attention due to their significant roles in stress responses. However, their functions in sorghum (Sorghum bicolor) are lagging behind. In this study, a WRKY gene designated as SbWRKY45 was isolated and characterized from sorghum. SbWRKY45, belonging to Group IIa, consists of one intron and two exons and encodes 430 amino acids. SbWRKY45 is located in chromosome 4. The cis-element prediction analysis showed that the promoter region of SbWRKY45 has several abiotic stress-associated elements. The qRT-PCR results showed that SbWRKY45 was significantly up-regulated in response to drought and cold under salt treatments, was notably changed, and was induced weakly under heat stress. SbWRKY45 exhibited a response to stress in different sorghum tissues, including leaves, stems, and roots. A tissue-specific expression pattern showed that SbWRKY45 was highly expressed in roots compared with leaves and stems, suggesting that SbWRKY45 may play an important role in roots. Overexpression of SbWRKY45 increased germination rates and promoted root growth in transgenic Arabidopsis under drought stress. Taken together, our findings indicate that SbWRKY45 may be involved in mediating the response to drought stress and play a vital role in the abiotic stress response of sorghum

Effects of SpsNAC042 transgenic Populus hopeiensis on root development, leaf morphology and stress resistance.

To identify the function of the SpsNAC042 gene and its response to salt and drought stress, the SpsNAC042 gene was transformed into Populus hopeiensis by the Agrobacterium-mediated leaf disc method, and the phenotypic, physiological changes and related genes expression of transgenic lines were analyzed. The results showed that the number and length of roots of transgenic lines increased significantly. The leaves of transgenic lines curled inward. Under salt and simulated drought stress, the transgenic lines showed improved tolerance to salt and drought. The activities of SOD, POD, CAT and proline content in the transgenic lines were significantly increased, and the reduction rates of total chlorophyll and MDA content were significantly decreased, which indicated that the transgenic lines showed strong physiological responses under stress. Meanwhile, the gene expression of MPK6, SOS1, HKT1 and P5CS1 were significantly upregulated, and the gene expression of PRODH1 was significantly downregulated, which preliminarily verified the stress regulation mechanism that SpsNAC042 might activate. The above results showed that the SpsNAC042 gene could promote root development, make leaf morphology curl, and enhance P. hopeiensis tolerance to stress.

Geometry optimisation of highly crowned gear couplings working in high misalignment applications to reduce tooth root stresses

Crowned gear couplings are mechanical components used to transmit power between misaligned rotating shafts. Their geometry is characterised by a significant longitudinal crowning to accommodate angular misalignment. Recent studies reveal that high misalignments drastically reduce the number of teeth in contact and lead to an uneven load distribution among engaged teeth. Consequently, tooth root fracture becomes a common failure mode. Current standards only address misalignment angles below 1.5°, treating applications with greater misalignments as special cases without design guidelines or stress prediction methods. This study proposes a procedure to optimize the design of crowned gear couplings working in high misalignment applications by determining tooth root stress distribution. The geometry is analytically generated, while finite element models are used to calculate the stress distribution. Experimental validation is performed using a dedicated test rig. The obtained results are very close to the ones from the numerical model, demonstrating the suitability of the method for crowned gear couplings operating under significant angular misalignments. The optimized design reduces tooth root stress by 50%, which will increase the fatigue life of the component or enable the application of higher torque values.

