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This study aims to monitor the implications of climate change on savanna ecosystem drought using time series data from the Landsat 8 sensor, spanning from 2013 to 2022. We employed a remote sensing computational approach with the semi-automatic classification plugin (SCP) in the open-source QGIS software. Specifically, we utilized channels from the operational land imager (OLI), including Band 4 Red (0.636-0.673 µm) and Band 5 Near-Infrared (0.851-0.879 µm), as well as Thermal Infrared Sensor (TIRS) channels Band 10 TIRS-1 (10.60-11.19 µm) and Band 11 TIRS-2 (11.50-12.51 µm). These channels were used to calculate the vegetation health index (VHI) using the raster calculator, followed by data reclassification with specific thresholds to compare drought-affected areas. Our findings reveal a significant impact of climate change on savanna ecosystem drought over the decade, with the most extreme conditions observed in 2015 and 2019, where drought coverage reached 42.74% and 26.58%, respectively. Other years exhibited relatively low drought dynamics, affecting less than 3% of the area. This period aligns with the el niño-southern oscillation (ENSO) phenomenon, particularly the transition from El Niño to La Niña, known to cause global weather variations, and significantly influenced by the positive phase of the Indian Ocean dipole (IOD). The novelty of this research lies in two main aspects: firstly, the use of Landsat satellite sensors for this specific region has not been extensively studied before; secondly, the discovered impacts of drought in relation to global climate change phenomena are particularly noteworthy. A limitation of this study is the relatively short investigation period of just one decade, which does not fully capture the long-term impacts of climate change. Future research is recommended to utilize imagery with higher temporal resolution over extended periods to better represent extreme climate events and derive drought patterns over durations exceeding one decade. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agriculture & Nature / Kahramanmaraş Sütçü İmam Üniversitesi Tarım & Doğa Dergisi is the property of Kahramanmaras Sutcu Imam Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to examine the effects of seed priming with different boron concentrations on the germination and seedling growth of spinach under drought-stress conditions. Seeds of the spinach cultivar Matador and sodium borate (Na2B8O13.4H2O) were used as materials. The seeds were primed with 0 (distilled water), 1, 10, 100, 500, and 1000 ppm B for 24 hours, with unprimed seeds serving as a control. Drought stress was induced by polyethylene glycol (PEG 6000) solution at a water potential of -3 bar and distilled water denoted as control conditions. A standard germination test was performed between papers at 20°C for 14 days. The germination percentage, mean germination time, germination index, seedling growth parameters, and root/shoot length ratio were investigated. The findings revealed that drought stress reduced germination percentage, germination index, and seedling growth of unprimed seeds of spinach. However, boron priming improved these parameters while mitigating the negative effects of drought stress. Under drought conditions, seed priming with 1 ppm B shortened mean germination time. Similarly, seedling fresh and dry weight of spinach were improved by seed priming with 100-1000 ppm B, whereas root growth was stimulated by 10 ppm B. The highest root/shoot ratio was found at 10 ppm B. Boron priming was more efficient in promoting seedling growth than germination in spinach. As a result, seed priming with 10-100 ppm B should be recommended to improve the germination and seedling growth performance of spinach in the event of drought stress after planting. [ABSTRACT FROM AUTHOR]

To study the changes in structural characteristics of oak forests due to tree mortality, the Shalam forested area in the western Iran was selected. For this, 20 stands with different topographical conditions were selected to determine whether the stand or tree characteristics changed following tree mortality as well as were essential factors in the variation of tree mortality. In each stand, three plots of 1000 m² were established randomly and systematically, and variables of tree diameter (diameter at breast height), maximum and minimum crown diameter, origin and form of trees and shrubs of all species, crown dieback percent, and number of dead trees were measured and recorded. Results showed that the tree mortality rate in the study area averaged 35.33 trees/ha, and 97.65% of it was related to Persian oak. The amount of stand density, basal area, and canopy cover decreased by 15.7%, 14.23%, and 4.19%, respectively, due to tree mortality. The abundance of most species has decreased, and the rate of species frequency reduction was more remarkable in Persian oak and Acer monspessulanum. Of the trees, 20.37% were healthy, and 79.63% were affected by crown dieback. The highest density of tree mortality was in the diameter classes of 10–30 cm, and the highest rate of tree mortality was in the diameter classes of 5, 60, and 75 cm. Based on the dead tree density, the pattern of tree mortality was L-shaped, while based on the dead tree percentage, the pattern was U-shaped. Tree mortality correlated significantly with diameter at breast height. Multiple regression analysis also showed that tree mortality has a significant relationship with stand basal area, diameter at breast height, and stand canopy cover; so these variables played a significant role in variation of forest structure under effect of tree decline. [ABSTRACT FROM AUTHOR]

This research investigates the exposure of plant species to extreme drought events in the Brazilian Atlantic Forest, employing an extensive dataset collected from 205 automatic weather stations across the region. Meteorological indicators derived from hourly data, encompassing precipitation and maximum and minimum air temperature, were utilized to quantify past, current, and future drought conditions. The dataset, comprising 10,299,236 data points, spans a substantial temporal window and exhibits a modest percentage of missing data. Missing data were excluded from analysis, aligning with the decision to refrain from using imputation methods due to potential bias. Drought quantification involved the computation of the aridity index, the analysis of consecutive hours without precipitation, and the classification of wet and dry days per month. Mann–Kendall trend analysis was applied to assess trends in evapotranspiration and maximum air temperature, considering their significance. The hazard assessment, incorporating environmental factors influencing tree growth dynamics, facilitated the ranking of meteorological indicators to identify regions most exposed to drought events. The results revealed consistent occurrences of extreme rainfall events, indicated by positive outliers in monthly precipitation values. However, significant trends were observed, including an increase in daily maximum temperature and consecutive hours without precipitation, coupled with a decrease in daily precipitation across the Brazilian Atlantic Forest. No significant correlation between vulnerability ranks and weather station latitudes and elevation were found, suggesting that geographical location and elevation do not strongly influence observed dryness trends. [ABSTRACT FROM AUTHOR]

This study focused on mitigating effects of an animal-derived biostimulant on sugar beet plantlets subjected to drought stress. The experiment was performed at the Seed Science and Technology Laboratory of the Eskişehir Osmangazi University, Faculty of Agriculture, Department of Field Crops, in 2024. It was established by the randomized plot 2x5 factorial experimental design (ANOVA) with four replications. The sugar beet cultivar Mohican was sprayed by an animalderived biostimulant (Andolamin®) containing 11% amino acids. Different levels of the biostimulant (control, 12.5, 25, 50, and 75 mL/L) were treated twice at 2-day intervals. Morphological and physiological measurements were made at 7 days after the first application on sugar beet plants grown under two irrigation regimes (water deficit (WD) 50% of field capacity and well-watered (WW) 80% of field capacity). The findings showed that drought had a hazardous impact on sugar beet's number of leaves (NL), fresh (LFW) and leaf dry weight (LDW), relative water content (RWC), and leaf area (LA). Leaf surface temperature (LST), chlorophyll content (Chl), and electrolyte leakage (EL) were higher in plants under water deficit. Foliar biostimulant application mitigated the effect of drought stress on seedlings through improving LFW, LDW, Chl, EL, and LA. On the other hand, biostimulant treatment had no significant effects on NL, and RWC in seedlings exposed to drought stress. It was concluded that animal-derived biostimulant application may be used for alleviating the harmful effects of drought stress and may stimulate the growth of sugar beet seedlings. [ABSTRACT FROM AUTHOR]

