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The utilization of chelated fertilizers at specific concentrations could serve as an efficient method to mitigate the effects of drought stress in plants, considering it a global climatic issue. The objective of this study was to ascertain the influence of potassium and zinc chelate fertilizers on improving drought tolerance in quinoa plants. The experiment was conducted over two cropping years, 2018–2019 and 2019–2020. It followed a split-plot factorial design within a randomized complete block layout, in three replicates. The results indicated that the foliar application of the combined treatment of 50K + 50Zn significantly increased grain yield, particularly in the Q26 cultivar, under drought-stress conditions. However, the best harvest index was related to the Q26 cultivar under 100Zn application conditions. Nevertheless, the application of chelated fertilizers significantly enhanced these traits under stress compared to the non-application conditions. Furthermore, the content of glycine betaine and proline in the plant increased under the influence of 100K and 100Zn applications in the Q29 cultivar in 25% FC. Based on the obtained results for Catalase enzyme activity at 25% FC and in the presence of 100Zn foliar application and for Peroxidase at 25% FC and the presence of the combined 50K + 50Zn foliar application in the Q29 cultivar, the highest activity of these enzymes was observed. Consequently, considering the increased contents of glycine betaine and proline in the foliar application, as well as the enhanced activity of antioxidant enzymes contributing to improved drought tolerance in these plants, the application of potassium and zinc chelates as fertilizers is recommended. [ABSTRACT FROM AUTHOR]

Salt stress is a major abiotic factor that negatively impacts the growth, performance, and secondary metabolite production in pepper (Capsicum annuum L.) plants. Brassinosteroids (BRs) play a crucial role in enhancing plant tolerance to abiotic stress, yet their potential in mitigating salt stress in pepper plants, particularly by promoting sugar and glycine betaine accumulation, remains underexplored. In this study, we investigated the effects of the foliar application of 2,4-epibrassinolide (EBR) on salt-stressed pepper seedlings. Our findings revealed that EBR treatment significantly increased the levels of proline, sugar, and glycine betaine under salt stress compared to untreated controls. Moreover, EBR enhanced the antioxidant defense mechanisms in pepper seedlings by increasing sugar and glycine betaine levels, which contributed to the reduction of reactive oxygen species (ROS) and malondialdehyde (MDA) accumulation. [ABSTRACT FROM AUTHOR]

Drought is considered the main agricultural menace, limiting the successful realization of land potential, and thereby reducing crop productivity worldwide. Therefore, breeding maize hybrids with improved drought tolerance via genetic manipulation is necessary. Herein, the multiple bud clumps of elite inbred maize lines, DH4866, Qi319, Y478 and DH9938, widely used in China, were transformed with the Escherichia coli betA gene encoding choline dehydrogenase (EC 1.1.99.1), a key enzyme in the biosynthesis of glycine betaine from choline, using Agrobacterium to generate betA transgenic lines. After 3–4 consecutive generations of self-pollination in these transgenic plants, progenies with a uniform appearance, excellent drought tolerance, and useful agricultural traits were obtained. We evaluated the drought tolerance of T4 progenies derived from these transgenic plants in the field under reduced irrigation. We found that a few lines exhibited much higher drought tolerance than the non-transformed control plants. Transgenic plants accumulated higher levels of glycine betaine and were relatively more tolerant to drought stress than the controls at both the germination and early seedling stages. The grain yield of the transgenic plants was significantly higher than that of the control plants after drought treatment. Drought-tolerant inbred lines were mated and crossed to create hybrids, and the drought tolerance of these transgenic hybrids was found to be enhanced under field conditions compared with those of the non-transgenic (control) plants and two other commercial hybrids in China. High yield and drought tolerance were achieved concurrently. These transgenic inbred lines and hybrids were useful in marginal and submarginal lands in semiarid and arid regions. The betA transgene can improve the viability of crops grown in soils with sufficient or insufficient water. [ABSTRACT FROM AUTHOR]

A highly selective biosensor for glycine betaine (GB) based on the curcumin derivative (1BHD) is described, which displays a significant visual change and a lower detection limit (76 nM). The GB sensor displays a 1:1 binding ratio and a binding constant of 9.042 × 107 M−1. The binding mechanism of 1BHD for glycine betaine was confirmed by 1H NMR titration, mass spectrometry, and DFT calculation. The fluorescence intensity of 1BHD was selectively quenched by GB, and an obvious color change from yellow to orange was observed by the naked eye. The above results have been utilized to detect GB sensitively in blood and urine samples. [ABSTRACT FROM AUTHOR]

Sweet cherries are among consumers' preferred fresh fruits, known for their attractive organoleptic properties and high nutritional value. Agronomical practices, which are now shifting to more environmentally sustainable options, can influence several key quality traits of sweet cherries. In this context, reducing conventional agrochemicals and increasing the application of preharvest biostimulants has emerged as an innovative strategy. This approach can not only enhance cherry production and quality but also ensure the economic and environmental sustainability of the cherry supply chain. Hence, this work is aimed at studying the effect of the application of two concentrations of glycine betaine (GB) and Ecklonia maxima-based (EM) biostimulants, and their combination, in two cultivars of sweet cherry: the early-maturing 'Early Bigi' and the late-maturing 'Lapins', both grafted onto SL-64 rootstock. Evaluated parameters included fruit weight and dimensions, color, firmness, total soluble solids (TSS), titratable acidity (TA), phenolic and anthocyanin contents, and sensory profile. Key findings highlight that, with a few exceptions, biostimulant treatments had a positive impact on the studied parameters, although the responses varied between cultivars. For instance, fruit size increased by 13.41% in 'Early Bigi' and 47.20% in 'Lapins'. Additionally, reduced color values, coupled with higher TSS/TA ratios, indicate advanced fruit maturation, which could allow for an earlier harvest. The total phenolic content rose by 56.88% in 'Early Bigi' and 30.24% in 'Lapins', while anthocyanin levels surged by 88.28% and 36.10%, respectively. Fruit firmness also improved following biostimulant application. Sensory analysis further revealed enhancements in key descriptors such as "overall aspect", "firmness", and "cherry flavor", underscoring the beneficial effects of these treatments. These combined results indicate that the preharvest application of glycine betaine or Ecklonia maxima-based (EM) biostimulants significantly improves key quality traits of sweet cherries. This approach offers benefits not only from a commercial perspective but also for the sweet cherry supply chain sustainability by reducing the application of chemical-based products and replacing them with ecofriendly substances while enhancing the quality of the fruit. [ABSTRACT FROM AUTHOR]

[Display omitted] Seeking effective ways to maintain cellular homeostasis is crucial to the survival of organisms when they encounter osmotic stress. Glycine betaine (GB) is a widely generated natural osmolyte, but its endogenous production and action are limited. Herein, a kind of nonionic surfactant dodecyl-β-d-glucopyranoside (DG) and a common polymer polyethylene glycol (PEG) are proven to have the ability to enhance the osmotic stress (induced by sugar concentration changes) tolerance of cell and organism models, those are giant unilamellar vesicles (GUVs) and gram-negative Escherichia coli. DG or PEG only induces small size decrease and certain shape change of GUVs. Importantly, DG or PEG at the concentration 100 times lower than that of GB effectively increases the survival rate of bacteria under both hypoosmotic and hyperosmotic conditions. This intriguing result is attributed to the insertion of DG or adsorption of PEG in the lipid bilayer membrane, leading to enhanced membrane permeability. These exogenous substances can replace GB to facilely and highly efficiently augment adaptation of organisms to osmotic stress. [ABSTRACT FROM AUTHOR]

Lead (Pb) toxicity is a major environmental threat that severely affects growth and production of staple crops. Foliar applications of glycine betaine (GB) have been extensively studied for their ability to stimulate heavy metals (HMs) tolerance in plants. Despite that, no literature reports are available on the ameliorative behavior of GB application on barley cultivars under Pb stress. A pot experiment was conducted to assess the relative efficacy of exogenous GB (2 mM) supplementation on various morphological (spike length) yield (no. of spikelet spike−1, no. of grains spike−1, grain yield plant−1, and 1000 grain weight) and grain quality traits (carbohydrate and protein content) of two barley cultivars (BH946 & BH959) under three levels of Pb stress treatments, viz. control, 15, 25, and 35 mM. Current research results revealed that Pb stress significantly (p < 0.05) decreased barley plants' yield traits and grain quality characteristics. More reduction was observed at the highest Pb stress, i.e., 35 mM. However, the foliar application of GB significantly (p < 0.05) mitigates the toxic effect of Pb stress and improves the yield traits, and ultimately, the grain yield per plant increases. Moreover, GB addition also enhances the quality of barley grain by improving the protein and carbohydrate content. The present research findings exhibit the ameliorative role of foliar-applied GB in enhancing the yield, and quality traits of barley cultivars might be attributed to modulating plant growth, photosynthetic activities, the antioxidant defense system, and diminished oxidative stress under Pb toxicity. According to the t-test results, both cultivars displayed the same trend under each stress and GB supplement. Therefore, only one cultivar can be considered for the experiment setup out of the two for further studies. In conclusion, GB at 2 mM concentrations successfully mitigates the toxic effect of Pb (up to 35 mM) and its implication might be recommended for crops suffering from Pb stress to improve their yield and quality traits. [ABSTRACT FROM AUTHOR]

Abstract Halophiles are one of the classes of extremophilic microorganisms that can flourish in environments with very high salt concentrations. In this study, fifteen bacterial strains isolated from various crop rhizospheric soils of agricultural fields along the Southwest coastline of Saurashtra, Gujarat, and identified by 16S rRNA gene sequencing as Halomonas pacifica, H. stenophila, H. salifodinae, H. binhaiensis, Oceanobacillus oncorhynchi, and Bacillus paralicheniformis were investigated for their potentiality to produce extremozymes and compatible solute. The isolates showed the production of halophilic protease, cellulase, and chitinase enzymes ranging from 6.90 to 35.38, 0.004–0.042, and 0.097–0.550 U ml−1, respectively. The production of ectoine-compatible solute ranged from 0.01 to 3.17 mg l−1. Furthermore, the investigation of the ectoine-compatible solute production at the molecular level by PCR showed the presence of the ectoine synthase gene responsible for its biosynthesis in the isolates. Besides, it also showed the presence of glycine betaine biosynthetic gene betaine aldehyde dehydrogenase in the isolates. The compatible solute production by these isolates may be linked to their ability to produce extremozymes under saline conditions, which could protect them from salt-induced denaturation, potentially enhancing their stability and activity. This correlation warrants further investigation.

