Increased Stress Tolerance Research Articles

Autophagy: A New Avenue and Biochemical Mechanisms to Mitigate the Climate Change.

Autophagy is a preserved process in eukaryotes that allows large material degeneration and nutrient recovery via vacuoles or lysosomes in cytoplasm. Autophagy starts from the moment of induction during the formation of a phagophore. Degradation may occur in the autophagosomes even without fusion with lysosome or vacuole, particularly in microautophagosomes. This process is arbitrated by the conserved machinery of basic autophagy-related genes (ATGs). In selective autophagy, specific materials are recruited by autophagosomes via receptors. Selective autophagy targets a vast variety of cellular components for degradation, i.e., old or damaged organelles, aggregates, and inactive or misfolded proteins. In optimal conditions, autophagy in plants ensures cellular homeostasis, proper plant growth, and fitness. Moreover, autophagy is essential during stress responses in plants and aids in survival of plants. Several biotic and abiotic stresses, i.e., pathogen infection, nutrient deficiency, plant senescence, heat stress, drought, osmotic stress, and hypoxia induce autophagy in plants. Cell death is not a stress, which induces autophagy but in contrast, sometimes it is a consequence of autophagy. In this way, autophagy plays a vital role in plant survival during harsh environmental conditions by maintaining nutrient concentration through elimination of useless cellular components. This review discussed the recent advances regarding regulatory functions of autophagy under normal and stressful conditions in plants and suggests future prospects in mitigating climate change. Autophagy in plants offers a viable way to increase plant resilience to climate change by increasing stress tolerance and nutrient usage efficiency.

An Integrative Approach to the Development of the "Mental Retreat" Wellness Program to Prevent Early Aging

In today's society, where everyday challenges and pressures can significantly impact one's psych-emotional state, it is crucial to develop effective stress reduction strategies and maintain mental well-being. Prolonged stress, as recognized in global practice, can trigger the development of various ailments, such as cardiovascular pathologies, endocrine disorders, and psychosomatic deviations, and can also predispose individuals to autoimmune and oncological conditions. Furthermore, the influence of stressful situations over one's lifetime is a well-acknowledged risk factor that heightens the likelihood of early-onset age-associated illnesses and premature death. The primary objective of this study is to analyze and assess the effectiveness of health-promoting procedures in reducing stress levels and to develop a comprehensive wellness Program called "Mental Retreat." The application of this Program aims to mitigate the risk of various chronic diseases and preempt changes at the gene expression level to decelerate intracellular aging, enhance the body's antioxidant system, and stimulate the immune system. This work lays the groundwork for understanding the effects of procedures with substantial empirical support, highlighting synergistic influences in their combination, such as meditative practices, respiratory exercises, aromatherapy, outdoor physical activities, thermal and contrast procedures with elements of aroma and halotherapy, as well as lymphatic drainage massage effects, among others. The developed wellness Program is intended to be evaluated through dynamic observation and monitoring of integrative organism indicators: based on results from bioimpedance analysis (body composition), assessment of stress levels, and biological age accounting for the imbalance between the parasympathetic and sympathetic nervous systems and heart rate variability. Based on a global analysis of existing research, it has been found that the use of a variety of wellness methods has proven to improve concentration and overall psycho-emotional well-being, have a positive effect on the respiratory and cardiovascular systems, promote relaxation and improve sleep, strengthen the immune system and metabolism, increase stress tolerance, and can also have a positive effect on skin health. It's worth underscoring that the successful implementation of such a wellness Program could have immense implications for public healthcare by preventing the onset of numerous chronic diseases and contributing to an overall enhancement of quality of life.

Transformation of SNAC1 under Stress Inducible Promoter Rd29a Confers High Yield and Stress Tolerance in Rice