Effect of Tooth Profile Modification on Tooth Root Stress of Spur Gear Pump

Effect of Tooth Profile Modification on Tooth Root Stress of Spur Gear Pump

TaLBD1, a LOB transcription factor gene in T. aestivum, confers plant adaptation to low-N stress via modulating N acquisition-associated processes

Distinct members of transcription factor (TF) families act as the critical mediators in plant low-N stress response by regulating transcription of the stress defensive-associated genes. In this study, TaLBD1, a member of the Lateral Organ Boundary (LOB) TF family in Triticum aestivum, was characterized for its role in modulating the plant adaptation to N deprivation condition. TaLBD1 protein harbors the conserved domains that are shared by the plant LOB TF proteins and targets onto nucleus after endoplasmic reticulum (ER) assortment. The transcripts of TaLBD1 were found to be responsive to N starvation stress in both roots and leaves, as shown by their significantly upregulated transcripts during a 27 h regime of N starvation treatment. The tobacco lines with overexpression of TaLBD1 indicated that it can confer to plants an improved phenotype, root system architecture (RSA), biomass, and N accumulation under N starvation treatment. The expression levels of NtRNT2.4 and NtPIN6, two genes encoding nitrate transporter (NRT) and PIN-FORMED proteins in N. tabacum, were found to be significantly upregulated in expression in the N-deprived transgenic lines overexpressing TaLBD1. Knockdown expression on NtRNT2.4 and NtPIN6 led to plants for an alleviation on the N accumulation and RSA establishment relative to WT, suggesting that they are involved in the regulation of plant and RSA formation, respectively. Transcriptome analyses revealed a number of up- and down- regulated genes in the N-pdeprived transgenic lines with TaLBD1 overexpression, which are involved in biological processes associated with signal transduction, transcription, protein biosynthesis, primary or secondary metabolism, and stress defensiveness. Our results together suggested that TaLBD1 positively regulates plant N starvation tolerance through improvement of N uptake and RSA formation. It is valuable in efforts for molecular engineering the high N use efficiency (NUE) cultivars of cereal crops. The member of the LOB transcription factor family TaLBD1 in T. aestivum confers plant tolerance to N starvation stress via modulating N uptake and RSA establishment.

24-epibrassinolide improves cadmium tolerance and lateral root growth associated with regulating endogenous auxin and ethylene in Kentucky bluegrass

The application of phytohormones is a viable technique to increase the efficiency of phytoremediation in heavy metal-contaminated soils. The objective of this study was to determine how the application of 24-epibrassinolide (EBR), a brassinosteroid analog, could regulate root growth and tolerance to cadmium (Cd) stress in Kentucky bluegrass. As a result, the number of lateral root primordia and total root length in the Cd-treated seedlings decreased by 33.1 % and 56.5 %, respectively. After the application of EBR, Cd accumulation in roots and leaves, and the negative effect of Cd on root growth were reduced under Cd stress. Additionally, the expression of the brassinosteroid signaling gene PpBRI1 was significantly upregulated by exogenous EBR. Moreover, exogenous EBR upregulated the expression of genes encoding antioxidant enzymes and improved the activity of antioxidant enzymes, thereby reduced oxidative stress in roots. Finally, targeted hormonomics analysis highlighted the utility of the application of EBR to alleviate the effect of Cd on the reduction in auxin (IAA) content and the increase in ethylene (ACC) content. These were known to be associated with the upregulation in the expression of auxin biosynthesis gene PpYUCCA1 and downregulation in the expression of ethylene biosynthesis gene PpACO1 in the roots treated with Cd stress. Overall, the application of EBR alleviated Cd-induced oxidative stress in addition to improving root elongation and lateral root growth crosstalk with auxin and ethylene in Kentucky bluegrass subjected to Cd stress. This study further highlights the potential role of brassinosteroids in improving the efficiency of phytoremediation for Cd-contaminated soils.