The study was conducted to determine the sensitivity of forage pea to drought stress intensities and the contribution of smoke solutions in preventing this sensitivity. For the smoke solution, dried poppy harvest residues were prepared with a special mechanism. Within this scope, two different concentrations (1 and 10%) of poppy smoke solution were utilized in priming of two distinct forage pea varieties (Gap pembesi and Özkaynak). After priming, the seeds were sowing in pots and it was exposed to moderate and severe drought conditions after 21 days. Effects of smoke solutions and drought stress in varieties were assessed by physically (shoot length) and chemical parameters (crude protein, ADF. NDF, Ca, Mg, P and K). Both forage pea varieties have been observed that crude protein and mineral substance (except Ca) contents decrease significantly under drought stress, especially in severe drought. This loss was increased again by eliminating both doses (especially 10%) of smoke solutions. In fact, under normal growing conditions (control), 10% smoke solution application had the highest crude protein in both varieties. However, the effect of drought and the defense mechanism of smoke solution created differences in forage pea varieties based on parameters. In general, the Özkaynak was more resistant to drought and the response to smoke solution was stronger. In conclusion, by incorporating the poppy-smoke solution into the drought stress mitigation strategy, this approach not only curbed environmental losses but also mitigated the impacts of drought stress. [ABSTRACT FROM AUTHOR]

Drought stress remains a major environmental factor which decreases the yield and productivity of most cereals growing worldwide. The research was carried out to assess correlation and path coefficient among 20 bread wheat (Triticum aestivum L.) genotypes. The treatments under drought conditions affected all agronomic traits, and the genotypes showed a significant difference. However, the results from the ambient tunnel were satisfactory, and some interesting observations were made. The present experiment was undertaken to estimate the correlation coefficient between grain yield and different yield contributing characters. The experiment was laid-out with two replications using an alpha lattice design. The study aimed to determine the degree of association between yield and yield attributing characters of drought-tolerant wheat populations using correlation and path analyses. The experiment's results demonstrated a highly significant difference in all the attributes examined between the wheat varieties, and water restriction dramatically reduced those traits. Partitioning of correlation coefficients into direct and indirect effects revealed. strong positive direct effects of spike weight on grain yield under drought-stressed conditions. Spike weight expressed the highest positive correlation (0.696) with grain yield, whereas spikelet per spike showed the lowest positive correlation (0.2) with tiller/m² [ABSTRACT FROM AUTHOR]

This study was to investigate the effects of three exogenous substances on chemical constituents of Isatis indigotica leaves and their efficacy in alleviating drought stress, and explore the methods of applying exogenous substances to efficient cultivation of Isatis indigotica. Polyethylene glycol (PEG) was used to simulate drought stress to deal with seeds of Isatis indigotica at the germination stage (concentration: 0, 10%, 15%, and 20%). Simultaneous operation of exogenous growth regulators [microbial inoculum (MI), γ-aminobutyric acid (GABA) and salicylic acid (SA)] and PEG were implemented in seeds of Isatis indigotica. The effects of drought stress and the mitigation of exogenous substances were observed by statistics of seed germination potential, germination rate, hypocotyl length, and radicle length of each treatment. The effects of exogenous substances on the content of alkaloids, crude protein and free amino acids in the leaves of Isatis indigotica grown in a greenhouse were determined after spraying exogenous substances on the plants. The differences of germination potential, germination rate, hypocotyl length, and radicle length among 15% PEG stress treatment, 10% PEG stress treatment and the control were significant (P<0.05). According to the predesigned germination standard, the seeds did not germinate under 20% PEG stress treatment. When the PEG concentration was 15%, the results of seed germination potential and germination rate after adding MI were significantly different from those under stress alone (P<0.05). When exposed to 10% PEG stress, the supplementation of GABA led to a notable increase in radicle length of Isatis indigotica seeds, showing significant differences compared to other three treatments. The application of MI and GABA under 15% PEG stress resulted in a significant increase in the radicle and hypocotyl length of Isatis indigotica seeds compared to other two treatments. The content of the total alkaloids in leaves of Isatis indigotica was significantly increased after spraying GABA. Meanwhile, the contents of crude protein and the total free amino acids were kept constant after spraying exogenous substances. Application of MI and GABA could alleviate drought stress of Isatis indigotica. The content of the total alkaloids in leaves of Isatis indigotica could significantly increase after spraying GABA. [ABSTRACT FROM AUTHOR]

Introduction: Crops are vulnerable to precipitation and heat extremes during late spring through summer. Methods: We analyzed for a north-central U.S. region short-term drought and agricultural heat stress during April-May-June-July. We used the 4-km Parameter Elevation Regression on Independent Slopes Model (PRISM) for observations, aggregated to a 25-km grid, and two 25-km Regional Climate Model version 4 (RegCM4) simulns used either GFDL- or MPI-GCM boundary conditions. We chose 1981-2000 as our contemporary time period, and 2041-2060 as our scenario time period, which used the Representative Concentration Pathway 8.5 emissions scenario. We used object-oriented analysis to identify events of interest in observations and simulations by identifying objects in a space-time domain that meet specified criteria, such as exceeding a heat-stress temperature threshold. The event diagnosis allowed analysis of compound events, occurring when temperature and drought objects overlap. Results: Identified objects yielded events that can undermine agricultural productivity and which are thus relevant to decision makers, making them building blocks for possible climate storylines. The observations and simulations showed similar spatial distributions of event frequencies across the analysis region. However, the simulations attained this distribution by having fewer events that tend to cover larger areas compared to observed events, suggesting that the effective resolution of the simulations was coarser than their 25-km grids. Short-term drought frequency increased and heat-stress frequency decreased in transitioning to the scenario climate. When compounding occurred heat-stress events generally preceded the short-term drought events. The overlapping, compound events tended to be more extreme compared to non-overlapping events of either type. Discussion: The information yielded projected changes in these agriculturally motivated events. One prominent conditional behavior emerging from the work was that a heat-stress event should be a warning to watch for potential drought, as both could compound each other to more intense levels. [ABSTRACT FROM AUTHOR]