Abiotic stress tolerance in plants is often induced by activation of transcription factors. An increased stress tolerance was observed in indica rice cultivar BRRI dhan55 after transforming with the transcription factor SNAC1 (stress responsive NAC1) under stress inducible promoter rd29A that minimized unexpected phenotype and metabolic burden in transgenic lines. Tissue culture independent Agrobacterium-mediated in planta transformation method was used. Molecular analyses confirmed the successful integration of the SNAC1 gene and significantly higher gene expression level in the transgenic lines. The transgenic lines showed 3:1 segregation ratio at T2 generation following the Mendelian law of inheritance. Assays for leaf disk senescence and chlorophyll content at 100 mM and 200 mM salt and survival rates at 200 mM salt and drought conditions at 12 days of water withdrawal and after recovery under water showed significantly increased stress tolerance in the transgenics lines at seedling stage compared to the wild type. Enhanced yield, spikelet fertility, and 100 grain weight were observed at the reproductive stage compared to wild type under both salinity and drought stress conditions. Thus, SNAC1 expression in plants under inducible promoter is a better choice to enhance stress tolerance and yield under salinity and drought conditions. Plant Tissue Cult. & Biotech. 33(2): 115-133, 2023 (December)

Growth Performance of Soybean (Glycine max L. Merrill) treated with biochar under cadmium Stress

Cadmium (Cd) is a non-essential heavy metal that adversely affects plant growth. Biochar is predicted to facilitate plant growth. Under cadmium stress condition the effects of biochar on Soybean seedling growth, biomass production and SPAD value were poorly understood. In the current pot study Soybean was grown under different biochar and Cd combinations: 0% biochar and no Cd (control), 1.5% biochar, Cd (100 mg kg-1 of soil), Cd (100 mg kg-1 of soil) + 1.5% biochar. The results exhibited that under Cd stress shoot fresh weight (SFW), root fresh weight (RFW), shoot dry weight (SDW), root dry weight (RDW), shoot length (SL), root length (RL), whole plant biomass, stress tolerance index (%) and SPAD value decreased in Soybean, while root and shoot length ratio increased in comparison to control. Application of biochar solely or in addition of Cd enhanced SFW (14.07% with solely and 126.44% with Cd); RFW, SDW, RDW, SL and RL (156.66%, 55.89%, 61.29%, 21.14% and 16.62% with Cd, respectively), whole plant biomass (8.41% with sole biochar and 137.77% with Cd) and SPAD value (34.94% with Cd) in Cd-stressed Soybean. The sole application of biochar or Cd increased stress tolerance index (%) (SFSTI, RFSTI, SDSTI, RDSTI, SLSTI and RLSTIas recorded 114.04%, 92.25%, 104.47%, 105.78%, 100.73% and 99.22%, respectively; SFSTI, RFSTI, SDSTI, RDSTI, SLSTI and RLSTIvalue by 125.90%, 156.67%, 55.79%, 61.31%, 30.16% and 16.62% with Cd, respectively) in Cd-stressed Soybean. These results demonstrate that soil amendment with 1.5% biocharenhanced growth, biomass production and SPAD value of Soybean under Cd stress. It is therefore recommended that biochar can be used as effective tool to mitigate the detrimental effect of Cd stress on Soybean seedlings. South Asian J. Agric., Vol. 9, No.1&2, 2022-‘23: 22-30

Acute heat priming promotes short-term climate resilience of early life stages in a model sea anemone

Across diverse taxa, sublethal exposure to abiotic stressors early in life can lead to benefits such as increased stress tolerance upon repeat exposure. This phenomenon, known as hormetic priming, is largely unexplored in early life stages of marine invertebrates, which are increasingly threatened by anthropogenic climate change. To investigate this phenomenon, larvae of the sea anemone and model marine invertebrate Nematostella vectensis were exposed to control (18 °C) or elevated (24 °C, 30 °C, 35 °C, or 39 °C) temperatures for 1 h at 3 days post-fertilization (DPF), followed by return to control temperatures (18 °C). The animals were then assessed for growth, development, metabolic rates, and heat tolerance at 4, 7, and 11 DPF. Priming at intermediately elevated temperatures (24 °C, 30 °C, or 35 °C) augmented growth and development compared to controls or priming at 39 °C. Indeed, priming at 39 °C hampered developmental progression, with around 40% of larvae still in the planula stage at 11 DPF, in contrast to 0% for all other groups. Total protein content, a proxy for biomass, and respiration rates were not significantly affected by priming, suggesting metabolic resilience. Heat tolerance was quantified with acute heat stress exposures, and was significantly higher for animals primed at intermediate temperatures (24 °C, 30 °C, or 35 °C) compared to controls or those primed at 39 °C at all time points. To investigate a possible molecular mechanism for the observed changes in heat tolerance, the expression of heat shock protein 70 (HSP70) was quantified at 11 DPF. Expression of HSP70 significantly increased with increasing priming temperature, with the presence of a doublet band for larvae primed at 39 °C, suggesting persistent negative effects of priming on protein homeostasis. Interestingly, primed larvae in a second cohort cultured to 6 weeks post-fertilization continued to display hormetic growth responses, whereas benefits for heat tolerance were lost; in contrast, negative effects of short-term exposure to extreme heat stress (39 °C) persisted. These results demonstrate that some dose-dependent effects of priming waned over time while others persisted, resulting in heterogeneity in organismal performance across ontogeny following priming. Overall, these findings suggest that heat priming may augment the climate resilience of marine invertebrate early life stages via the modulation of key developmental and physiological phenotypes, while also affirming the need to limit further anthropogenic ocean warming.