A field experiment was carried out during the spring season of 2022 at Research Station No.2, College of Agriculture, University of Anbar. The experiment followed a randomized complete block design (RCBD) in a split-plot arrangement with three replications to study the effect of four concentrations of Glycine Betaine acid (0, 50, 100, 150 mg L-1), denoted as GB2, GB3, and GB4 respectively, on some biochemical traits of mung bean under water stress conditions. The water stress levels were S1 (irrigated with 100% of available water, serving as the control treatment), and S2, S3, and S4, representing depletion rates of 25%, 50%, and 75% of available water, respectively. The results showed that the GB4 concentration was superior in total chlorophyll content in leaves (1.677 mg g-1), relative water content (55.7%), proline content (124.74 µg g-1), catalase enzyme activity (22.84 units ml-1), and peroxidase enzyme activity (28.42 units ml-1). The water stress treatment S1 excelled in giving the highest values for total chlorophyll content in leaves (1.842 mg g-1), relative water content (60.9%), proline content (144.38 µg g-1), catalase enzyme activity (29.69 units ml-1), and peroxidase enzyme activity (34.07 units ml-1). The interaction between water stress level S1 and GB4 concentration resulted in the highest rates for total chlorophyll content in leaves (1.930 mg g-1), relative water content (67.2%), proline content (186.30 µg g-1), catalase enzyme activity (35.13 units ml-1), and peroxidase enzyme activity (35.19 units ml-1).

The current study was performed on a 6-year-old "Florida" peach cultivar (Prunus persica) during 2022 and 2023 respectively. Twenty-four peach trees uniformly were selected and sprayed two times at the beginning of pit starts hardening and at the end of phase two of fruit growth with the following treatments: the control, glycine betaine at 400 mg l-1, potassium silicate at 200 mg l-1, potassium silicate at 400 mg l-1, potassium silicate at 200 mg l-1 + glycine betaine at 400 mg l-1, potassium silicate at 400 mg l-1 + glycine betaine at 400 mg l-1, proline at 400 mg l-1 and potassium silicate at 200 mg l-1 + proline at 400 mg l-1. The results indicated that both treatments of potassium silicate at 200 mg l-1 + proline at 400 mg l-1 and potassium silicate at 400 mg l-1 + glycine betaine at 400 mg l-1 resulted in a significant increase in concentrations of anthocyanin and total carotenoid contents in the skin. Moreover, total soluble solid, vitamin C and total soluble solid / acidity were shown with high concentrations as compared with the control. Overall, the use of potassium silicate at 200 mg l-1 + proline at 400 mg l-1 or potassium silicate at 400 mg l-1 + glycine betaine at 400 mg l-1 two times is recommended. [ABSTRACT FROM AUTHOR]

Glycine betaine (GB) serves as a compatible solute crucial for stress tolerance across numerous plant species. Populus trichocarpa grows along coastal regions and often suffers from salt stress. In this study, we explored the effects of foliar spraying of GB on the growth, physicochemical indexes, gene expression, and stress tolerance of poplar under salt stress. To achieve this, poplar plants (Populus deltoides × Populus euramericana "Nanlin 895") were grown under four NaCl concentrations: 0, 50, 100, and 150 mM. Additionally, they were treated with 0, 5, 15, and 25 mM GB. The degree of effect on potted poplars was observed after 8 weeks. A GB treatment of about 15 mM significantly reduced the impact of salt stress and photosynthetic pigments and caused an improvement in the activity of the antioxidant enzymes peroxidase (POD) and superoxide dismutase (SOD). Moreover, GB-treated poplars had significantly more malonaldehyde (MDA) than the control lines. This study indicated that GB treatment reduces salt stress symptoms in poplars. This research helps to develop safe levels of endogenous GB, which will make poplars more resistant to environmental stresses. [ABSTRACT FROM AUTHOR]

Halophiles are one of the classes of extremophilic microorganisms that can flourish in environments with very high salt concentrations. In this study, fifteen bacterial strains isolated from various crop rhizospheric soils of agricultural fields along the Southwest coastline of Saurashtra, Gujarat, and identified by 16S rRNA gene sequencing as Halomonas pacifica, H. stenophila, H. salifodinae, H. binhaiensis, Oceanobacillus oncorhynchi, and Bacillus paralicheniformis were investigated for their potentiality to produce extremozymes and compatible solute. The isolates showed the production of halophilic protease, cellulase, and chitinase enzymes ranging from 6.90 to 35.38, 0.004–0.042, and 0.097–0.550 U ml−1, respectively. The production of ectoine-compatible solute ranged from 0.01 to 3.17 mg l−1. Furthermore, the investigation of the ectoine-compatible solute production at the molecular level by PCR showed the presence of the ectoine synthase gene responsible for its biosynthesis in the isolates. Besides, it also showed the presence of glycine betaine biosynthetic gene betaine aldehyde dehydrogenase in the isolates. The compatible solute production by these isolates may be linked to their ability to produce extremozymes under saline conditions, which could protect them from salt-induced denaturation, potentially enhancing their stability and activity. This correlation warrants further investigation. [ABSTRACT FROM AUTHOR]

Low nutrient availability is a key characteristic of the phyllosphere (the aerial surface of plants). Phyllospheric bacteria utilize a wide array of carbon sources generated by plant hosts. Glycine betaine (GB) is a plant-derived compound that can be metabolized by certain members of the phyllosphere microbiota. Metabolism of glycine betaine generates formaldehyde, an intermediate of methylotrophic metabolism, leading us to investigate how the ubiquitous plant colonizing bacterium Methylorubrum extorquens PA1 might metabolize GB encountered in its native environment. M. extorquens PA1 cannot utilize GB as a sole carbon source. Through suppressor mutation analysis, we show that M. extorquens PA1 encodes a conserved GB utilization pathway that can be activated by single point mutations conferring GB utilization as a carbon source. We identified the gene cluster encoding the GB catabolic enzymes and found that gene expression was induced in the presence of GB. We show that utilization of GB is conserved among representative Methylobacterium species and generates the one-carbon metabolism intermediate formaldehyde, which M. extorquens utilizes as a source of energy. Our results support a model where suppressor mutations in Mext_3745 or ftsH (Mext_4840) prevent the degradation of the dimethylglycine dehydrogenase subunit DgcB by the membrane integral protease FtsH, conferring the ability to utilize GB by either (i) restoring stable membrane topology of DgcB or (ii) decreasing FtsH protease activity, respectively. Both mutations alleviate the bottleneck at the second step of GB degradation catalyzed by DgcAB. [ABSTRACT FROM AUTHOR]

Integration of metabolites into the overall metabolic network of a cell requires careful coordination dependent upon the ultimate usage of the metabolite. Different stoichiometric needs, and thus pathway fluxes, must exist for compounds destined for diverse uses, such as carbon sources, nitrogen sources, or stress-protective agents. Herein, we expand upon our previous work that highlighted the nature of glycine betaine (GB) metabolism in Methylobacteria to examine the utilization of GB-derivative compounds dimethylglycine (DMG) and sarcosine into Methylorubrum extorquens in different metabolic capacities, including as sole nitrogen and/or carbon sources. We isolated gain-of-function mutations that allowed M. extorquens PA1 to utilize dimethylglycine as a carbon source and dimethylglycine and sarcosine as nitrogen source. Characterization of mutants demonstrated selection for variants of the AraC-like regulator Mext_3735 that confer constitutive expression of the GB metabolic gene cluster, allowing direct utilization of the downstream GB derivatives. Finally, among the distinct isolates examined, we found that catabolism of the osmoprotectant used for selection (GB or dimethylglycine) enhanced osmotic stress resistance provided in the presence of that particular osmolyte. Thus, access to the carbon and nitrogen and osmoprotective effects of GB and DMG are made readily accessible through adaptive mutations. In M. extorquens PA1, the limitations to exploiting this group of compounds appear to exist predominantly at the levels of gene regulation and functional activity, rather than being constrained by transport or toxicity. [ABSTRACT FROM AUTHOR]

