Differences In Stress Tolerance Research Articles

Bioinformatics Studies and Examining the Tissue Distribution of Glutathione Reductase and Glucose-6-Phosphate Dehydrogenase Genes to Investigate Gender Differences in Differences in Stress Tolerance in Zebrafish (Danio rerio)

Bioinformatics Studies and Examining the Tissue Distribution of Glutathione Reductase and Glucose-6-Phosphate Dehydrogenase Genes to Investigate Gender Differences in Differences in Stress Tolerance in Zebrafish (Danio rerio)

Weak evidence of trade-offs modulated by seed mass among a guild of closely related winter annuals

Plant-plant interactions are integral to the establishment and persistence of diversity in plant communities. For annual plant species that depend on seeds to regenerate, seed characteristics that confer fitness advantages may mediate processes such as plant-plant interactions. Seed mass is known to vary widely and has been shown to associate with species’ differences in stress tolerance and competitive effects. However, understanding of how seed mass influences species’ responses to competition is less well understood. Using natural assemblages of six closely related annual plant species in Western Australia, we implemented a thinning study to assess how seed mass influences the outcomes of plant-plant interactions. We found relatively weak evidence for competition or facilitation among species. Our strongest results indicated that heavy-seeded species had lower survivorship than light-seeded species when interacting with heterospecifics. Seed mass was also negatively related to overall survival, counter to expectations. These findings indicate some evidence for trade-offs mediated by seed mass in this system. However, we acknowledge that other factors may have influenced our results, such as the use of natural assemblages (rather than using sowing experiments) and the presence of important small-scale environmental variation not captured with our choice of abiotic variables. Further research is required to clarify the role of seed mass in this diverse annual system, ideally including many focal species, and using sowing experiments.

Patience and its relationship to Stress Tolerance in the medical system in Bethlehem Governorate during the Corona pandemic

IntroductionThe COVID-19 pandemic has set unprecedented demand on the medical system globally. Palestine was one of the Arab countries affectedObjectivesThe present study aims to identify the relationship between patience and Stress Tolerance in the medical system in Bethlehem Governorate during the Corona pandemic, as well as to identify the impact of several demographic variables on it.MethodsDescriptive method were used. Appropriate statistical analyses were conducted using (SPSS). A random sample of 160 workers of the medical staff completed the Patience Scale and Coping Processes Scale questionnaire.Results: showed there is a significant positive effect for patience on stress tolerance and there were statistically significant differences in the level of patience in favor of males and single workers. It was also found that there is no difference in the specific duties of a health care worker and no variance of statistical evidence was found in the level of patience due to work with Covid patients but there were differences in stress tolerance in favor of those who do not work with Covid patients.There is a significance in the level of stress tolerance in favor of the National Center in regard to bearing pressure.There was a negative correlation with statistical significance between stress tolerance and age. The nature of stress changes with age, from episodic to chronic, which in turn affects appraisal and coping processesConclusionsThis study, which was conducted on a sample of Palestinian medical workers in the Bethlehem area, showed that at the beginning of the pandemic, the medical system in Palestine was not ready to handle Covid 19, and had no precautions to prevent the disease. In spite of that, the doctors and nurses who were undergoing psychological pressure were able to stand at the front line and face the outbreak of the Corona virus.Disclosure of InterestNone Declared

Patience and its relationship to stress tolerance in relation to demographic factors of the medical system in Bethlehem Governorate during the COVID-19 pandemic.

The present study aims to identify the relationship between patience and stress tolerance in the medical system in Bethlehem Governorate during the COVID-19 pandemic, as well as to identify the impact of several demographic variables on it. A random sample of 160 members/workers of the medical staff completed the Patience Scale and Coping Processes Scale questionnaire. It showed there is a significant positive effect for patience on stress tolerance and there were statistically significant differences in the level of patience in favor of males and single workers. It was also found that there is no difference in the specific duties of a health care worker and no variance of statistical evidence was found in the level of patience due to work with COVID patients but there were differences in stress tolerance in favor of those who do not work with COVID patients. It was also found that there is a significance in the level of stress tolerance in favor of the National Center in regard to bearing pressure. The study findings indicate there was a negative correlation with statistical significance between stress tolerance and age. The nature of stress changes with age, from episodic to chronic, which in turn affects appraisal and coping processes. This study, which was conducted on a sample of Palestinian medical workers in the Bethlehem area, showed that at the beginning of the pandemic, the medical system in Palestine was not ready to handle COVID-19, and had no precautions to prevent the disease. In spite of that, the doctors and nurses who were undergoing psychological pressure were able to stand at the front line and face the outbreak of the coronavirus.