Malate production, sugar metabolism, and redox homeostasis in the leaf growth zone of Rye (Secale cereale) increase stress tolerance to aluminum stress: A biochemical and genome‐wide transcriptional study

Global soil acidification is increasing, enlarging aluminum (Al) availability in soils, leading to reductions in plant growth. This study investigates the effect of Al stress on the leaf growth zones of Rye (Secale cereale, cv Beira). Kinematic analysis showed that the effect of Al on leaf growth rates was mainly due to a reduced cell production rate in the meristem. Transcriptomic analysis identified 2272 significantly (log2fold > |0.5| FDR < 0.05) differentially expressed genes (DEGs) for Al stress. There was a downregulation in several DEGs associated with photosynthetic processes and an upregulation in genes for heat/light response, and H2O2 production in all leaf zones. DEGs associated with heavy metals and malate transport were increased, particularly, in the meristem. To determine the putative function of these processes in Al tolerance, we performed biochemical analyses comparing the tolerant Beira with an Al sensitive variant RioDeva. Beira showed improved sugar metabolism and redox homeostasis, specifically in the meristem compared to RioDeva. Similarly, a significant increase in malate and citrate production, which are known to aid in Al detoxification in plants, was found in Beira. This suggests that Al tolerance in Rye is linked to its ability for Al exclusion from the leaf meristem.

Integrated Action of Rhizobacteria with Aloe vera and Moringa Leaf Extracts Improves Defense Mechanisms in Hibiscus sabdariffa L. Cultivated in Saline Soil.

Osmotic stress is a serious physiological disorder that affects water movement within the cell membranes. Osmotic stress adversely affects agricultural production and sustainability and is largely caused by soil salinity and water stress. An integrated nitrogen-fixing bacteria (NFB) soil amendment and an exogenous foliar application of Aloe vera leaf extract (ALE), and moringa leaf extract (MLE) were evaluated on roselle (Hibiscus sabdariffa L.) growth, calyx yield, secondary metabolites, and tolerance to osmotic stress in salt-affected soil. The osmotic stress markedly decreased above- and below-ground development of the roselle plant, but integrated NFB soil amendment with ALE or MLE foliar application significantly alleviated its negative impacts. Broadly, an improvement was observed in chlorophyll, carbohydrates, and protein levels following NFB and extracts foliar application, as well as a significant enhancement in antioxidant production (total phenols, ascorbic acid, and FRAP), which decreased peroxide production and increased stress tolerance in plants. Under osmotic stress, the roselle calyx revealed the highest anthocyanin levels, which declined following NFB soil amendment and foliar extract application. Additionally, an enhancement in nitrogen (N), phosphorus (P), and potassium (K) contents and the K/Na ratio, along with a depression in sodium (Na) content, was noticed. The integrated application of Azospirillum lipoferum × ALE exhibited the best results in terms of enhancing above- and below-ground growth, calyx yield, secondary metabolites, and tolerance to osmotic stress of the roselle plants cultivated in the salt-affected soil.

Evaluation of Morpho-Physiological and Yield-Associated Traits of Rice (Oryza sativa L.) Landraces Combined with Marker-Assisted Selection under High-Temperature Stress and Elevated Atmospheric CO2 Levels.