Background: Green gram (Vigna radiata) also known as moong bean is an annually cultivated in East Asia, Southeast Asia and Indian subcontinent. V. radiata is very important source for the protein as in our regular diet and it proved essential amino acid such as phenylalanine, leucine, isoleucine, valine, lysine, arginine, methionine, threonine and tryptophan. Methods: Here, we studied the influence of seed endophytes on germination and development under salinity stress condition. Seeds were treated with sodium hypochlorite for 30 min under shaking condition at 100 rpm for surface sterilization and treated with 70% ethanol for 2 min and followed five times rinse with autoclaved water. Surface sterilised seeds were homogenised in autoclaved water with the help of mortal-pestle. Homogenised seed solution made serial dilution and spreaded over nutrient agar for endophytic bacterial growth. Seeds were treated with bacteriocide and fungicide to make endophytes free, followed by sown for germination at 0 mM, 50 mM, 100 mM and 150 mM NaCl concentration. Result: Endophyte free seedlings were more susceptible against salt stress over normal seedlings. Therefore endophyte free seedling shoot and root biomass was 23.5% and 65.7% lower than control seedling biomass at 0mM salt respectively, while root length was 70% lower than control seedling root at 0mM salt concentration. Proline content in shoot and root observed an increase with increase of salt concentration. At 0 mM salt, proline content was 0.00782±0.00043 and 0.00648±0.00017 (µmol/mg) in root of normal and endophyte free seedling respectively, while in shoot, it was non-significant difference. Glycine betaine content found to be increasing upto 100 mM, followed by decreasing at 150 mM in both root and shoot tissue. Glycine betaine content in endophyte free and control seedling shoot was 74.2±2.5 and 96.0±2.73 (µg/200 mg) respectively at 100 mM salt concentration. This result suggests, not only heritable genomic DNA but also endophytes associated with seed are very much important for the seedling growth and development which is also finally helps to combat abiotic stress situation. [ABSTRACT FROM AUTHOR]

In nature, plants constantly fight against the negative effects of biotic and abiotic stress factors. Salinity encountered in agricultural areas in the world and in our country is one of the most important factors that negatively affects sustainable agriculture. This study was carried out to investigate the effects of Gibberellic Acid (GA3) and Glycine Betaine (GB) applied as pre-treatment to sunflower seeds under salt stress conditions on germination and seedling development. In the experiment, the seeds were pre-treated with four different concentrations of GA3 and GB (0, 15, 30, 45 mg/l) before planting, and then four different salt (Na+Cl-) concentrations (0, 6, 9, 12 dS/m) was put into salt stress application. The experiment was set up with 3 replications according to the Randomized Plot Factorial Trial Design. In the study, germination rate, germination power, seedling length, root length, seedling fresh weight, root fresh weight characteristics and enzyme activities such as CAT, SOD and POD were examined. In the experiment, parallel to the increase in salinity stress, decreases in germination rate and germination power and negative effects on other seedling characteristics were observed. According to the results obtained, positive results were observed for germination and seedling characteristics at 6 dS/m salt stress in 30 and 45 mg/l GB and GA3 applications. As a result, it was concluded that Glycine Betaine applications to sunflower seeds as an alternative to plant regulator groups under salt stress conditions will be beneficial in production. [ABSTRACT FROM AUTHOR]

To evaluate the effects of Glycine Betaine, Zinc, and Boron elements on the yield and nutritional status of rainfed Cicer arietinum, a factorial experiment, was conducted during the 2019 and 2020 cropping years in Mahabad city. The experiment followed a randomized complete block design with three replications. The experimental factors included soil application of zinc sulfate at two levels (40 kg/ha and no zinc application), foliar application of boron at three levels (no use, before, and after flowering with 3 kg per 1000 L of water), and foliar application of Glycine Betaine at three levels (no use, flowering, and after flowering with 1.88 g/L). The results indicated that the year significantly affected grain yield, biological yield, and uptake of boron and zinc. The treatments involving boron and Glycine Betaine showed an increasing effect on plant height, total chlorophyll, soluble sugar, Glycine Betaine, number of pods per plant, number of seeds per plant, 100-seed weight, grain yield, biological yield, nitrogen percentage, boron concentration, and grain protein percentage. The highest grain yield (1549.15 kg. ha−1) in the treatment without zinc application and with simultaneous application of boron and Glycine Betaine after flowering resulted in a 34.58% increase compared to the control. The foliar application of Glycine Betaine and boron in the pre-and post-flowering stages and boron in the post-flowering stage resulted in the highest grain nitrogen uptake at 60.2%. Also, the result showed that no Glycine Betaine and boron application before flowering exhibited the highest soluble sugar content. [ABSTRACT FROM AUTHOR]

Biochar (BC) and plant growth-promoting microbes (PGPR) could represent a suitable agronomical strategy to mitigate the impacts of drought in arid agro-environmental conditions. However, there is currently little understanding of the synergistic benefit of combining BC and PGPR to increase drought tolerance in oilseeds. In this study, the physiological response of two water-stressed canola (Brassica napus L.) plants subjected to the application of BC obtained from waste wood of Morus alba applied solely or in combination with PGPR strains (Pseudomonas sp.) was evaluated. The experiment consists of two genotypes and nine treatments [(C-Control, T1-15 days drought (15DD), T2-30 days drought (30DD), T3-15 days of drought + PG (15DD + PG), T4-30 days of drought + PG (30DD + PG), T5-15 days drought + biochar (15DD + BC), T6-30 days drought + biochar (30DD + BC), T7-15 days drought + biochar + PG (15DD + BC + PG), T8-30 days drought + biochar + PG (30DD + BC + PG)]. Drought stress decreased emergence energy (EE), leaf area index (LAI), leaf area ratio (LAR), root shoot ratio (RSR), moisture content of leaves (MCL), percent moisture content (%MC), moisture content of shoot (MCS) and moisture content of root (MCR), and relative water content (RWC) in both varieties of Brassica napus L., which in contrast, it is increased by the collective application of both biochar and PGPR. In both varieties, N, P, K, Mg, and Ca concentrations were highest in all the biochar and PGPRs separate and combined treatments, while lowest in 15 and 30 days drought treatments. Osmolyte contents like Glycine betaine (GB) and sugar remarkably increased in the stress condition and then reduced due to the synergistic application of biochar and PGPR. Drought stress has a repressive effect on the antioxidant enzymatic system like Peroxidase (POD), Superoxide dismutase (SOD), and glutathione reductase (GR) as well as total flavonoids, phenolics, and protein content. The antioxidant enzymes and phenolic compounds were dramatically increased by the combined action of biochar and PGPRs. A significant increase in EE, LAR, RSR, and RWC under 15 and 30 days drought conditions, evidently highlighting the synergistic effect of BC and PGPR. The results conclude a substantial and positive effect of the combined use of BC and PGPR strains on canola's response to induced drought stress, by regulating the physiological, biochemical, and agronomic traits of the plants. [ABSTRACT FROM AUTHOR]

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Abstract Background Glycyrrhiza uralensis Fisch., a valuable medicinal plant, shows contrasting salt tolerance between seedlings and perennial individuals, and salt tolerance at seedling stage is very weak. Understanding this difference is crucial for optimizing cultivation practices and maximizing the plant’s economic potential. Salt stress resistance at the seedling stage is the key to the cultivation of the plant using salinized land. This study investigated the physiological mechanism of the application of glycine betaine (0, 10, 20, 40, 80 mM) to seedling stages of G. uralensis under salt stress (160 mM NaCl). Results G. uralensis seedlings’ growth was severely inhibited under NaCl stress conditions, but the addition of GB effectively mitigated its effects, with 20 mM GB had showing most significant alleviating effect. The application of 20 mM GB under NaCl stress conditions significantly increased total root length (80.38%), total root surface area (93.28%), and total root volume (175.61%), and significantly increased the GB content in its roots, stems, and leaves by 36.88%, 107.05%, and 21.63%, respectively. The activity of betaine aldehyde dehydrogenase 2 (BADH2) was increased by 74.10%, 249.38%, and 150.60%, respectively. The 20 mM GB-addition treatment significantly increased content of osmoregulatory substances (the contents of soluble protein, soluble sugar and proline increased by 7.05%, 70.52% and 661.06% in roots, and also increased by 30.74%, 47.11% and 26.88% in leaves, respectively.). Furthermore, it markedly enhanced the activity of antioxidant enzymes and the content of antioxidants (SOD, CAT, POD, APX and activities and ASA contents were elevated by 59.55%, 413.07%, 225.91%, 300.00% and 73.33% in the root, and increased by 877.51%, 359.89%, 199.15%, 144.35%, and 108.11% in leaves, respectively.), and obviously promoted salt secretion capacity of the leaves, which especially promoted the secretion of Na+ (1.37 times). Conclusions In summary, the exogenous addition of GB significantly enhances the salt tolerance of G. uralensis seedlings, promoting osmoregulatory substances, antioxidant enzyme activities, excess salt discharge especially the significant promotion of the secretion of Na+Future studies should aim to elucidate the molecular mechanisms that operate when GB regulates saline stress tolerance.

