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Fructan 1-exohydrolase (1-FEH) is one of the major enzymes in water-soluble carbohydrate (WSC) remobilisation for grains in wheat. We investigated the functional role of 1-FEH w1, w2, and w3 isoforms in WSC remobilisation under post-anthesis water deficit using mutation lines derived from the Australian wheat variety Chara. F1 seeds, developed by backcrossing the 1-FEH w1, w2, and w3 mutation lines with Chara, were genotyped using the Infinium 90K SNP iSelect platform to characterise the mutated region. Putative deletions were identified in FEH mutation lines encompassing the FEH genomic regions. Mapping analysis demonstrated that mutations affected significantly longer regions than the target FEH gene regions. Functional roles of the non-target genes were carried out utilising bioinformatics and confirmed that the non-target genes were unlikely to confound the effects considered to be due to the influence of 1-FEH gene functions. Glasshouse experiments revealed that the 1-FEH w3 mutation line had a slower degradation and remobilisation of fructans than the 1-FEH w2 and w1 mutation lines and Chara, which reduced grain filling and grain yield. Thus, 1-FEH w3 plays a vital role in reducing yield loss under drought. This insight into the distinct role of the 1-FEH isoforms provides new gene targets for water-deficit-tolerant wheat breeding.

Introduction Stevia (Stevia rebaudiana) is one of the medicinal plants of the Asteraceae family that contains natural compounds, especially stevioside and ribaodioside A, which are estimated to be 150 to 400 times sweeter than sucrose. Plants are exposed to various environmental stresses during growth and development under natural and agricultural conditions. Among these, drought is one the most severe environmental stresses affecting plant productivity. About 80–95% of the fresh biomass of the plant body is comprised of water, which plays a vital role in various physiological processes including many aspects of plant growth, development, and metabolism. Stevia is susceptible to various environmental stresses but the major effects are contributed by drought. Today, the fungal species Stevia rebaudiana is used as a biofertilizer and increases the production of secondary metabolites of economically valuable plants and also increases the growth and seed production of many plants. This fungal endophyte produces a significant amount of acid phosphatase for mobility in a wide range of insoluble or complex forms of phosphate, enabling the host plant to have adequate access to inactive phosphorus reserves in the soil. However, medicinal plants that are cultivated have often been reported to have lower abundance of arbuscular mycorrhizal fungi in the rhizosphere, which significantly reduces plant survival. Considering the coexistence role of mycorrhizal fungi in modulating the effects of drought stress, the aim of this study was to investigate the morphological, physiological and biochemical traits of stevia in response to the effects of mycorrhizal inoculation and drought stress. Materials and Methods This experiment was conducted to investigate the effect of P. indica endophytic fungus under water stress conditions on vegetative characteristics, physiological parameters and micronutrients of stevia. A factorial experiment was employed based a completely randomized design with four replications in the research greenhouse of Islamic Azad University, Mahabad Branch in 2017. The first factor was drought stress at four levels (25, 45, 60 and 80% of field capacity) and the second factor was inoculation of seedlings with fungus at two levels (no inoculation and inoculation with P. indica). Water stress was applied based on a combination of plant appearance symptoms (no wilting to severe wilting) and soil moisture. Investigated traits included root colonization, dry weight, leaf number, plant height, stem diameter, chlorophyll a, b, total chlorophyll, carotenoids, proline, soluble sugars, antioxidant power and micronutrients including copper, iron, zinc and manganese. To analyze the data variance, SAS 9.1 statistical software was used to analyze the variance of the data. Results and Discussion The results showed that the evaluated traits in the present study were affected by the main treatments of fungus and drought stress. Seedlings inoculated with P. indica endophytic fungi had the highest percentage of root colonization, growth parameters, photosynthetic pigment content, soluble compounds and micronutrients compared to no inoculation. Drought stress increased soluble sugars, proline content and antioxidant power of stevia leaves and decreased the other traits by increasing the stress level from 25 to 80%. The highest rate of root colonization (26.90%), stem diameter (3.21 mm) and carotenoid content (1.71 μg/ml) was observed in the treatment of plant inoculation with fungi and 25% drought stress. While the highest antioxidant power was found in the treatment of plant inoculation with fungi and 80% drought stress. According to the results of the present study, use of P. indica fungus had the most positive effect on the quantitative and qualitative characteristics of stevia medicinal plant compared to no fungus inoculation. Conclusion This study showed the positive effect of P. indica endophyte inoculation on quantitative and qualitative characteristics of root colonization, dry weight, number of leaves, plant height, stem diameter, chlorophyll a, b, total chlorophyll, carotenoids, proline, soluble sugars, antioxidant power and The micronutrients of calcium, iron, zinc and manganese showed stevia, and drought stress reduced the studied traits except for proline content, soluble sugars and antioxidant power. Inoculation of stevia seedlings with P. indica endophytic fungi at drought stress levels had the highest rate of root colonization, stem diameter, carotenoid content and antioxidant power compared to non-fungal inoculation. Therefore, due to the effect of biological compounds of natural origin and the production of plants with healthier active secondary compounds, the use of P. indica endophytic fungi can be recommended.

Abstract Freshwater is an essential resource used to generate electricity at coal-fired power plants. Previous literature has shown that a few states in Malaysia will face a high risk of water stress. Hence, coal-fired power plants located at risk states are exposed to potential water risk. This study aims (i) to determine the operational blue water footprint at coal-fired power plant from 2009 until 2020; (ii) to assess the water stress index at Perak, Negeri Sembilan and Johor; and (iii) to compare the water deficit impact across three states. This study accounted the operational water footprint using Water Footprint Assessment Global Manual. The study boundary focuses on water consumption of generating electricity at operational level. The water stress index was assessed based on ratio of water demand and water availability at Perak, Negeri Sembilan and Johor watershed. Next water deficit impact was determined to compare the impact of operational blue water footprint on local water resources. Data for this study were collected from the state’s water authority, published literature, national reports, and statistics. Result of this study found the average operational blue water footprint recorded by coal-fired power plant located at Perak is 0.11 m3/MWh followed 0.09 m3/MWh (Johor) and 0.04 m3/MWh (Negeri Sembilan). Water stress index at Perak and Negeri Sembilan shows moderate water stress, whereas Johor indicates low water stress index. The water deficit result shows Perak has the highest total water deficit at 12,542,824 m3H2Oeqn from 2009 to 2020. This is due to moderate water stress condition at Perak and the total blue water footprint of coal-fired power plant at Perak is 67% and 42% more as compared to Negeri Sembilan and Johor, respectively. The result from this study is useful in enhancing understanding of water consumption pattern at coal-fired power plant and its impact on state’s water resources for future electricity scenarios.

This investigation was aimed to study the response of potato plants to water deficit and exogenous application of salicylic acid (SA) and glycine betaine (GB). Potato cultivars, Spirit, Born, Arinda and Banba were experienced under two irrigation regimes, 30 and 60 % depletion of available soil water, and two concentrations of both SA (0.5 and 1.0 mM) and GB (1.0 and 2.0 mM) additionally the control (0.0 mM SA and GB). Gas exchanges, proline content (Pro), root volume (RV), root/shoot ratio (R/S), plant dry mass (PDM), number tuber (NT) and yield of potato cultivars were measured. With the exception of R/S, water deficit led to notable decreases in gas exchanges, RV, PDM, NT and yield of potato cultivars and increases in Pro content. Foliar application of SA and GB resulted in significant increases in photosynthesis (Photo), carbon dioxide concentration in the sub-stomatal chamber (Ci), stomatal conductance (Gs), Pro, PDM and yield in some levels of SA and GB; the level of the increases appeared more when potato plants were grown under water deficit conditions. All the overhead effects supported PDM and yield of potato cultivars to increase by exogenous application of SA and GB and directed to the assumption that water deficit converted harmful effects on potato cultivars could be released by exogenous applied SA and GB.

Climate scenarios in the medium and long term (2010-2070) foresee increased summer rainfall for Uruguay and the region, with increased water deficits and excess episodes. Although at the international level irrigation in viticulture has a long experience and tradition, at the local level (Uruguay), only 10% of the vineyard surface area implements a fixed or complementary system for water supply in their crops. This work aimed to model the crop water requirements for a vineyard in southern Uruguay based on pedo-climatic variables. In addition, the plant response to controlled deficit irrigation was evaluated in two consecutive seasons. The experiment was conducted in a 1.1 ha commercial vineyard in Canelones, Uruguay (34°36'S, 56°14W), during two successive seasons (2020-2021). The additional irrigation (I) treatment was compared against a control (C) without irrigation. A controlled water deficit was established from flowering to harvest. The adjustment in the demand was made as a function of a percentage of crop evapotranspiration. The Kc of the crop was estimated using digital tools. The simulation of the water balance made it possible to evaluate the vineyard water needs. Plants subjected to controlled deficit irrigation showed higher vegetative growth, positively impacting yield and the accumulation of sugars and anthocyanins in the berry. Based on our results, a supplementary water supply, at the right doses and time, allows us to face water deficit situations, positively impacting the productive and economic variables. Knowing the variability in a vineyard is necessary to achieve proper irrigation scheduling and optimize water use. New technologies applied to irrigation are an opportunity for winegrowers to obtain more sustainable vineyards and production.