Rice (Oryza sativa L.) is an important cereal crop worldwide due to its long domestication history. North-Eastern India (NEI) is one of the origins of indica rice and contains various native landraces that can withstand climatic changes. The present study compared NEI rice landraces to a check variety for phenological, morpho-physiological, and yield-associated traits under high temperatures (HTs) and elevated CO2 (eCO2) levels using molecular markers. The first experiment tested 75 rice landraces for HT tolerance. Seven better-performing landraces and the check variety (N22) were evaluated for the above traits in bioreactors for two years (2019 and 2020) under control (T1) and two stress treatments [mild stress or T2 (eCO2 550 ppm + 4 °C more than ambient temperature) and severe stress or T3 (eCO2 750 ppm + 6 °C more than ambient temperature)]. The findings showed that moderate stress (T2) improved plant height (PH), leaf number (LN), leaf area (LA), spikelets panicle-1 (S/P), thousand-grain weight (TGW), harvest index (HI), and grain production. HT and eCO2 in T3 significantly decreased all genotypes' metrics, including grain yield (GY). Pollen traits are strongly and positively associated with spikelet fertility at maturity and GY under stress conditions. Shoot biomass positively affected yield-associated traits including S/P, TGW, HI, and GY. This study recorded an average reduction of 8.09% GY across two seasons in response to the conditions simulated in T3. Overall, two landraces-Kohima special and Lisem-were found to be more responsive compared to other the landraces as well as N22 under stress conditions, with a higher yield and biomass increment. SCoT-marker-assisted genotyping amplified 77 alleles, 55 of which were polymorphic, with polymorphism information content (PIC) values from 0.22 to 0.67. The study reveals genetic variation among the rice lines and supports Kohima Special and Lisem's close relationship. These two better-performing rice landraces are useful pre-breeding resources for future rice-breeding programs to increase stress tolerance, especially to HT and high eCO2 levels under changing climatic situations.

Mechanisms of increasing stress tolerance during transcranial magnetic stimulation in people with intellectual work

Mechanisms of increasing stress tolerance during transcranial magnetic stimulation in people with intellectual work

A 10-year longitudinal study of dental students' emotional intelligence and the impact of COVID-19.

Emotional intelligence (EI) supports the clinical and social competencies of a practicing dentist. Reuven Bar-On's EI model is an array of inter-related emotional and social competencies, skills, and behaviors, which consist of five key domains: Self-Perception, Self-Expression, Interpersonal, Decision Making, and Stress Management, and associated with the domains are 15 emotional quotient (EQ) subskills. This study measured the impact of COVID-19 on dental students' EI by comparing measures pre-COVID-19 and during COVID-19 matriculation. This retrospective longitudinal study measured EI with the EQ-i 2.0 for higher education. Dental students completed an EQ-i 2.0 assessment (Attempt) at the beginning of matriculation, at the mid-point, and prior to graduation. Ten groups were included, of which the first three completed matriculation prior to the pandemic and the remaining seven matriculated during timeframes intersecting at different times during the pandemic. A paired t-test dependent sample of means (p≤0.05) compared EQ scores for each attempt for all groups. The study compared means for three EQ attempts with the t-test independent sample of means (p≤0.05) for cohorts matriculating pre-COVID-19 and during COVID-19. The pre-COVID-19 groups showed significant increases in EQ with each subsequent attempt. COVID-19-impacted groups demonstrated significant increase in Stress Tolerance and significant decreases, most notably in the domains of Interpersonal and Self-Perception, and subscales of Optimism and Happiness. COVID-19-related stressors impacted dental students' EI as multiple EI areas declined significantly. Dental educators should minimize organizational stressors and support EI during years 2 and 3 of matriculation.

Microbial Biofilms: Harnessing the Power of Complex Microbial Communities for Industrial Applications