Cold is one of the abiotic environmental factors that severely affect plant metabolism. It causes changes in the fluidity of biological membranes, induces oxidative and osmotic stress, photoinhibition, reduces photosynthetic rates and slows down numerous metabolic enzyme activities. Some effects of cold overlap with drought response processes. Drought itself has a dualistic effect on plants. Severe drought stress is detrimental, while a mild preceding drought may prepare the otherwise sensitive maize to cope with cold. This study focused on the effects of mild drought on photosynthesis, sugar and amino acid metabolism at low temperature. Maize (Zea mays L.) plants were drought-hardened (15±5% relative soil moisture) between stages V4 and V6 at 25°C for 10 days and then subjected to cold treatmet at 10°C for 2 weeks at two light levels (PPFD=450 and 150 µmol m-2 s-1). The control population was watered daily (35±5% soil moisture), and in completely dried pots, 5±3% soil moisture was measured. The present results confirmed that photosynthetic performance and glutamine biosynthesis were positively affected by drought under both light intensities. Plants exposed to combined cold and moderate drought stress had a higher dry weight than those exposed to cold stress alone. The metabolism of several sugars, organic acids and amino acids was maintained by mild drought acclimation. The cold protective DHN2-like dehydrin gene was induced by moderate drought treatment, which may have contributed to the drought-induced higher tolerance to low temperature. However, cold stress markers were lower in low light than in normal growth light under drought acclimation, suggesting that drought-induced stress defense may require a certain level of light.

Nickel is an essential micronutrient for plant growth and development. However, in excessive amounts caused by accidental pollution of soils, this heavy metal is toxic to plants. Although silicon is a non-essential nutrient, it accumulates in most monocots, particularly the vital crop maize (corn, Zea mays). In fact, this metalloid mineral can alleviate the toxicity of heavy metals, though the mechanism is not entirely clear yet. Herein, we measured proteome, gene expression, enzyme activities, and selected sugars to investigate such effect thoroughly. Deep proteomic analysis revealed a minor impact of 100 µM Ni, 2.5 mM Si, or their combination on roots in 12-day-old hydroponically grown maize seedlings upon 9 days of exposure. Nonetheless, we suggested plausible mechanisms of Si mitigation of excessive Ni: Chelation by metallothioneins and phytochelatins, detoxification by glycine betaine pathway, and restructuring of plasma membrane transporters. Higher activity of glutathione S-transferase confirmed its plausible involvement in reducing Ni toxicity in combined treatment. Accumulation of sucrose synthase and corresponding soluble sugars in Ni and combined treatment implied high energy requirements both during heavy metal stress and its mitigation. Expression analysis of genes coding a few differentially accumulated proteins failed to reveal concordant changes, indicating posttranscriptional regulation. Proposed mitigation mechanisms should be functionally validated in follow-up studies.

Osmolytes proline (Pro) and glycine betaine (GB) have been reported to impart tolerance against salinity stress in many plants. However, there is no report available on the combined application of Pro and GB to mitigate salinity-induced growth inhibition in maize. Consequently, the goal of the current study is to assess Pro's and GB's potential as priming and exogenous agents in maize under salt stress. Therefore, the present study was conducted using a petri dish and hydroponic pot experiment to evaluate the morpho-physiological and biochemical characteristics of maize plants subjected to salt stress, with the addition of Pro and GB. The seeds of maize were germinated under 20 mM of each Pro or GB, with or without 120 mM salinity stress. The findings demonstrated that salt stress lessened the final germination percentage (FGP) (52.9 %), photosynthetic pigments (40.0 %), relative water content (RWC) (20.2 %), stomatal size (59.3 %), and leaf and root K+/Na+ ratios of maize seedlings compared to control. In addition, compared to the control, higher levels of malondialdehyde (MDA) (24.2 %) and hydrogen peroxide (H2O2) (25.7 %) were observed, whereas lower levels of catalase (CAT) (43.8 %) and peroxidase (POX) (30.4 %) were noted. The priming with Pro, GB, Pro+GB significantly increased FGP, germination index (GI), shoot-root biomass, seed vigor index (SVI), and reduced mean germination time (MGT) under salt stress. Foliar application of Pro, GB, or Pro+GB resulted in a significant increment in chlorophyll contents, RWC, K+ absorption, and stomatal size under salt stress. Furthermore, supplementing with Pro, GB, or Pro+GB reduced the accumulation of H2O2 (24.0, 23.3, and 31.1 %, respectively) and MDA (22.8, 17.2, and 32.1 %, respectively) caused by salt and augmented the levels of CAT (33.3, 22.8, and 45.2 %, respectively) and POX (36.4, 23.5, and 47.2 %, respectively) in the leaves. Taken together, the current study's findings indicate that combining Pro and GB is one of the most effective techniques for improving the salinity-tolerant seed germination and seedling traits of maize plants. Consequently, this study recommends that Pro and GB can be used as seed priming and exogenous agents to help maize grow faster in salt-stress situations.

Climate change will pose a challenge for the winemaking sector worldwide, bringing progressively drier and warmer conditions and increasing the frequency and intensity of weather extremes. The short-term adaptation strategy of applying biostimulants through foliar application serves as a crucial measure in mitigating the detrimental effects of environmental stresses on grapevine yield and berry quality. The aim of this study was to evaluate the effect of foliar application of a seaweed-based biostimulant (A. nodosum—ANE) and glycine betaine (GB) on berry quality, phenolic compounds, and antioxidant activity and to elucidate their action on the secondary metabolism. A trial was installed in a commercial vineyard (cv. "Touriga Franca") in the Cima Corgo (Upper Corgo) sub-region of the Douro Demarcated Region, Portugal. A total of four foliar sprayings were performed during the growing season: at flowering, pea size, bunch closer, and veraison. There was a positive effect of GB in the berry quality traits. Both ANE and GB increased the synthesis of anthocyanins and other phenolics in berries and influenced the expression of genes related to the synthesis and transport of anthocyanins (CHS, F3H, UFGT, and GST). So, they have the potential to act as elicitors of the secondary metabolism, leading to improved grape quality, and also to set the foundation for sustainable agricultural practices in the long run. [ABSTRACT FROM AUTHOR]

Plants are often exposed to non-ideal conditions during their growth. The toxicity of heavy metals as abiotic stressors is a significant concern due to their harmful effects on plants. Glycine betaine (GB) is a potent compatible solute that helps plants resist abiotic stresses and plays a crucial role in alleviating them. This study aimed to determine the effective role of glycine betaine (0.5 and 1 mM) as a foliar treatment in sugar beet plants to cope with the toxicity of cadmium (50 mg/kg soil) and lead (100 mg/kg soil). The application of lead (Pb) and cadmium (Cd) in cultivation soil noticeably suppressed morphological growth attributes, such as chlorophylls, carotenoids, sugars, and proteins. At the same time, the aforementioned levels of heavy metals significantly increased the levels of non-enzymatic antioxidants (phenolics and proline) and enzymatic antioxidants (peroxidase, superoxide dismutase, polyphenol oxidase, and catalase) in the root and shoot tissues of sugar beet plants. In contrast, the use of glycine betaine as foliar treatment at 0.5 and 1 mM alleviated the adverse impacts of cadmium and lead by promoting the aforementioned attributes. Furthermore, the application of 1 mM GB was more effective in increasing the contents of phenolics in root by approximately 16% and 29%, phenolics in shoot by about 25% and 10%, peroxidase activity by about 82% and 116%, superoxide dismutase activity by about 56% and 47%, polyphenol oxidase activity by about 9% and 36%, catalase activity by about 19% and 25%, in cadmium- and lead-stressed plants, respectively. Additionally, it reduced the levels of proline in sugar beet tissues. Overall, the application of glycine betaine has the efficacy to counteract the adverse impacts of cadmium and lead toxicity on sugar beet plants by enhancing the metabolic indices as well as the non-enzymatic and enzymatic antioxidant activities. [ABSTRACT FROM AUTHOR]

Extreme weather events, including drought, have occurred worldwide with increasing frequency and severity in recent years. Drought stress is the main limiting factor for agricultural development in many regions, including tobacco—an important economic crop and a model plant for scientific research. As it is adapted to the tropics, tobacco is highly susceptible to drought stress, with resultant decreases in yield and quality. Glycine betaine (GB) is an osmoregulatory substance that can enhance plant resistance to various abiotic stresses. Here, we investigate the protective mechanism of genetically engineered glycine betaine (GB) on tobacco photosynthesis under drought stress induced by 30% PEG-6000. This study used transgenic tobacco (T) accumulating GB and wild-type tobacco (WT) to investigate the protective effects conferred by the genetic engineering of GB synthesis on tobacco photosynthesis under drought stress (induced by 30% PEG-6000). The results showed that the net photosynthetic rate of the tobacco plants significantly decreased under drought stress, and the degree of decrease was significantly lower in the T line than in the WT line. GB accumulation improved the resistance of photosynthesis to drought stress. Furthermore, under drought stress, the photosynthesis improvement in the T line was related to the accumulation of GB, leading to maintenance of the water status, the promotion of osmotic regulation, and an enhancement in antioxidant enzyme activities, which reduced membrane peroxidation and thereby increased the thylakoid membrane's protein content and function, especially the photosystem II (PSII) function. The results provide a theoretical basis for further research on genetic engineering related to GB synthesis and the field application of exogenous GB. [ABSTRACT FROM AUTHOR]