Sweet sorghum (Sorghum bicolor [L.] Moench) is a plant that can be an alternative for the production of bioethanol in semi-arid regions. The objective of this work was to evaluate sweet sorghum 'BRS 506' under salt and water stress. The experimental design was in randomized blocks, in a factorial scheme (4x4), with the first factor referring to the electrical conductivities of the irrigation water (1.5; 3.0; 4.5; and 6.0 dS m-1) and the second refers to irrigation depths (53, 67, 85 and 95% of crop evapotranspiration). Gas exchange, leaf water status, leaf sugars and plant growth were evaluated. Salt and water stress cause negative effects on the growth of sweet sorghum 'BRS 506'. Salt stress causes disturbances in gas exchange and sugar levels. Sweet sorghum 'BRS 506' is tolerant to combined salt and water stress.

IntroductionThe aim of our study was to examine how silicon regulates water uptake by oilseed rape roots under drought conditions and which components of the antioxidant system take part in alleviating stress-induced ROS generation in the roots.MethodsThe study analyzed mainly the changes in the roots and also some changes in the leaves of oilseed rape plants, including total silicon content, relative water content, osmotic potential, stomatal conductance, abscisic acid level, the accumulation of BnPIP1, BnPIP2-1-7 and BnTIP1 aquaporins, and the activity of antioxidant enzymes.Results and discussionIt was shown that plants growing in well-watered conditions and supplemented with silicon accumulate smaller amounts of this element in the roots and also have higher relative water content in the leaves compared to the control plants. It was demonstrated for the first time that BnTIP1 accumulation in oilseed rape roots is reduced under drought compared to wellwatered plants, and that this effect is intensified in plants supplemented with silicon. In addition, it was shown that silicon supplementation of oilseed rape increases catalase activity in the roots, which correlates with their high metabolic activity under drought and ultimately stimulates their growth. It was shown that silicon improves water balance in oilseed rape plants subjected to drought stress, and that an important role in these processes is played by tonoplast aquaporins. In addition, it was demonstrated that silicon reduces oxidative stress in roots under drought conditions by increasing the activity of catalase.

Common bean (Phaseolus vulgaris) can efficiently fix atmospheric nitrogen when associated with Rhizobia. However, drought stress impairs plant metabolic processes, especially the biological nitrogen fixation (BNF). Here, we assessed transcriptional responses in nodules of two common bean genotypes to drought stress under BNF reliance. The RNA-Seq analysis yielded a total of 81,489,262 and 72,497,478 high quality reads for Negro Argel and BAT 477 genotypes, respectively. The reads were mapped to the Phaseolus vulgaris reference genome and expression analysis identified 145 and 1451 differentially expressed genes (DEGs) for Negro Argel and BAT 477 genotypes, respectively. Although BAT 477 had more DEGs, both genotypes shared certain drought-responsive genes, including an up-regulated heat shock protein (HSP) and a down-regulated peroxidase, indicating shared pathways activated during drought in nodule tissue. Functional analysis using MapMan software highlighted the up-regulation of genes involved in abiotic stress responses, such as HSPs and specific transcription factors (TFs), in both genotypes. There was a significant down-regulation in metabolic pathways related to antioxidant protection, hormone signaling, metabolism, and transcriptional regulation. To validate these findings, we conducted RT-qPCR experiments for ten DEGs in nodules from both genotypes, for which the expression profile was confirmed, thus reinforcing their functional relevance in the nodule responses to drought stress during BNF. BAT 477 genotype exhibited more pronounced response to drought, characterized by a high number of DEGs. The strong down-regulation of DEGs leads to transcriptional disturbances in several pathways related to stress acclimation such as hormone and antioxidant metabolism. Additionally, we identified several genes that are known to play key roles in enhancing drought tolerance, such as HSPs and crucial TFs. Our results provide new insights into the transcriptional responses in root-nodules, an underexplored tissue of plants mainly under drought conditions. This research paves the way for potential improvements in plant-bacteria interactions, contributing to common bean adaptations in the face of challenging environmental conditions.

Abstract One of the major challenges for effective agricultural activity monitoring systems is defining robust indicators of spatial and temporal variability for the main risk factors associated with crop production. In this context, this study aimed to analyze the potential of the Temperature-Vegetation Dryness Index (TVDI), obtained by terrestrial and orbital sensors from soybean production areas in southern Brazil, in generating spatial and temporal patterns of the main risk factor, surface moisture, to be incorporated in operational agricultural monitoring systems. For this purpose, MODIS Terra and Landsat-8 OLI/TIRS sensor images were used, as well as data from surface positioned sensors to serve as a reference. The study area encompassed one soybean crop area, soybean mapped crop areas near the experimental area, and the municipality of Carazinho-RS. The experimental area was analyzed during the soybean growing season. As the TVDI data estimated by OLI/TIRS and MODIS sensors were coherent and robust, both sensors can be used in conjunction for agricultural risk monitoring. Its main features are continuous monitoring of large production regions by TVDIMODIS and spatial distribution detailing by TVDIOLI/TIRS in critical periods to water deficit.

A split-plot experiment was conducted based on a randomized complete block design with four replications in two years to study the effect of melatonin on the biochemical properties and the gene expression related to antioxidant enzyme activity in bread wheat. Irrigation levels (normal (FC = 80%)), mild stress (FC = 60%), and severe stress (FC = 40%)) were assigned to the main plots, and melatonin foliar applications (zero, 50, 100, 150, and 200 μM) were assigned to Subplots. Results showed that, with the intensification of water stress, the 1000 kernel weight decreased, and the activity of ascorbate peroxidase enzyme and flavonoid content increased. Also, the level of 100 μM melatonin had the highest 1000 kernel weight, flavonoid content, and ascorbate peroxidase enzyme activity. In this study, the highest number of grains per spike, biological yield, grain yield, chlorophyll a, chlorophyll b, carotenoids, and the lowest amount of malondialdehyde recorded for foliar treatment with 50 μM of melatonin under normal irrigation conditions and the highest proline content, total phenol, superoxide dismutase, and catalase were allocated to the 100 μM melatonin foliar treatment under severe water stress conditions. The synergistic effect of water deficit stress and melatonin foliar application increased the activity and expression level of genes related to antioxidant enzymes. So, the content of superoxide dismutase (21.30% and 65.16% respectively) and catalase (50.60% and 54.44% respectively) enzyme activity increased significantly under 100- and 150-mM melatonin foliar application in water severe water stress compared to the corresponding control treatment. Furthermore, mentioned melatonin levels increased the gene expression levels of superoxide dismutase (16.67% and 38.19% respectively), ascorbate peroxides (73.76% and 47.57% respectively), polyphenol oxidase (39.32 and 51.15%) and catalase (39.95% and 50.0% respectively) under an extreme water shortage compared with corresponding control treatment. In general, the application of 100- and 150-mM melatonin induced resistance to water deficit stress in wheat by increasing the expression of antioxidant genes.

Abstract The objective of this work was to evaluate biomass accumulation and photosynthesis in mangabeira, in response to water deficit and to successive soil drying and wetting cycles. Seedlings were grown in pots and subjected to the three following water regimes: soil at 35, 70, and 100% of field capacity (FC), followed by a drying-down period until photosynthesis (measured weekly) was close to zero. Then, the seedlings were rewatered until completing four drying-wetting cycles. The control treatment was a permanently well-irrigated soil. There was a decline in biomass accumulation under water deficit conditions. Photosynthesis responded to soil rewatering only at 70 and 100% FC and was null at 35% FC. The elapsed time for photosynthesis to reach a null value after rewatering increases with successive drying-wetting cycles. In soil at 100% FC, for photosynthesis to approach zero, it takes five weeks in the first and eight weeks in the last rewatering cycle. Photosynthesis improves with progressive drying-wetting cycles, particularly in soil at 100% FC. The pre-acclimation of mangabeira to drying-wetting cycles should be considered before transplanting the seedlings in the field, and pre-acclimation should be carried out initially with soil at its FC.

