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Simple Summary: Climate change poses a significant threat to agriculture, primarily through the increased frequency and severity of droughts. These extreme weather conditions reduce water availability, impacting crop yields and biomass production. Drought stress is particularly challenging for regions already prone to water scarcity, compromising food security. Addressing these issues requires innovative strategies and a thorough understanding of plant responses to water deficit conditions. This study aims to unravel the molecular mechanisms underlying drought tolerance in Citrus, crucial for developing adaptive strategies. The findings show that Bitters (C22) exhibits greater drought tolerance than Carrizo Citrange and identify key genes involved in responding to water scarcity. In conclusion, this research enhances our understanding of how citrus plants respond to water stress and identifies promising candidate genes. These insights will guide future research aimed at developing drought-tolerant plants. Agriculture faces the dual challenge of increasing food production and safeguarding the environment. Climate change exacerbates this challenge, reducing crop yield and biomass due to drought stress, especially in semi-arid regions where Citrus plants are cultivated. Understanding the molecular mechanisms underlying drought tolerance in Citrus is crucial for developing adaptive strategies. Plants of two citrus rootstocks, Carrizo Citrange and Bitters (C22), were grown in aerated half-strength Hoagland's nutrient solution. Post-acclimation, the plants were exposed to a solution containing 0% (control) or 15% PEG-8000 for 10 days. Leaf malonyl dialdehyde (MDA) and hydrogen peroxide (H2O2) content were measured to assess the reached oxidative stress level. Total RNA was extracted, sequenced, and de novo-assembled. Weighted Gene Correlation Network Analysis (WGCNA) was conducted to examine the relationship between gene expression patterns and the levels of MDA and H2O2 used as oxidative stress indicators. Plant visual inspection and MDA and H2O2 contents clearly indicate that Bitters is more tolerant than Carrizo towards PEG-induced drought stress. RNA-Seq analysis revealed a significantly higher number of differentially expressed genes (DEGs) in Carrizo (6092) than in Bitters (320), with most being associated with drought sensing, ROS scavenging, osmolyte biosynthesis, and cell wall metabolism. Moreover, the WGCNA identified transcription factors significantly correlated with MDA and H2O2 levels, thus providing insights into drought-coping strategies and offering candidate genes for enhancing citrus drought tolerance. [ABSTRACT FROM AUTHOR]

Dirigent (DIR) genes play a pivotal role in plant development and stress adaptation. Manihot esculenta Crantz, commonly known as cassava, is a drought-resistant plant thriving in tropical and subtropical areas. It is extensively utilized for starch production, bioethanol, and animal feed. However, a comprehensive analysis of the DIR family genes remains unexplored in cassava, a crucial cash and forage crop in tropical and subtropical regions. In this study, we characterize a total of 26 cassava DIRs (MeDIRs) within the cassava genome, revealing their uneven distribution across 13 of the 18 chromosomes. Phylogenetic analysis classified these genes into four subfamilies: DIR-a, DIR-b/d, DIR-c, and DIR-e. Comparative synteny analysis with cassava and seven other plant species (Arabidopsis (Arabidopsis thaliana), poplar (Populus trichocarpa), soybean (Glycine max), tomato (Solanum lycopersicum), rice (Oryza sativa), maize (Zea mays), and wheat (Triticum aestivum)) provided insights into their likely evolution. We also predict protein interaction networks and identify cis-acting elements, elucidating the functional differences in MeDIR genes. Notably, MeDIR genes exhibited specific expression patterns across different tissues and in response to various abiotic and biotic stressors, such as pathogenic bacteria, cadmium chloride (CdCl2), and atrazine. Further validation through quantitative real-time PCR (qRT-PCR) confirmed the response of DIR genes to osmotic and salt stress. These findings offer a comprehensive resource for understanding the characteristics and biological functions of MeDIR genes in cassava, enhancing our knowledge of plant stress adaptation mechanisms. [ABSTRACT FROM AUTHOR]

Drought stress significantly affects the growth, development, and yield of cotton, triggering the response of multiple genes. Among them, ascorbate peroxidase (APX) is one of the important antioxidant enzymes in the metabolism of reactive oxygen species in plants, and APX enhances the ability of plants to resist oxidation, thus increasing plant stress tolerance. Therefore, enhancing the activity of APX in cells is crucial to improving plant stress resistance. Previous studies have isolated differentially expressed proteins under drought stress (GhAPX7) in drought-resistant (KK1543) and drought-sensitive (XLZ26) plants. Thus, this study analyzed the expression patterns of GhAPX7 in different cotton tissues to verify the drought resistance function of GhAPX7 and explore its regulatory pathways. GhAPX7 had the highest expression in cotton leaves, which significantly increased under drought stress, suggesting that GhAPX7 is essential for improving antioxidant capacity and enzyme activities in cotton. GhAPX7 silencing indirectly affects pronounced leaf yellowing and wilting in drought-resistant and drought-sensitive plants under drought stress. Malondialdehyde (MDA) content was significantly increased and chlorophyll and proline content and APX enzyme activity were generally decreased in silenced plants compared to the control. This result indicates that GhAPX7 may improve drought resistance by influencing the contents of MDA, chlorophyll, proline, and APX enzyme activity through increased expression levels. Transcriptome analysis revealed that the drought-related differentially expressed genes between the control and treated groups enriched plant hormone signal transduction, MAPK signaling, and plant–pathogen interaction pathways. Therefore, the decreased expression of GhAPX7 significantly affects the expression levels of genes in these three pathways, reducing drought resistance in plants. This study provides insights into the molecular mechanisms of GhAPX7 and its role in drought resistance and lays a foundation for further research on the molecular mechanisms of response to drought stress in cotton. [ABSTRACT FROM AUTHOR]

Stomatal movement is critical for water transpiration, gas exchange, and responses to biotic stresses. Abscisic acid (ABA) induces stomatal closure to prevent water loss during drought. We report that Arabidopsis CIPK8 negatively regulates ABA‐mediated stomatal closure and drought tolerance. CIPK8 is highly enriched in guard cells and transcriptionally induced by ABA. Functional loss of CIPK8 results in hypersensitive stomatal closure to ABA and enhanced drought tolerance. Guard cell‐specific downregulation of CIPK8 mimics the phenotype of cipk8 whereas guard cell‐specific expression of a constitutive active CIPK8 (CIPK8CA) has an opposite effect, suggesting a cell autonomous activity of CIPK8. CIPK8 physically interacts with CBL1 and CBL9. Functional loss of CBL1 and CBL9 mimics ABA‐hypersensitive stomatal closure of cipk8 whereas abolishes the effect of CIPK8CA, indicating that CIPK8 and CBL1/CBL9 form a genetic module in ABA‐responsive stomatal movement. SlCIPK7, the functional homolog of CIPK8 in tomato (Solanum lycopersicum), plays a similar role in ABA‐responsive stomatal movement. Genomic editing of SlCIPK7 results in more drought‐tolerant tomato, making it a good candidate for germplasm improvement. Summary statement: ABA‐induced stomatal closure is an important response of plants when challenged by drought. This study reports that Arabidopsis CIPK8 and its homolog SlCIPK7 in tomato negatively mediate stomatal closure upon ABA. Knocking‐out either gene results in more drought‐tolerant plants, making it a good candidate for germplasm improvement. [ABSTRACT FROM AUTHOR]