Objective: Methicillin-resistant Staphylococcus aureus (MRSA) is a clinically common and has a high mortality rate pathogen, as well as a bacterium that causes infection through food. To combat with pathogens, it is commonly preferred to create osmotic stress in their environment but S. aureus is able to synthesize some osmoprotectant substances such as betaine. There is limited literature about the synthesis pathways and gene expressions of these substances. This study aims to search the metabolic pathways of osmoprotectan production of S. aureus by comparing the bacterial behaviour with the expression of genes responsible for betaine. Methods: In the current study, different concentrations of NaCl and KCl salts (0.5, 1.0, 1.5, 2.0 and 3.0 M) were applied to Staphylococcus aureus ATCC 43300, changes in the number of viable cells of the bacteria were monitored and associated with osmoprotectant production. Bacterial numbers treated with salt were counted by culturel and spectrophotometric methods and viability graphs were created. Simultaneously, metabolic pathways under stress conditions were determined by monitoring the expression of genes responsible for betaine in RT-PCR. Results: When the growth curve of the bacterium is examined in NaCl or KCl salt stress, it was observed that the bacteria exited the logarithmic phase and was more affected by the stress conditions, especially at 12-24 time interval which is critical in the development of bacteria. The most notable results in the RT-PCR trials of the study were obtained when 1.5 M NaCl was present in the growth media at 36th hour of incubation. Under these conditions, a significant decrease of (-2.37-fold) in the betA gene was observed. Contrary to this result, 2.57-fold increase in the betA gene and 3.25-fold increase in the betB-gbsA gene was observed when 2 M KCl was present in the medium at 48th hour of incubation. Conclusion: During the 48-hour incubation period in which the bacterial growth was followed, it was observed that the bacteria exhibited a fluctuating growth curve against the salt stress and exhibited a different behavior than expected in the growth kinetics. [ABSTRACT FROM AUTHOR]

Low temperature is a type of abiotic stress affecting the tomato (Solanum lycopersicum) growth. Understanding the mechanisms and utilization of exogenous substances underlying plant tolerance to cold stress would lay the foundation for improving temperature resilience in this important crop. Our study is aiming to investigate the effect of exogenous glycine betaine (GB) on tomato seedlings to increase tolerance to low temperatures. By treating tomato seedlings with exogenous GB under low temperature stress, we found that 30 mmol/L exogenous GB can significantly improve the cold tolerance of tomato seedlings. Exogenous GB can influence the enzyme activity of antioxidant defense system and ROS levels in tomato leaves. The seedlings with GB treatment presented higher Fv/Fm value and photochemical activity under cold stress compared with the control. Moreover, analysis of high-throughput plant phenotyping of tomato seedlings also supported that exogenous GB can protect the photosynthetic system of tomato seedlings under cold stress. In addition, we proved that exogenous GB significantly increased the content of endogenous abscisic acid (ABA) and decreased endogenous gibberellin (GA) levels, which protected tomatoes from low temperatures. Meanwhile, transcriptional analysis showed that GB regulated the expression of genes involved in antioxidant capacity, calcium signaling, photosynthesis activity, energy metabolism-related and low temperature pathway-related genes in tomato plants. In conclusion, our findings indicated that exogenous GB, as a cryoprotectant, can enhance plant tolerance to low temperature by improving the antioxidant system, photosynthetic system, hormone signaling, and cold response pathway and so on. [ABSTRACT FROM AUTHOR]

Halophytes adapt to salinity using different biochemical response mechanisms. Temporal measurements of biochemical parameters over a period of exposure to salinity may clarify the patterns and kinetics of stress responses in halophytes. This study aimed to evaluate short-term temporal changes in shoot biomass and several biochemical variables, including the contents of photosynthetic pigments, ions (Na+, K+, Ca2+, and Mg2+), osmolytes (proline and glycine betaine), oxidative stress markers (H2O2 and malondialdehyde), and antioxidant enzymes (superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase) activities of three halophytic Salicornia species (S. persica, S. europaea, and S. bigelovii) in response to non-saline, moderate (300 mM NaCl), and high (500 mM NaCl) salinity treatments at three sampling times. Salicornia plants showed maximum shoot biomass under moderate salinity conditions. The results indicated that high Na+ accumulation in the shoots, coupled with the relative retention of K+ and Ca2+ under salt stress conditions, contributed significantly to ionic and osmotic balance and salinity tolerance in the tested Salicornia species. Glycine betaine accumulation, both constitutive and salt-induced, also seems to play a crucial role in osmotic adjustment in Salicornia plants subjected to salinity treatments. Salicornia species possess an efficient antioxidant enzyme system that largely relies on the ascorbate peroxidase and peroxidase activities to partly counteract salt-induced oxidative stress. The results also revealed that S. persica exhibited higher salinity tolerance than S. europaea and S. bigelovii, as shown by better plant growth under moderate and high salinity. This higher tolerance was associated with higher peroxidase activities and increased glycine betaine and proline accumulation in S. persica. Taking all the data together, this study allowed the identification of the biochemical mechanisms contributing significantly to salinity tolerance of Salicornia through the maintenance of ion and osmotic homeostasis and protection against oxidative stress. [ABSTRACT FROM AUTHOR]

The use of biostimulants is becoming a useful tool for increasing crop productivity while enhancing nutritional quality. However, new studies are necessary to confirm that the joint application of different types of biostimulants, together with bioactive compounds, is effective and not harmful to plants. This study examined the impact of applying the biostimulant Green Leaves, comprising Macrocystis algae extract and containing a mixture of amino acids, corn steep liquor extract, calcium, and the bioactive compound glycine betaine. The effect of applying two different doses (3 and 5 mL L−1) of this biostimulant was evaluated on lettuce plants, and growth and quality parameters were analyzed along with photosynthetic efficiency, nutritional status, and nutrient efficiency parameters. The application of Green Leaves improved plant weight (25%) and leaf area and enhanced the photosynthetic rate, the accumulation of soluble sugars and proteins, and the agronomic efficiency of all essential nutrients. The 3 mL L−1 dose improved the nutritional quality of lettuce plants, improving the concentration of phenolic compounds and ascorbate and the antioxidant capacity and reducing NO3− accumulation. The 5 mL L−1 dose improved the absorption of most nutrients, especially N, which reduced the need for fertilizers, thus reducing costs and environmental impact. In short, the Green Leaves product has been identified as a useful product for obtaining higher yield and better quality. [ABSTRACT FROM AUTHOR]

Roses (genus Rosa), renowned for their economic significance and aesthetic appeal, face multifaceted challenges in cultivation due to biotic and abiotic stressors. To address these challenges, this study explores the role of osmolytes, particularly polyamines, proline and glycine betaine, as well as antioxidant capacities and condensed tannins, in enhancing stress tolerance in roses. Despite the genetic diversity inherent in roses, the metabolic aspect of stress tolerance has been underexplored in breeding programs. This paper investigates the intraspecific variability among 22 rose cultivars, focusing on osmolyte content (proline and glycine betaine), individual polyamines (putrescine, spermine and spermidine), as well as antioxidant activities, measuring radical scavenging capacity against 2,2′-azinobis(3-ethylbenzothiozoline-6-sulfonic acid (ABTS•+) and NO• radicals. Employing a targeted metabolomic approach, we quantified the levels of individual polyamines in both the petals and leaves of rose cultivars. This was achieved through high-performance liquid chromatography coupled with fluorescent detection following a derivatization pretreatment process. Within the evaluated cultivars, "Unique Aroma", "Andre Rieu", "Aroma 3", "Frayla Marija" and "Trendy Fashion" stood out for their significantly elevated levels of total foliar polyamines. The predominant polyamine detected at both petal and leaf levels was putrescine, with concentrations ranging from 335.81 ("Zora Frayla") to 2063.81 nmol g−1 DW ("Unique Aroma") at the leaf level. Following putrescine, foliar spermidine levels varied from 245.08 ("Olivera Frayla") to 1527.16 nmol g−1 DW ("Andre Rieu"). Regarding antioxidant capacity, the leaf extracts of rose cultivars "Zora Frayla" and "Natalija Frayla" were prominent by showing 68.08 and 59.24 mmol Trolox equivalents (TE) g−1 DW, respectively. The results highlight the intricate biochemical variability across rose cultivars and show that osmolytes, such as glycine betaine, proline and polyamines, and other biochemical markers can be used as reliable criteria for the selection of rose cultivars that are more resilient to biotic stress factors, especially powdery and downy mildew. Bridging fundamental research with practical applications, this study aims to contribute to the development of stress-tolerant rose cultivars adaptable to dynamic environmental conditions. [ABSTRACT FROM AUTHOR]