Seismic failure risk analysis of ± 800 kV coupling filter circuit considering material strength deviation

To analyze the seismic failure risk of an 800 kV filter circuit, which is a coupling system consisting of a series of interconnected post electrical equipment and a suspension filter in an ultra-high voltage converter station, dynamic calculations were performed using a 3D finite element model. Using three different probabilistic approaches based on equipment fragility curves generated by fitting log-normal distributions, the seismic fragility of the coupling filter circuit was calculated. Furthermore, the seismic failure risk of the circuit was evaluated utilizing the seismic hazard function of the site and the circuit fragility function. As a significant factor, the impact of material strength deviation on seismic fragility and failure risk was then investigated. The analytical results highlight three essential seismic responses: the root stress of post insulators, disconnect switches, and the axial stress of top suspension insulators. For equipment, post insulators always exhibit the highest vulnerability in the circuit. Compared to the approach employing the fragility definition, the equipment probability deduction approach estimates exorbitant circuit fragility while the maximum probability method slightly underrates it. A safe region exists on the failure risk surface, where the circuit failure risk is near 0. In particular PGA ranges, material strength deviation can remarkably increase the seismic fragility and failure risk of the coupling filter circuit. Consequently, it is recommended to regulate material strength deviation during the design phase to seismically protect the coupling circuit.

Research on root appearance and fatigue life of steel catenary riser (SCR) using GMAW/GTAW-P double-sided root welding process

A steel catenary riser (SCR) is a flexible stand-up pipe that connects a subsea wellhead in the seabed (normally at a depth of more than 1500 m) to a floating platform. Waves, ocean currents, and winds apply substantial loads to SCRs that produce fatigue damage. Hence, the requirements for the appearance of SCR weld joints, particularly the weld root, are extremely strict. This paper proposes a new gas metal arc welding/pulse gas tungsten arc welding (GMAW/GTAW-P) double-sided root welding process for SCRs to obtain a nearly smooth root geometry. Test results show that the average values of root reinforcement, root transition angle, and transition radius achieved with this root welding process are only 169 μm, 6.4°, and 4055 μm, respectively. These values are dramatically lower than those achievable with the best technologies available, such as the surface tension transfer (STT) root welding process and cold metal transfer (CMT) root welding process. The fatigue strength of the double-sided welding joints is improved by at least 45.8% because the root stress concentration is significantly reduced. However, incomplete penetration defects were found when the molten pool position was not appropriate. Solutions for this problem are discussed. The proposed process is believed to be a potential strategy for welding high fatigue life SCRs.

MicroRNA4359b positively regulates the soybean response to salt stress by targeting the F-box protein GmFBX193

MicroRNAs (miRNAs) have important functions in the plant salt stress response. However, the functions of nonconserved miRNAs in soybean salt stress adaptation remain unclear. In this study, the soybean nonconserved miRNA gma-miR4359b and its target mRNA F-box gene GmFBX193 were functionally identified in response to salt stress. gma-miR4359b responded to salt stress in soybean hairy roots, stems, and leaves. Under salt stress, the root length ratio, root surface area ratio, root volume ratio, root tip number, survival rate, chlorophyll content, soluble sugar content, proline content, superoxide dismutase activity, and peroxidase enzyme activity of soybean hairy roots overexpressing gma-miR4359b (MIR4359b) were increased compared to those of the K599 (control) soybean hairy roots, while the relative electrolyte leakage and malondialdehyde content of the MIR4359b soybean hairy roots decreased. In contrast, soybean hairy roots in which target mimicry (MIM4359b) and short tandem target mimic (STTM4359b) inhibited gma-miR4359b exhibited a salt-sensitive phenotype. The transcription level of GmFBX193 was decreased in MIR4359b soybean hairy roots, while the transcription level of GmFBX193 was increased in MIM4359b and STTM4359b soybean hairy roots. GmFBX193 responded to salt stress in soybean roots, and GmFBX193 was identified as a nuclear-localized protein. Under salt stress, soybean hairy roots overexpressing GmFBX193 had a similar phenotype to MIM4359b and STTM4359b soybean hairy roots. Compared with K599 (control) soybean hairy roots, MIR4359b soybean hairy roots had 172 differentially expressed genes (DEGs), and MIM4359b soybean hairy roots had 2129 DEGs. Some known stress-related transcription factors were included among the DEGs. Taken together, these results suggest that gma-miR4359b plays a positive role in the soybean salt stress response by negatively regulating GmFBX193.