Introduction: With the approach of attention to the environment, the use of natural materials can be effective in reducing the harmful effects of chemical fertilizers and artificial growth regulators. Drought stress is one of the main limitations of food production around the world, and due to increasing population and water deficiency, there is a global attention for using some materials to increase resistant of plant to drought stress. Chemical stimulants are currently used for decreasing negative effects of water stress in plant. Now a days, use of natural materials, such as plant extract is recommended by researchers. Garlic extract is one of the natural extracts that contains many enzymes and more than 200 biochemical compounds that, due to its richness in minerals and plant hormones, causes cell enlargement, cell division and, plant growth. Humic acid is created from the decomposition of organic matter and is beneficial to plant growth and development. Therefore, the aims of this research were to study the effects of using natural substances of humic acid and garlic extract on nutrients uptake (NPK) and growth of wheat plant under drought stress. Materials and methods: This study was performed during 2018 in a completely randomized design with factorial arrangement in three replications under greenhouse conditions. The studied soil with texture class of loam had pH = 8.11 and EC = 1.28 dS m-1. Experimental factors include drought stress at three levels of 95%, 65% and 45% of field capacity, garlic extract at three levels of foliar application of 0, 2% and 4% and humic acid at two levels of foliar application of 0 and 300 mg l-1. Drought stress were treated by the weight method, 17 days after sowing. Foliar application of humic acid (twice, 13 and 20 days after threating the drought stress) and garlic extract (three times, 18, 24 and 27 days after threating the drought stress) were performed by spraying 150 ml pot-1 of the solutions in each time. The plants were harvested 54 days after sowing and the parameters of shoot dry weight and uptake of nitrogen, phosphorus and potassium in plant were measured. Statistical analysis was done using SAS 9.4 software and the comparison of means was done using Tukey's test at the 5% probability level. [ABSTRACT FROM AUTHOR]

Drought presents a major risk to wheat growth and productivity under changing climates. During the last few years, various morphological and physiological approaches were used to overcome drought stress-associated problems. Cultivation of tolerant wheat cultivars can serve as a sustainable choice to raise wheat yield under water stress. Herein, field trials were carried out at the experimental farm of Ismailia Agricultural Research Station, Egypt, in two successive growing seasons (2020/2021 and 2021/2022) to investigate the response of four Egyptian bread wheat cultivars (Misr 1, Misr 3, Giza 171, and Sakha 95) to drought stress according to morpho-physiological characteristics, yield, and stress indices. Irrigation treatments and cultivars were assigned to the main and sub-plots, consequently, in a split-plot design with three replicates. The findings revealed that in both the first and second seasons, drought drastically revoked growth vigor of shoot, growth vigor of flag leaf, relative water content (%), membrane stability index (%), photosynthetic pigments, heading (days), maturity (days), as well as yield and yield attributes: spike length, number of spikes/m2, spike weight, grain number/spike, 100-kernel weight, grain yield/m2, straw yield/m2, biological yield/m2, and harvest index of all four wheat cultivars. Conversely, drought caused a marked increase in saturation water deficit (%), carotenoids content, and NKP uptake of all four wheat cultivars in both study seasons. The current study found that all four of the wheat cultivars were drought-tolerant plants. These cultivars exhibited similar drought-tolerant behaviors, which included decreased loss in relative water content, membrane stability, and photosynthetic pigment levels, consequently reducing wheat grain yield loss under water stress. Additionally, the drought tolerance indices of Sakha 95 > Giza 171 > Misr 1 > Misr 3 were revealed by the stress sensitivity index (SSI), mean productivity (MP), stress tolerance index (STI), and yield stability index (YSI). In conclusion, Misr 3 was the least tolerant wheat cultivar and Sakha 95 was the most tolerant. These results can be applied to breeding programs by plant breeders. [ABSTRACT FROM AUTHOR]

DESERT date or Balanites aegyptiaca (L.) Del is one of the most prevalent, wild plant species in the arid regions of Africa and the Middle East. The desert date tolerates a broad range of soil types and can be found in a variety of habitat types. It has a wide ecological distribution but is mainly found on level alluvial sites with deep sandy loam and free access to water. B.egyptiaca is used in African and Indian traditional medicine. Many underutilized tree species are good sources of food, fodder and possible therapeutic agents. B. aegyptiaca tree is considered drought tolerant and a potential source of many secondary metabolites. This study investigated the adaptive and physiological response to severe aridity and drought stress on the growth of B. aegyptiaca in El-Kharga Oasis, which is the driest region in the Western Desert. Clay soil was found to be dominant in the mechanical soil analysis. Weakly to moderately calcareous soil carbonate was found, and the estimated pH values of the soil solution appeared to be slightly alkaline and exhibited a comparatively high electric conductivity. Total free amino acid concentration was greater than that of soluble protein and sugar. Results indicated that B. aegyptiaca is a drought-tolerant plant in severely arid areas that are subject to drought stress. [ABSTRACT FROM AUTHOR]

Arid and semi‐arid areas are facing increasingly severe water deficits that are being intensified by global climate changes. Microbes associated with plants native to arid regions provide valuable benefits to plants, especially in water‐stressed environments. In this study, we used 16S rDNA metabarcoding analysis to examine the bacterial communities in the bulk soil, rhizosphere and root endosphere of the plant Malva sylvestris L. in Morocco, along a gradient of precipitation. We found that the rhizosphere of M. sylvestris did not show significant differences in beta‐diversity compared to bulk soil, although, it did display an increased degree of alpha‐diversity. The endosphere was largely dominated by the genus Rhizobium and displayed remarkable variation between plants, which could not be attributed to any of the variables observed in this study. Overall, the effects of precipitation level were relatively weak, which may be related to the intense drought in Morocco at the time of sampling. The dominance of Rhizobium in a non‐leguminous plant is particularly noteworthy and may permit the utilization of this bacterial taxon to augment drought tolerance; additionally, the absence of any notable selection of the rhizosphere of M. sylvestris suggests that it is not significatively affecting its soil environment. [ABSTRACT FROM AUTHOR]

In order to determine the physiological mechanism of drought resistance of northern wheat in China, six drought resistant wheat and one sensitivity to drought wheat were planted in pots. They were subjected to drought treatment and normal water when the plants grew to the 3-leaf stage. Samples were collected at 10, 20, 30, and 40 days after the drought treatment, respectively. The electrical conductivity, photosynthetic parameters, chlorophyll fluorescence parameters, sugar content, proline content, protein content, and active oxygen scavenging enzyme activity of the plants were detected, and the agronomic traits of the wheat varieties were investigated at maturity. The results indicated that the phenotype and yield-related factors of Darkhan 144 changed little under the drought stress. The relative electrical conductivity of Kefeng 6 and Darkhan 166 was lower under the drought stress, and their cell membrane was less damaged. The Darkhan 144 and Darkhan 166 had higher drought resistance coefficients, and were the wheat varieties with stronger drought resistance. However, the physiological mechanisms of drought resistance of these three wheat were different: Darkhan 144 maintained a higher photosynthetic activity under the drought stress; Darkhan 166 maintained a higher protein content, photosynthetic activity and active oxygen scavenging enzyme activity. In addition, other drought-resistant varieties Kefeng 6, Kefeng 10 and Longmai 26 had a higher content of osmoregulatory substances under the drought stress. [ABSTRACT FROM AUTHOR]