Inhibition of mitochondrial respiration has fundamentally different effects on proliferation, cell survival and stress response in immature versus differentiated cardiomyocyte cell lines.

Myocardial tissue homeostasis is critically important for heart development, growth and function throughout the life course. The loss of cardiomyocytes under pathological conditions ultimately leads to cardiovascular disease due to the limited regenerative capacity of the postnatal mammalian heart. Inhibition of electron transport along the mitochondrial respiratory chain causes cellular stress characterized by ATP depletion as well as excessive generation of reactive oxygen species. Adult cardiomyocytes are highly susceptible to mitochondrial dysfunction whereas embryonic cardiomyocytes in the mouse heart have been shown to be resistant towards mitochondrial complex III inhibition. To functionally characterize the molecular mechanisms mediating this stress tolerance, we used H9c2 cells as an in vitro model for immature cardiomyoblasts and treated them with various inhibitors of mitochondrial respiration. The complex I inhibitor rotenone rapidly induced cell cycle arrest and apoptosis whereas the complex III inhibitor antimycin A (AMA) had no effect on proliferation and only mildly increased cell death. HL-1 cells, a differentiated and contractile cardiomyocyte cell line from mouse atrium, were highly susceptible to AMA treatment evident by cell cycle arrest and death. AMA induced various stress response mechanisms in H9c2 cells, such as the mitochondrial unfolded protein response (UPRmt), integrated stress response (ISR), heat shock response (HSR) and antioxidative defense. Inhibition of the UPR, ISR and HSR by siRNA mediated knock down of key components does not impair growth of H9c2 cells upon AMA treatment. In contrast, knock down of NRF2, an important transcriptional regulator of genes involved in detoxification of reactive oxygen species, reduces growth of H9c2 cells upon AMA treatment. Various approaches to activate cell protective mechanisms and alleviate oxidative stress in HL-1 cells failed to rescue them from AMA induced growth arrest and death. In summary, these data show that the site of electron transport interruption along the mitochondrial respiratory chain determines cell fate in immature cardiomyoblasts. The study furthermore points to fundamental differences in stress tolerance and cell survival between immature and differentiated cardiomyocytes which may underlie the growth plasticity of embryonic cardiomyocytes during heart development but also highlight the obstacles of cardioprotective therapies in the adult heart.

Divergence in the ABA gene regulatory network underlies differential growth control.

The phytohormone abscisic acid (ABA) is a central regulator of acclimation to environmental stress; however, its contribution to differences in stress tolerance between species is unclear. To establish a comparative framework for understanding how stress hormone signalling pathways diverge across species, we studied the growth response of four Brassicaceae species to ABA treatment and generated transcriptomic and DNA affinity purification and sequencing datasets to construct a cross-species gene regulatory network (GRN) for ABA. Comparison of genes bound directly by ABA-responsive element binding factors suggests that cis-factors are most important for determining the target loci represented in the ABA GRN of a particular species. Using this GRN, we reveal how rewiring of growth hormone subnetworks contributes to stark differences in the response to ABA in the extremophyte Schrenkiella parvula. Our study provides a model for understanding how divergence in gene regulation can lead to species-specific physiological outcomes in response to hormonal cues.

Frequency-Dependent Hybridization Contributes to Habitat Segregation in Monkeyflowers.

AbstractSpatial segregation of closely related species is usually attributed to differences in stress tolerance and competitive ability. For both animals and plants, reproductive interactions between close relatives can impose a fitness cost that is more detrimental to the rarer species. Frequency-dependent mating interactions may thus prevent the establishment of immigrants within heterospecific populations, maintaining spatial segregation of species. Despite strong spatial segregation in natural populations, two sympatric California monkeyflowers (Mimulus nudatus and M. guttatus) survive and reproduce in the other's habitat when transplanted reciprocally. We hypothesized that a frequency-dependent mating disadvantage maintains spatial segregation of these monkeyflowers during natural immigration. To evaluate this hypothesis, we performed two field experiments. First, we experimentally added immigrants in varying numbers to sites dominated by heterospecifics. Second, we reciprocally transplanted arrays of varying resident and immigrant frequencies. Immigrant seed viability decreased with conspecific rarity for M. guttatus but not for M. nudatus. We observed immigrant minority disadvantage for both species, but it was driven by different factors-frequency-dependent hybridization for M. guttatus and competition for resources and/or pollinators for M. nudatus. Overall, our results suggest a major role for reproductive interference in spatial segregation that should be evaluated along with stress tolerance and competitive ability.