Microbial biofilms are complex microbial colonies that attach to surfaces and grow inside an extracellular polymeric substance (EPS) matrix. These biofilms have great promise for industrial applications and play crucial roles in several natural and artificial systems. The use of microbial biofilms in industrial settings is examined in this abstract, which also places an emphasis on techniques to improve biofilm development and performance through surface modification and quorum sensing manipulation. Due to their versatility, durability, and cooperative behaviour, biofilms have attracted interest and are useful in a variety of industrial industries. They work in the food business, bioenergy generation, agriculture industry and biosensor, among other fields.Biofilms are more effective in industrial processes because of their intricate interactions, which also lead to higher metabolic capacities, increased stress tolerance, and improved retention of immobilised cells. The production and performance of microbial biofilms need to be improved in order to fully realise their potential. Techniques for surface modification provide a promising way to customise the characteristics of biofilms. It is possible to modify the topography, hydrophobicity, and charge of the substrate to affect how quickly biofilms form after initial microbial attachment. Additionally, functionalization and coatings based on nanomaterials provide novel approaches to improve biofilm adhesion, cohesiveness, and stability. The method of cell-to-cell communication known as quorum sensing (QS) directs the development and behaviour of biofilms. Controlling QS pathways enables fine-grained regulation of biofilm growth. QS may be controlled via genetic engineering and small molecule therapy, which affects the phenotypic and architecture of biofilms. With the use of these techniques, biofilms may be designed with the required properties, including greater thickness, higher resistance to shear pressures, and increased production of desirable chemicals. In conclusion, because of their cooperative nature and adaptable functioning, microbial biofilms show enormous promise for industrial applications. The importance of surface modification and quorum sensing modulation as tactics to improve biofilm performance is highlighted in this abstract. As science advances, a fuller comprehension of the ecology of biofilms, interspecies interactions, and synthetic biology technologies will make it easier to create biofilms that are specifically suited to a given industrial purpose. Understanding the complex principles underlying biofilm production and behaviour will allow for the full realisation of the promise for sustainable and effective industrial processes, ushering in a new age of biofilm-based technology.

Hydrogen peroxide signal photosynthetic acclimation of Solanum lycopersicum L. cv Micro-Tom under water deficit

The current climate change setting necessitates the development of methods to mitigate the effects of water scarcity to ensure the sustainability of agricultural activities.f Hydrogen peroxide (H2O2) is a plant signaling molecule that can trigger metabolic defense mechanisms in response to adverse environmental circumstances like as drought. The purpose of this study was to investigate if foliar application of H2O2 stimulates modifications in photosynthetic metabolism for adaptation of tomato plants to a period of water deficit and recovery. The study, which was carried out in a factorial scheme, tested plants subjected to two water conditions (well-watered plants and plants subjected to water deficit), as well as foliar application of 1 mM H2O2 (zero, one, or two applications, 24 h after the first), and was evaluated in two moments, during the deficit period and after recovery. Foliar application of 1 mM H2O2 resulted in a 69% increase in the maximum rate of RuBisCO carboxylation in well-watered plants, contributing to tomato photosynthetic adjustment. H2O2 treatment resulted in a 37% increase in dry mass in these plants. In plants subjected to water deficiency, 2× H2O2 increased stress tolerance by reducing the maximal rate of RuBisCO carboxylation by only 18%, but in plants that did not receive H2O2 treatment, the reduction was 86% in comparison to the wet plants. Plants exposed to a water shortage and given 2× H2O2 stored sucrose in the leaves and had a 17% higher relative water content than plants not given H2O2. Thus, H2O2 foliar treatment can be used in tomato management to induce drought tolerance or to boost photosynthetic activity and dry mass formation in well-watered plants.

Self-grafting induced epigenetic changes leading to drought stress tolerance in tomato plants.

Grafting is widely used as a method to increase stress tolerance in good fruiting lines of Solanaceae plants. However, little is known about how grafting, affects epigenetic modifications and leads to stress tolerance, especially within the same line. Here, we studied the effects of self-grafting in tomato plants on histone and DNA modifications and changes in gene expression related to drought stress. We found that at the 3-leaf stage, one week after self-grafting, histone H3 K4 trimethylation and K27 trimethylation changes were observed in more than 500 genes each, and DNA methylation changes in more than 5,000 gene regions at the shoot apex compared to the non-grafted control. In addition, two weeks after the epigenomic changes, global expression changes continued to be observed at the shoot apex in several genes related to the metabolic process of nitrogen compounds, responses to stimulus, chromosome organization, cell cycle-related genes, and regulation of hormone levels. Finally, these grafted seedlings acquired remarkable drought tolerance, suggesting that epigenomic modifications during the wound-healing process mitigate stress tolerance in tomato plants.

Ethylene-mediated metabolic priming increases photosynthesis and metabolism to enhance plant growth and stress tolerance.