Sugarcane yields have steadily declined across southern Africa for the past 25 years and, despite research into the causes, there has been limited progress in addressing these trends. This study developed a methodology of assessing yield declines and performed a yield gap analysis to assess and develop recommendations to assist in combating yield declines and offering potential safeguards for the sugarcane industry against climatic extremes. Mill areas from South Africa, eSwatini, Malawi and Tanzania were selected, providing a diversity of regional hydroclimatic conditions and sugarcane agronomic management approaches. Using the AquaCrop crop model, maximum potential yields and yield gaps were simulated based on observed climate and yield data spanning 25 years. Results show that yields are declining for the mill areas in South Africa, Malawi and Tanzania, resulting in increased yield gaps, whilst yields are stagnant in eSwatini resulting in relatively fixed yield gaps. Yield gaps remained high across all six mill areas, suggesting that they remain vulnerable and exposed to climatic extremes. Modelling results suggest that these yield trends, including yield gaps, are primarily attributed to existing crop management approaches as opposed to the climatic regimes in these areas. Recommendations include several solutions that could result in an immediate response and reduce yield gaps while increasing harvestable yields. Such measures include increasing technology transfer and agronomic management education to small-scale outgrowers, adopting drought-resistant, high-yielding sugarcane varieties, contouring and mulching, improving soil structural properties and minimizing in-field traffic. The study concludes that if sugarcane growers are to withstand the effects of extreme climatic events, they have to consider shifting crop management approaches and be proactively included in related research.

Premise of research. Maternal environment can influence the seed ecophysiology, for example, of species that produce fruits in different seasons. Due to seasonal variations in environmental factors, differences in germination responses, seed traits, and seedling size may occur. Using seeds of Piper umbellatum produced in the same population in both the rainy and dry seasons, we evaluated the effects of temperature variations and water availability on germination parameters, root growth, and seed traits. Methodology. Eight temperature treatments (15°C, 20°C, 23°C, 25°C, 28°C, 30°C, 35°C, and alternation between 30°C and 20°C) and four water potentials (0, −0.3, −0.6, and −1.2 MPa) were performed. The following parameters were analyzed: germination onset, germination percentage (G%), mean germination time (MGT), root elongation, seed longevity during ex situ storage, and dry mass of seeds. Pivotal results. All parameters analyzed differed according to the seed production period. The rainy-season seeds had greater germinability and longevity, as they started to germinate first with higher G% and lower MGT values than the dry-season seeds, which were more sensitive to the effects of water deficit in relation to germination parameters. Dry-season seeds had higher dry mass, and their seedlings had greater root growth than those from rainy-season seeds. This balance between germination parameters and traits of seeds and seedlings reflects the existence of an intergenerational memory of stress. Conclusions. The maternal environment during the seed production period influenced germination responses, seed traits, and root growth. The first stages of plant development can be strongly impacted by climate change, and the responses to these changes can vary according to the period of seed production in the same species. [ABSTRACT FROM AUTHOR]

Drought stress poses a considerable challenge to agriculture sustainability in arid regions. Water scarcity severely affects date palm growth and productivity in these regions. However, as water resources become increasingly scarce in arid regions, understanding the drought tolerance of date palm cultivars becomes imperative for developing drought-resistant cultivars and optimizing irrigation water usage for sustainable agriculture. This research examines the impact of different drought stress levels based on evapotranspiration (ETc), i.e., 40%, 60%, 80%, and 100% ETc, and time intervals (0, 6, 12, 18, and 24 months) on leaf growth, net photosynthesis, chlorophyll a and b content, and leaf relative water content (LRWC) of four prominent date palm cultivars, Khalas, Barhee, Hilali, and Ashrasee. In addition, the study also examines the effects of drought stress on dry weight, potassium and calcium content of leaf, stem, and root, and proline content in fresh leaves of these four cultivars. A solar-powered drip irrigation system with automated time-based irrigation scheduling was used to accurately control the irrigation water amount. To real-time estimate ETc in the study area, meteorological data were collected using a cloud-based IoT system. The findings of this study revealed that severe drought conditions (40 and 60 % ETc) significantly reduced leaf growth, plant dry biomass, and physiological and biochemical attributes; however, date palm cultivars can be grown under moderate drought conditions (80% ETc) with minimal effect on phenotypic, physiological, and biochemical traits to conserve water. The study also revealed that the drought-related characteristics decreased gradually with an increase in water stress time over 24 months. Comparing the date palm cultivars revealed that the Khalas and Barhee cultivars are more drought-tolerant, followed by Hilali, while Ashrasee is susceptible. The study elucidated a water conservation strategy employed in response to drought-induced stress based on the physiological and morphological parameters of date palm cultivars. It provides valuable insights into irrigation practices in arid regions. However, future studies can be focused on other nondestructive innovative techniques such as pulse-amplitude-modulation (PAM) fluorimetry, infrared radiation (IR), and video imaging system (VIS) methods to identify drought stress in date palms. [ABSTRACT FROM AUTHOR]

Drought resistance is essential for plant production under water‐limiting environments. Abscisic acid (ABA) plays a critical role in stomata but its impact on hydraulic function beyond the stomata is far less studied. We selected genotypes differing in their ability to accumulate ABA to investigate its role in drought‐induced dysfunction. All genotypes exhibited similar leaf and stem embolism resistance regardless of differences in ABA levels. Their leaf hydraulic resistance was also similar. Differences were only observed between the two extreme genotypes: sitiens (sit; a strong ABA‐deficient mutant) and sp12 (a transgenic line that constitutively overaccumulates ABA), where the water potential inducing 50% embolism was 0.25 MPa lower in sp12 than in sit. Maximum stomatal and minimum leaf conductances were considerably lower in plants with higher ABA (wild type [WT] and sp12) than in ABA‐deficient mutants. Variations in gas exchange across genotypes were associated with ABA levels and differences in stomatal density and size. The lower water loss in plants with higher ABA meant that lethal water potentials associated with embolism occurred later during drought in sp12 plants, followed by WT, and then by the ABA‐deficient mutants. Therefore, the primary pathway by which ABA enhances drought resistance is via declines in water loss, which delays dehydration and hydraulic dysfunction. Summary statement: The impact of abscisic acid on the drought tolerance of young plants of tomato is essentially associated with stomatal function, and not with xylem resistance to embolism. [ABSTRACT FROM AUTHOR]

Tetragonia tetragonoides (Pall.) Kuntze (Aizoaceae, 2n = 2x = 32), a vegetable used for both food and medicine, is a halophyte that is widely distributed in the coastal areas of the tropics and subtropics. Saline–alkaline soils and drought stress are two major abiotic stressors that significantly affect the distribution of tropical coastal plants. Abscisic acid-, stress-, and ripening-induced (ASR) proteins belong to a family of plant-specific, small, and hydrophilic proteins with important roles in plant development, growth, and abiotic stress responses. Here, we characterized the ASR gene family from T. tetragonoides, which contained 13 paralogous genes, and divided TtASRs into two subfamilies based on the phylogenetic tree. The TtASR genes were located on two chromosomes, and segmental duplication events were illustrated as the main duplication method. Additionally, the expression levels of TtASRs were induced by multiple abiotic stressors, indicating that this gene family could participate widely in the response to stress. Furthermore, several TtASR genes were cloned and functionally identified using a yeast expression system. Our results indicate that TtASRs play important roles in T. tetragonoides' responses to saline–alkaline soils and drought stress. These findings not only increase our understanding of the role ASRs play in mediating halophyte adaptation to extreme environments but also improve our knowledge of plant ASR protein evolution. [ABSTRACT FROM AUTHOR]

Water conservation is one of the major challenges encountered by terrestrial arthropods; species inhabiting dry forests are hypothesized to have adapted to dry conditions. Tityus pusillus Pocock, 1893 is one of the most abundant scorpion species in northeastern Brazil, occurring in dry and tropical rainforests. Considering the wide distribution of T. pusillus, we aimed to investigate differences in desiccation resistance between populations originating from the Atlantic rainforest and the Caatinga dry forest. In this study, 40 individuals of T. pusillus from each of the two ecosystems were used. The two groups were separated into control and treatment groups (individuals without a water supply). Scorpions from the Atlantic rainforest had a shorter lifespan than those from the Caatinga dry forest, both in the control and treatment groups. However, the weight loss rate was higher in scorpions from the Caatinga dry forest than those from the Atlantic rainforest. In addition, Atlantic rainforest scorpions presented a lower resistance to desiccation, exhibiting a higher mortality rate than the Caatinga dry forest individuals. These results suggest that T. pusillus can exhibit, via phenotypic plasticity or local adaptation, a broad range of tolerances that allow it to persist in different habitats. Furthermore, our findings suggest that T. pusillus individuals from the Caatinga dry forest have physiological attributes that allow them to resist prolonged desiccation, which may be related to adaptations that are intrinsic to the population from the dry forest. [ABSTRACT FROM AUTHOR]