Lignin biosynthesis and accumulation in response to abiotic stresses in woody plants

Woody plants have to experience various abiotic stresses due to their immobility and perennial characteristics. However, woody plants have evolved a series of specific regulation pathways in physiological and molecular mechanisms to deal with adverse environments. Compared with herbaceous plants, perennial woody plants have the advantages of developed roots and hard stems, and increased secondary xylem, which can strengthen the vascular system of the plants. The lignification process involves the lignin deposition on the cell wall by oxidation and polymerization of lignin monomer, which plays an important role in abiotic stress tolerance. This review focuses on recent progress in the biosynthesis, content, and accumulation of lignin in response to various abiotic stresses in plants. The role of transcription factors is also discussed in regulating lignin biosynthesis to enhance abiotic stress tolerance <italic>via</italic> changing cell wall lignification. Although woody plants shared similar lignin biosynthesis mechanisms with herbaceous plants, the temporal and spatial expression and stress response profiles of lignin biosynthetic genes provide the basis for the differences in stress tolerance of various species. An in-depth understanding of the role of lignin in the abiotic stress tolerance of woody plants will lay the foundation for the next step in tree resistance breeding through genetic engineering.

Multiple analysis of root exudates and microbiome in rice (Oryza sativa) under low P conditions.

Plants release various metabolites from roots and root exudates contribute to differences in stress tolerance among plant species. Plant and soil microbes have complex interactions that are affected by biotic and abiotic factors. The purpose of this study was to examine the differences in metabolites in root exudates of rice (Oryza sativa) cultivars and their correlation with bacterial populations in the rhizosphere. Two rice cultivars (O. sativa cv. Akamai and O. sativa cv. Koshihikari) were grown in soils fertilized with 0g P kg-1 (-P) or 4.8g P kg-1 (+ P). Root exudates and root-attached soil were collected at 13 and 20days after transplanting (DAT) and their metabolites and bacterial community structure were determined. The exudation of proline, serine, threonine, valine and 4-coumarate were increased under low P conditions in both cultivars. There was a positive correlation between the concentration of pantothenate in root exudates and the representation of members of the genera Clostridium and Sporosarcina, which were negatively correlated with root dry weight. Gracilibacter, Opitutus, Pelotomaculum, Phenylobacterium and Oxobacter were positively correlated with root dry weight and presence of allantoin, 2-aminobtyrate and GlcNac. This study provides new information about the response of plants and rhizosphere soil bacteria to low P conditions.

Eight generations of native seed cultivation reduces plant fitness relative to the wild progenitor population.

Native seed for restoration is in high demand, but widespread habitat degradation will likely prevent enough seed from being sustainably harvested from wild populations to meet this need. While propagation of native species has emerged in recent decades to address this resource gap, few studies have tested whether the processes of sampling from wild populations, followed by generations of farm cultivation, reduce plant fitness tolerance to stress over time. To test this, we grew the eighth generation of farm‐propagated Clarkia pulchella Pursh (Onagraceae) alongside seeds from two of the three original wild source populations that established the native seed farm. To detect differences in stress tolerance, half of plants were subjected to a low‐water treatment in the greenhouse. At the outset, farmed seeds were 4.1% heavier and had 4% greater germination compared to wild‐collected seed. At maturity, farmed plants were 22% taller and had 20% larger stigmatic surfaces, even after accounting for differences in initial seed size. Importantly, the mortality of farmed plants was extremely high (75%), especially in the low‐water treatment (80%). Moreover, farmed plants under the high‐water treatment had 90% lower relative fitness than wild plants due to the 1.3 times greater weekly mortality and a 3‐fold reduction in flowering likelihood. Together, these data suggest that bottlenecks during initial sampling and/or unconscious selection during propagation severely reduced genetic diversity and promoted inbreeding. This may undermine restoration success, especially under stressful conditions. These results indicate that more data must be collected on the effects of cultivation to determine whether it is a suitable source of restoration seed.