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Introduction: Green house studying especially for salinity stress needs suitable medium. It is necessary to determine suitable medium in greenhouse studies for screening germplasm, which is easily available, stable in terms of electrical conductivity and cost-effective. Soil, and Perlite are common mediums which are used in green house researches generally, but there weren't enough reports for study hydroponic system for screening sugar beet germplasm. Drought and salinity stress happens at the same time in most regions of Iran and because of similar tolerance mechanisms for these stresses, drought tolerant germplasm could be used in screening for salinity.so the goal of this project was to evaluate different medium especially hydroponic to screening sugar beet drought tolerance genotype in salinity stress. Materials and methods: The project was conducted in two experiments: (a) A factorial experiment based on completely randomized design with four replications was conducted in SBSI research greenhouse. The first factor was three planting media in combination with nutrition solution as follows: 1) loamy soil with about 5% organic matter, 2) perlite with Hoagland solution, 3) hydroponic environment with Hoagland solution. The second factor consisted of two levels of salinity including normal and salinity (16 dS m-1) treatments and the third factor consisted of two sensitive and tolerant genotypes. (b) 17 selected genotypes were investigated in greenhouse with perlite medium under control and salinity 16 dS m-1 in factorial experiment based on completely randomized design with four replications. Different quantitative and qualitative traits such as root. Shoot and total dry weights, K/Na, Soluble carbohydrates, glycine betaine were measured in both experiments and statistical analysis were done by MSTATC and SPSS and mean were compared in Duncan multiple range test at (α=0.05). Results and discussion: Cross effects of medium and salinity were significant on total and shoot dry weights, P, K/Na. Cross effects of medium, salinity and genotypes were significant on most of the traits. Crop yields under salinity stress were less in soil in comparison to other mediums, also salinity had significant effect on soil EC and Na (P≤0.01), soil and perlite were salinized respectively 6 and 2 times in comparison to normal condition. Which shows that soil is not stable medium for salinity study in green house. The highest yield (3.31 g p-1) was obtained from hydroponic. Yields achieved from hydroponic and perlite mediums were similar under salinity, but water consumption was more in hydroponic than perlite. In establishment stage, the total dry weight, soluble carbohydrates, glycine betaine and K/Na ratio were suitable for selection of sugar beet genotypes under salinity stress. According to all measurements, the clustering in establishment stages and Stress Tolerance Index (STI), HSF-91018, HSF-91040, HSF-92870, HSF-92881, HSF-92884, genotypes were selected as tolerant genotypes as controls. Conclusion: Sensitive and tolerant genotypes were not distinguished well in hydroponic medium, which related to its potential and was mentioned in other reports. Hydroponic and perlite were in the same group for different traits especially they became less salty than soil but hydroponic system is not useful for root beet but it would be suitable for forage beet because biomass production is more in this condition. Also, soil is not suitable medium for study salinity researches because it became seven times more salty than normal condition. As a result perlite is the best medium for salinity studies in sugar beet because it becomes less salty, it has low weight and cost and has less side effects on environment. According to all measurements, the clustering in germination and establishment stages and Stress Tolerance Index (STI), HSF-91018, HSF-91040, HSF-92870, HSF-92881, HSF-92884, genotypes were selected as tolerant genotypes as controls. [ABSTRACT FROM AUTHOR]

Maize production and productivity are affected by drought stress in tropical and subtropical ecologies, as the majority of the area under maize cultivation in these ecologies is rain-fed. The present investigation was conducted to study the physiological and biochemical effects of 24-Epibrassinolide (EBR) as a plant hormone on drought tolerance in maize. Two maize hybrids, Vivek hybrid 9 and Bio 9637, were grown under three different conditions: (i) irrigated, (ii) drought, and (iii) drought+EBR. A total of 2 weeks before the anthesis, irrigation was discontinued to produce a drought-like condition. In the drought+EBR treatment group, irrigation was also stopped, and in addition, EBR was applied as a foliar spray on the same day in the drought plots. It was observed that drought had a major influence on the photosynthesis rate, membrane stability index, leaf area index, relative water content, and leaf water potential; this effect was more pronounced in Bio 9637. Conversely, the activities of antioxidant enzymes such as catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD) increased in both hybrids under drought conditions. Specifically, Vivek hybrid 9 showed 74% higher CAT activity under drought conditions as compared to the control. Additionally, EBR application further enhanced the activity of this enzyme by 23% compared to plants under drought conditions. Both hybrids experienced a significant reduction in plant girth due to drought stress. However, it was found that exogenously applying EBR reduced the detrimental effects of drought stress on the plant, and this effect was more pronounced in Bio 9637. In fact, Bio 9637 treated with EBR showed an 86% increase in proline content and a 70% increase in glycine betaine content compared to untreated plants under drought conditions. Taken together, our results suggested EBR enhanced tolerance to drought in maize hybrids. Hence, pre-anthesis foliar application of EBR might partly overcome the adverse effects of flowering stage drought in maize. [ABSTRACT FROM AUTHOR]

High salinity inhibits microbial activity in the bioremediation of saline wastewater. To alleviate osmotic stress, glycine betaine (GB), an osmoprotectant, is added to enhance the secretion of extracellular polymeric substances (EPS). These EPS are pivotal in withstanding environmental stressors, yet the intricate interplay between GB supplementation and microbial responses through EPS modifications—encompassing composition, molecular architecture, and electrochemical features—remains elusive in hypersaline conditions. Here we show microbial strategies for salinity endurance by investigating the impact of GB on the dynamic alterations of EPS properties. Our findings reveal that GB supplementation at 3.5% salinity elevates the total EPS (T-EPS) content from 12.50 ± 0.05 to 24.58 ± 0.96 mg per g dry cell weight. The observed shift in zeta potential from −28.95 to −6.25 mV at 0% and 3.5% salinity, respectively, with GB treatment, indicates a reduction in electrostatic repulsion and compaction. Notably, the EPS protein secondary structure transition from β-sheet to α-helix, with GB addition, signifies a more compact protein configuration, less susceptible to salinity fluctuations. Electrochemical analyses, including cyclic voltammetry (CV) and differential pulse voltammetry (DPV), reveal GB's role in promoting the release of exogenous electron shuttles, such as flavins and c-type cytochromes (c-Cyts). The enhancement in DPV peak areas (QDPV) with GB addition implies an increase in available extracellular electron transfer sites. This investigation advances our comprehension of microbial adaptation mechanisms to salinity through EPS modifications facilitated by GB in saline habitats.

Phosphatidylcholine (PtdCho) is an unusual membrane phospholipid present in some endosymbiotic and intracellular pathogenic prokaryotes. ‘Candidatus Liberibacter asiaticus’ (CLas) is a phloem-limited, uncultured, fastidious α-Proteobacterium associated with the devastating citrus “greening” disease (huanglongbing). Phylogenetically related but nonpathogenic Liberibacter crescens (Lcr) was used as a culturable surrogate to examine PtdCho biosynthesis in pathogenic CLas. Genes encoding key enzymes for two alternative PtdCho biosynthetic routes are present in the Lcr genome: the one-step cytidine diphosphate (CDP)-choline (pcs-encoding phosphatidylcholine synthase) and the three-step methyl-transferase pathway (pmt-encoding phospholipid N-methyltransferase). However, only the CDP-choline pathway genes for incorporating exogenous Cho were identified in the CLas genome. Exogenous Cho enhanced growth and alleviated osmotic stress in wild-type Lcr and in the pmt insertion mutant strains when cultured in a sugar-rich medium. Quantitative RT-PCR analyses confirmed active uptake and condensation of nutritional Cho into PtdCho by CLas in both its plant host and psyllid vector. CLas-infected grapefruit leaves showed transcriptional activation of Cho biosynthesis genes and 2.8-fold higher levels of Cho. In plant cells, the compatible osmolyte glycine-betaine (GlyBet) is also derived from Cho. Expression of GlyBet biosynthesis genes and the GlyBet content were similar in both CLas-infected and healthy leaf tissue. The data presented here suggest that CLas likely exploits the Cho biosynthetic pathway in citrus hosts to expand the nutritional Cho pool. [Figure: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Salt stress is a major abiotic factor that negatively impacts the growth, performance, and secondary metabolite production in pepper (Capsicum annuum L.) plants. Brassinosteroids (BRs) play a crucial role in enhancing plant tolerance to abiotic stress, yet their potential in mitigating salt stress in pepper plants, particularly by promoting sugar and glycine betaine accumulation, remains underexplored. In this study, we investigated the effects of the foliar application of 2,4-epibrassinolide (EBR) on salt-stressed pepper seedlings. Our findings revealed that EBR treatment significantly increased the levels of proline, sugar, and glycine betaine under salt stress compared to untreated controls. Moreover, EBR enhanced the antioxidant defense mechanisms in pepper seedlings by increasing sugar and glycine betaine levels, which contributed to the reduction of reactive oxygen species (ROS) and malondialdehyde (MDA) accumulation.

Sweet cherries are among consumers’ preferred fresh fruits, known for their attractive organoleptic properties and high nutritional value. Agronomical practices, which are now shifting to more environmentally sustainable options, can influence several key quality traits of sweet cherries. In this context, reducing conventional agrochemicals and increasing the application of preharvest biostimulants has emerged as an innovative strategy. This approach can not only enhance cherry production and quality but also ensure the economic and environmental sustainability of the cherry supply chain. Hence, this work is aimed at studying the effect of the application of two concentrations of glycine betaine (GB) and Ecklonia maxima-based (EM) biostimulants, and their combination, in two cultivars of sweet cherry: the early-maturing ‘Early Bigi’ and the late-maturing ‘Lapins’, both grafted onto SL-64 rootstock. Evaluated parameters included fruit weight and dimensions, color, firmness, total soluble solids (TSS), titratable acidity (TA), phenolic and anthocyanin contents, and sensory profile. Key findings highlight that, with a few exceptions, biostimulant treatments had a positive impact on the studied parameters, although the responses varied between cultivars. For instance, fruit size increased by 13.41% in ‘Early Bigi’ and 47.20% in ‘Lapins’. Additionally, reduced color values, coupled with higher TSS/TA ratios, indicate advanced fruit maturation, which could allow for an earlier harvest. The total phenolic content rose by 56.88% in ‘Early Bigi’ and 30.24% in ‘Lapins’, while anthocyanin levels surged by 88.28% and 36.10%, respectively. Fruit firmness also improved following biostimulant application. Sensory analysis further revealed enhancements in key descriptors such as “overall aspect”, “firmness”, and “cherry flavor”, underscoring the beneficial effects of these treatments. These combined results indicate that the preharvest application of glycine betaine or Ecklonia maxima-based (EM) biostimulants significantly improves key quality traits of sweet cherries. This approach offers benefits not only from a commercial perspective but also for the sweet cherry supply chain sustainability by reducing the application of chemical-based products and replacing them with ecofriendly substances while enhancing the quality of the fruit.