Citrus plants face various abiotic stresses like drought during their life span which significantly affect their active growth and development. Tetraploid (4×) plants are more adaptable to environmental constraints than diploid (2×) plants by inducing critical physiological and biochemical processes. In this study, tetraploid and their corresponding diploid sour orange rootstocks were subjected to drought stress for 12 days. Results revealed that drought stress significantly affected plant physiology by reducing photosynthesis rate, stomatal conductance, transpiration rate, and leaf colour, which was prominent in diploid plants compared to tetraploid plants. In diploid plants, phenotypic differences (i.e. wilting and rolling of leaves) were also significant. Diploids with more accumulation of malondialdehyde and hydrogen peroxide in their leaves and roots exhibited more oxidative damage. It was observed that tetraploid plants had higher activities of peroxidase and catalase enzymes, while lower superoxide dismutase was recorded in the leaves and roots of plants. Higher glycine betaine, proline, total soluble protein, total phenolic content, and antioxidant activities were also observed in the leaves and roots of tetraploids. Overall, results suggest that tetraploids in citrus can have better defence mechanisms that help them to sustain under water deficit scenarios. [ABSTRACT FROM AUTHOR]

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As an important hormone response gene, Gretchen Hagen 3 (GH3) maintains hormonal homeostasis by conjugating excess auxin with amino acids during plant stress-related signaling pathways. GH3 genes have been characterized in many plant species, but they are rarely reported in potato. Here, 19 StGH3 genes were isolated and characterized. Phylogenetic analysis indicated that StGH3s were divided into two categories (group I and group III). Analyses of gene structure and motif composition showed that the members of a specific StGH3 subfamily are relatively conserved. Collinearity analysis of StGH3 genes in potato and other plants laid a foundation for further exploring the evolutionary characteristics of the StGH3 genes. Promoter analysis showed that most StGH3 promoters contained hormone and abiotic stress response elements. Multiple transcriptome studies indicated that some StGH3 genes were responsive to ABA, water deficits, and salt treatments. Moreover, qRT-PCR analysis indicated that StGH3 genes could be induced by phytohormones (ABA, SA, and MeJA) and abiotic stresses (water deficit, high salt, and low temperature), although with different patterns. Furthermore, transgenic tobacco with transient overexpression of the StGH3.3 gene showed positive regulation in response to water deficits by increasing proline accumulation and reducing the leaf water loss rate. These results suggested that StGH3 genes may be involved in the response to abiotic stress through hormonal signal pathways. Overall, this study provides useful insights into the evolution and function of StGH3s and lays a foundation for further study on the molecular mechanisms of StGH3s in the regulation of potato drought resistance. [ABSTRACT FROM AUTHOR]

Water is an essential component of life in the world. In addition to being crucial to keeping plants alive, water is also used in various areas, such as landscape irrigation, decorative pools, and ponds. The use of water more efficiently is getting more and more important day by day because of the increasing demands of different sectors. In cities with limited water resources, such as Konya, water should be used even more efficiently to reduce irrigation water quantities and prevent water losses. The potential use of the sub-surface drip irrigation method in the irrigation of green areas in Selçuklu district of Konya province was investigated, and the sub-surface drip irrigation method was compared with the fixed sprinkler irrigation method (pop-up) in terms of irrigation parameters (amount of irrigation water applied, plant water consumption) and plant characteristics (germination, plant height, number of mows, mowing weight, root depth). In the present experiments, 18 different sub-surface drip irrigation treatments (100, 80, and 60% irrigations + 40, 60, and 80 cm lateral spacings + 10 and 15 cm lateral depths) and three different sprinkler irrigation treatments (100, 80, and 60% irrigations) were used. Present findings revealed that sub-surface drip irrigation systems were suitable for irrigation of green areas, and this system was more advantageous for municipalities in terms of water savings, irrigation labor, and maintenance. For sub-surface drip irrigation systems, S1 (supply 100% of evaporation from Class-A pan + 40 cm lateral spacing + 10 cm lateral depth) treatments were found to be the best system arrangement for landscape irrigations in Selçuklu district in Konya province. [ABSTRACT FROM AUTHOR]

Climate change is increasing the frequency of extreme events such as droughts, limiting plant growth and productivity. Exogenous application of plant growth regulators, such as 24‐epibrassinolide (EBR), might be a solution as this molecule is organic, eco‐friendly, and biodegradable. This is the first research to examine possible roles of EBR on the hydraulic safety margin, physiological behaviour, and metabolism in Carapa guianensis Aubl. (Meliaceae) exposed to drought. C. guianensis is a widely distributed tree in tropical forests of the Amazon.The objective was to determine whether EBR can improve tolerance to water deficit in young C. guianensis by measuring hydraulic traits, nutritional, biochemical and physiological responses, and biomass. The experiment had four randomized treatments: two water conditions (control and water deficit) and two concentrations of EBR (0 and 100 nM EBR).EBR increased the water potential and hydraulic safety margin, increased CO2 fixation, and improved stomatal performance. EBR also stimulated antioxidant defences (SOD, CAT, APX, and POX).Overall, tretreatment with EBR improved drought tolerance of young C. guianensis plants. [ABSTRACT FROM AUTHOR]

• Water deficit exposed plants exhibited higher level of oxidative marker production. • Salicylic acid application help to revive stressed plants through triggered the antioxidative mechanism. • Salicylic acid influenced the Bacoside-A amount with integration of water deficit. Salicylic acid (SA), an eminent stress tolerance phytohormone, assists plants in dealing with abiotic stress. A pot experiment was carried out to substantiate the SA's ability to protect the medicinal herb Bacopa monnieri (L.) from exposure to water deficit. Diverse concentrations of SA (50, 75, 100, and 125 mg/l) were applied to plants as a foliar spray along with varied water levels based on reduced irrigation, WD1 (twice a week), and WD2 (once a week) against WW (once a day), with the first spray being applied after one week of water deficit treatment and the second one month later. The pool data for 2021 and 2022 demonstrated the resilience propensity of SA against water deficit in terms of oxidative markers detoxification (H 2 O 2 and MDA) via evoking the antioxidative mechanism of plants. The activity of antioxidants (SOD, CAT, GPOX, and APOX) and amount of non-enzymatic antioxidants (ascorbic acid, total phenolics and, flavonoid) including osmolytes (proline and total soluble sugar) was upsurged after SA (75 mg/l conc.) administration under both stressed and non-stressed plants. Additionally, stressed plants also revealed a recovery in their relative water content with intensifying the membrane stability index. Besides that positive repercussion in terms of medicinally bioactive compound (bacoside-A) content was also achieved with 75 mg/l conc. of SA foliar spray in addition to WD2. Conclusively, the present investigation unraveled the attainment of SA to ameliorate the B. monnieri (L.) under water deficit stress at moderate doses (up to 100 mg/l) by boosting their deterrence mechanisms through counterbalance of the physio-biochemical attributes. [ABSTRACT FROM AUTHOR]

• Genetic control over the root traits will help breeders improve the selection strategies. • The use of root traits can be a useful method for improving grain yield. • Selection of root traits linked to better plant growth under water-deficit conditions. • Identifying generations of maize with a vigorous root system which has better adaptation to deficit irrigation. Evaluation of various root traits and determination of their genetic control in response to water deficit stress is crucial for improving and stabilizing grain yield worldwide. The present study aimed at evaluating the gene action, heritability and genetic variances of grain yield and root morphological traits under water deficit conditions in mature maize. Seeds of seven maize genotypes, including B73 (maternal inbred line), MO17 (paternal inbred line), F 1 (SC704), F 2 , BC 1 , BC 2 and F 3 were sown in PVC tubes and grown under field water capacity. The maize plants were then subjected to three water regimes of 100% FC, 55% and 75% available water depletion at 5–6 leaf stage and continued to silk emergence in 2018 and 2019 (two years). The generation mean analysis results revealed that non-additive effects were greater than the additive effects. A high narrow sense heritability and additive variance were found for root dry weight and seminal root number, suggesting that selection in the parents' inbred lines or early segregating generations could be an efficient method for genetic improvement of the traits under deficit irrigation conditions. Contrarily, selection for grain yield, root volume, primary root length, root surface area, root diameter and root fresh weight should be delayed for several generations until a high level of gene fixation is attained. Based on correlation analysis and percent change of the studied traits under deficit irrigation conditions, SC704 and MO17 could be used as a source for water deficit tolerance in maize breeding programs. Overall, the results suggested that the selection of root traits linked to better plant growth has great potential to alleviate water deficit stress, contributing to sustainable maize production in drought-prone areas. [ABSTRACT FROM AUTHOR]