Effects of ABA and NaCl on physiological responses in selected bryophyte species

The effects of NaCl and abscisic acid (ABA) on selected bryophyte species were studied. Two phylogenetically unrelated halophyte mosses, namely, Entosthodon hungaricus (Boros) Loeske and Hennediella heimii (Hedw.) R.H. Zander in addition to one model non-halophyte moss, Physcomitrella patens (Hedw.) Bruch &amp; Schimp, were selected to compare the variability in certain biochemical and physiological parameters under salt-stress alone and salt-stress upon ABA pretreatment. The results showed different patterns of effects from ABA in all three of the studied species, as well as no common response to salt stress. In general, all of the tested species reacted to exogenous ABA, which definitely contributed to changes observed in morphological development under salt stress, and to the functioning of the salt-tolerance mechanisms. Physcomitrella patens proved to be a salt-tolerant species. Although it is not ecologically classified as a halophyte, these results highlighted that various stress-resistance pathways are supported by similar reactions to different stresses. Significant differences in stress tolerance were documented between the two bryo-halophytes tested by comparing biochemical and physiological parameters. Our findings suggest that different salt-stress-tolerance strategies characterize these two species, both enhanced by exogenous ABA.

Chromosome doubling mediates superior drought tolerance in Lycium ruthenicum via abscisic acid signaling

Plants are continuously affected by unfavorable external stimuli, which influences their productivity and growth. Differences in gene composition and expression patterns lead homologous polyploid plants to exhibit different physiological phenomena, among which enhanced environmental adaptability is a powerful phenotype conferred by polyploidization. The mechanisms underlying the differences in stress tolerance between diploids and autotetraploids at the molecular level remain unclear. In this research, a full-length transcription profile obtained via the single-molecule real-time (SMRT) sequencing of high-quality single RNA molecules for use as background was combined with next-generation transcriptome and proteome technologies to probe the variation in the molecular mechanisms of autotetraploids. Tetraploids exhibited an increase in ABA content of 78.4% under natural conditions and a superior stress-resistance phenotype under severe drought stress compared with diploids. The substantial differences in the transcriptome profiles observed between diploids and autotetraploids under normal growth conditions were mainly related to ABA biosynthesis and signal transduction pathways, and 9-cis-epoxycarotenoid dioxygenase 1 (NCED1) and NCED2, which encode key synthetic enzymes, were significantly upregulated. The increased expression of the ABRE-binding factor 5-like (ABF5-like) gene was a pivotal factor in promoting the activation of the ABA signaling pathway and downstream target genes. In addition, ABA strongly induced the expression of osmotic proteins to increase the stress tolerance of the plants at the translational level. We consider the intrinsic mechanisms by which ABA affects drought resistance in tetraploids and diploids to understand the physiological and molecular mechanisms that enhance abiotic stress tolerance in polyploid plants.

N6-Methyladenine DNA Methylation in Japonica and Indica Rice Genomes and Its Association with Gene Expression, Plant Development, and Stress Responses

N6-Methyladenine (6mA) DNA methylation has recently been implicated as a potential new epigenetic marker in eukaryotes, including the dicot model Arabidopsis thaliana. However, the conservation and divergence of 6mA distribution patterns and functions in plants remain elusive. Here we report high-quality 6mA methylomes at single-nucleotide resolution in rice based on substantially improved genome sequences of two rice cultivars, Nipponbare (Nip; Japonica) and 93-11 (Indica). Analysis of 6mA genomic distribution and its association with transcription suggest that 6mA distribution and function is rather conserved between rice and Arabidopsis. We found that 6mA levels are positively correlated with the expression of key stress-related genes, which may be responsible for the difference in stress tolerance between Nip and 93-11. Moreover, we showed that mutations in DDM1 cause defects in plant growth and decreased 6mA level. Our results reveal that 6mA is a conserved DNA modification that is positively associated with gene expression and contributes to key agronomic traits in plants.

Effect of Polyethylene Glycol Induced Water Stress on Germination and Seedling Growth of Wheat (&lt;i&gt;Triticum aestivum&lt;/i&gt;)