[Objective] Betaine aldehyde dehydrogenase (BADH) is one of the key enzymes involved in glycine betaine synthesis and plays an important role in plant response to abiotic stress. [Method] To explore the biological function and gene expression pattern of BvBADH gene family members in sugar beet (Beta vulgaris), the physicochemical properties of protein, phylogenetic evolution, gene structure, chromosome localization, conserved motif, protein structure, and promoter cis-acting regulatory elements of BvBADHs were analyzed by bioinformatics method, and their expression patterns under salt stress were investigated by RT-qPCR. [Result] A total of 9 BvBADH gene family members were identified. They contained 9-15 exons and 8-14 introns, the average amino acid number was 516, the average molecular weight was 55.84 kD, and the isoelectric point was 5.24-6.98. Phylogenetic analysis found that BADHs of higher plants were divided into three clusters, namely Clusters I, II, and III, among which Cluster III members can be further divided into two subgroups, including Cluster IIIa and IIIb. The members of BvBADH gene family were distributed in 3 clusters, respectively containing 3, 1, and 5 members. The promoter of the BvBADH gene mainly contained stress response elements, hormone response elements and growth and development response elements, the cis-acting regulatory element numbers of each member were 13-21. Further analysis of the expression pattern of the BvBADH genes in the sugar beet leaves showed that both 100 and 150 mmol/L NaCl significantly increased the expressions of all members of BvBADHs, but their expressions under 100 mmol/L NaCl were higher than those under 150 mmol/L NaCl. [Conclusion] The BvBADH gene family plays an important role in sugar beet's response to salt stress, it provides excellent genetic resources for the genetic improvement of crop stress tolerance in northern China. [ABSTRACT FROM AUTHOR]

The toxicity of lead (Pb) in agricultural soil is constantly increasing as a result of anthropogenic activities. Pb is one of the most phytotoxic metals in soil that accumulates in plant tissue, resulting in yield loss. It is currently becoming more popular to supplement glycine betaine (GB) for Pb-induced stress tolerance in crop plants. Currently, no report describes the use of GB as a stress mitigator for growth attributes and stress-specific biomarkers in barley plants under Pb stress conditions. Hence, the present research was designed to examine the stress-mitigating behavior of GB on various growth attributes including germination percentage, seed vigor index (SVI), radicle length, plant biomass (fresh and dry), shoot and root length, physiological attributes such as relative water content (RWC), and stress-specific biomarkers like electrolyte leakage (EL), and H2O2 content of two barley varieties viz. BH959 and BH946 at three Pb stress treatments (15 mM, 25 mM, and 35 mM), with and without GB (2 mM) supplementation in natural conditions. The present investigation showed that at the highest Pb stress (35 mM), the germination rate was reduced to zero, and the growth attributes and RWC of both barley varieties were also reduced as compared to the non-stressed plants (control) with an increase in Pb treatment. However, EL up to 70% and H2O2 content up to 30% increased with an increase in Pb stress concentration indicated by ROS accumulation, resulting in more oxidative stress. Additionally, GB application alleviated the toxic effect of Pb stress by improving the rate of germination by 33.3% and growth performance by reducing the ROS accumulation in terms of reducing stress biomarkers H2O2 by 25%, and EL by 12%. It has been revealed that the application of GB can minimize or reduce the toxic effects caused by Pb toxicity in both varieties, positively modulating plant growth performances and lowering oxidative stress. This research may provide a scientific basis for assessing Pb tolerance in barley plants and developing alternative approaches to protecting them from the severe effects of Pb toxicity. [ABSTRACT FROM AUTHOR]

The problem of water shortage worries many countries in the world because its negative impact on many economic crops. In this study, the foliar application by amino acids 3 cm/l, putrescine 1.03 g/l, glycine betaine 1.35 g/l, betaine 0.45 g/l and proline 1.28 g/l. added to reduce stress These compounds were sprayed twice, the first spraying one month after fruit set, the second spraying two months after fruit set on "Le-Conte" pear trees that grow under conditions of water scarcity stress (60% of water requirements) and control (60% of water requirements) with any these compounds treatments. Water scarcity stress caused a reduction in vegetative parameters, macro nutrients, soluble proteins, lowest productivity per tree and fruit weight, fruit valium, fruit length and fruit width, TSS, and fruit attribute. However, the contents of proline, full phenol, and antioxidant enzyme activity were augmented in pear trees grown under water scarcity stress. application of amino acids, putrescine, and glycine betaine on stressed trees showed different responses and improvements in the yield, fruit attribute, morphological traits, macronutrients, reduction of oxidative stress and antioxidant enzyme activity. a Foliar spray amino acids 3 cm/L on "Le-Conte" pear trees grow under conditions of water scarcity stress (60% CWR) during after fruit set stage to harvest gave the greatest yield per tree, fruit weight, fruit valium, fruit length, fruit diameter, TSS and vegetative growing compared to control (60% CWR) in two seasons. It could be recommended that foliar spray of amino acids, putrescine and glycine betaine, especially amino acids, could be commercially intended for the stimulation of pear trees cultivated under water scarcity stress. [ABSTRACT FROM AUTHOR]

The low salinity tolerance of almond cultivars can cause a significant setback in almond production. Therefore, selecting suitable cultivars and rootstocks in salinityaffected areas can facilitate sustainable crop production. In this research, the effects of two wild almond species, Badamkohiand Arjan as rootstocks on the salinity tolerance of 'Sahand' as a scion were investigated through in vitro culture. A factorial experiment of 2 (species) × 4 (levels of salinity) was conducted in a completely randomized design (CRD) with 4 replications. The results showed that 'Sahand' grafted on Badamkohi had the higher fresh and dry weight than grafted on Arjan in all level of salinity. The Na+ and Clions contents inthe shoots and root of both micrografting combinations increased with increasing salinity. However, their amount in the shoot and the root of 'Sahand'/Arjan plants were significantly higher than those ions in 'Sahand'/Badamkohi plants at 80 and 120 mM NaCl. The amount of total chlorophyll in 'Sahand' grafted on Badamkohi was 0.68 mg g1 FW which was significantly higher than the total chlorophyll of the same scion grafted on Arjan rootstock (0.51 mg g1 FW) at 120 mM NaCl. The highest leaf cell electrical leakage occurred in 'Sahand' grafted on Arjan which was significantly higher than leaf electrical leakage of the same scion grafted on Badamkohi at 120 mM NaCl. The grafting combination of 'Sahand'/Badamkohi showed a higher proline and glycine betaine content, compared to the grafting combination of 'Sahand'/Arjan. The shoot and root antioxidant enzyme activities (SOD, POX and CAT) in micrografting combination of 'Sahand'/Badamkohi were also significantly higher than those in 'Sahand'/Arjan. It can be concluded that 'Sahand/Badamkohi combination is a suitable choice for the regions with late spring frost and saline conditions. [ABSTRACT FROM AUTHOR]

Paracoccus sp. strain DMF (P. DMF from henceforth) is a gram-negative heterotroph known to tolerate and utilize high concentrations of N,N-dimethylformamide (DMF). The work presented here elaborates on the metabolic pathways involved in the degradation of C1 compounds, many of which are well-known pollutants and toxic to the environment. Investigations on microbial growth and detection of metabolic intermediates corroborate the outcome of the functional genome analysis. Several classes of C1 compounds, such as methanol, methylated amines, aliphatic amides, and naturally occurring quaternary amines like glycine betaine, were tested as growth substrates. The detailed growth and kinetic parameter analyses reveal that P. DMF can efficiently aerobically degrade trimethylamine (TMA) and grow on quaternary amines such as glycine betaine. The results show that the mechanism for halotolerant adaptation in the presence of glycine betaine is dissimilar from those observed for conventional trehalose-mediated halotolerance in heterotrophic bacteria. In addition, a close genomic survey revealed the presence of a Co(I)-based substrate-specific corrinoid methyltransferase operon, referred to as mtgBC. This demethylation system has been associated with glycine betaine catabolism in anaerobic methanogens and is unknown in denitrifying aerobic heterotrophs. This report on an anoxic-specific demethylation system in an aerobic heterotroph is unique. Our finding exposes the metabolic potential for the degradation of a variety of C1 compounds by P. DMF, making it a novel organism of choice for remediating a wide range of possible environmental contaminants. [ABSTRACT FROM AUTHOR]

Introduction: In light of upcoming climate change, there is an urgent requirement for tree improvement regarding adaptability to drought-caused stress and the development of quick and reliable screening methodologies for genotypes' drought tolerance. White poplar is, despite its high adaptability, considered to be an endangered tree species in Serbia, which gives it special importance in the preservation and improvement of biodiversity of riparian ecosystems. The main goal of this research was to evaluate the tolerance of five white poplar clones to the presence of polyethylene glycol (PEG 6000 molecular weight 6000) (different concentrations (e.g. 0 g/L, 1 g/L, 10 g/L, 20 g/L, and 50 g/L) in Aspen Culture Medium (ACM). Methods: The tolerance of the clones was evaluated by using morphological parameters (shoot fresh and dry weight, root fresh and dry weight), photosynthetic pigments (contents of chlorophyll a, chlorophyll b, carotenoids, and chlorophyll a+b), and biochemical parameters (total phenolic content, total flavonoid content, ferric reducing antioxidant power, antioxidant activities (DPPH activity and ABTS assay), free proline content and glycine betaine content. Results and Discussion: The values of morphological and photosynthetic pigments declined with an increase in the concentration of PEG 6000. At a concentration of 50 g/L, the content of shoot fresh mass decreased by 41%, the content of Chl a by 68%, Chl b by 65%, and Car by 76% compared to the control. Also, at the same medium, there was an increase in the content of total phenols, accumulation of proline, the content of glycine betaine as well as in antioxidant activity. Based on the obtained results, it can be assumed that more droughttolerant clones are characterized by high values for biomass, high content of photosynthetic pigments, and high content of proline and glycine betaine in conditions similar to drought in vitro. Clone L-80 showed better results in most of the tested parameters, especially compared to the reference clone Villafranca. [ABSTRACT FROM AUTHOR]