Simple Summary: This research article investigates the ploidy's impact on daylilies' (Hemerocallis spp.) response to water deficit conditions. By analyzing the morphological and physiological changes in diploid and tetraploid plants under drought stress, this study aims to elucidate the adaptive mechanisms that contribute to their differential tolerance levels. The results reveal distinct responses in the chlorophyll content, flavonoid accumulation, and nitrogen balance between the two ploidy groups, highlighting the superior stress resistance of tetraploid daylilies. The conclusions emphasize the importance of considering ploidy in understanding plant responses to drought stress and suggest the potential for cultivating drought-tolerant varieties to mitigate water scarcity challenges. This study's insights hold significant value for society by informing strategies for sustainable floriculture, enhancing greenery resilience to climate change, and promoting water-efficient plant breeding practices. This study aimed to understand the differences in the performance of diploid and tetraploid daylily cultivars under water deficit conditions, which are essential indicators of drought tolerance. This research revealed that tetraploid daylilies performed better than diploid varieties in arid conditions due to their enhanced adaptability and resilience to water deficit conditions. The analysis of the results highlighted the need to clarify the specific physiological and molecular mechanisms underlying the enhanced drought tolerance observed in tetraploid plants compared to diploids. This research offers valuable knowledge for improving crop resilience and sustainable floricultural practices in changing environmental conditions. The morphological and physiological parameters were analyzed in 19 diploid and 21 tetraploid daylily cultivars under controlled water deficit conditions, and three drought resistance groups were formed based on the clustering of these parameters. In a high drought resistance cluster, 93.3% tetraploid cultivars were exhibited. This study demonstrates the significance of ploidy in shaping plant responses to drought stress. It emphasizes the importance of studying plant responses to water deficit in landscape horticulture to develop drought-tolerant plants and ensure aspects of climate change. [ABSTRACT FROM AUTHOR]

This study used a descriptive-analytical method to assess how vulnerable farmers in Fars Province's rural regions near the Tashk and Bakhtegan lakes are to the effects of climate change. For this purpose, 17 villages around Tashk and Bakhtegan lakes with 2511 households, who are engaged in agricultural activities, were investigated. To achieve the research goals, a broad range of indexes were determined with the dimensions of exposure, sensitivity, and adaptive capacity to climate change according to the Climate Vulnerability Index (CVI) and were evaluated in the field studies. According to the results, 52.93% of communities were highly vulnerable to climate change. On the other hand, only 23.52% of farmers had very low vulnerability, and 23.52% had moderate vulnerability. The local farmers were aware of the climate change in the studied region with an average of 4.56. Given that more than half of the villagers are highly vulnerable to climate change, the government and relevant institutions need to increase their resilience to vulnerability. Increasing vulnerability requires careful measurement and monitoring of all related variables, increasing adaptation to the generalization of insurance, access to facilities, and reducing climatic sensitivities by increasing livelihood diversification, reducing unemployment, and using drought-resistant plants. [ABSTRACT FROM AUTHOR]

Drought strongly limits tomato yield, and the introgression of genes from wild tomatoes is a powerful tool to obtain drought‐tolerant progenies. The aim of this study was to select drought‐tolerant transgressive progeny obtained from interspecific crosses between drought‐susceptible tomatoes (Solanum lycopersicum) × drought‐tolerant wild species (Solanum pennellii) under in vitro and greenhouse conditions. BC1F2 populations were advanced from backcrosses between F1 × Jumbo AG‐592 (cultivar for fresh consumption) and F1 × BRS Tospodoro (cultivar for industrial processing). For this, BC1F2 seeds were germinated in vitro and evaluated for tolerance to drought. Then, eight genotypes from each BC1F2 were selected and submitted to 14 days of drought (0% of water supply) or well‐watered (100% of water supply) in greenhouse conditions and evaluated for growth, water balance and gas exchanges. Using in vitro assays with mannitol‐induced drought proved to be effective for the initial screening of drought‐tolerant BC1F2 plants, while greenhouse experiments showed that drought decreased photosynthesis in all genotypes, but almost all the BC1F2 progenies had greater photosynthetic capacity, water balance and growth than their commercial parents. As a result, we selected six progenies for fresh consumption and six progenies for industrial processing with increased drought tolerance. [ABSTRACT FROM AUTHOR]

SUMMARY: Developing climate‐resilient crops is critical for future food security and sustainable agriculture under current climate scenarios. Of specific importance are drought and soil salinity. Tolerance traits to these stresses are highly complex, and the progress in improving crop tolerance is too slow to cope with the growing demand in food production unless a major paradigm shift in crop breeding occurs. In this work, we combined bioinformatics and physiological approaches to compare some of the key traits that may differentiate between xerophytes (naturally drought‐tolerant plants) and mesophytes (to which the majority of the crops belong). We show that both xerophytes and salt‐tolerant mesophytes have a much larger number of copies in key gene families conferring some of the key traits related to plant osmotic adjustment, abscisic acid (ABA) sensing and signalling, and stomata development. We show that drought and salt‐tolerant species have (i) higher reliance on Na for osmotic adjustment via more diversified and efficient operation of Na+/H+ tonoplast exchangers (NHXs) and vacuolar H+‐ pyrophosphatase (VPPases); (ii) fewer and faster stomata; (iii) intrinsically lower ABA content; (iv) altered structure of pyrabactin resistance/pyrabactin resistance‐like (PYR/PYL) ABA receptors; and (v) higher number of gene copies for protein phosphatase 2C (PP2C) and sucrose non‐fermenting 1 (SNF1)‐related protein kinase 2/open stomata 1 (SnRK2/OST1) ABA signalling components. We also show that the past trends in crop breeding for Na+ exclusion to improve salinity stress tolerance are counterproductive and compromise their drought tolerance. Incorporating these genetic insights into breeding practices could pave the way for more drought‐tolerant and salt‐resistant crops, securing agricultural yields in an era of climate unpredictability. Significance Statement: This work compare some of the key traits that differentiate between xerophytes (naturally drought‐tolerant plants) and mesophytes (to which majority of the crops belong). Incorporating these genetic insights into breeding practices could pave the way for more drought‐tolerant and salt‐resistant crops, securing agricultural yields in an era of climate unpredictability. [ABSTRACT FROM AUTHOR]