Drought severely limits sugarcane productivity in many regions of the world. This study characterized physiological responses to different drought durations in a diverse set of sugarcane genotypes in two crop cycles (plant and ratoon cane). A split-plot design was used where three drought treatments, namely, no drought (SD0), short-term drought (SD1), and long-term drought (SD2), were assigned to main plots and six diverse sugarcane genotypes to subplots. Drought reduced photosynthesis, leaf area index, and biomass yield. However, the study found significant differences in physiological responses to drought among genotypes in both crops. F03-362 (F1), KK09-0358 (BC1), and KK3 (cultivar) demonstrated greater tolerance to drought by maintaining comparatively higher photosynthetic activity, while KK09-0939 (BC2) and TPJ04-768 (BC1) were more sensitive. KK3 and UT12 (cultivar) consistently maintained comparatively higher levels of photosynthesis under drought in the ratoon crop, although stomatal conductance values were comparable to those of other genotypes. Drought significantly reduced dry matter in all genotypes, but more so in the two cultivars. The study demonstrated variable levels of sensitivity to drought among diverse genotypes with different physiological responses being induced by different drought treatments. This information is useful for sugarcane production management and breeding programs. [ABSTRACT FROM AUTHOR]

Winter rapeseed (Brassica rapa L.) can well‐adapt to environmental conditions such as barrenness, water deficit and low temperature in arid and semi‐arid planting regions and is the preferred rapeseed type. In this study, we analysed changes of root system morphology, antioxidant enzyme activity, endogenous hormone contents and differentially expressed proteins (DEPs) under control (CK), slight water deficit (SWD, 50–55% of maximum field water capacity), moderate water deficit (MWD, 40–45% of maximum field water capacity) and high water deficit (HWD, 30–35% of maximum field water capacity) conditions. Winter rapeseed experienced taproot elongation, decreased taproot diameter and increased lateral root number, under water deficit stress. The accumulation of reactive oxygen species (ROS) can cause membrane system peroxidation, and antioxidant enzyme activity increases to remove ROS. Changes in jasmonic acid (JA), salicylic acid (SA), cytokinin (CTK), auxin (IAA) and gibberellin (GA) levels promote the absorption of water and minerals by driving changes in the root system architecture to resist water deficit stress. A proteomic analysis has shown that DEPs are involved in energy metabolism, antioxidation response, osmotic regulation, hormone signal transduction, protein metabolism and the stress response, and these proteins are located in the peroxisome, chloroplast, mitochondrion, cell wall, vacuole, cytoplasm, extracellular space and cell membrane. In this study, multiple DEPs (malate dehydrogenase cytoplasmic 1 OS, 14‐3‐3‐like protein GF14 Psi, GA 3‐beta‐dioxygenase, glutathione reductase and jasmonate‐inducible protein) were involved in the root system architecture, revealing the complexity of the root response to water deficit. Significant/extremely significant synergistic relationships were observed between antioxidant enzyme activity and endogenous hormone contents. In conclusion, ROS, endogenous hormones and stress‐related proteins work synergistically to control the root system architecture of winter rapeseed roots in response to water deficit stress. [ABSTRACT FROM AUTHOR]

The article deals with the problems of sharing water, water resources management, protection of water resources in transboundary river basins. Discussed are the contradictions of the Central Asian countries in their approaches to solving water problems, depending on the geographical features of their location and the geopolitical situation in the region. On the example of the transboundary river Syrdarya, an analysis of the signed intergovernmental agreements and the mechanism of water allocation, an analysis of the fulfillment of interstate obligations on water allocation was carried out. It is shown that for the period from 1992 to 2019 the actual inflow into the territory of Kazakhstan along the Syrdarya river has always been above the established limit in annual terms, however, during the growing season, when water is needed for irrigation of crops, the share of water inflow was only a third of the annual volume, which does not meet the criterion of fair water allocation. Water supply through interstate canal over the same period was consistently below the agreed limit, i.e. water distribution provisions are not respected. At the same time, the incoming runoff has a high degree of mineralization, because in the middle reaches, on the territory of Uzbekistan, large volumes of collector-drainage waters are discharged into the channel of the Syrdarya River. Some recommendations are given for solving the problems of the water and energy complex that have developed in the region. [ABSTRACT FROM AUTHOR]

Foliar application of Atonik (sodium nitrophenolate) at crop critical growth stages is expected to improve crop physiology, morphology, and productivity. The present field study was conducted at the University of Agriculture, Faisalabad in autumn season of 2018 and 2019. Water deficit conditions were imposed by skip irrigation method. Plants were treated with foliar application of Atonik 10 (mg L−1) to evaluate the physiological, morphological, yield, and yield causative attributes of maize grown under deficit irrigation treatments. Randomized complete block design (RCBD) with split plots arrangement was used to layout the experiment having three replications. It was revealed that application of Atonik improved the crop's physiological attributes: relative leaf water contents (RLWC by 10%), chlorophyll contents (14%), and carotenoids content (15%) under water deficit conditions. Similarly, Atonik application augmented the leaf length at maturity, the number of green leaves at harvesting, and the number of grains row−1 of maize by 7%, 20% and 12%, respectively. Moreover, the application of Atonik amended the 100-grains weight, grain yield, and biological yield by 8%, 9% and 20%, respectively. In crux, application of Atonik is an excellent strategy to alleviate the detrimental influence of water deficit on physiological, morphological, and yield causative attributes of maize. [ABSTRACT FROM AUTHOR]

A field trial was carried out on maize (Zea mays L.) single cross (Pioneer 3080) variety in the Experimental Farm, Faculty of Agriculture, Omar Al-Mukhtar University, Al-Bayda, Libya during 2023 summer season to evaluate the effect of foliar application of five nano)silicon particles (NSP) concentrations, i.e., 1.5, 3, 4, 6 and 9 mg/ l besides the control treatment on maize growth, yield, yield attributes and chemical components of grains under three irrigation intervals (10, 17 and 24 days between irrigations) at the beginning of the second irrigation till harvest. Randomized complete block design in split plot arrangement was used in three replications, where irrigation intervals were randomly assigned to main plots and (NSP) concentrations were randomly distributed in sub-plots. Obtained results demonstrated that increasing interval between irrigations up to 24 days significantly decreased all the studied traits, except shelling percent and harvest index. Conversely, all the studied characters increased with increasing (NSP) concentrations, where (NSP) applications with 6 or 9 mg/ l produced the highest LAI (4.45 and 4.42) tallest plants (218.33 and 221.90 cm), highest shelling percent (80.73 and 81.83 %), high harvest index (41.57 and 43.32 %) and grain nitrogen content (1.52 and 1.60 %), respectively. However, spraying maize plants with 9 mg/ l (NSP) in resulted the heaviest ears (409.63 g), heaviest grain weight/ ear (335.25 g), 100-kernel weight (37.94 g), maximum grain and biological yields (9.09 and 20.98 t/ ha), respectively. On the other hand, irrigation intervals  (NSP) concentrations interaction had significant effects on all studied traits, where spraying maize plants with 6 or 9 mg/ l, generally alleviate the bad effects of increasing irrigation intervals up to 24 days. [ABSTRACT FROM AUTHOR]

Primary risk to rice (Oryza sativa L.) production is salinity intrusion and water scarcity, leading to a shortage of irrigation water and yield reduction. We examine the impact's effects of alternate wetting and drying (AWD) vs. continuous flooding (CF) and microbe application on yields of three rice cultivars (Ciherang, Inpari 34 Salin Agritan, Inpari 35 Salin Agritan) grown under slight and moderate soil salinity in the dry season (DS) 2017 and 2018. Under slight soil salinity, AWD and CF had nonsignificant difference in grain yield. Under a moderate soil salinity level, there was a substantial decrease in grain yield (8.2%), number of productive tillers, seeds panicle-1, and weight of 1000 grains with the plants grown under AWD. Increased soil salinity levels resulted in lower yield reduction with microbial than without microbial treatments. 'Ciherang' showed superiority over 'Inpari 34' and 'Inpari 35' under AWD at slight soil salinity. However, the yield reduction in the moderate salinity level was more remarkable for 'Ciherang' (18.1%) than 'Inpari 34' and 'Inpari 35' (9.7%) as salinity-tolerant varieties. The AWD used almost one-third less irrigation supplement than CF. This greatly assists small farmers in reducing the additional cost of pumping water. On average, AWD improved total water productivity by 32.7% under slight and 20.4% under moderate soil salinity over CF. Here, we lay out the potential for small farmers in slight salinity lowlands areas of the northern coast of Java to apply AWD during the DS. Farmers could manage water efficiently to prevent further yield loss and improve farm profitably. [ABSTRACT FROM AUTHOR]