Drought (water shortage) can substantially limit the yield and economic value of rose plants (Rosa spp.). Here, we characterized the effect of exogenous calcium (Ca2+) on the antioxidant system and photosynthesis-related properties of rose under polyethylene glycol 6000 (PEG6000)- induced drought stress. Chlorophyll levels, as well as leaf and root biomass, were significantly reduced by drought; drought also had a major effect on the enzymatic antioxidant system and increased concentrations of reactive oxygen species. Application of exogenous Ca2+ increased the net photosynthetic rate and stomatal conductance of leaves, enhanced water-use efficiency, and increased the length and width of stomata following exposure to drought. Organ-specific physiological responses were observed under different concentrations of Ca2+. Application of 5 mmol. L-1 Ca2+ promoted photosynthesis and antioxidant activity in the leaves, and application of 10 mmol. L-1 Ca2+ promoted antioxidant activity in the roots. Application of exogenous Ca2+ greatly enhanced the phenotype and photosynthetic capacity of potted rose plants following exposure to drought stress. Overall, our findings indicate that the application of exogenous Ca2+ enhances the drought resistance of roses by promoting physiological adaptation and that it could be used to aid the cultivation of rose plants. [ABSTRACT FROM AUTHOR]

Abiotic stress reduces plant yield and quality. WRKY transcription factors play key roles in abiotic stress responses in plants, but the molecular mechanisms by which WRKY transcription factors mediate responses to drought and osmotic stresses in apple (Malus × domestica Borkh.) remain unclear. Here, we functionally characterized the apple Group III WRKY gene MdWRKY115. qRT-PCR analysis showed that MdWRKY115 expression was up-regulated by drought and osmotic stresses. GUS activity analysis revealed that the promoter activity of MdWRKY115 was enhanced under osmotic stress. Subcellular localization and transactivation assays indicated that MdWRKY115 was localized to the nucleus and had a transcriptional activity domain at the N-terminal region. Transgenic analysis revealed that the overexpression of MdWRKY115 in Arabidopsis plants and in apple callus markedly enhanced their tolerance to drought and osmotic stresses. DNA affinity purification sequencing showed that MdWRKY115 binds to the promoter of the stress-related gene MdRD22. This binding was further verified by an electrophoretic mobility shift assay. Collectively, these findings suggest that MdWRKY115 is an important regulator of osmotic and drought stress tolerance in apple. [ABSTRACT FROM AUTHOR]

Drought poses a significant challenge to rice cultivation in Asia's rain-fed regions, which is expected to worsen with climate change. This article presents a comprehensive review of the current state of knowledge on drought tolerance in rice, based on a literature review of 52 relevant articles. The articles were chosen based on their relevance to the topic of drought tolerance in rice. The selected articles were then analyzed using a qualitative approach to summarize and synthesize their findings into three main sections: impact, performance, and recent trends. The article highlights several key findings on the development of drought-tolerant rice cultivars, including the identification of genes that control responses to water availability, the use of submergence-tolerant varieties in flood-prone lowlands, and the importance of physiological, biochemical, and molecular adaptation processes in improving rice's tolerance to drought stress. The article emphasizes the importance of marker-assisted breeding and cultivation in semi-arid and rainfed environments to develop more drought-tolerant cultivars. The development of drought-tolerant rice cultivars is crucial to ensure food security and mitigate the effects of climate change in Asia's rain-fed regions. The article also discusses various types of droughts and their effects on different plant species and drought pressures. As the global population increases, the demand for rice as a dependable food crop also rises. To meet this demand, rice cultivation must be expanded to rainfed areas. However, rice's adaptation mechanisms and habitat make it one of the most challenging crops for breeders to develop drought-tolerant varieties. Overall, this article provides important insights and recommendations to improve rice productivity and address the challenges associated with drought in rice cultivation. [ABSTRACT FROM AUTHOR]

This study covered 2 locations, using 3 replications with randomized complete block design (RCBD) as a split-plot factorial arrangement, to determine the effect of both irrigation (I1, I2, & I3) and salicylic acid application (S1), and non-SA (S0) treatments, respectively, on sunflower seed oil % and main phytochemical components %, at ache-forming, flowering, and vegetative stages, compared to complete irrigation (I4). SA applied with full irrigation resulted in the highest values of seed oil % and overwhelming majority phytochemical components. On the contrary, the lowest values were noted by none (SA) application with skipping irrigation at the flowering-stage (I2S0). [ABSTRACT FROM AUTHOR]

This research focused on the evaluation of twelve newly bred rice genotypes with diverse morphological traits under aerobic cultivation to develop strategies for water conservation while maintaining grain productivity and quality. The experiment was conducted during the summer season of 2016, employing a Randomized Complete Block Design (RCBD) with wetland cultivation as a control. For analysis, various vegetative and reproductive traits namely, Plant height, Number of Tillers, Shoot Weight, Days to 50% flowering, Days to Maturity, Number of Productive Tillers, Panicle Length, Grain Weight, Length of the seed, Breadth of the seed, Ratio of Length and Breadth of the Seed, and Test weight of 100 seeds were recorded. Data on analysis of variance revealed the significant difference for days to flowering, maturity, plant height, panicle length, test weight, and grain yield under aerobic and wetland cultivation methods during the summer season, 2016, suggesting these traits are under high genetic control. Genetic parameters such as percentage of GCV, PCV, Heritability, and GAM were estimated across 13 parameters comprising vegetative and reproductive characters. The findings suggest a considerable amount of genetic variability for most traits, providing a foundation for the potential implementation of an effective selection procedure in breeding new rice varieties within the selected genotypes. [ABSTRACT FROM AUTHOR]

Citrus is the typical mycorrhizal fruit tree species establishing symbiosis with arbuscular mycorrhizal (AM) fungi. However, arbuscule development and senescence in colonized citrus roots, especially in response to drought stress, remain unclear, which is mainly due to the difficulty in clearing and staining lignified roots with the conventional method. Here, we improved the observation of colonized roots of citrus plants with the sectioning method, which enabled the clear observation of AM fungal structures. Furthermore, we investigated the effects of one week of drought stress on arbuscule development and senescence with the sectioning method. Microscopy observations indicated that drought stress significantly decreased mycorrhizal colonization (F% and M%) although it did not affect plant growth performance. Fluorescence probes (WGA 488 and/or Nile red) revealed that drought stress inhibited arbuscule development by increasing the percentage of arbuscules at the early stage and decreasing the percentages of arbuscules at the midterm and mature stages. Meanwhile, drought stress accelerated arbuscule senescence, which was characterized by the increased accumulation of neutral lipids. Overall, the sectioning method developed in this study enables the in-depth investigation of arbuscule status, and drought stress can inhibit arbuscule development but accelerate arbuscule senescence in the colonized roots of citrus plants. This study paves the way to elaborately dissecting the arbuscule dynamics in the roots of fruit tree species in response to diverse abiotic stresses. [ABSTRACT FROM AUTHOR]

Agricultural droughts can cause many serious hazards. Drought monitoring indices, namely Normalized Difference Vegetation Index (NDVI), Atmospherically Resistant Vegetation Index (ARVI), Soil Adjusted Vegetation Index (SAVI), and Enhanced Vegetation Index (EVI) have been used for an agricultural drought assessment. Satellite images from the Kolar region of Karnataka are used to calculate these indices. This paper proposes an integration model based on Convolutional Neural Networks (CNN) and a bio-inspired algorithm (Sparrow Search Algorithm (SSA) and Barnacles Mating Optimizer (BMO)) considering the indices as population. Performance is compared with the standalone CNN model in terms of efficiency. For the CNN, the accuracy, time taken for Epoch1, and time taken for Epoch2 is 91%, 16s (3s/step), and 2s (2s/step), respectively. For the CNN integrated with SSA, it is 94%, 3s (3s/step) and 0s (43ms/step), respectively. For the CNN integrated with BMO, it is 94%, 3s (2s/step) and 0s (46ms/step) respectively. [ABSTRACT FROM AUTHOR]