The implementation of phytoremediation strategies under arid and semiarid climates requires the use of appropriate plant species capable of withstanding multiple abiotic stresses. In this study, we assessed the combined effects of organo-mineral amendments and microbial inoculants on the chemical and biological properties of mine tailings, as well as on the growth of native plant species under drought stress conditions. Plants were cultivated in pots containing 1 kg of a mixture of mine tailings and topsoil (i.e., pre-mined superficial soil) in a 60:40 ratio, 6% marble sludge, and 10% sheep manure. Moreover, a consortium of four drought-resistant plant growth-promoting rhizobacteria (PGPR) was inoculated. Three irrigation levels were applied: well-watered, moderate water deficit, and severe water deficit, corresponding to 80%, 45%, and 30% of field capacity, respectively. The addition of topsoil and organo-mineral amendments to mine tailings significantly improved their chemical and biological properties, which were further enhanced by bacterial inoculation and plants' establishment. Water stress negatively impacted enzymatic activities in amended tailings, resulting in a significant decrease in acid and alkaline phosphatases, urease, and dehydrogenase activities. Similar results were obtained for bacteria, fungi, and actinomycete abundance. PGPR inoculation positively influenced the availability of phosphorus, total nitrogen, and organic carbon, while it increased alkaline phosphatase, urease (by about 10%), and dehydrogenase activity (by 50%). The rhizosphere of Peganum harmala showed the highest enzymatic activity and number of culturable microorganisms, especially in inoculated treatments. Severe water deficit negatively affected plant growth, leading to a 40% reduction in the shoot biomass of both Atriplex halimus and Pennisetum setaceum compared to well-watered plants. P. harmala showed greater tolerance to water stress, evidenced by lower decreases observed in root and shoot length and dry weight compared to well-watered plants. The use of bioinoculants mitigated the negative effects of drought on P. harmala shoot biomass, resulting in an increase of up to 75% in the aerial biomass in plants exposed to severe water deficit. In conclusion, the results suggest that the combination of organo-mineral amendments, PGPR inoculation, and P. harmala represents a promising approach to enhance the phytoremediation of metal-polluted soils under semiarid conditions. [ABSTRACT FROM AUTHOR]

Water deficit is the major constraint among all stresses, which affects agricultural production worldwide. Food production is getting reduced due to drought stress which is unable to feed an ever-increasing population. The development of drought-resistant plant varieties or transgenic plants to increase food production is costly and time-consuming, also the fully adoption of new technique is not acceptable, so any sustainable way is required. The use of plant growth promoting rhizobacteria (PGPR) for the improvement of plant growth under environmental stress is a sustainable and inexpensive way. PGPRs provide various direct mechanisms like phytohormone synthesis, phosphate solubilization, nitrogen fixation, and exopolysaccharide production as well as indirect mechanisms like hydrogen cyanide, 1-aminocyclopropane-1-carboxylate deaminase, siderophore, and antibiotics production which enhances plant growth under environmental stress. Due to their multiple traits, the search for suitable and rhizosphere-competent PGPR becomes interesting and can be used as inoculants for biofertilization and biocontrol purposes in agriculture, forestry, and environmental rehabilitation. [ABSTRACT FROM AUTHOR]

Drought stress is the primary constraint on plant-based food production, particularly paddy production. Several studies have examined plant resistance to heat and osmotic pressure. This study aimed to isolate bacteria with plant growth-promoting properties that could tolerate high temperatures and improve paddy growth during drought. Five isolates with a high optical density value (OD600) at 30% PEG 6000 (equivalent to -1.03MPa) and able to grow at high temperatures were identified based on the 16S rRNA gene sequences as Achromobacter spanius UKM UR10, Bacillus pumillus UKM UR11, Bacillus cereus UKM R66, and Bacillus altitudinis UKM RB11, which were isolated from the root, where as Bacillus sp. UKM S8 was isolated from rhizosphere soil. These isolates exhibited 1-amino cyclopropane-1-carboxylate (ACC) deaminase activities ranging between 1.01 and 1.12 mmol α-ketobutyrate mg-1 protein h-1, which degraded ACC to α-ketobutyrate and ammonia. Other plant growth promoters assessed include indole acetic acid (IAA; concentration between 9.69 and 13.15µg/ml) and phosphate solubilization (concentrations between 31.74 and 51.30 mg/l) production. Subsequently, the selected plant growth-promoting rhizobacteria (PGPR) were incorporated as a consortium and inoculated on paddy seeds, thus increasing total chlorophyll, proline, and soluble sugar content in paddy subjected to drought-stress conditions. Paddy yield components and performances, such as panicle number, spikelet number, dry grain weight, number of leaves, stalk length, and root length increased significantly. This isolated PGPR exhibits heat resistance, promotes plant growth, and can serve as an inoculant for paddy plants under drought conditions. [ABSTRACT FROM AUTHOR]

Background: The severity and frequency of drought are expected to increase substantially in the coming century and dramatically reduce crop yields. Manipulation of rhizosphere microbiomes is an emerging strategy for mitigating drought stress in agroecosystems. However, little is known about the mechanisms underlying how drought-resistant plant recruitment of specific rhizosphere fungi enhances drought adaptation of drought-sensitive wheats. Here, we investigated microbial community assembly features and functional profiles of rhizosphere microbiomes related to drought-resistant and drought-sensitive wheats by amplicon and shotgun metagenome sequencing techniques. We then established evident linkages between root morphology traits and putative keystone taxa based on microbial inoculation experiments. Furthermore, root RNA sequencing and RT-qPCR were employed to explore the mechanisms how rhizosphere microbes modify plant response traits to drought stresses. Results: Our results indicated that host plant signature, plant niche compartment, and planting site jointly contribute to the variation of soil microbiome assembly and functional adaptation, with a relatively greater effect of host plant signature observed for the rhizosphere fungi community. Importantly, drought-resistant wheat (Yunhan 618) possessed more diverse bacterial and fungal taxa than that of the drought-sensitive wheat (Chinese Spring), particularly for specific fungal species. In terms of microbial interkingdom association networks, the drought-resistant variety possessed more complex microbial networks. Metagenomics analyses further suggested that the enriched rhizosphere microbiomes belonging to the drought-resistant cultivar had a higher investment in energy metabolism, particularly in carbon cycling, that shaped their distinctive drought tolerance via the mediation of drought-induced feedback functional pathways. Furthermore, we observed that host plant signature drives the differentiation in the ecological role of the cultivable fungal species Mortierella alpine (M. alpina) and Epicoccum nigrum (E. nigrum). The successful colonization of M. alpina on the root surface enhanced the resistance of wheats in response to drought stresses via activation of drought-responsive genes (e.g., CIPK9 and PP2C30). Notably, we found that lateral roots and root hairs were significantly suppressed by co-colonization of a drought-enriched fungus (M. alpina) and a drought-depleted fungus (E. nigrum). Conclusions: Collectively, our findings revealed host genotypes profoundly influence rhizosphere microbiome assembly and functional adaptation, as well as it provides evidence that drought-resistant plant recruitment of specific rhizosphere fungi enhances drought tolerance of drought-sensitive wheats. These findings significantly underpin our understanding of the complex feedbacks between plants and microbes during drought, and lay a foundation for steering "beneficial keystone biome" to develop more resilient and productive crops under climate change. FGv_ocsEwwAXXw4e-N4Vhr Video Abstract [ABSTRACT FROM AUTHOR]