Growing media and irrigation water levels are the most important factors affecting plant yield and quality throughout the world. The present research was conducted in a greenhouse located in the Batı Akdeniz Agricultural Research Institute between the 2019 and 2020 growing season. The study aims to determine the effects of different substrates and irrigation levels on yield and phenolic and essential oil compounds of ginger (Zingiber officinale) irrigated by means of a drip irrigation system. In order to investigate the effects of different substrates and irrigation levels on the physiological characteristics and yield of ginger, an experiment was conducted as factorial, in which the main factor was three substrates (S1: 75% cocopeat + 25% perlite, S2: 50% peat + 50% perlite, and S3: 25% zeolite + 75% peat) and the sub factor was four irrigation levels (I1:100% I2: 75%, I3: 50%, and I4:25%) were applied experimental plots according to the daily solar radiation values reaching the greenhouse, with 3 replications. The evapotranspiration values ranged between 49.7-198.7 L plant-1 and 51.7-206.9 L plant-1 in the 2019 and 2020 years, respectively. Rhizome fresh weight values for I1, I2, I3 and I4 were determined as 134.8, 94.7, 71.2 and 31.1 g in 2019 and 164.5, 148.1, 95.1 and 74.9 g in 2020, respectively. Water deficit stress significantly (P=0.01) increased the 6-gingerol, 6-shogaol, α-zingiberene, α-farnesene, and geranly-acetate contents while it decreased the β-sesquiphellandrene and ß-bisabolene content. It was found that the essential oil yield of ginger decreased depending on the increasing irrigation water stress levels. [ABSTRACT FROM AUTHOR]

Rice is more vulnerable to drought than maize, wheat, and sorghum because its water requirements remain high throughout the rice life cycle. The effects of drought vary depending on the timing, intensity, and duration of the events, as well as on the rice genotype and developmental stage. It can affect all levels of organization, from genes to the cells, tissues, and/or organs. In this study, a moderate water deficit was applied to two contrasting rice genotypes, IAC 25 and CIRAD 409, during their reproductive stage. Multi‐level transcriptomic, metabolomic, physiological, and morphological analyses were performed to investigate the complex traits involved in their response to drought. Weighted gene network correlation analysis was used to identify the specific molecular mechanisms regulated by each genotype, and the correlations between gene networks and phenotypic traits. A holistic analysis of all the data provided a deeper understanding of the specific mechanisms regulated by each genotype, and enabled the identification of gene markers. Under non‐limiting water conditions, CIRAD 409 had a denser shoot, but shoot growth was slower despite better photosynthetic performance. Under water deficit, CIRAD 409 was weakly affected regardless of the plant level analyzed. In contrast, IAC 25 had reduced growth and reproductive development. It regulated transcriptomic and metabolic activities at a high level, and activated a complex gene regulatory network involved in growth‐limiting processes. By comparing two contrasting genotypes, the present study identified the regulation of some fundamental processes and gene markers, that drive rice development, and influence its response to water deficit, in particular, the importance of the biosynthetic and regulatory pathways for cell wall metabolism. These key processes determine the biological and mechanical properties of the cell wall and thus influence plant development, organ expansion, and turgor maintenance under water deficit. Our results also question the genericity of the antagonism between morphogenesis and organogenesis observed in the two genotypes. [ABSTRACT FROM AUTHOR]

The biochemical response and gene expression in different grapevine cultivars to water deficit are still not well understood. In this study, we investigated the performance of four traditional Croatian Vitis vinifera L. cultivars ('Plavac mali crni', 'Istrian Malvasia', 'Graševina', and 'Tribidrag'), and one wild (Vitis vinifera subsp. sylvestris) genotype exposed to water deficit (WD) for nine days under semi-controlled conditions in the greenhouse. Sampling for biochemical and gene expression analyses was performed at days six and nine from the beginning of WD treatment. The WD affected the accumulation of metabolites with a significant increase in abscisic acid (ABA), salicylic acid (SA), and proline in the leaves of the stressed genotypes when the WD continued for nine days. Lipid peroxidation (MDA) was not significantly different from that of the control plants after six days of WD, whereas it was significantly lower (297.40 nmol/g dw) in the stressed plants after nine days. The cultivar 'Istrian Malvasia' responded rapidly to the WD and showed the highest and earliest increase in ABA levels (1.16 ng mg−1 dw, i.e., 3.4-fold increase compared to control). 'Graševina' differed significantly from the other genotypes in SA content at both time points analyzed (six and nine days, 47.26 and 49.63 ng mg−1 dw, respectively). Proline level increased significantly under WD (up to 5-fold at day nine), and proline variation was not genotype driven. The expression of aquaporin genes (TIP2;1 and PIP2;1) was down-regulated in all genotypes, coinciding with the accumulation of ABA. The gene NCED1 (9-cis-epoxycarotenoid dioxygenase) related to ABA was up-regulated in all genotypes under stress conditions and served as a reliable marker of drought stress. This work suggests that the stress response in metabolite synthesis and accumulation is complex, treatment- and genotype-dependent. [ABSTRACT FROM AUTHOR]

Background and Objective: As the country is faced with an acute shortage of edible oil and the deficient agricultural water caused by water shortage is the most limiting factor of crop production and productivity, this study was carried out to recognize and evaluate the related traits to growth and yield as well as the adaptation of sunflower specially to water deficit conditions. Materials and Methods: This experiment was carried out using a split-plot arrangement in a randomized complete block design with three replications. The main plots consisted of three deficit irrigation treatments: control, mild and severe deficit irrigation-based on the discharge of 50, 70 and 90 % of available moisture, respectively. The sub-plots consisted of six sunflower cultivars: Oscar, Felix, Shakira, Savana, Labad and Monaliza. The study site was located at the research farm of Safiabad (Dezful) Agricultural Research Center, Iran. Results: The results indicated that deficit irrigation led to a significant difference in oil percentage, biological yield, and yield and yield components of sunflower cultivars. Severe deficit irrigation was caused a significant reduction in stem height, stem diameter, head diameter and biological yield by 19.03%, 26.97% 24.34% and 45.08%, respectively, compared to the control. Moreover, grain number per head, grain weight per head and grain yield significantly decreased under severe water-deficit stress by 45.69%, 49.94% and 50%, respectively, compared to the control. In addition, the oil yield of all cultivars significantly decreased under severe deficit irrigation by 26.67% compared to the control. For the control, Oscar cultivar had the highest grain yield (5.34 t.ha-1). In contrast, Shakira cultivar had the lowest grain yield under severe deficit irrigation (2.67 t.ha-1). Under severe deficit irrigation, Labad cultivar had the highest grain yield (4.28 t.ha-1) compared with other cultivars. Conclusion: Totally, Felix and Labad cultivars are recommended for cultivation in Dezful region due to their greater stability in grain yield under deficit irrigation conditions. [ABSTRACT FROM AUTHOR]

An overview of publications on the hydrological consequences of climate change in the context of the ongoing and projected threats to water security is presented. Two hydrological indicators of water security are considered both at the global and regional scales: mean river flow regime as an indicator of the provision of the territory with surface water resources, as well as the flood regime, as an indicator of flood hazard. The paper is structured as follows. The first section briefly discusses the current understanding of the mechanisms of the influence of anthropogenic climate change on water resources and flood hazard. The second section considers the methodological aspects of constructing assessments of the ongoing changes in the river regimes, and reviews some of the estimates of changes in water resources and high river flow in the world and Russia. The third section is devoted to the global and regional assessments of future changes in the river runoff regime in the twenty-first century and discusses the methodological challenges of carrying out such assessments. The fourth section evaluates socio-economic consequences of the current and forecasted hydrological changes and their influence on water security. The paper is finalized by several summarizing remarks. [ABSTRACT FROM AUTHOR]

Background: Activity of plant aquaporins (AQPs) is extremely sensitive to environmental variables such as temperature, drought, atmospheric vapor pressure deficit, cell water status and also appears to be closely associated with the expression of plant tolerance to various stresses. The spatial and temporal expression patterns of genes of Tonoplast Intrinsic Proteins (TIPs) in various crops indicate the complex and diverse regulation of these proteins and are important in understanding their key role in plant growth, development and stress responses. Methods and results: Based on phylogenetic analysis, six distinct HaTIPs were selected for studying their spatial and temporal expression in sunflower (Helianthus annuus). In this study semi quantitative polymerase chain reaction (semi q-PCR) and real time polymerase chain reaction (q-PCR) analysis were used to study the spatial and temporal expression of HaTIPs in sunflower. The results indicated that all of HaTIPs showed differential expression specific to both the tissues and the accessions. Moreover, the expression of all HaTIPs was higher in cross compared to the parents. Results of semi q-PCR and real time PCR indicated an upregulation of expression of HaTIP-RB7 and HaTIP7 in drought tolerant entries at 12 h of 20% polyethylene glycol (PEG) treatment compared to 0 h. Conclusion: Hence these genes can be utilized as potential target in improving water use efficiency and for further genetic manipulation for the development of drought tolerant sunflower. This study may further contribute to our better understanding regarding the precise role of HaTIPs through their spatial and temporal expression analysis and their application in sunflower drought stress responses. [ABSTRACT FROM AUTHOR]