Plant Myeloblastosis (MYB) proteins function crucially roles upon variegated abiotic stresses. Nonetheless, their effects and mechanisms in rose (Rosa chinensis) are not fully clarified. In this study, we characterized the effects of rose RcMYB8 under salt and drought tolerances. For induction of the RcMYB8 expression, NaCl and drought stress treatment were adopted. Rose plants overexpressing RcMYB8 displayed enhanced tolerance to salinity and drought stress, while silencing RcMYB8 resulted in decreased tolerance, as evidenced by lowered intra-leaf electrolyte leakage and callose deposition, as well as photosynthetic sustainment under stressed conditions. Here, we further show that RcMYB8 binds similarly to the promoters of RcPR5/1 and RcP5C51 in vivo and in vitro. Inhibiting RcP5CS1 by virus-induced gene silencing led to decreased drought tolerance through the reactive oxygen species (ROS) homeostatic regulation. RcP5CS1-silenced plants showed an increase in ion leakage and reduce of proline content, together with the content of malondialdehyde (MDA) increased, lowered activities of Catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD). Our study highlights the transcriptional modulator role of RcMYB8 in drought and salinity tolerances, which bridges RcPR5/1 and RcP5CS1 by promoting ROS scavenging. Besides, it is probably applicable to the rose plant engineering for enhancing their abiotic stress tolerances. [ABSTRACT FROM AUTHOR]

The main purpose of the study was to clarify the effect of selenium (Se) on DNA damage and DNA methylation in wheat (Triticum aestivum L.) plants exposed to polyethylene glycol (PEG)-induced drought stress under in vitro tissue culture. Random amplified polymorphic DNA (RAPD) and coupled restriction enzyme digestion-random amplification (CRED-RA) were utilized to explain the DNA damage grade and variations in DNA methylation patterns, respectively. The outcomes indicate that drought stress gives rise to a rise in RAPD profile variations (as DNA damage) and a decrease in genomic template stability (GTS) rate and DNA methylation changes. According to the RAPD data, the greatest GTS value was computed at 56.9% (5% PEG 6000), and the lowest GTS value was 41.2% (15% PEG 6000), demonstrating the adverse effects of PEG 6000. However, DNA damage can be reduced by treatment with sodium selenate (2, 4, and 6 µM of Na2SeO4) together with PEG (5%, 10%, and 15% PEG 6000)-induced water deficits. Moreover, according to CRED-RA analysis, PEGinduced DNA methylation rates were changed after treating different doses of Se. These data demonstrate that Se dosedependently modulates both DNA damage and methylation alterations induced by drought in wheat. [ABSTRACT FROM AUTHOR]

Copyright of Agronomía Colombiana is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study was conducted to investigate the effect of foliar application of amino acids on yield and yield components of oil rapeseed under late-season drought stress conditions. The experiment was conducted as factorial based on a randomized complete blocks design in the research farm of the Faculty of Agriculture at Tarbiat Modares University during the 2021-22 growing season. The experimental treatments were irrigation regimes at three levels (normal irrigation, withholding irrigation from 50% flowering stage, and withholding irrigation from pod forming) and foliar spraying at five levels (no foliar, foliar spraying 0, 1, 2, and 3 g amino acids per liter of distilled water). The results showed that plant height, shoot dry weight, 1000-seed weight, harvest index, and biological and grain yield, number of seeds per pod, and the number of pods per plant were significantly affected by the interaction of irrigation regimes and foliar spraying. The highest plant height (166.5 cm), 1000-seed weight (3.58 g), number of pods per plant (131.4) and grain yield (4514 kg ha-1) were obtained by foliar spraying of two g amino acids per litre under normal irrigation conditions. According to the results, foliar spraying 2 g amino acids per liter had the most positive effect on the yield and yield components of oil rapeseed in all irrigation regimes (normal irrigation, withholding irrigation from 50% flowering stage, and withholding irrigation from pod forming). Therefore, upon approving in future research it could be recommended to use foliar spraying with 2 g amino acids per liter in oil rapeseed cultivation. [ABSTRACT FROM AUTHOR]

Rapid and efficient recovery from water deficit stress may be one of the key determinants of drought adaptation in plants. The present study was designed to investigate drought stress tolerance and recovery in promising lentil lines at the flowering stage. For this, a factorial experiment based on the completely randomized design was conducted with three replications. The factors included 6 lentil lines, drought stress (control (irrigation at 80% FC or 20% moisture depletion), medium stress (irrigation at 55% FC or 45% moisture depletion), and severe stress (irrigation at 30% FC or 70% moisture depletion)), and three sampling times (three and six days after drought, and recovery (two days after reirrigation)). Drought stress caused a decrease in chlorophyll a, chlorophyll b, total chlorophyll, carotenoid, protein, yield, and yield components. The reduction of these traits was more remarkable at six days after stress. However, during the recovery time remarkable increase was observed in these traits. The results showed that the correlation between H2O2 and MDA was significant and positive. Furthermore, drought stress increased the amount of proline, H2O2, and MDA, which resulted in an increase in the activity of antioxidant enzymes (catalase, polyphenol oxidase, and peroxidase). An increase in the intensity and duration of the drought stress also caused an increase in H2O2 and MDA content and the activity of antioxidant enzymes. In addition, in the recovery conditions, a significant reduction in the destructive effects of stress (H2O2, MDA content) and the activity of antioxidant enzymes was visible. The results of the present study indicated that the effects of drought stress on lentil lines yield and yield components (seed number, number of pods, 100-seed weight, and seed yield) were varied. Drought stress at the flowering stage decreased the number of seeds and pods per plant, and 100-seed weight, which led to yield losses. Although line 2 had the highest yield under normal and drought stress conditions, line 1 exhibited the lowest yield under stress conditions. Based on the results of this experiment, line 2 seems to be a suitable line for culture in the regions challenged with water deficit stress. [ABSTRACT FROM AUTHOR]