A drought-resistant plant with high adaptability to various climatic and soil conditions is castor (Ricinus communis L.). There is currently a significant expectation of increased castor oil demand on the global market. When it comes to crop development, there are a variety of factors to take into account for each growing region, especially when it is preferable to fit the castor crop to specific tillage practices and intercropping system. In this veneration, the current study's goal was to determine the effects of various tillage methods and legume crop-based intercropping system in rainfed regions. The field experiments were conducted in 2021-2022 and 2022-2023 at Tapioca and Castor Research Station, Tamil Nadu Agricultural University, Yethapur. The experimental treatments consisted of conventional tillage and minimum tillage as main plot and castor based inter cropping system @ 1:3 ratio viz., Castor + Greengram, Castor + Cowpea, Castor + Groundnut and Sole Castor as subplot treatments and conducted in split plot design with three replications. The pooled results of a two-year study of different tillage practices in legume crop based intercropping systems in rainfed conditions showed no significant difference among tillage practices relevant to growth, yield attributing characters, seed yield and biomass yield, however higher values were registered under conventional tillage practices over minimum tillage. Higher seed yield of both base (1152 kg ha-1) and inter crop (481 kg ha-1) were documented in conventional tillage practices over minimum tillage. With respect to inter cropping, higher base crop (castor) yield of 1058 kg ha-1 was recorded under castor + groundnut inter cropping system, which was observed to be on par with sole castor (1020 kg ha-1), and castor + greengram (907 kg ha-1). Recorded highest Castor equivalent yield in castor + groundnut (1:3) intercropping, grown under a conventional tillage system. Moreover, the maximum benefit-cost ratio was recorded in castor + groundnut (1:3) intercropping, over sole castor cropping. The highest Castor Equivalent Yield (CEY) in a conventional tillage system was observed in a castor + groundnut (1:3) intercropping system. [ABSTRACT FROM AUTHOR]

NAC transcription factors are commonly involved in the plant response to drought stress. A transcriptome analysis of root samples of the soybean variety 'Jiyu47' under drought stress revealed the evidently up-regulated expression of GmNAC19, consistent with the expression pattern revealed by quantitative real-time PCR analysis. The overexpression of GmNAC19 enhanced drought tolerance in Saccharomyces cerevisiae INVSc1. The seed germination percentage and root growth of transgenic Arabidopsis thaliana were improved in comparison with those of the wild type, while the transgenic soybean composite line showed improved chlorophyll content. The altered contents of physiological and biochemical indices (i.e., soluble protein, soluble sugar, proline, and malondialdehyde) related to drought stress and the activities of three antioxidant enzymes (i.e., superoxide dismutase, peroxidase, and catalase) revealed enhanced drought tolerance in both transgenic Arabidopsis and soybean. The expressions of three genes (i.e., P5CS, OAT, and P5CR) involved in proline synthesis were decreased in the transgenic soybean hairy roots, while the expression of ProDH involved in the breakdown of proline was increased. This study revealed the molecular mechanisms underlying drought tolerance enhanced by GmNAC19 via regulation of the contents of soluble protein and soluble sugar and the activities of antioxidant enzymes, providing a candidate gene for the molecular breeding of drought-tolerant crop plants. [ABSTRACT FROM AUTHOR]

The paper presents a new high-resolution (up to decadal) palaeoecological evidence based on detailed AMS radiocarbon dating, plant macrofossils, testate amoebae, loss on ignition, peat humification, elemental and stable isotopic records, obtained from a palsa peatland located in vicinities of Igarka town. This gave us a unique possibility to examine the mid-to late Holocene environmental changes in a poorly investigated area in Yenisei Siberia. The obtained data show that the peatland initiation occurred at about 6350 cal yr BP by paludification of a larch forest in the conditions of climate warming and high surface wetness, possibly, due to permafrost thaw. The first sign of palsa formation occurred about 5360 cal yr BP and coincided with the temperature decrease, wetter and anoxic conditions in peatland. After several phases of uplifts (and relatively dryer conditions) and partial thawing and subsidence of its surface (wetter conditions) between 5360 and 2250 cal yr BP, the continuous rise of the perennial frost mound (up to the height of 5 m) accomplished by drying its surface and colonization by drought-resistant plant species, evidently, encouraged by the climate cooling and permafrost aggradation during the last two millennia. The high-resolution analyses of elemental (C and N) and stable isotope content (δ13C and δ15N) of the peat sequence revealed the strong linkages between the plant composition and mineralization/humification processes. Our multi-proxy study revealed detailed features of peat accumulation patterns driven by multiple interrelated allogenic and autogenic forcings, influencing changes in peat macroelement content and stable isotope composition. [ABSTRACT FROM AUTHOR]

Background: Droughts during the growing season are becoming increasingly common due to climate change and global warming. The study's goal study was to assess the adaptation mechanisms of C. coggygria Scop. under simulated water deficit conditions using indicators characterized changes in the leaf stomatal apparatus and photosynthesizing system. Methods: The influence of osmotic polyethylene glycol 6000 on the research object C. coggygria regenerants was studied in vitro. Such indicators as morphological changes, pigment content, stomatal density and size and stomatal slit size were quantified. Result: Due to the influence of osmotic stress, there was a pigment content increase in the leaf plate on osmotic media. Stomatal density raised by 27.0-29.8% in explant cells cultivated on PEG 4.0-6.0%. Under the osmotic influence, there was a drop in the stomatal cells' area and shape and the ratio of stomatal length to width in the regenerant leaves decreased from 1.5 to 1.0-1.1. These results indicate the adaptation of C. coggygria regenerants to stress caused by an artificial drought in vitro. The changes' identification in the stomatal apparatus and the C. coggygria pigment ratio will accelerate the selective screening of drought-resistant plants for use in protective forestry. [ABSTRACT FROM AUTHOR]

The gum acacia Senegalia senegal (L.) Britton (Fabales: Fabaceae) is a drought-tolerant plant belonging to the genus Acacia of the Leguminosae family, possessing significant economic and ecological value. Despite its importance, there is a knowledge gap regarding the potential impact of climate change on the distribution of S. senegal, crucial for the conservation of plant resources and optimizing its use in introductory silviculture. In this study, we selected 23 environmental variables and utilized the optimized maximum entropy (MaxEnt) model to analyze the key environmental factors affecting the distribution of S. senegal worldwide and simulate the current and future distribution range of S. senegal in Pakistan under the SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5 climate change scenarios. The results highlight key environmental factors influencing the distribution of S. senegal, including BIO3 (isothermally), BIO4 (coefficient of seasonal variation of temperature), BIO11 (mean temperature of the coldest season), and BIO12 (annual precipitation). Regions with higher and less fluctuating temperatures exhibit a higher potential for S. senegal distribution. Currently, suitable habitats of S. senegal are concentrated in the southern region of Pakistan, covering provinces such as Punjab, Sindh, and Balochistan, with highly suitable habitats accounting for 6.06% of the total area. Under the current climatic conditions, this study identifies the spatial patterns of suitable habitats and their concentration in specific regions. With climate change, a notable expansion of suitable habitats towards higher latitudes is observed, with the most significant expansion under the extremely severe climate change scenario (SSP5-8.5), reaching 223.45% of the current level. The results of this study enhance our understanding of the dynamics of S. senegal distribution under climate change and offer valuable insights into the long-term introduction of S. senegal for afforestation and soil conservation in Pakistan. This study provides theoretical support for the sustainable development of the local ecosystem and socio-economy, emphasizing the importance of proactive measures to adapt to changing climatic conditions. [ABSTRACT FROM AUTHOR]