Suppression of microRNA168 enhances salt tolerance in rice (Oryza sativa L.)

BackgroundRice is a salt-sensitive crop. Complex gene regulatory cascades are likely involved in salinity stress in rice roots. microRNA168 (miR168) is a conserved miRNA among different plant species. It in-directly regulates the expression of all miRNAs by targeting gene ARGONAUTE1(AGO1). Short Tandem Target Mimic (STTM) technology is an ideal approach to study miRNA functions by in-activating mature miRNA in plants.ResultsIn this study, rice miR168 was inactivated by STTM. The T3 generation seedlings of STTM168 exhibited significantly enhanced salt resistance. Direct target genes of rice miR168 were obtained by in silico prediction and further confirmed by degradome-sequencing. PINHEAD (OsAGO1), which was previously suggested to be a plant abiotic stress response regulator. RNA-Seq was performed in root samples of 150mM salt-treated STTM168 and control seedlings. Among these screened 481 differentially expressed genes within STTM168 and the control, 44 abiotic stress response related genes showed significant difference, including four known salt-responsive genes.ConclusionBased on sequencing and qRT-PCR, a “miR168-AGO1-downstream” gene regulation model was proposed to be responsible for rice salt stress response. The present study proved miR168-AGO1 cascade to play important role in rice salinity stress responding, as well as to be applied in agronomic improvement in further.

Single-base resolution methylome of different ecotype from Pyrus betulaefolia reveals epigenomic changes in response to salt stress

• Drawing the cytosine methylation map across the whole genome of Pyrus betulaefolia roots. • The changes of methylomes in two ecotypes after salt exposed dependent on their salt tolerance abilities. • DNA demethylation induced higher expression levels of some Ca 2+ sensor genes in P. betulaefolia roots. • The higher K + /Na + ratio in the roots of salt-tolerance ecotype is relationship with Ca 2+ sensor genes transcription causing by hypomethylation. The root is the first organ to feel salt stress in woody fruit trees. Understanding the potential epigenetic mechanism induced by salt stress in roots of Pyrus betulaefolia is important for pear breeding using diverse genetic resources. With the help of whole-genome bisulfite sequencing, cytosine methylation was mapped at single-base resolution across the whole genome of P. betulaefolia roots. The P. betulaefolia root genome revealed nearly 11.40%, 39.93%, 22.73%, and 4.17% methylation across all sequenced C sites and in the CG, CHG, and CHH sequence contexts, respectively. Then, the changes in the methylome of the roots relating to salt stress were comparatively analysed in two ecotypes with different salt-stress tolerances. After a global methylome and transcriptome combined analysis, gene body methylation demonstrated an obvious negative correlation with transcription levels, whereas promoter-methylated genes presented lower expression levels than promoter-unmethylated genes. Furthermore, the methylation profiles of Ca 2+ sensor genes in roots of P. betulaefolia . were described, and some were demethylated under salt-stress conditions. In detail, the up-regulation of Ca 2+ sensors and their downstream genes, PbCDPK20.1, PbCDPK20.2, PbAKT1 , and PbHAK25 , resulted from salt-induced promoter methylation changes . Finally, K + accumulation was promoted, and a higher K + /Na + ratio was maintained in roots under salt-stress compared with normal conditions. Additionally, the application of the DNA methylation inhibitor 5-azacytidine in vitro induced DNA demethylation and promoted K + enrichment, whereas the accelerator methyl trifluoromethanesulfonate produced the opposite effects. In conclusion, our result revealed the relationship of DNA methylation and gene expression in P. betulaefolia during salt stress, which will increase our understanding of the epigenetic mechanisms of woody trees.