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Root exudates serve as crucial mediators for information exchange between plants and soil, and are an important evolutionary mechanism for plants’ adaptation to environmental changes. In this study, 15 different abiotic stress models were established using various stress factors, including drought (D), high temperature (T), nitrogen deficiency (N), phosphorus deficiency (P), and their combinations. We investigated their effects on the seedling growth of Salvia miltiorrhiza Bunge and the activities of Solid-Urease (S-UE), Solid-Nitrite Reductase (S-NiR), Solid-Nitrate Reductase (S-NR), Solid-Phosphotransferase (S-PT), and Solid-Catalase (S-CAT), as well as the contents of polysaccharides in the culture medium. The results showed that the growth of S. miltiorrhiza was inhibited under 15 stress conditions. Among them, 13 stress conditions increased the root-shoot ratio. These 15 stress conditions significantly reduced the activity of S-NR, two combinations significantly improved the activity of S-NIR, they were synergistic stresses of high temperature and nitrogen deficiency (TN), and synergistic stresses of drought and nitrogen deficiency (DN) (p < 0.05). The activity of S-UE was significantly improved under N, D, T, synergistic stresses of drought and high temperature (DT), DN, synergistic stresses of drought and phosphorus deficiency (DP), and synergistic stresses of high temperature, nitrogen, and phosphorus deficiency (TNP) stress conditions (p < 0.05). Most stress combinations reduced the activity of S-PT, but D and T significantly improved it. (p < 0.05). The N, DN, and TN stress conditions significantly reduced S-CAT activity. The P, DT, and synergistic stresses of drought, high temperature, and phosphorus deficiency (DTP) significantly decreased the total polysaccharide content of the soil (p < 0.05). The research suggested that abiotic stress hindered the growth of S. miltiorrhiza and altered the behavior of root secretion. Roots regulated the secretion of several substances in response to various abiotic stresses, including soil nitrogen cycle enzymes, phosphorus transport-related enzymes, and antioxidant enzymes. In conclusion, plants regulate the utilization of rhizosphere substances in response to abiotic stresses by modulating the exudation of soil enzymes and polysaccharides by the root system. At the same time, soil carbon sequestration was affected by the adverse environment, which restricted the input of organic matter into the soil. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Ciencias Hortícolas is the property of Revista Colombiana de Ciencias Horticolas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sunflower production in the world is expending towards marginal areas, along with rapid changes in cultural practises like no-till planting and weed management. The frequency and severity of abiotic constraints also rise as a result of climate change. Helianthus annuus is well-known for its adaptability to a wide range of agronomic conditions, by its robust root system that is capable of absobing water from deeper soils. However, water stress lowers grain yields and fatty acid content with complex phenotypic, physiological and biochemical signs. In this study which was carried out to develop parental lines tolerant or high-tolerant to drought, physiological screenings were carried out on 8 sunflower genotypes. Genotypes were planted in pots in a greenhouse and grown at three different irrigation levels (I100, I66 and I33). The genotypes were watered together until they reached the 6-8 leaf stage. Then, each genotype was managed and irrigated solely. Number of days between sowing and floweing days, number of days between sowing and number of days between sowing and number of days to transfer the embryo to the nutrient medium, plant height, head diameter, number of seeds in the head was between 52-67 days; 65-80 days; 50-200 cm; 3.0-13.0 cm; 25-500 pieces, respectively. Plant weight, plant high, root length, number of leaf, nnmber of days from transplant to glasshouse, number of days from transplant to field was between 0.22-0.45 g; 2.09-4.62 cm; 1.70-5.27 cm; 3.60-5.87 pieces; 5 or 6 days; 10-12 days, respectively. In the experiments, it was found that two and a half generations could be achieved in one year. The genotypes K26-33 and K78-100 are located closest to the center as the most ideal genotypes in terms of the examined characteristics. In the MS environment, in terms of the characteristics examined, the genotypes K105-100, K78-100, K105-66, K26-100 and K1-100 were the preferred genotypes as they are located close to the center. [ABSTRACT FROM AUTHOR]

β-ketoacyl-CoA synthase (KCS) is an important enzyme that catalyzes the biosynthesis of very-long-chain fatty acids (VLCFAs). In this study, the genome-wide analysis and functional characterization of the KCS gene family members in common bean (Phaseolus vulgaris L.) plants were conducted, and the response of the identified gene family to abiotic stresses was evaluated. In this study, 19 KCS genes were identified and characterized in the P. vulgaris genome. The molecular weights of these KCS proteins ranged from 49.14 kDa to 60.57 kDa, their amino acid lengths varied from 437 to 534, and their pI values ranged from 8.81 to 9.47, indicating a basic nature. Segmental and tandem duplications were observed in the Pvul-KCS gene family. Phylogenetic analysis revealed that Pvul-KCS proteins clustered into three main groups with Arabidopsis thaliana and Glycine max species. Comparative mapping analysis was also conducted with A. thaliana and G. max. Expression profile comparisons indicated that these genes had different expression levels in common bean varieties and played a role in the plant's response to biotic and abiotic stresses. This study provides important insights into the biological functions of KCS genes in Phaseolus vulgaris and offers valuable information for improving drought and salt stress tolerance in common beans. [ABSTRACT FROM AUTHOR]

Copyright of Lilloa is the property of Fundacion Miguel Lillo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Drought is one of the critical limitations to agricultural soils and crop plants. Scarcity of water is increasing due to climate change that lead to increasing threats to global food security. Therefore, ecofriendly and cost effective strategies are highly desirable for mitigating drought stress along with sustainable and smart agricultural production. The aim of the study was to mitigate DS using seed priming and exogenous supplementation of ß-aminobutyric acid (BABA) in linseed (Linum usitatissimum L.). Different doses (0, 50, 100 and 150 µM) of BABA were used for seed priming agent and foliar spraying under three soil moisture levels viz., 25% (SM25), 45% (SM45) and 65% (SM65). The response variables of both experiments included different agro-botanical traits and oxidative stress indicators such as melondialdehyde content, free proline accumulation, and antioxidant defense in plants. The linseed plants showed water stress at SM25 that reduced plant height, number of branches per plant, time taken to flower initiation and heading, and root and shoot dry weights. Additionally, the number of capsules and seeds per capsule showed a significant decline at SM25, which led to a drastic reduction in 100-seed weight yield in linseed plants in both experiments. However, seed priming and foliar supplementation with of BABA (50-100 µM) significantly improved these morpho-agronomical attributes in linseed plants under DS. The results revealed that the BABA was fully active in linseed plants at SM25. Interestingly, the combination of SM25 with BABA significantly improved the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and peroxidase (POD) activity, which significantly enhanced DS tolerance in linseed plants. These findings might be useful to oil seed breeders and farmers linseed for breeding program in linseed plants as well as sustainable agricultural production of oil seed crop plants. [ABSTRACT FROM AUTHOR]

Heat and drought are prominent abiotic stressors that limit crop productivity and yield, particularly concerning climate change; therefore, understanding the molecular mechanisms underlying plant stress responses is crucial for stress-tolerant crop production. This study conducted a transcriptomic analysis to elucidate how garlic (Allium sativum L.) responds to drought and heat stress conditions. Transcriptome libraries were generated to identify differentially expressed genes (DEGs) induced by drought and heat stresses. Functional classification and clustering analysis of DEGs revealed stress-specific gene expression patterns. Notably, cell wall-related genes were implicated in the drought response, whereas heat stress was associated with heat stress transcription factors and heat shock proteins. Our results provide essential information for future studies on stress tolerances in garlic. [ABSTRACT FROM AUTHOR]