Drought-tolerant plants have become a convenient model to study the mechanisms underlying drought tolerance in order to improve susceptible domesticated relatives. Various studies have shown that local landraces possess superior qualities that help them survive in harsh environmental conditions. One of the key mechanisms that helps with tolerance in crops is timely stomatal regulation. In this study, the physiological, morphological, and molecular stomatal responses in three drought-tolerant landraces (Clm-01–03) and hybrid (Clm-04) watermelons were evaluated under drought stress. The watermelon plants were grown under a water deficit (complete withholding of water) and non-stress conditions. The highest SPAD values were recorded for the Clm-03 and Clm-02 (50 ± 3) watermelon genotypes, and the lowest for Clm-04 (27 ± 0.37), showing this genotype's tolerance and ability to maintain its systems during drought stress. Fluorescence parameters also gave important clues to the tolerant genotypes of Clm-02 and Clm-03 under drought stress, while the domesticated genotype showed a slow response to fluorescence parameters, which could lead to damage to the photosynthesis apparatus. During the drought period, the wild watermelon was found to have a limited stomatal opening as the drought progressed, and on day 9, it had the smallest opening of 23.1 ± 1.2 µm compared to any other genotype; most importantly, upon re-watering, it showed more rapid recovery than any other genotype. This was also expressed by mRNA quantification of stomatal aperture TFs, with an eight-fold increase in Cla004380 TFs recorded for wild watermelon. All of these mechanisms have been attributed to the tolerance mechanisms of the drought-tolerant watermelon genotype. This study provides important insight into the stomatal responses of probable tolerant watermelon accessions and suggests that improving the stomatal aperture of susceptible domesticated species would also improve their tolerance. [ABSTRACT FROM AUTHOR]

This study aimed to reveal the soil reinforcement by shrub root systems after repeated stress from external forces, such as high winds and runoff, for extended periods in the wind-hydraulic compound erosion zone. Using the widely distributed Shandong mine area soil and water-conserving plant species, Caragana microphylla, Hippophae rhamnoides, and Artemisia ordosica, cyclic loading tests were conducted on taproots of the three plant species (1–5 mm diameter) via a TY8000 servo-type machine to investigate the taproots' tensile properties response to repeated loading–unloading using simulated high wind pulling and runoff scouring. Our study revealed that the tensile force was positively correlated with the root diameter but the tensile strength was negatively correlated under monotonic and cyclic loading of the three plants' taproots. However, after cyclic loading, the three plant species' taproots significantly enhanced the tensile force and strength more than monotonic loading (P < 0.05). The taproot force–displacement hysteresis curves of the three plant species revealed obvious cyclic characteristics. Structural equation modeling analysis revealed that root diameter and damage method directly affected the taproots' survival rate, reflecting their sustainable soil reinforcement capacity. The damage method significantly influenced the soil reinforcement more than the root diameter. Our findings reveal that the plant species' taproots can adapt more to the external environment and enhance their resistance to erosion after natural low perimeter erosion damage, effectively inducing soil reinforcement. Particularly, the taproots of Caragana microphylla have superior soil-fixing ability and can be used for ecological restoration. [ABSTRACT FROM AUTHOR]

BdGF14a, a 14-3-3 gene from Brachypodium distachyon, induced by salt, H2O2, and abscisic acid (ABA), improved tolerance to drought and salt in tobacco, with a higher survival rate and longer roots under these stresses. Additionally, physiological index analyses showed that the heterologous expression of BdGF14a induced higher expression levels of antioxidant enzymes and their activities, leading to lighter DAB and NBT staining, denoting decreased H2O2 content. Additionally, the lower MDA content and ion leakage indicated enhanced cell membrane stability. Moreover, exogenous ABA resulted in shorter roots and a lower stomatal aperture in BdGF14a transgenic plants. BdGF14a interacted with NtABF2 and regulated the expression of stress-related genes. However, adding an ABA biosynthesis inhibitor suppressed most of these changes. Furthermore, similar salt and drought resistance phenotypes and physiological indicators were characterized in tobacco plants expressing BdbZIP62, an ABRE/ABF that interacts with BdGF14a. And Y1H and LUC assays showed that BdGF14a could enhance the transcription regulation activity of NtABF2 and BdbZIP62, targeting NtNECD1 by binding to the ABRE cis-element. Thus, BdGF14a confers resistance to drought and salinity through interaction with BdbZIP62 and enhances its transcriptional regulation activity via an ABA-mediated signaling pathway. Therefore, this work offers novel target genes for breeding salt- and drought-tolerant plants. [ABSTRACT FROM AUTHOR]

Drought-resistant plants exhibit strong water retention capability. In this regard, the autotetraploid sour jujube leaves exhibit better water retention than diploid leaves. Morphological comparisons and physiological comparisons of diploid and autotetraploid leaves showed that the autotetraploid leaves had thicker leaf cuticles and more leaf wax accumulation than the diploid leaves, which could reduce cuticle permeability and improve the drought tolerance of leaves. In this study, the cuticular wax crystalloids on the adaxial and abaxial sides of young and mature jujube leaves were observed in the two ploidy types, and unique cuticular wax crystalloids covering a large area of the cuticle on autotetraploid sour jujube leaves may provide an advantage in reducing leaf non-stomata transpiration and improving plant drought tolerance. Based on the transcriptome, 115 differentially expressed genes between diploids and autotetraploids were further analyzed and found to be involved in the accumulation of cuticular wax components, including terpenoids, fatty acids, and lipids, as well as ABC transporter and wax biosynthetic process. Finally, 14 genes differentially expressed between glossy autotetraploid leaves and nonglossy diploid leaves, such as LOC107414787, LOC107411574 and LOC107413721, were screened as candidate genes by qRT-PCR analysis. This findings provided insights into how polyploidization improved drought tolerance. [ABSTRACT FROM AUTHOR]

This study investigated the effect of drought stress on the expression of chloroplast genes in two different genotypes (A1 and A4) of strawberry tree plants with contrasting performances. Two-year-old plants were subjected to drought (20 days at 18% field capacity), and the photosynthetic activity, chlorophyll content, and expression levels of 16 chloroplast genes involved in photosynthesis and metabolism-related enzymes were analyzed. Genotype-specific responses were prominent, with A1 displaying wilting and leaf curling, contrasting with the mild symptoms observed in A4. Quantification of damage using the net CO2 assimilation rates and chlorophyll content unveiled a significant reduction in A1, while A4 maintained stability. Gene expression analysis revealed substantial downregulation of A1 (15 out of 16 genes) and upregulation of A4 (14 out of 16 genes). Notably, psbC was downregulated in A1, while it was prominently upregulated in A4. Principal Component Analysis (PCA) highlighted genotype-specific clusters, emphasizing distinct responses under stress, whereas a correlation analysis elucidated intricate relationships between gene expression, net CO2 assimilation, and chlorophyll content. Particularly, a positive correlation with psaB, whereas a negative correlation with psbC was found in genotype A1. Regression analysis identified potential predictors for net CO2 assimilation, in particular psaB. These findings contribute valuable insights for future strategies targeting crop enhancement and stress resilience, highlighting the central role of chloroplasts in orchestrating plant responses to environmental stressors, and may contribute to the development of drought-tolerant plant varieties, which are essential for sustaining agriculture in regions affected by water scarcity. [ABSTRACT FROM AUTHOR]