Enhancing crop yields is a major challenge because of an increasing human population, climate change, and reduction in arable land. Here, we demonstrate that long-lasting growth enhancement and increased stress tolerance occur by pretreatment of dark grown Arabidopsis seedlings with ethylene before transitioning into light. Plants treated this way had longer primary roots, more and longer lateral roots, and larger aerial tissue and were more tolerant to high temperature, salt, and recovery from hypoxia stress. We attributed the increase in plant growth and stress tolerance to ethylene-induced photosynthetic-derived sugars because ethylene pretreatment caused a 23% increase in carbon assimilation and increased the levels of glucose (266%), sucrose/trehalose (446%), and starch (87%). Metabolomic and transcriptomic analyses several days posttreatment showed a significant increase in metabolic processes and gene transcripts implicated in cell division, photosynthesis, and carbohydrate metabolism. Because of this large effect on metabolism, we term this "ethylene-mediated metabolic priming." Reducing photosynthesis with inhibitors or mutants prevented the growth enhancement, but this was partially rescued by exogenous sucrose, implicating sugars in this growth phenomenon. Additionally, ethylene pretreatment increased the levels of CINV1 and CINV2 encoding invertases that hydrolyze sucrose, and cinv1;cinv2 mutants did not respond to ethylene pretreatment with increased growth indicating increased sucrose breakdown is critical for this trait. A model is proposed where ethylene-mediated metabolic priming causes long-term increases in photosynthesis and carbohydrate utilization to increase growth. These responses may be part of the natural development of seedlings as they navigate through the soil to emerge into light.

Divergent endophytic viromes and phage genome repertoires among banana (Musa) species.

Viruses generally cause disease, but some viruses may be beneficial as resident regulators of their hosts or host microbiomes. Plant-associated viruses can help plants survive by increasing stress tolerance or regulating endophytic communities. The goal of this study was to characterize endophytic virus communities in banana and plantain (Musa spp.) genotypes, including cultivated and wild species, to assess virome repertoires and detect novel viruses. DNA viral communities were characterized by shotgun sequencing of an enriched endosphere extract from leaves and roots or corm of 7 distinct Musa genotypes (M. balbisiana, Thai Black, M. textilis, M. sikkimensis, Dwarf Cavendish, Williams Hybrid, and FHIA-25 Hybrid). Results showed abundant virus-like contigs up to 108,191 bp long with higher relative abundance in leaves than roots. Analyses predicted 733 phage species in 51 families, with little overlap in phage communities among plants. Phage diversity was higher in roots and in diploid wild hosts. Ackermanniviridae and Rhizobium phage were generally the most abundant taxa. A Rhizobium RR1-like phage related to a phage of an endophytic tumor-causing rhizobium was found, bearing a holin gene and a partial Shiga-like toxin gene, raising interest in its potential to regulate endophytic Rhizobiaceae. Klebsiella phages were of interest for possible protection against Fusarium wilt, and other phages were predicted with potential to regulate Erwinia, Pectobacterium, and Ralstonia-associated diseases. Although abundant phage-containing contigs were functionally annotated, revealing 1,038 predicted viral protein domains, gene repertoires showed high divergence from database sequences, suggesting novel phages in these banana cultivars. Plant DNA viruses included 56 species of Badnavirus and 26 additional non-Musa plant viruses with distributions that suggested a mixture of resident and transient plant DNA viruses in these samples. Together, the disparate viral communities in these plants from a shared environment suggest hosts drive the composition of these virus communities. This study forms a first step in understanding the endophytic virome in this globally important food crop, which is currently threatened by fungal, bacterial, and viral diseases.

New seed coating containing Trichoderma viride with anti-pathogenic properties.

To ensure food security in the face of climate change and the growing world population, multi-pronged measures should be taken. One promising approach uses plant growth-promoting fungi (PGPF), such as Trichoderma, to reduce the usage of agrochemicals and increase plant yield, stress tolerance, and nutritional value. However, large-scale applications of PGPF have been hampered by several constraints, and, consequently, usage on a large scale is still limited. Seed coating, a process that consists of covering seeds with low quantities of exogenous materials, is gaining attention as an efficient and feasible delivery system for PGPF. We have designed a new seed coating composed of chitin, methylcellulose, and Trichoderma viride spores and assessed its effect on canola (Brassica napus L.) growth and development. For this purpose, we analyzed the antifungal activity of T. viride against common canola pathogenic fungi (Botrytis cinerea, Fusarium culmorum, and Colletotrichum sp.). Moreover, the effect of seed coating on germination ratio and seedling growth was evaluated. To verify the effect of seed coating on plant metabolism, we determined superoxide dismutase (SOD) activity and expression of the stress-related RSH (RelA/SpoT homologs). Our results showed that the T. viride strains used for seed coating significantly restricted the growth of all three pathogens, especially F. culmorum, for which the growth was inhibited by over 40%. Additionally, the new seed coating did not negatively affect the ability of the seeds to complete germination, increased seedling growth, and did not induce the plant stress response. To summarize, we have successfully developed a cost-effective and environmentally responsible seed coating, which will also be easy to exploit on an industrial scale.