Physiological and molecular responses of roots differ from those of leaves in spinach plants subjected to short-term drought stress

• Physiological and molecular responses of roots differ from those of leaves in spinach plants subjected to short-term drought stress. • Short-term drought stress triggers oxidative stress in roots but not in leaves. • Dehydrin and PLDα1 polypeptides with different molecular weights accumulate in roots and leaves. • Drought tolerance of roots and leaves might be associated with expression profiles of Dehydrin and PLDα1 polypeptides in these tissues. In this study, physiological responses as well as changes in expressions of specific proteins (dehydrin [DHN] and phospholipase Dα1 [PLDα1]) were determined in leaf and root tissues of Spinacia oleracea L.cv. Matador plants under different levels of drought stress. Spinach plants grown in the plant growth chamber were exposed to two levels of drought stress (Moderate Stress [MS]: 50% Field Capacity [FC] and Severe Stress [SS]: 25% FC) and compared with no stress conditions (Control: 100% [FC]) for a period of 10 days. Results revealed that the roots and leaves of spinach plants responded differently to drought stress, probably due to different antioxidant activities and accumulation of specific proteins (DHN and PLDα1). Moderate or severe drought stress did not alter the oxidation parameters in leaves of S. oleracea L. cv. Matador plants while significant changes associated with oxidative stress were observed in roots. Dehydrin polypeptides (75 and 50 kDa for leaves and 75 kDa for roots) and PLDα1 polypeptides (22 kDa in leaves; 52 kDa and 28 kDa in roots) have been observed to accumulate following drought exposure. The accumulation of these polypeptides was associated with physiological responses of spinach plants which provide evidence for their contribution to the acclimation process in early drought stress. These data suggest that tissues of spinach plant respond differently against different levels of drought stress and that the response is associated with altered expressions of DHN and PLDα1 polypeptides.

Integration of Transcriptome and Metabolome Analyses Reveals the Mechanistic Basis for Cadmium Accumulation in Maize.

Cadmium (Cd) pollution in soil has become a major environmental issue worldwide. However, the underlying molecular mechanism of low grain-Cd accumulation (GCA) in maize is still largely unknown. Herein, we report the mechanistic basis for low GCA in maize by a multiomics approach. The low GCA genotype L63 showed normal vacuolar formation and a lower capacity of xylem loading of Cd than the high-accumulator L42 under Cd stress. Transcriptomic sequencing identified 84 low-GCA-associated genes which are mainly involved in the S-adenosylmethionine (SAM) cycle, metal transport, and vacuolar sequestration. A metabolome analysis revealed that L63 plants had a more active SAM cycle and a greater capacity for terpenoid synthesis and phenylalanine metabolism than L42. Combining the analysis of transcriptome and metabolome characterized several genes as key genes involved in the determination of Cd accumulation. Our study identifies a mechanistic basis for low Cd accumulation in maize grains and provides candidate genes for genetic improvement of crops.

Mechanism of [CO2] Enrichment Alleviated Drought Stress in the Roots of Cucumber Seedlings Revealed via Proteomic and Biochemical Analysis

Cucumber is one of the most widely cultivated greenhouse vegetables, and its quality and yield are threatened by drought stress. Studies have shown that carbon dioxide concentration ([CO2]) enrichment can alleviate drought stress in cucumber seedlings; however the mechanism of this [CO2] enrichment effect on root drought stress is not clear. In this study, the effects of different drought stresses (simulated with 0, 5% and 10% PEG 6000, i.e., no, moderate, and severe drought stress) and [CO2] (400 μmol·mol-1 and 800 ± 40 μmol·mol-1) on the cucumber seedling root proteome were analyzed using the tandem mass tag (TMT) quantitative proteomics method. The results showed that after [CO2] enrichment, 346 differentially accumulating proteins (DAPs) were found only under moderate drought stress, 27 DAPs only under severe drought stress, and 34 DAPs under both moderate and severe drought stress. [CO2] enrichment promoted energy metabolism, amino acid metabolism, and secondary metabolism, induced the expression of proteins related to root cell wall and cytoskeleton metabolism, effectively maintained the balance of protein processing and degradation, and enhanced the cell wall regulation ability. However, the extent to which [CO2] enrichment alleviated drought stress in cucumber seedling roots was limited under severe drought stress, which may be due to excessive damage to the seedlings.