Understanding the tolerance of plants to drought and their gradual response to lack of water is a multifaceted challenge that requires a combination of scientific research and technological innovation. Selecting naturally drought-tolerant plants and knowing their response to photosynthesis in a wide range of water availability opens a door to making decisions about the suitability of different cultivars to be implanted in specific geographical areas, based on their tolerance to drought and light absorption capacity. In this work, photosynthesis–light curves were carried out using a LiCor LI-6800 IRGA device, applying increasing light intensities to plants of 14 olive cultivars, either under control conditions (no water stress) or subject to moderate and severe water deficits. The plants were grown in a culture chamber under controlled conditions for photoperiod, air humidity, temperature, and carbon dioxide concentration. For each cultivar, the electronic transference ratio (ETR) in response to light was also obtained. Different equations were used to fit experimental data allowing us to calculate, with a regression coefficient above 0.95, different photosynthetic parameters such as the maximum photosynthetic capacity, the photosynthetic efficiency, the number of electrons or the number of photons to assimilate a molecule of CO2, and the effect of the lack of water on these parameters. This work represents the first contribution of the response to photosynthesis of many olive cultivars subjected to moderate and severe drought conditions. The parameters described, and the results provided, pave the road for subsequent work related to plant physiology and other areas of science and technology, and allow us to objectively compare the tolerance to water stress in these fourteen olive cultivars. [ABSTRACT FROM AUTHOR]

Using native species for urban green space is rather important nowadays. Plant cover on soil is necessary for agronomical and architectural investments as well as conservational programs, which all need minimal maintenance and have to be cost efficient. Commercially available seed mixtures for grasslands and lawns include species that partly originated from other mesoclimatic zones, and thus they may not be able to survive in the long-term, nor will they be adventive to the local ecosystem. With a focus on climate change, the most arid part of the Pannon geographical region was selected (near Törökszentmiklós in Nagykunság, Hungarian Great Plain). The local flora has adapted effectively to the environment; therefore, many species growing there were candidates for this study. Annuals and herbaceous perennials were investigated with respect to harvestability, reproducibility, decorativity, seed production, seed morphological characters (size, mass) and germination features. The selected 20 taxa were inoculated with INOQ Agri mycorrhiza (Rhizophagus irregularis) to increase the drought tolerance and biomass of the plants. Mycorrhizal frequency was significantly different among the taxa, reflecting various responses to the symbiotic interaction and possibly various mycorrhizal dependence of the plant species examined. We did not observe significantly higher colonization rate in most cases of the samples with artificial inoculation treatment. We conclude that the degraded mowed lawn soil that we used could contain propagules of AM fungi in a sufficient amount, so in the artificial grassland restorations, the additional AM inoculation treatment is not necessary to achieve a higher AM colonization rate. [ABSTRACT FROM AUTHOR]

The influence of feeding a new hybrid of sorghum (ES Shamal, orange variety) in broiler chickens on growth, health, meat, and litter quality was evaluated from 1–42 d. A total of 360-day-old male Ross 308 broiler chicks (40.1 ± 2.3 g) were randomly assigned to 3 experimental diets: 100% corn-based diet (S0), partial replacement of corn with 50% sorghum (S50), total replacement of corn with sorghum (S100). All diets were calculated to be isonitrogenous and isocaloric with similar content of total lysine, total sulphur amino acids, calcium, and available phosphorous. The results indicated that partial or total replacement of corn by sorghum is suitable for broiler chicken diets with no adverse effects on growth, and slaughter performance, as well as litter quality over the whole trial period. Moreover, the substitution of corn with sorghum, reduced (p =.007) abdominal fat associated with an increase in breast and thigh meat colour (L* values; p <.001). Also, a significant (p =.002) decrease in plasma triglyceride was found in broilers fed sorghum-based diets. Except for collagen and hardness in the breast and thigh, and gumminess only in the thigh muscle, there were no differences in fundamental physicochemical (pH, protein, fat, moisture) or textural attributes of meat due to dietary treatment. However, sorghum alters the intestinal microflora, resulting in a lower count of E. coli in the caeca. It can thus, be concluded that sorghum (ES Shamal, orange variety) can be included in broiler feeds from hatching to day 42, without any adverse effects on the broiler's performance. Climate changes become a threat to the livestock sector and finding novel nutritional solutions for feeding farm animals became a priority. New sorghum varieties are valuable in terms of drought-resistant plants. Replacement of corn with sorghum in broiler diets maintains growth performances and carcase characteristics. [ABSTRACT FROM AUTHOR]

Green foxtail (Setaria viridis) is a notorious weed in corn fields in Heilongjiang Province. To investigate the best method to break the seed dormancy of green foxtail and its physiological response to topramezone, this study selected newly harvested and one-year stored green foxtail seeds as research subjects. The seeds were treated with HCl, NaOH, gibberellic acid (GA), different water temperatures and polyethylene glycol (PEG) to study the seed dormancy and drought resistance of green foxtail. The results showed that newly harvested seeds exhibited dormancy, and treatments with HCl, NaOH and different water temperatures were unable to break the dormancy. Soaking the seeds in GA could overcome dormancy, but the seeds failed to germinate when exposed to 25% PEG concentration. When topramezone was applied at rates of 22.5 and 45.0 g a.i. • hm-2 at the 3-leaf and 5-leaf stages, respectively, the chlorophyll content reached the lowest value at 28 days after treatment (DAT). At the 7-leaf stage, the chlorophyll content reached the lowest value at 7 DAT. The activity of 4-hydroxyphenylpy-ruvate dioxygenase (HPPD) enzyme after topramezone application reached the maximum value at 7 DAT for different leaf ages, and the higher the leaf age, the higher the HPPD activity, which was an important factor contributing to the resistance of green foxtail to topramezone. [ABSTRACT FROM AUTHOR]

Drought has become one of the main factors of crop yield losses worldwide. This negatively affects the plant industry, decreasing crop yields, and it may result in resource deficits in different sectors of the world economy and its national branches. Guar (Cyamopsis tetragonoloba (L.) Taub) represents one of the strategic crops, as its seeds are the source of guar gum, which is critically important in the modern oil industry. Although guar is generally known to be a drought-tolerant plant, it is known that soil dehydration negatively affects plant fitness and crop productivity. As guar genotypes are characterized by high variability in the manifestation of drought tolerance, screening genetic resources for this feature seems to be a promising strategy for accessing drought-resistant varieties. The discovery of drought-tolerant genotypes is mandatory to secure sustainable guar production. In this context, the identification of reliable chemical and molecular markers of drought tolerance (i.e., drought-responsive and/or drought-protective metabolites, proteins and transcripts) will provide the solid basis for marker-driven breeding of new tolerant varieties. Therefore, here we provide a comprehensive overview of the available literature data on guar drought stress response, its physiological and molecular genetic aspects, and considerations on the approaches to improve the quality of this crop. [ABSTRACT FROM AUTHOR]

Drought severely slows down plant growth, decreases crop yield, and affects various physiological processes in plants. We examined four local bread wheat cultivars with different drought tolerance (drought-tolerant Zirva 85 and Murov 2 and drought-sensitive Aran and Gyzyl bughda cultivars). Leaves from seedlings of drought-tolerant plants demonstrated higher activity of antioxidant enzymes and lower levels of malondialdehyde and hydrogen peroxide. The content of soluble proteins in drought-exposed increased, possibly due to the stress-induced activation of gene expression and protein synthesis. Drought-exposed Zirva 85 plants exhibited an elevated activity of nitrogen and carbon metabolism enzymes. Ultrastructural analysis by transmission electron microscopy showed drought-induced damage to mesophyll cells and chloroplast membranes, although it was manifested less in the drought-tolerant cultivars. Comparative analysis of the activity of metabolic and antioxidant enzymes, as well as observed ultrastructural changes in drought-exposed plants revealed that the response to drought of seedlings was more pronounced in drought-tolerant cultivars. These findings can be used in further studies of drought stress in wheat plants under natural conditions. [ABSTRACT FROM AUTHOR]