Maize production and productivity are affected by drought stress in tropical and subtropical ecologies, as the majority of the area under maize cultivation in these ecologies is rain-fed. The present investigation was conducted to study the physiological and biochemical effects of 24-Epibrassinolide (EBR) as a plant hormone on drought tolerance in maize. Two maize hybrids, Vivek hybrid 9 and Bio 9637, were grown under three different conditions: (i) irrigated, (ii) drought, and (iii) drought+EBR. A total of 2 weeks before the anthesis, irrigation was discontinued to produce a drought-like condition. In the drought+EBR treatment group, irrigation was also stopped, and in addition, EBR was applied as a foliar spray on the same day in the drought plots. It was observed that drought had a major influence on the photosynthesis rate, membrane stability index, leaf area index, relative water content, and leaf water potential; this effect was more pronounced in Bio 9637. Conversely, the activities of antioxidant enzymes such as catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD) increased in both hybrids under drought conditions. Specifically, Vivek hybrid 9 showed 74% higher CAT activity under drought conditions as compared to the control. Additionally, EBR application further enhanced the activity of this enzyme by 23% compared to plants under drought conditions. Both hybrids experienced a significant reduction in plant girth due to drought stress. However, it was found that exogenously applying EBR reduced the detrimental effects of drought stress on the plant, and this effect was more pronounced in Bio 9637. In fact, Bio 9637 treated with EBR showed an 86% increase in proline content and a 70% increase in glycine betaine content compared to untreated plants under drought conditions. Taken together, our results suggested EBR enhanced tolerance to drought in maize hybrids. Hence, pre-anthesis foliar application of EBR might partly overcome the adverse effects of flowering stage drought in maize.

Background: Choline oxidase, a flavoprotein, is an enzyme that catalyzes the reaction which converts choline into glycine betaine. Choline oxidase started its journey way back in 1933. However, the impact of the high temperature on its structure has not been explored despite the long history and availability of its crystal structure. Both choline oxidase and its product, glycine betaine, have enormous applications spanning across multiple industries. Understanding how the 3D structure of the enzyme will change with the temperature change can open new ways to make it more stable and useful for industry. Process: This research paper presents the in-silico study and analysis of the structural changes of A. globiformis choline oxidase at temperatures from 25 °C to 60 °C. A step-wise process is depicted in Fig. 1. Results: Multiple sequence alignment (MSA) of 11 choline oxidase sequences from different bacteria vs Arthrobacter globiformis choline oxidase showed that active site residues are highly conserved.The available crystal structure of A. globiformis choline oxidase with cofactor Flavin Adenine Dinucleotide (FAD) in the dimeric state (PDB ID: 4MJW)1 was considered for molecular dynamics simulations. A simulated annealing option was used to gradually increase the temperature of the system from 25 °C to 60 °C. Analysis of the conserved residues, as well as residues involved in Flavin Adenine Dinucleotide (FAD) binding, substrate binding, substate gating, and dimer formationwas done. At high temperatures, the formation of the inter-chain salt bridge between Arg50 and Glu63 was a significant observation near the active site of choline oxidase. Conclusion: Molecular dynamics studies suggest that an increase in temperature has a significant impact on the extended Flavin Adenine Dinucleotide (FAD) binding region. These changes interfere with the entry of substrate to the active site of the enzyme and make the enzyme inactive.

Introduction Potato (Solanum tuberosum L.) is an important food and cash crop having the first rank in the world from non grain crops to ensure food security. The tubers produced through the conventional propagation are characterized by low multiplication rate and susceptibility to pathogens. Microtubers are an ideal propagating material for producing high quality seed potatoes. Nowadays, the production, application, and biological risk assessment of nano-scaled products have attracted global concerns in various fields such as agricultural, biotechnological, medicinal, and plant sciences. Chitosan, a biocompatible polymer, has been widely utilized to improve the production of nano-chemicals, thereby improving crop growth, productivity, and immunity. Nanotechnology plays an important role in modern agriculture to address global challenges such as climate change, severity of plant diseases and the limited availability of important plant nutrients. Polymer-based nano-formulations have recently received the greatest attention with the key objectives of developing less harmful, plant growth promoting and protective agents of biodegradable and natural origin. Use of chitosan-based nanoparticles in agriculture field is still in a budding phase. Significant outcomes have been reported in in vitro and a few in vivo studies in plant growth and protection by chitosan-based nanomaterials. Materials and Methods MS medium containing 80 g of sucrose, containing glycine betaine at concentrations of 20 and 40 mg/l, chitosan at a concentration of 240 mg/l, glycine betaine 20 and chitosan 240 mg/l, glycine betaine 40 and chitosan 240 mg/l, 120 mg/l, glycine betaine nanocomposite coated with chitosan 120 and 240 mg/l and control treatment, as well as nonsalinity treatments with the same compounds and concentrations mentioned for salinity were cultured. The study was performed in randomized complete block design with three replications and sixteen treatment. Glycine betaine nanocomposite coated with chitosan were prepared at Maragheh University as follows. Chitosan, glycine betaine, and triphosphate are major consumables. First, chitosan was dissolved well with acetic acid under the influence of temperature. Then, a certain amount of glycine betaine was dissolved in distilled water and added to the chitosan. Tri-polyphosphate (TPP) was dissolved in distilled water at a certain volume ratio and added dropwise to the mixture of chitosan and glycine betaine. The precipitate obtained under the freeze-drying process lead to the preparation of its powder. Results and Discussion According to the comparison of the means, treatment of glycine betaine coated with chitosan nanocomposite at a concentration of 120 mg/l produced the highest number of microtuber during the experiment from the first month to the final month. The nanocomposite was more capable of improving growth and biomass than the bare ZnONPs in pepper. The application of the nanocomposite increased the concentration of chlorophylls (51%), carotenoids (70%), proline (2-fold), and proteins (about 2- fold). The supplementation of culture medium with the nanomaterials upregulated enzymatic antioxidant biomarkers (catalase and peroxidase) (Asgari-targhi et al., 2021). The highest mean microtuber weight was related to the nanocomposite treatment of 120 mg/l with a weight of 29 mg. In the microtuber diameter, this treatment had the highest value. The results of analysis of variance in Table 1 indicate that the effect of moderate salinity and the interaction of moderate salinity and nanocomposite treatments are not significant and the effect of experimental treatments is significant at the level of 5% probability. Due to the fact that the most important trait in the potato microtuberization is microtuber yield, so in the experiment, the highest microtuber yield was earned nanocomposite treatment with 131 mg and the lowest in control treatment with 87 mg. It seems that by using stress-reducing compounds such as glycine betaine and chitosan and nanocomposites, these compounds increase the amount of genes responsible for the formation of microtuber, and as a result, increasing the proteins involved in stresses induce more microtuberization. Also, nanocomposite materials, more assimilated materials may be transferred from the roots to microtuberization processes. Conclusion The microtuber produced in the glycine betaine coated with chitosan nanocomposite treatment produced the highest number of microtubers in the first, second, third, and final months. In treatments with moderate salinity in the first, second, third and final months, the number of microtuber and eyes and sprouted microtubers had the highest amount compared to the treatment without moderate salinity. Also, plants treated with glycine betaine voated with chitosan nanocomposite in the microtuber trate showed a greater effect than chitosan and glycine betaine with chitosan. According to the findings of this study, it seems that the use of nanocomposite materials in increasing the microtuber and reducing the vegetative growth of potato shoots has been made in Agria cultivar.

Abstract We investigated the chemopreventive effects of beer, nonalcoholic beers (NABs), and beer-components (glycine betaine (GB)) on NNK-induced lung tumorigenesis in A/J mice, and the possible mechanisms underlying the antitumorigenic effects of beer, NABs, and beer-components. Beer, NABs, and GB reduced NNK-induced lung tumorigenesis. We investigated the antimutagenicity of beer, NABs and beer-components (GB and pseudouridine (PU)) toward the mutagenicity of 1-methyl-3-nitro-1-nitrosoguanidine (MNNG) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). Beer, NABs, and beer components were antimutagenic toward MNNG and NNK in the Ames test using S. typhimurium TA1535. In contrast, MNNG and NNK mutagenicity detected in S. typhimurium YG7108, a strain lacking O 6-methylguanine DNA methyltransferases (ogt ST and ada ST) did not decrease in the presence of beer, NABs, or beer components, suggesting that they may mediate its antimutagenic effect by enhancing DNA damage repair. Phosphorylation of Akt and STAT3, with or without epidermal growth factor stimulation, in lung epithelial-like A549 cells were significantly decreased following beer, NABs, GB and PU. They targeted both the initiation and growth/progression steps of carcinogenesis, specifically via antimutagenesis, stimulation of alkyl DNA-adduct repair, and suppression of Akt- and STAT3- mediated growth signaling. GB and PU may contribute, in part, to the biological effects of beer and NABs via the suppression of Akt and STAT3 phosphorylation.