The performance of twenty wheat genotypes under Polyethylene Glycol (PEG) induced water stress during germination and early seedling growth stages were tested under three levels of water potential i) Control (Tap water), ii) -2 bars and iii) -4 bar at the Crop Physiology and Ecology Laboratory of Hajee Mohammad Danesh Science and Technology University, Dinajpur during September 2014 to October 2014. Rate of germination and vigor index of all wheat genotypes were delayed with the increment of water stress induced by PEG. Shoot and root lengths and seedling dry weight of 10 days old seedlings were found to be reduced due to the increment of water stress. However, the degree of reduction of these parameters with the increment of water stress was not similar for all wheat genotypes. Stress tolerance index (STI) based on seedling dry weight indicated a wide difference in stress tolerance among the wheat genotypes. At moderate water deficit stress, BARI Gom 25, E 34, E 28 and BAW 1170 showed more stress tolerance and the wheat genotypes- Sourav, E 23 and BAW 1140 showed greater stress sensitivity than the other wheat genotypes. At higher water deficit stress, BARI Gom 25, BARI Gom 28, E 28 and BAW 1170 showed more stress tolerance and the wheat genotypes- Satabdi, Sourav, BARI Gom 26, E 23, E 38, E 24, BAW 1163, BAW 1140 and BAW 1151 showed greater stress sensitivity than the others. Considering both moderate and high water deficit stress, BARI Gom 25, E 28 and BAW 1170 were found as tolerant and Sourav, E 23 and BAW 1140 were found as water deficit stress sensitive wheat genotypes. The Agriculturists 2017; 15(1) 81-91

Sirtuins regulate proteomic responses near thermal tolerance limits in the blue mussels Mytilus galloprovincialis and Mytilus trossulus.

The blue mussels Mytilus galloprovincialis and M. trossulus are competing species with biogeographical ranges set in part by environmental exposure to heat and hyposalinity. The underlying cellular mechanisms influencing interspecific differences in stress tolerance are unknown, but are believed to be under regulation by sirtuins, nicotinamide adenine dinucleotide (NAD+)-dependent deacylases that play a critical role in the cellular stress response. A comparison of the proteomic responses of M. galloprovincialis and M. trossulus to an acute heat shock in the presence and absence of the sirtuin inhibitor suramin (SIRT1, 2 and 5) showed that sirtuins affected molecular chaperones, oxidative stress proteins, metabolic enzymes, cytoskeletal and signaling proteins more in the heat-sensitive M. trossulus than in the heat-tolerant M. galloprovincialis Interactions between sirtuin inhibition and changes in the abundance of proteins of β-oxidation and oxidative stress in M. trossulus suggest a greater role of sirtuins in shifting metabolism to reduce the production of reactive oxygen species near thermal limits. Furthermore, RNA-binding proteins initiating and inhibiting translation were affected by suramin in M. galloprovincialis and M. trossulus, respectively. Western blot analysis showed that the levels of mitochondrial sirtuin 5 (SIRT5) were generally three times higher and increased with acute heat stress in response to sirtuin inhibition in M. trossulus but not in M. galloprovincialis, suggesting a possible feedback response in the former species and a greater reliance on SIRT5 for its stress response. Our findings suggest that SIRT5 plays an important role in setting interspecific differences in stress tolerance in Mytilus by affecting the stress proteome.

A Canola Cultivar‐Testing Dataset Used to Calculate Stress Tolerance Indices and Crossover Interactions

Core Ideas Canola yield data were analyzed for 144 cultivars over 7 yr and 100 sites. Cultivars showed large differences for the stress tolerance index. Cultivars worthy of further stress‐tolerance studies were identified. G×E crossover analysis showed that adaptation was more often specific than general. Canola (Brassica napus L.) is a major temperate crop in Australia, and there is a dynamic commercial breeding industry producing new cultivars for growers. Improved stress tolerance in canola cultivars is of increasing importance, but it is difficult to detect and to breed for. Public‐sector researchers need reliable information on which existing cultivars possess good stress tolerance and can be used as germplasm sources for traits worthy of pre‐breeding research. We utilized the Australian National Variety Trial (NVT) data for released canola cultivars to examine two aspects of canola performance. First, the stress tolerance of cultivars was examined using low‐yielding vs. high‐yielding environments. Second, the genotype × environment interactions of cultivars were investigated and whether or not they exhibited significant crossover interaction, indicating general or specific adaptation. The NVT dataset consisted of results for 144 cultivars tested over 7 yr (2008–2014) at 101 locations and in 782 field plot experiments. Large differences in stress tolerance were seen in the data, and certain cultivars are recommended as candidates for further investigation. Many cultivars showed genotype × environment crossover interactions, indicating specific rather than general adaptation, although a few exceptional cultivars were high yielding and stable.

Per capita interactions and stress tolerance drive stress-induced changes in biodiversity effects on ecosystem functions.