Background: Sorghum is an economically significant staple food crop for more than half a billion people in developing nations, especially in arid and semiarid locations where drought stress is a significant limiting factor. Despite usually being regarded as tolerant, sorghum suffers severely from drought stress, which lowers its productivity and nutritional quality throughout its principal cultivation areas. Objective: Improvements in DNA fingerprinting by ISSRs, SSRs, and RAPD markers have also been employed in sorghum genetic modification (GMOs) to enhance the economic characteristics of this crop. Materials and methods: To provide a natural defence against pests, the most tolerant plants among the seven varieties of sorghum bicolour were selected and planted in the second season of 2020–2021 under treatment with two microorganisms, B. thuringiensis and P. aeruginosa. This study considered seven varieties of sorghum bicolour planted under 50% water deficiency in 2019–2020. Genetic variability analysis of sorghum genotypes was performed using seven Inter-Simple Sequence Repeat (ISSR) primers, six Simple Sequence Repeat (SSR) primers, and five Random Amplified Polymorphic DNA (RAPD) primers. Seven Sorghum bicolour accessions were collected from various regions of Egypt and their phylogenetic relationships were evaluated. Additionally, DNA fingerprinting and analyses of the genetic diversity and evolutionary linkages in the sorghum germplasm employed the (ISSR) molecular marker technique. Results and conclusion: The Fisher Least Significant difference test (LSD) at P < 0.05, based on RAPD, ISSR, and SSR markers demonstrated a significant connection. The findings demonstrated that 51 bands with a size range of 100–1500 bp and polymorphism percentage of 72.5% were created using five RAPD primers. Seven ISSR primers generated 45 bands With a 57.8(%) polymorphism percentage, ranging in size from 100 to 3000 bp. six SSR primers generated 28 bands with (67.86%) polymorphism percentage of 67.86 %, ranging in size from 100 to 1500 bp. Morphological characteristics and ISSR, SSR, and RAPD analyses were used to group the UPGMA Dendrogram into groups. Jaccard's coefficient was used to analyse the genetic similarity matrix. The maximum similarity was observed for ISSR between Hybrid Sh1 and Hybrid Sh306 (0.984%), SSR between Hybrid Sh306 and Sudan grass (0.964%), and RAPD between Giza 15 and Indian Millet (0.706%). The classification of sorghum germplasm, breeding initiatives, and conservation efforts rely heavily on the determination of the genetic diversity among sorghum species. Identification of genetic variants, morphological features, and genetic analysis of ISSR, SSR, and RAPD are useful techniques. These findings demonstrate a large ratio of variation in sorghum. This work could serve as a guide for future research on sorghum and aid in the understanding of species and breeding initiatives. [ABSTRACT FROM AUTHOR]

This article explores the use of a seed bio-priming technique to manage drought in mungbean crops. Drought stress can harm the growth and productivity of these plants, but biopriming, which involves coating seeds with beneficial microorganisms, has shown promise in reducing stress and improving crop yield. The application of beneficial bacteria to seeds stimulates plant growth and enhances nutrient absorption. This low-cost and environmentally friendly technique has the potential to promote growth, increase stress tolerance, and achieve desired crop yields. The article also discusses the impact of water stress on soil systems, particularly on soil microbes. Under drought conditions, soil microbes adjust their osmotic conditions to maintain their health, which includes various adaptations such as osmolyte accumulation and enzyme production. Plant growth promoting rhizobacteria (PGPR) is a sustainable alternative for mitigating drought stress in green gram crops. It helps improve physiological processes, root development, nutrient uptake, and overall crop establishment. However, the effectiveness of PGPR treatments may vary depending on factors such as plant species, environmental conditions, and the formulation/concentration of PGPR used. Further research is needed to optimize the selection and application of PGPR for different crops and drought scenarios. Bio-priming, a technique that combines biological and physiological aspects of seed treatment, has emerged as a sustainable method for improving mungbean production and controlling seed- and soil-borne pathogens. It has been shown to increase seed yield and nutrient uptake in mungbean under normal and [Extracted from the article]

This study aimed to determine a sainfoin variety best suited to the soil and weather conditions of the Great Lake Basin region inUlaangom soum of Uvs aimag (province). We carried out studies into five varieties of sainfoin, including Peschany 1251, Tashyl 3, Novosibirsky 1284, Shortandisky 83, and Mikhailovsky-5, which were compared with each other without irrigation trial. Sainfoin has a high resistance to cold winter conditions, high temperatures and and dry drought conditions. Sainfoin varieties growing in Mongolia are highly palatable perennial leguminous plants. According to the result of our research, sainfoin is well acclimatized to Uvs province's soil and weather conditions. The variety with the highest performance showing is Taskhyl 3, which was generated atthe Plant Research Center of Khakassia, a republic of Russia located in southern Siberia. [ABSTRACT FROM AUTHOR]

The article discusses a study on the phenotypic differentiation of Norway spruce seedlings under different water regimes. The researchers conducted an experiment with drought-stressed and well-watered seedlings from five provenances of Norway spruce. They measured various physiological traits and genotyped the seedlings. The study found that there was inconsistent phenotypic differentiation between the drought-stressed and control plants, with only three traits showing signs of selection under both treatments. The researchers emphasize the importance of considering the environmental setup of the experiment and highlight the need for common gardens in adaptation research. The article also includes a list of references related to genetic diversity, climate change, and adaptation in tree species, providing valuable information for researchers studying these topics. [Extracted from the article]

Withania somnifera plants were exposed to drought stress for 23 days. Relative water content (RWC), gaseous exchange, fluorescence parameters, and spectral reflectance changes were monitored under drought stress. Assimilation rate and RWC decreased by 81% and 65%, respectively, during drought exposure of 23 days. Photosynthetic reflectance index (PRI) and water index (WI) showed a decreasing pattern under drought stress and correlated with Amax and RWC. Anthocyanin reflectance index and anthocyanin content increased with drought stress. Similarly, rational among R727, R696, R770, and R731 reflects chlorophyll content and Chl a/b ratio and copes with actual chlorophyll content. Fluorescence changes showed the opening and closing of PSII reaction centers, while absorbance change at 830/875 nm showed activity and energy balance of PSI. Non-photochemical quenching increased under drought, which showed depoxydation of xanthine cycle pigment. Energy balance at the acceptor and donor side of PSI adjusted under drought stress by increasing electron carrying limitation at donor side. Energy balance between PSI and PSII is maintained by increasing cyclic electron flux under mild drought stress. Both protective mechanism depoxydation of xanthine cycle pigment and enhancement of cyclic electron flux reduced or diminished under severe drought stress. Decrease in leaf area and stomatal closure may cause a reduction in transpiration that results into loss of RWC and altered physiological processes. Since fluorescence, absorbance change and spectral reflectance are non-invasive measurements that may be used as indicators for assessing drought tolerance in medicinal plants. [ABSTRACT FROM AUTHOR]