Climate change and rising temperatures caused water deficits due to lesser and irregular rainfalls, leading to lower production of crops. Morpho-physiological and yield contributing traits of Upland (G. hirsutim L.) cotton varieties grown under optimal water supply (control) and water deficit (experimental) conditions are presented in the article, total chlorophyll, chlorophyll "a", chlorophyll "b", carotenoids, the amounts of proline, malonyldialdehyde, yield per plant, cotton weight per boll, the number of seeds per boll and the number of bolls per plant and the results of their correlation analysis are presented. Under water deficit conditions, there is a strong positive correlation between the carotenoids in plant leaves and the number of bolls per plant, a strong negative correlation between the number of carotenoids and malonyldialdehyde, a strong negative correlation between malonyldialdehyde in plant leaves and the number of bolls per plant, a strong positive correlation between plant productivity and the number of bolls per plant was found to exist. It has been determined that the varieties of Ishonch and Navbahor-2 are more resistant to water deficit than C-6524 and Tashkent-6 in traits of physiological-biochemical and yield attributes. [ABSTRACT FROM AUTHOR]

Key message: PITOTAL, PIABS, DI0/RC, and δR0 are good markers of water stress in mango trees, demonstrating that consecutive drought cycles can develop differential acclimatization, depending on the rootstock used. Drought stress is one of the premier limitations to global agricultural production due to the complexity of the water-limiting environment and changing climate. In addition to indicating plant drought stress, photosynthetic performance is also determined by the scion/rootstock combination. The chlorophyll a fluorescence analysis is a reliable method to identify the most promising rootstock in the production of 'Uba' mango seedlings. We tested the hypothesis that different rootstocks can change the physiological responses related to chlorophyll a fluorescence, gas exchange, and proline content of different combinations of mango scion/rootstocks after three consecutive drought cycles, identifying the most vigorous rootstock with the ability to generate 'Uba' mango trees with greater differential resistance to drought. The Oleo rootstock (UC2/Oleo combination) has the greatest ability to imprint differential drought resistance in 'Uba' mango scions, generating plants with more vigor and better resistance to water deficit. The results suggest that the plant's consecutive cycles of drought have been "learned" as a resistance mechanism to cope with severe water shortages in the future. [ABSTRACT FROM AUTHOR]

DROUGHT is a significant abiotic stress that has a significant impact on rice growth, production, and quality. Furthermore, water scarcity is expected to become increasingly severe and frequent as a result of climate change, particularly in arid environments. Therefore, the objective of this study was to assess the impact of water deficit on morphological, physiological and agronomic of eight rice varieties with different genetic backgrounds. In addition to apply two PCR-based molecular marker systems ISSR and SCoT to assess the genetic diversity among the studied rice varieties. The results revealed that, water shortage stress significantly reduced relative water content, total chlorophyll content, grain yield, and yield characteristics. While, it significantly increased proline content and antioxidant enzyme activity (CAT, APX, and SOD) compared to normal irrigation treatment. The combined analysis of variance demonstrated that the mean squares for environments, varieties, and their interaction were highly significant for all investigated traits. The evaluated genotypes exhibited varied responses to drought-stress conditions. The Puebla and Hispagran varieties possessed the highest performance for most of the evaluated parameters and surpassed the other tested genotypes under water-deficit conditions. Therefore, it could be exploited in rice breeding programs for waterdeficit tolerance. The ISSR primers produce 46 amplified bands with an average of 6.6 bands/primer and 49.64% polymorphism. The SCoT primers reveal 46 bands with a mean of 11.5 bands/primer and 57% polymorphism. Both marker systems were informative, and the average polymorphism information content (PIC) was 0.33 and 0.38 for ISSR and SCoT, respectively. The dendrogram generated by ISSR and SCoT markers combined data divided the varieties into two major clusters. Cluster I consisted of the genotype Sakha 106. Cluster II retained seven varieties, which were further divided into two sub-clusters; Sakha 101, Sakha 105, Sakha 106, Sakha 107 constituted the first subgroup, while Giza 177, Hispagran, and Puebla formed the second one. It could be concluded that, Puebla, Hispagran, and sakha 108, which recorded the highest desirable values for the majority of studied traits under water deficit stress, could be used as a doner in rice breeding programs to develop new promising lines under water shortage conditions. [ABSTRACT FROM AUTHOR]

WATER deficit is a major environmental stress that has a tremendous effect on the physiological processes and productivity of rice. Thus, it is crucial to enhance rice tolerance to drought stress, especially under unpredictable climate changes and the increasing global population. This investigation aimed to study the impact of foliar-supplied nano-silica (Si-NPs) and potassium sulfate (K-sulphate) on some physiological, agronomic characters and crop water productivity of rice plants under water deficit and well-watered conditions during two summer seasons. The experimental design was a spilt-plot with four replications. The main plots were assigned to the two irrigation treatments; every 4 days (well-watered) and 12 days (water-deficit) after transplanting. The sub-plots were allocated by the three foliar treatments, namely, untreated control (distilled water application), foliar application of Si-NPs, and K-sulphate. The results displayed that the foliar applications, irrigation treatments, and their interactions had a significant influence on all the evaluated traits. Drought stress significantly reduced number of panicles per plant, number of grains per panicle, 1000-grain weight, and grain yield. However, water deficit considerably elevated antioxidant enzymes catalase (CAT) and peroxidase (POD) proline content compared to well-watered conditions. The foliar application of Si-NPs and K-sulphate was efficient in boosting drought tolerance by promoting antioxidant enzymes (CAT and POD) as well as proline accumulation compared with untreated plants. These positive influences were displayed in improving grain yield and its related traits as well as crop water productivity under drought stress conditions. Consequently, the utilization of foliar-applied Si-NPs and K-sulphate represents an applicable approach to enhance yield traits and crop water productivity of rice under water shortage conditions. [ABSTRACT FROM AUTHOR]

Cutleaf groundcherry (Physalis angulata L.) has the potential to be developed in various areas, including dryland. Information on drought-tolerant varieties, lines or genotypes is needed for the development of cutleaf groundcherry in dryland. Selecting drought-tolerant lines is an alternative for alleviating yield loss potency caused by water shortages. A pot experiment that aimed to investigate the response of cutleaf groundcherry lines to a different level of water deficit, expressed in field capacity (FC), was run in two factors of factorial randomized block design. Each line (PA-01, PA-03, PA-05, PA-08) was set up in water deficit treatment (100, 80, 60, 40, and 20% FC). The result showed that vegetative growth and fruit production, such as fruit number and weight, mainly decreased at 60 or 40 % FC. In contrast, TSS increased at a higher water deficit which was in line with total flavonoid content, even inconsistently. PA-03 and PA-08 experienced a reduction in fruit weight at 40% FC, whereas other lines occurred at 60% FC. Water use efficiency (WUE) increased under severe water stress. Compared to other lines, PA-03 and PA-08 exhibit higher WUE at 60% FC. In conclusion, PA-03 and PA-08 lines were tolerant of water deficit. [ABSTRACT FROM AUTHOR]

Water scarcity is a serious constraint for agriculture, and global warming and climate change can exacerbate it in many areas. Therefore, sustainable approaches must be implemented to deal with current and future water scarcity scenarios. Genetic and chemical approaches are being applied to manage this limitation and maintain crop yields. In particular, biostimulants obtained from natural sources such as marine algae are promising aids for coping with water deficit stress in agriculture. Here we present a bioprospection study of extracts of the macroalgae Bonnemaisonia hamifera, Galaxaura rugosa, Dasycladus vermicularis, Ulva clathrata, Cystoseira foeniculacea, Cystoseira humilis, Lobophora dagamae, Colpomenia sinuosa and Halopteris scoparia from the north coast of Tenerife, in the Canary Islands. The aqueous extracts of Bonnemaisonia hamifera, Galaxaura rugosa, Dasycladus vermicularis and Cystoseira humilis show biostimulant activity against water deficit stress in tomato seedlings under controlled conditions, providing higher tolerance than the mock-treated control. The Galaxaura rugosa extract showed the highest biostimulant activity against water deficit stress. We demonstrate that this positive effect involves the activation of the abscisic acid (ABA) pathway in Arabidopsis thaliana (arabidopsis) and Solanum lycopersicum (tomato). Application of G. rugosa extract to the root system by drenching tomato seedlings subjected to water deficit leads to improved CO2 assimilation and water use efficiency (WUEp), compared to mock-treated plants. These results highlight a new potential seaweed source of substances with osmoprotectant properties, useful for biostimulant development. Future studies may provide further insight into which components of the seaweed extract induce activation of the ABA pathway. [ABSTRACT FROM AUTHOR]