Escherichia coli Aggregates Mediated by Native or Synthetic Adhesins Exhibit Both Core and Adhesin-Specific Transcriptional Responses.

Bacteria can rapidly tune their physiology and metabolism to adapt to environmental fluctuations. In particular, they can adapt their lifestyle to the close proximity of other bacteria or the presence of different surfaces. However, whether these interactions trigger transcriptomic responses is poorly understood. We used a specific setup of E. coli strains expressing native or synthetic adhesins mediating bacterial aggregation to study the transcriptomic changes of aggregated compared to nonaggregated bacteria. Our results show that, following aggregation, bacteria exhibit a core response independent of the adhesin type, with differential expression of 56.9% of the coding genome, including genes involved in stress response and anaerobic lifestyle. Moreover, when aggregates were formed via a naturally expressed E. coli adhesin (antigen 43), the transcriptomic response of the bacteria was more exaggerated than that of aggregates formed via a synthetic adhesin. This suggests that the response to aggregation induced by native E. coli adhesins could have been finely tuned during bacterial evolution. Our study therefore provides insights into the effect of self-interaction in bacteria and allows a better understanding of why bacterial aggregates exhibit increased stress tolerance. IMPORTANCE The formation of bacterial aggregates has an important role in both clinical and ecological contexts. Although these structures have been previously shown to be more resistant to stressful conditions, the genetic basis of this stress tolerance associated with the aggregate lifestyle is poorly understood. Surface sensing mediated by different adhesins can result in various changes in bacterial physiology. However, whether adhesin-adhesin interactions, as well as the type of adhesin mediating aggregation, affect bacterial cell physiology is unknown. By sequencing the transcriptomes of aggregated and nonaggregated cells expressing native or synthetic adhesins, we characterized the effects of aggregation and adhesin type on E. coli physiology.

ENHANCING GROWTH OF LEUCAENA LEUCOCEPHALA SEEDLINGS BY STIMULATION OF SYMBIOTIC RELATIONSHIP BETWEEN VESICULAR ARBUSCULAR MYCORRHIZAL (VAM) AND NITROGEN FIXING BACTERIA UNDER PHOSPHATE ROCK FERTILIZATION

) with rhizobia are the main contributors to improve its ecological, physiological, and commercial significance. Leucaena is an appropriate species to serve as a model for other woody legumes because of these traits. Therefore, its symbiotic relationship with mycorrhizal fungus has attracted a lot of interest. Plant stress responses can be mediated by vesicular arbuscular mycorrhizal fungal (VAM) symbionts via increasing stress tolerance. The study was carried out in a greenhouse at the private nursery in Itay El-Baroud city and the Laboratories of the Horticulture Department, Faculty of Agriculture, Damanhour University, in collaboration with the Laboratories of the Soil and Water Development Center, Damanhour, El-Beheira Governorate, Egypt, over two consecutive seasons, 2020 and 2021. This study was conducted to determine the effect of dual inoculation with endomycorrhizal fungi (VAM) and

Abstract P6-14-18: Effect of 3q oncogene SEC62 on migration and proliferation of triple-negative breast cancer cells