Environmental stress changes the relationship between biodiversity and ecosystem functions, but the underlying mechanisms are poorly understood. Because species interactions shape biodiversity–ecosystem functioning relationships, changes in per capita interactions under stress (as predicted by the stress gradient hypothesis) can be an important driver of stress-induced changes in these relationships. To test this hypothesis, we measure productivity in microalgae communities along a diversity and herbicide gradient. On the basis of additive partitioning and a mechanistic community model, we demonstrate that changes in per capita interactions do not explain effects of herbicide stress on the biodiversity–productivity relationship. Instead, assuming that the per capita interactions remain unaffected by stress, causing species densities to only change through differences in stress tolerance, suffices to predict the stress-induced changes in the biodiversity–productivity relationship and community composition. We discuss how our findings set the stage for developing theory on how environmental stress changes biodiversity effects on ecosystem functions.

Cell-to-cell heterogeneity emerges as consequence of metabolic cooperation in a synthetic yeast community.

Cells that grow together respond heterogeneously to stress even when they are genetically similar. Metabolism, a key determinant of cellular stress tolerance, may be one source of this phenotypic heterogeneity, however, this relationship is largely unclear. We used self‐establishing metabolically cooperating (SeMeCo) yeast communities, in which metabolic cooperation can be followed on the basis of genotype, as a model to dissect the role of metabolic cooperation in single‐cell heterogeneity. Cells within SeMeCo communities showed to be highly heterogeneous in their stress tolerance, while the survival of each cell under heat or oxidative stress, was strongly determined by its metabolic specialization. This heterogeneity emerged for all metabolite exchange interactions studied (histidine, leucine, uracil, and methionine) as well as oxidant (H2O2, diamide) and heat stress treatments. In contrast, the SeMeCo community collectively showed to be similarly tolerant to stress as wild‐type populations. Moreover, stress heterogeneity did not establish as sole consequence of metabolic genotype (auxotrophic background) of the single cell, but was observed only for cells that cooperated according to their metabolic capacity. We therefore conclude that phenotypic heterogeneity and cell to cell differences in stress tolerance are emergent properties when cells cooperate in metabolism.

Tolerance to stress differs between Asian green mussels Perna viridis from the impacted Jakarta Bay and from natural habitats along the coast of West Java

It is an open question whether adverse habitat conditions, characteristic for many anthropogenically impacted coastal habitats, can determine resistance to abiotic stress in populations of residing invertebrates. We tested experimentally for differences in stress tolerance between individuals of the Asian green mussel Perna viridis stemming from the heavily impacted Jakarta Bay and from two natural sites, Lada Bay and Pelabuhan Ratu, West Java. Mussel performance under hyposalinity and hypoxia was assessed in laboratory assays by measuring fitness-related response variables, e.g. body condition index, relative shell weight, byssus production, respiration rates and survival. We found stress-specific and population-specific differences in mussel resistance to adverse conditions: Individuals from the impacted Jakarta Bay performed better under hypoxia than their conspecifics from the natural sites, whereas the latter were more resistant to hyposalinity. We explain these differences by differential acclimation to environmental conditions in the respective habitats and by diverging degrees of food supply.

Constraints on water use efficiency of drought tolerant maize grown in a semi-arid environment

Identifying the constraints on crop water use efficiency (WUE) will help develop strategies to mitigate these limitations, potentially guiding agronomic and irrigation management strategies as well as providing needed directions in breeding. Boundary functions identify the upper limits of yield per unit of crop water use, and are useful for identifying constraints on WUE. The objectives of this research were to (1) develop a boundary function for maize using data (n=260) from research projects conducted at Bushland, TX, and (2) compare the yields of two recently developed, drought tolerant maize (Zea mays L.) hybrids with the boundary function and examine possible abiotic and biotic constraints on maximizing water use efficiency. A commercially available hybrid and an experimental hybrid were grown in 2012 (high environmental stress environment) and 2013 (moderate stress environment) in 48 weighing lysimeters containing soil monoliths of either clay loam, silt loam, sandy loam, or fine sand in a rain shelter facility. Plant density was 8 plantsm−2; irrigation treatments were 50% and 80% replacement of predicted crop evapotranspiration. The high stress environment of large vapor deficits and high temperatures during early reproductive growth stages in 2012 compared with 2013 significantly constrained the yield potential of both hybrids. It also showed the difference in stress tolerance of the hybrids with significant differences in WUE, yield and yield components between hybrids. Soil textural class was a significant constraint on WUE and harvest index (HI), with larger WUE and HI from crops in the fine sand and sandy loam compared with those of the crops in the clay loam and silt loam. Continued increases in the tolerance of maize to abiotic and biotic stresses will be necessary to maintain maize production in the southern High Plains region as irrigation water resources decline.