Background. Okra is a plant farmed for its pods, leaves, and stems all of which are edible. It is famous for its ability to tolerate long desiccation periods. It belongs to the Malvaceae family and is a sister species to hibiscus, cotton, and cacao plants. Methods. In the current study, okra plants were used as a model to sequence, assemble, and analyze the evolutionary and functional characteristics of the Dicer-like protein gene family (DCL) based on DNAseq and qPCR techniques. Results. Four Dicer-like (DCL) single-copy genes of the okra plant Abelmoschus esculentus (L.) Moench (AeDCL) were successfully assembled. The lengths of the AeDCL copies were 8,494, 5,214, 4,731, and 9,329 bp. The detected exons in these samples ranged from a single exon in AeDCL3 to 24 exons in AeDCL4. AeDCLs had five functional domains of two DEAD-like helicase superfamilies, N and C; one Dicer domain; one ribonuclease III domain (a and b); and one double-stranded RNA-binding domain. The PAZ domain was completely annotated only for AeDCL1 and AeDCL3. All AeDCLs were up-regulated under drought conditions, with leaves showing more extensive fold changes than roots. The study focused on a comprehensive genomewide identification and analysis of the DCL gene family in naturally drought-tolerant okra plants, an orphan crop that can be used as a model for further genomic and transcriptomic studies on drought-tolerance mechanisms in plants. [ABSTRACT FROM AUTHOR]

Stomata are involved in transpiration and CO2 uptake by mediating gas exchange between internal plant tissues and the atmosphere. The capacity for gas exchange depends on stomatal density (SD), stomatal size, and pore dimensions. Most published work on stomatal quantification has assumed that stomatal distribution and stomatal density are spatially homogeneous across the leaf, but this assumption has been seldom tested. We selected 32 leaves from a Photinia hybrid, Photinia × fraseri 'Red Robin', and one of its parents, P. serratifolia. For each leaf, the leaf surface was divided into three or four equidistant layers along the apical–basal axis, and, in each layer, two positions, one closer to the midrib and the other closer to the leaf margin, were further selected. We calculated SD and mean nearest neighbor distance (MNND) for each lamina section and tested the scaling relationship between SD and MNND of the sampled stomatal centers using reduced major axis protocols. In addition, we calculated the stomatal aggregation index (SAI) for each lamina section to examine the spatial arrangement of stomata at the given size of field of view of 1.2 mm × 0.9 mm. We observed that SD decreased from the lamina apex towards the base for central lamina areas but varied little at leaf margins. An inverse scaling relationship between SD and MNND was observed for both species. This relationship could be used for SD estimation using the rapidly estimated trait, MNND. SAI did not vary significantly throughout leaf lamina, and the numerical values of SAI for all fields of view were greater than one, which indicates significant spatial repulsion between stomata. The study suggests that SD varies across leaf lamina to fine-tune plant water use and maximize carbon gain. However, spatial structures of stomata from different lamina sections exhibit similar patterns (i.e., spatial inhibition between stomata at small scales), probably due to hierarchical leaf vein patterns. [ABSTRACT FROM AUTHOR]

Ellagic acid (EA) has gained momentum recently due to its various properties like anti‐mutagenic, anti‐carcinogenic, anti‐oxidant, anti‐viral and many other benefits to human health. The present study focused on the microbial production of EA from mango pulp processing industrial waste as an alternate method for conventional chemical extraction. Our experiments demonstrated that the 100 μg/mL of EA was produced by Micrococcus luteus from 9% of mango pulp waste and the effect of several fermentation parameters of EA production with Pontecorvo medium has yielded 496.75 mg/g at pH 6.0, temperature 35°C, ammonium nitrate (nitrogen source), sucrose (carbon source), potassium chloride (mineral source) with 0.5% of inoculum after 48 h of incubation. EA synthesized was further confirmed with the standard EA in high performance liquid chromatography and Fourier transform infrared spectroscopy. Perspective approaches like drought resistant in plants, anti‐parasitic activity and anti‐cancer activities have been proven and they were docked against depression proteins (receptors), namely MAO‐A using Epic, LigPrep and Glide module of Schrödinger. EA was found to have an ability to bind with the candidate receptor proteins 2Z5X for depression. Microbial bioconversion of mango wastes from pulp processing industries which can reduce the environmental pollution and convert as value added product. [ABSTRACT FROM AUTHOR]

Globally, we are facing an emerging climate crisis, with impacts to be notably felt in semiarid regions across the world. Cultivation of drought‐adapted succulent plants has been suggested as a nature‐based solution that could: (i) reduce land degradation, (ii) increase agricultural diversification and provide both economic and environmentally sustainable income through derived bioproducts and bioenergy, (iii) help mitigate atmospheric CO2 emissions and (iv) increase soil sequestration of CO2. Identifying where succulents can grow and thrive is an important prerequisite for the advent of a sustainable alternative 'bioeconomy'. Here, we first explore the viability of succulent cultivation in Africa under future climate projections to 2100 using species distribution modelling to identify climatic parameters of greatest importance and regions of environmental suitability. Minimum temperatures and temperature variability are shown to be key controls in defining the theoretical distribution of three succulent species explored, and under both current and future SSP5 8.5 projections, the conditions required for the growth of at least one of the species are met in most parts of sub‐Saharan Africa. These results are supplemented with an analysis of potentially available land for alternative succulent crop cultivation. In total, up to 1.5 billion ha could be considered ecophysiologically suitable and available for succulent cultivation due to projected declines in rangeland biomass and yields of traditional crops. These findings may serve to highlight new opportunities for farmers, governments and key stakeholders in the agriculture and energy sectors to invest in sustainable bioeconomic alternatives that deliver on environmental, social and economic goals. [ABSTRACT FROM AUTHOR]

Ornamental rhizoma peanut (Arachis glabrata Benth.; ORP) is a low-maintenance groundcover for use in urban and residential landscapes. Despite its availability since 2002, consumer insights on ORP have never been assessed. Online surveys are readily accepted by academic researchers as a valuable research tool. An online survey was distributed to 5820 Floridians with the objective to assess the use and perceptions of ORP by consumers. A total of 907 survey responses were received. Most respondents identified themselves as home gardeners (89%), white (93%), female (75%), and over age 65 (60%). Out of several turfgrass alternative benefits, respondents most valued reducing herbicide/pesticide and fertilizer/water usage and preventing weed establishment (X² = 204, df = 6, P < 0.001). The ORP selection purchased by respondents was predominately unknown. Most preferred ORP to flower heavily and frequently and maintain a canopy height below 20 cm in the landscape with infrequent mowing. Survey data show there is a potentially large consumer demand for ORP in Florida, but product availability, branding, and consumer access and engagement with information sources require additional focus in the coming years. [ABSTRACT FROM AUTHOR]