The optimum grazing management practices to sustain or increase grassland resilience must be determined. The effects of the current and previous year's stocking densities (light, medium, and heavy stocking densities of 0.53, 0.89, and 1.24 AU ha−1, respectively) at the same stocking rate (35 AUD ha−1 yr−1) of yearling heifers (Bos taurus) grazing predominately blue grama [Bouteloua gracilis (Willd. ex Kunth) Lag. ex Griffiths] pastures on animal gains and pasture mass during the growing season were evaluated at New Mexico State University's Rex E. Kirksey Agricultural Science Center at Tucumcari, NM USA, over three years. Previous grazing management had no influence on animal performance (p > 0.14) but seasonal average daily gains and total gains ha−1 were decreased from low- to high-density grazing (p < 0.002). Nevertheless, for grassland resilience, when low followed either high or medium, blue grama mass increased compared to low following low. Alternatively, when medium followed high, blue grama mass was reduced, but when high followed either low or medium, forage mass numerically increased (p < 0.0117 for the previous × current year's stocking density interaction). Consequently, short-duration, high stocking density may be best using multiple pastures, each with the same grazing period each year to allow for a long-duration rest. Otherwise, during persistent drought, a longer-duration, medium stocking density could be used to allow for recovery. [ABSTRACT FROM AUTHOR]

Drought has severely affected the yield and quality of commercial crops. The BRI1 family plays an important role in plant response to drought stress, and BRL3 gene plays an important role in the study of drought in Arabidopsis thaliana. In this study, NtBRL3 was constructed as a vector and genetically transformed to obtain 'N. Tobacco K326' overexpression of NtBRL3. The enzyme activities of transgenic tobacco and wild-type tobacco were measured and transcriptome and metabolome analyses were performed. The results showed that the antioxidant enzymes of transgenic tobacco were more active under drought conditions, and 85 significantly differentially metabolites and 106 significantly differentially expressed genes were identified in the metabolome and transcriptome analyses, respectively. Transgenic tobacco NtBRL3ox demonstrated an excessive accumulation of droughtrelated metabolites, sugars such as sucrose and maltotetraose, and amino acids such as proline, compared with WT. We discovered drought-related differential genes in the root transcriptome, among which LOX6, RD22, WSD1, CCD8, and UGT were key genes which play an important role in plant response to drought stress. Our results demonstrate that NtBRL3 overexpression in K326 enhances drought resistance in transgenic tobacco. [ABSTRACT FROM AUTHOR]

Tomato (Solanum lycopersicum) is one of the most important vegetable crops in the world and abiotic stresses often cause serious problems in tomato production. It is thus important to identify new regulators in stress response and to devise new approaches to promote stress tolerance in tomato. Previous studies have shown that small secreted peptides (SSPs) are important signal molecules regulating plant growth and stress response by mediating intercellular communication. However, little is known about tomato SSPs, especially their roles in responding to abiotic stresses. Here we report the identification of 1,050 putative SSPs in the tomato genome, 557 of which were classified into 38 known SSP families based on their conserved domains. GO and transcriptome analyses revealed that a large proportion of SlSSPs might be involved in abiotic stress response. Further analysis indicated that stress response related cis-elements were present on the SlCEP promotors and a number of SlCEPs were significantly upregulated by drought treatments. Among the drought-inducible SlCEPs, SlCEP10 and SlCEP11b were selected for further analysis via exogenous application of synthetic peptides. The results showed that treatments with both SlCEP10 and SlCEP11b peptides enhanced tomato drought stress tolerance, indicating the potential roles of SlSSPs in abiotic stress response. [ABSTRACT FROM AUTHOR]

N6-methylated adenine (m6A) is an emerging epigenetic marker in eukaryotic organisms that plays an important role in biological functions and in enriching genetic information.m6A exerts these functions via the dynamic interplay among m6A writers, erasers, and readers. However, little is known about the underlying mechanisms of m6A in plant growth and stress responses. Here, we identified 276 masked m6A regulators from nine Rosaceae species (Pyrus bretschneideri, Pyrus betulifolia, Pyrus communis, Malus domestica, Fragaria vesca, Prunus avium, Prunus mume, Prunus persica, and Rubus occidentalis). We classified and named these genes in more detail based on phylogenetic and synteny analysis. The expansion ofm6A regulators in Maloideae was dated back to the recent whole-genome duplication (WGD) in Rosaceae. Based on the expression pattern analysis and gene structure analysis of m6A regulators, m6A was shown to be a significant factor in regulating plant development and resistance. In addition, PbrMTA1-silenced pear plants displayed significantly reduced drought tolerance and chlorophyll content, as well as increased electrolyte leakage and concentrations of malondialdehyde and H2O2. [ABSTRACT FROM AUTHOR]

Drought stress severely impairs common bean production. For facilitating drought-resistance breeding in common bean, molecular markers were identified in a genome-wide level marker-trait association study. A panel of 210 common bean accessions showed large variation in 11 agronomic traits at the adult stage (plant height, pod number per plant, seed number per pod, seed number per plant, seed yield per plant, pod length, harvest index, pod harvest index, days to maturity, hundred-seed weight, and seed yield) under two water conditions. The coefficient of variation ranged from 6.21% for pod harvest index to 51.00% for seed number per plant under well-watered conditions, and from 4.05% for days to maturity to 40.72% for seed number per plant under drought stress. In a genome-wide association study, 119 quantitative-trait loci were associated with drought resistance, including 41 adjacent to known loci. Among these loci, 12 were found to be associated with at least two traits. Three major loci were identified at Pv01 and Pv02. A set of candidate genes were found that encode MYBs, AREBs, WKRYs, and protein kinases. These results reveal promising alleles that control drought resistance, shedding light on the genetic basis of drought resistance and accelerating future efforts for drought resistance improvement in common bean. [ABSTRACT FROM AUTHOR]

Root architecture development, an agronomic trait that influences crop yield, is regulated by multiple plant hormones. Abscisic acid (ABA) is a stress hormone that responds to multiple stresses, including salt, drought, and cold stress, and modulates various aspects of plant growth and development. In recent years, it has been found that ABA synthesized under mild stress or well-watered conditions can support plant growth and stress resistance by positively regulating root architecture development. In this review, we summarize the molecular, cellular, and organismal basis of ABA homeostasis in the root and how ABA signaling affects root architecture development both as an inhibitor and as an activator. We discuss the implications of these studies and the potential for exploiting the components of ABA signaling in designing crop plants with improved root system development and stress resistance. [ABSTRACT FROM AUTHOR]