Introduction: Water is one of the important factors affecting the yield of leafy vegetables. Lettuce, as a widely planted vegetable, requires frequent irrigation due to its shallow taproot and high leaf evaporation rate. Therefore, screening drought-resistant genotypes is of great significance for lettuce production. Methods: In the present study, significant variations were observed among 13 morphological and physiological traits of 42 lettuce genotypes under normal irrigation and water-deficient conditions. Results: Frequency analysis showed that soluble protein (SP) was evenly distributed across six intervals. Principal component analysis (PCA) was conducted to transform the 13 indexes into four independent comprehensive indicators with a cumulative contribution ratio of 94.83%. The stepwise regression analysis showed that root surface area (RSA), root volume (RV), belowground dry weight (BDW), soluble sugar (SS), SP, and leaf relative water content (RWC) could be used to evaluate and predict the drought resistance of lettuce genotypes. Furthermore, the drought resistance ranks of the genotypes were similar according to the drought resistance comprehensive evaluation value (D value), comprehensive drought resistance coefficient (CDC), and weight drought resistance coefficient (WDC). The cluster analysis enabled the division of the 42 genotypes into five drought resistance groups; among them, variety Yidali151 was divided into group I as a strongly drought-resistant variety, group II included 6 drought-resistant genotypes, group III included 16 moderately drought-resistant genotypes, group IV included 12 droughtsensitive genotypes, and group V included 7 highly drought-sensitive genotypes. Moreover, a representative lettuce variety was selected from each of the five groups to verify its water resistance ability under water deficit conditions. In the drought-resistant variety, it was observed that stomatal density, superoxide anion ðO2:-wfi2Þ production rate, and malondialdehyde (MDA) content exhibited a low increase rate, while catalase (CAT), superoxide dismutase (SOD), and that peroxidase (POD) activity exhibited a higher increase than in the drought-sensitive variety. Discussion: In summary, the identified genotypes are important because their drought-resistant traits can be used in future drought-resistant lettuce breeding programs and water-efficient cultivation. [ABSTRACT FROM AUTHOR]

Medicinal plants accommodated by understory habitats can easily suffer over-exploitation in the heavy harvest of natural products. It is necessary to develop a sustainable cultural protocol to provide high-quality stocks for efficient regeneration. Drought places stress on medicinal plants during their culture by limiting new sprout growth and reducing the quality of medicinal extracts. Artificial mediating approaches should be considered in a sustainable regime of medicinal plant culture to test the potential tradeoff between resistance to drought and production ability. In this study, Rabdosia rubescens seedlings were raised in three light-emitting diode (LED) spectra from red (71.7% red, 14.6% green, 13.7% blue), green (26.2% red, 17.4% green, 56.4% blue), and blue (17.8% red, 33.7% green, 48.5% blue) lights. Mown seedlings were subjected to a simulated drought event. Drought stressed the seedlings by reducing the growth, dry mass, nitrogen (N) uptake, and oridonin content. Mowing increased the oridonin content but decreased total C and N accumulation and the δ13C level. The red light benefitted starch accumulation only under the well-watered condition, and the green light induced an upregulation of δ13C but decreased antioxidant activity. Oridonin content was negatively associated with combined δ13C and catalase activity. Overall, either mowing or blue light can be recommended for the culture of R. rubescens to increase oridonin content, alleviating some of the negative consequences of drought. [ABSTRACT FROM AUTHOR]

Water restriction is a critical environmental condition for plants capable of promoting severe losses in agricultural yield. Our hypothesis was that sulfur (S) supplementation alleviates drought damage for enhanced performance of cowpea cultivars under semiarid conditions. Two parallel experiments were conducted in greenhouse and field, using two cowpea cultivars (Xique-xique and Novaera) subjected to two water regimes (control and drought) and three S levels (S-40, S-80 and S-120 kg ha−1). Drought had a more restrictive impact on cowpea in greenhouse than in field. Drought-stressed plants in greenhouse showed drastic reductions in net photosynthesis, stomatal conductance and dry mass, for both cowpea cultivars as compared to controls. S-80 supplementation in greenhouse and S-120 in field promoted growth recovery of stressed-Novaera plants as related to S-40 stressed ones, exhibiting a performance closer to that of well-irrigated plants. Superior performance of S-supplemented stressed Novaera plants was associated with activation of mechanisms for water retention, likely osmotic adjustment, evidenced by increased water content, stomatal conductance and transpiration. These physiological adjustments allowed plants to maintain elevated net photosynthesis and growth under drought. In conclusion, S supplementation proves effective in mitigating drought damage in Novaera cultivar, offering potential for cultivating cowpea plants in water-scarce environments. [ABSTRACT FROM AUTHOR]

It is important to evaluate any effects that biochar may have on tomato yield under deficit-irrigation to develop water-saving and yield-increasing best management practices for greenhouse tomato production. For this purpose, greenhouse trials were conducted in 2021 and 2022 with five biochar (B) application rates and three irrigation (W) levels. The B treatments were B0: 0 t ha−1; B1: 15 t ha−1; B2: 30 t ha−1; B3: 45 t ha−1; and B4: 60 t ha−1, and the W levels were W1: 50–70% of field capacity (θf); W2: 60–80% of θf; and W3B0: 70–90% of θf full irrigation without biochar, which was designated as the control. Our objective was to quantify the effects of biochar on the characteristics of tomato sources and sinks to determine, first, the optimal irrigation–biochar combination to achieve high yield tomato production, and, second, evaluate the mechanisms of this effect. At W1 and W2 irrigation levels, the addition of 30–60 t ha−1 and 45–60 t ha−1 biochar could compensate for the adverse effects of deficit-irrigation on the tomato source and sink characteristics. Our results show that in both years the highest tomato yield was obtained with the W2 irrigation level and the B3 biochar application rate, with 52% higher tomato yield compared to the lowest value obtained with the W1 irrigation level and B0 application rate. We conclude that biochar application can improve tomato yield by promoting the filling rather than the building of the sink capacity. The tomato yield was mainly affected by the net photosynthetic rate (Pn), followed by the leaf area, and the leaf chlorophyll content indirectly affected tomato yield through Pn. The W2 irrigation level combined with the B3 biochar application rate resulted in the best water–biochar combination under the experimental conditions. [ABSTRACT FROM AUTHOR]

The steadfast propensity to global warming has had a severe impact on overall viticulture. Given the observed increase in growing season temperatures in Europe (+1.7 °C from 1950 to 2004), between 2000 and 2049, it is assumed that temperatures for major wine regions will increase on average by about +0.42 °C per decade and will generally increase by +2.04 °C. Phenolic compound development is affected by environmental parameters such as ultraviolet (UV) radiation, sunlight, maximum and minimum temperatures, and grapevine water status. Proanthocyanidins, flavan-3-ol monomers, and other pigmented polymers are impacted by soil management and canopy handling strategies, as well as obtaining a microclimate around the developing bunch. This review, after a necessary summary of the synthesis of phenolic compounds in the berry (flavonoids and non-flavonoids) to let the lector delve into the topic, describes the impact of climate change and therefore of environmental factors on their accumulation and storage throughout ripening and harvesting. For example, high berry temperatures can reduce the total concentrations of skin anthocyanin; a 35 °C temperature entirely obstructed anthocyanin synthesis, and instead quercetin 3-glucoside could be enhanced with exposure to solar radiation. In addition, increments via water deficit in the relative abundance of methoxylated anthocyanins were also found. The vineyard management strategies to mitigate the degradation of phenolic compounds and preserve their concentration are also further discussed. Finally, it is believed that it is necessary today to establish an elastic and variable approach towards the single wine year, moving away from the concept of product standardization. [ABSTRACT FROM AUTHOR]

Laboratory and field studies were performed to evaluate the role of potassium as seed priming agent in combination with foliar supply for induction of drought tolerance in green gram. In the laboratory experiment, best priming treatment of potassium (2%) was selected when green gram was exposed to PEG induced drought (-2.0 MPa). Field experiment was carried out to test the performance of screened priming treatment along with sequential supply of potassium under normal irrigation and drought at 40 days after sowing. Drought significantly affected different agronomic and yield traits including plant height, branches plant−1, number of pods plant−1, grains per pod−1, 1000 grains weight, grain yield and biological yield. Seed priming improved different agronomic and yield related traits as compared to non-primed seed except number of grains per pod. Peak values of CGR (11.39 g m−2 day−1) during 45-55 DAS, LAI (2.75) at 45 DAS, Final NAR (17.39 g m−2 day−1), final LAD (86.65 Days), LWR (0.59) at 35 DAS, LAR (283.27 cm2 g−1) at 35 DAS were recorded under drought with hydropriming of seed along with 1% K sequential spray as compared to rest of treatment. Maximum branches per plant (10.33), pods per plant (46.67), grain yield (750.38 kg ha−1), biological yield (1923.54 kg ha−1), relative water contents (75.26%), chlorophyll contents (44.75) and membrane stability index (83.95%) were recorded in with seed hydropriming + 1% K sequential spray. Thus, seed hydropriming along with 1% K sequential spray can be opted to alleviate drought in green gram under field condition. [ABSTRACT FROM AUTHOR]