Abstract Background Chromosome 3q26 amplifications represent a frequent alteration in various cancer entities including breast cancer. SEC62 – a 3q26 encoded gene – was identified as a potential onco- and tumor-driver gene for the pathogenesis of breast cancer. Although the precise physiological function of the respective protein Sec62 is not completely understood, Sec62 seems to induce an increased stress tolerance, enhanced cell migration and invasive potential in SEC62 overexpressing cells. SEC62 overexpressing breast cancer patients have been shown to have a higher rate of lymph node metastasis and poorer overall prognosis. Hence, we aimed to further evaluate the effect of Sec62 for triple-negative breast cancer by targeting cell migration and proliferation of triple-negative cell lines altered in their SEC62 expression. Objectives The aim of this study was to investigate the role of Sec62 for triple-negative breast cancer in cell culture using functional analyzes comparing cell migration and cell proliferation in triple-negative cell lines using the effects of siRNA-mediated Sec62 depletion in vitro. Material&amp; Methods In this study, three SEC62 gene silencing experiments each with two different siRNAs directed against the SEC62 mRNA were carried out in comparison to a control siRNA in combination with cell proliferation and cell migration tests plus Western blots for the triple-negative breast cancer cell line CAL120 in order to determine the suspected causal relationship between SEC62- overexpression and an increased cell migration and thus an enhanced invasion potential of the cancer cells. The cell proliferation was examined in real time in the 96 well xCELLigence system and the cell migration using Fluoroblock without matrigel using fluorescence microscopy. Results In cell migration assays, the median migrated cell number in the control siRNA group was 263 (241-279), the cell number in the groups of the two siRNAs directed against the Sec62 mRNA was 72 (70-149) and 178 (96-276) (p &amp;lt; 0.01). In cell proliferation assays, the median cell index in the control siRNA group was 7.5 (7.4-7.6), while it was 7.4 (7.3-7 .5) and 7.6 (7.5-7.7) (p=0.37). In the first analyzes of the medians of the three gene silencing experiments of the cell line CAL120, the expected negative effect of the SEC62-siRNA on cell migration is confirmed, while, as expected, the effect on cell proliferation remains unchanged with decreasing Sec62 content. Conclusion In this in vitro study using cell migration and cell proliferation assays we found a correlation between SEC62 overexpression and increased cell migration. This implies a potential association between Sec62 and an increased tumor cell invasion in triple-negative breast cancer. Citation Format: Julia SM Zimmermann, Annika Cullmann, Askin Kaya, Merle Doerk, Maximilian Linxweiler, Marc P Radosa, Sven Lang, Martin Jung, Erich F Solomayer, Julia C Radosa. Effect of 3q oncogene SEC62 on migration and proliferation of triple-negative breast cancer cells [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P6-14-18.

Seed treatments with salicylic and succinic acid to mitigate drought stress in flowering kale cv. 'Red Pigeon F1'

Drought, which is increasingly in important worldwide because of climate change, has also become an existential threat to bedding plants. This study aimed to determine the effect of salicylic and succinic acid on the physiological and biochemical traits of flowering kale plants grown under drought stress. Seeds of the Brassica oleracea (Acephala group) cv. 'Red Pigeon F1′ were used as plant material. The seeds were treated with 3 different concentrations of succinic acid (0.5 mM, 1.0 mM, and 2.0 mM) and salicylic acid (0.5 mM, 1.0 mM, 2.0 mM). In the early seedling stage, the untreated seedlings (the negative control) and seedlings treated with succinic and salicylic acid were exposed to severe drought stress conditions while the positive control (no treatment) was watered to 100% of its field capacity. The experiment was terminated when symptoms of drought stress were observed in 50% of the seedlings in the negative control group. Relative chlorophyll content, stomatal conductance, leaf temperature, leaf relative water content, leaf area, membrane permeability, lipid peroxidation, proline content and antioxidant enzyme activity were recorded. As a result of the study, succinic and salicylic acid were found to be effective in countering stress mechanisms of flowering kale seedlings. The MDA content (58.56 nmol g−1 FW) and membrane injury (43.12%) reached the highest value in untreated seedlings under drought conditions. Antioxidant enzyme activities, relative chlorophyll content and proline content of seedlings treated with succinic and salicylic acid were higher than both the negative control and positive control. The 2.0 mM succinic acid and 2.0 mM salicylic acid treatments improved the stomatal conductance by 69.39% and 68.43%. Leaf relative water content was also better in drought-stressed seedlings treated with succinic and salicylic acid compared to the negative control. The results of the study showed that drought stress tolerance increased in flowering kale after both salicylic and succinic acid treatments. Succinic acid can be an elicitor candidate and it might be used to increase stress tolerance in plants.