Introduction The present research on Lycium depressum stocks aims to study the vegetative responses (leaf area, leaf specific weight, leaf specific area, dry weight ratio of root to shoot, dry weight of leaf, stem, and root) of the pasture shrub of Kam Tigh against drought stress and the effect of soil amendment on these responses. Materials and methods The experiment was conducted in a factorial design based on a completely randomized design, including the main irrigation treatment at four levels (100, 75, 50, and 25% of crop capacity) and subtreatment of soil conditioners under semi-controlled greenhouse conditions. The experiment involved five repetitions and 160 pots for each combined irrigation and soil amendment treatment. Subtreatments of soil conditioners, including Stacosorb hydrogel, were added at 3 grams per kilogram of soil in each pot in the lower part of the plant roots. Mineral Zeolite in 8 grams per pot was placed in the lower part of the plant roots. Nitrobacter was added in the amount of 3 cc in each pot in the upper root area of the plant. Mycorrhiza at 10 grams per pot was added to the lower plant roots. Results and discussion Generally, a significant difference (p<0.05) was observed in all irrigation levels between the treatments in each soil amendment material. In zeolite with mycorrhiza, the highest stem dry weight and leaf-specific weight were obtained at a 50% irrigation level. With the increase in leaf-specific gravity and drought stress, plant dry weight increased, and proline content decreased in Nitrobacter and mycorrhizal treatment, which differed from the treatment. Measurements of leaf area revealed that leaf area decreased from 1450 mm2 in 100% and 75% irrigation to 900 mm2 in 25% irrigation. This indicated the impact of drought stress on the leaf area. The highest specific weight of leaves at 25% irrigation was related to Nitrobacter with mycorrhiza. This modifier increased the specific weight of leaves from 0.0025 g/m2 at 100% irrigation level to 0.0028 g/m2 at 25% irrigation level. Leaf surface area in Nitrobacter treatment with mycorrhiza during 100% irrigation decreased from 400 mm2/g to 350 mm2/g during 25% irrigation. In hydrogel treatment without mycorrhiza, the dry weight ratio of root to shoot at 100% irrigation level declined from 2 grams to 1.4 grams in 25% irrigation. The dry weight of the leaf decreased from 1.4 g in 100% irrigation to 1.3 g in 25% irrigation. Conclusions Biofertilizers enhance plant resistance to drought stress by improving vegetative characteristics. Nitrobacter treatments without mycorrhiza, hydrogel, and zeolite with mycorrhiza are recommended for planting this plant due to improved growing conditions. Since the Kam Tig plant is considered a medicinal plant, it can be used as a soil conditioner in the pharmaceutical and medical industries. This will enable better cultivation of the species. All organizations related to the cultivation of Kam Tig species can use the results of this research to enhance cultivation projects. [ABSTRACT FROM AUTHOR]

Small ubiquitin-like modifier (SUMO) E3 ligases that facilitate the conjugation of SUMO proteins to target substrates contain an SP-RING domain which is like the RING domain found in ubiquitin E3 ligases. In this study, we isolated and characterized the Oryza sativa protein inhibitor of activated STAT like1 (OsPIAL1) containing SP-RING domains, as the rice homolog of Arabidopsis PIALs. OsPIAL1 interacts with OsSUMO proteins but does not interact with rice SUMO-conjugating enzymes (OsSCEs). An analysis of transgenic rice plant shows that OsPIAL1 is involved in SUMO conjugation to SCEs but not in SUMO conjugation to substrates. In addition, this OsPIAL1 activity requires drought stress conditions. Expression profiles show that the OsPIAL1 gene is induced by only drought stress in the leaves, whereas it is repressed by ABA and abiotic stresses in the roots. Salt stress leads to the fastest decrease in OsPIAL1 transcripts in the roots. Furthermore, the stress experiments indicate that the transgenic rice plants overexpressing OsPIAL1 exhibit a drought stress-tolerant phenotype but a salt stress hypersensitive phenotype. Our results and those from Arabidopsis pial mutants suggest that PIALs act as a positive regulator in the drought stress response but as a negative regulator in the salt stress response. [ABSTRACT FROM AUTHOR]

Background: The plant-growth-promoting rhizobacterium Tsukamurella tyrosinosolvens is a rare strain of actinomycete, in order to recognize and expand the ecological functions of rare actinomycetes. Methods: In this experiment, we studied the effect of Tsukamurella tyrosinosolvens P9 on the drought resistance of peanut by inoculating peanut seedlings in pots and measuring the growth and physiological indicators of peanut under drought stress and re-watering conditions. Results: The results showed that during drought stress, the relative water content of the soil and leaves, chlorophyll content, and stomatal length, width, and aperture were significantly decreased while the levels of malondialdehyde (MDA), H2O2 and stomatal density were significantly increased. Peanut growth was also inhibited. However, inoculation with the P9 strain significantly promoted the growth of peanut under drought stress as plant height, fresh weight, root length and root weight were significantly higher compared with the uninoculated drought stress group. In addition, in P9-inoculated plants, the water and chlorophyll contents were significantly higher and the activities of the antioxidant enzymes CAT and SOD were significantly increased (except during the six days of drought treatment). While the stomatal length, width, and aperture were improved, the levels of MDA and H2O2 were significantly decreased. NBT staining showed that inoculation with P9 reduced O2− accumulation under stress. After re-watering, the physiological indexes of inoculated plants recovered more quickly and grew better. Conclusions: The results showed that T. tyrosinosolvens P9 enhanced drought resistance and improves peanut growth by increasing leaf water content, increasing photosynthesis, regulating stomatal closure, and improving antioxidant enzyme activity. [ABSTRACT FROM AUTHOR]

Objective: As a critical limitation of plant growing, drought stress has always received a lot of attention from botanical researchers. This study intends to investigate the role of salicylic acid and the Mycorrhiza and Azotobacter bio-fertilizer on Satureja hortensis L. under drought stress. Materials and Methods: Salicylic acid and bio-fertilizers have been shown to improve drought tolerance in growing plants. To evaluate the synergistic effect of salicylic acid, Azotobacter chroococcum bacteria, and arbuscular mycorrhizal fungi under drought stress (-3.5 atm: W1), (-6.5 atm: W2), and (-10 atm: W3), a 2-year (2016 to 2018) field experiment was organized based on split-plot factorial statistical in a randomized complete block design, with three replicates. Results: The main findings of this study showed that the combinable use of bio-fertilizers and salicylic acid diminished the disadvantageous effects of drought stress. Co-application of bio-fertilizers and salicylic acid significantly increased chlorophyll a and b (22% and 31.5%), carotenoid (30.7%) contents, aerial fresh (38.3%) and dry (64.1%) weights, root fresh (55.8%), and dry (45%) weights, auxin (15%), percentage of essential oil (30.7%) in S. hortensis while it decreased the proline content (48.8%) under severe stress as compared to the control groups, which confirmed the efficacy of this approach and its role in drought tolerance. Conclusion: The results demonstrated that this new suggested treatment could effectively alleviate drought stress symptoms and improve S. hortensis growth under spreading drought conditions and limited water resources. [ABSTRACT FROM AUTHOR]

As sessile organisms, plants possess a complex system to cope with environmental changes. Ca2+ functions as a vital second messenger in the stress signaling of plants, and the CBL-interacting protein kinases (CIPKs) serve as essential elements in the plant Ca2+ signaling pathway. In this study, calcineurin B-like protein-interacting protein kinase 26 (BdCIPK26) from Brachypodium distachyon was characterized. Overexpression of BdCIPK26 enhanced tolerance to drought and salt stress of transgenic plants. Further investigations revealed that BdCIPK26 participated in abscisic acid (ABA) signaling, conferred hypersensitivity to exogenous ABA in transgenic plants, and promoted endogenous ABA biosynthesis. Moreover, BdCIPK26 was found to maintain ROS homeostasis in plants under stress conditions. Therefore, this study indicates that BdCIPK26 functions as a positive regulator in drought and salt stress response. [ABSTRACT FROM AUTHOR]