H2S Enhanced the Tolerance of Malus hupehensis to Alkaline Salt Stress through the Expression of Genes Related to Sulfur-Containing Compounds and the Cell Wall in Roots.

Malus is an economically important plant that is widely cultivated worldwide, but it often encounters saline-alkali stress. The composition of saline-alkali land is a variety of salt and alkali mixed with the formation of alkaline salt. Hydrogen sulfide (H2S) has been reported to have positive effects on plant responses to abiotic stresses. Our previous study showed that H2S pretreatment alleviated the damage caused by alkaline salt stress to Malus hupehensis Rehd. var. pingyiensis Jiang (Pingyi Tiancha, PYTC) roots by regulating Na+/K+ homeostasis and oxidative stress. In this study, transcriptome analysis was used to investigate the overall mechanism through which H2S alleviates alkaline salt stress in PYTC roots. Simultaneously, differentially expressed genes (DEGs) were explored. Transcriptional profiling of the Control-H2S, Control-AS, Control-H2S + AS, and AS-H2S + AS comparison groups identified 1618, 18,652, 16,575, and 4314 DEGs, respectively. Further analysis revealed that H2S could alleviate alkaline salt stress by increasing the energy maintenance capacity and cell wall integrity of M. hupehensis roots and by enhancing the capacity for reactive oxygen species (ROS) metabolism because more upregulated genes involved in ROS metabolism and sulfur-containing compounds were identified in M. hupehensis roots after H2S pretreatment. qRT-PCR analysis of H2S-induced and alkaline salt-response genes showed that these genes were consistent with the RNA-seq analysis results, which indicated that H2S alleviation of alkaline salt stress involves the genes of the cell wall and sulfur-containing compounds in PYTC roots.

Transcriptomic and splicing changes underlying tomato responses to combined water and nutrient stress.

Tomato is a horticultural crop of high economic and nutritional value. Suboptimal environmental conditions, such as limited water and nutrient availability, cause severe yield reductions. Thus, selection of genotypes requiring lower inputs is a goal for the tomato breeding sector. We screened 10 tomato varieties exposed to water deficit, low nitrate or a combination of both. Biometric, physiological and molecular analyses revealed different stress responses among genotypes, identifying T270 as severely affected, and T250 as tolerant to the stresses applied. Investigation of transcriptome changes caused by combined stress in roots and leaves of these two genotypes yielded a low number of differentially expressed genes (DEGs) in T250 compared to T270, suggesting that T250 tailors changes in gene expression to efficiently respond to combined stress. By contrast, the susceptible tomato activated approximately one thousand and two thousand genes in leaves and roots respectively, indicating a more generalized stress response in this genotype. In particular, developmental and stress-related genes were differentially expressed, such as hormone responsive factors and transcription factors. Analysis of differential alternative splicing (DAS) events showed that combined stress greatly affects the splicing landscape in both genotypes, highlighting the important role of AS in stress response mechanisms. In particular, several stress and growth-related genes as well as transcription and splicing factors were differentially spliced in both tissues. Taken together, these results reveal important insights into the transcriptional and post-transcriptional mechanisms regulating tomato adaptation to growth under reduced water and nitrogen inputs.

The ā-stem genitive singular in Old Prussian

Root stress in the Old Prussian ā-stem gen. sg. ālg-as was taken from the homonymous o-stem gen. sg. deiw-as (Lith. lángo, Sl. *vȏrna). This analogy took place after the reshuffling of the Balto-Slavic o-stem gen. sg. *-ā as *-ās in the prehistory of Old Prussian. The shortening *-ās > -as was most probably conditioned by the fact that this ending was always unstressed.