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The paper presents a detailed ecological investigation of mangroves (trees and palm) along Carigara Bay in Leyte, Philippines by comparing the diversity, vegetation structure, species composition, and indicator species among forest types (riverine and fringe) and zones (landward, middleward, and seaward/along water) as well as by examining their relationships with environmental variables. A total of 22 mangrove species, belonging to 12 families were documented wherein the most abundant was Sonneratia alba, followed by Nypa fruticans, then by Avicennia rumphiana. It was found that the diversity (Shannon-Wiener) of riverine mangroves (0.94 ± 0.07; 1.20 ± 0.04) was significantly higher than the fringe at the middleward and seaward/along the water (p < 0.001). In the fringe mangrove forests, the mangrove species Aegiceras corniculatum was associated with the middleward zone, and Camptostemon philippinensis, Aegiceras floridum, Rhizophora mucronata, Sonneratia alba, and Lumnitzera littorea were associated with the seaward zone, whereas landward zone of fringe and all the zones in riverine were generally associated by species with low to optimum salt tolerances such as Nypa fruticans, and Avicennia rumphiana as the most abundant. As well, a total of 14 mangroves have been identified as indicator species. Lastly, mangrove species can be generally classified as riverine and fringing based on the environmental factors explaining their distributions, and it has been found that soil porosity, water content, soil salinity, and distance from the sea or river's edge were the most significant environmental factors that determine diversity patterns. [ABSTRACT FROM AUTHOR]

Soil salinity is increasing due to several factors such as climate change and areas with uneven rainfall. This increase in level of salinity compelled the cotton breeders to develop a new germplasm that exhibit the suitable for salty soil. This study aimed to determine the salt tolerance of 50 accessions of Gossypium hirsutum in hydroponic conditions having three levels of NaCl, i.e., 0 mM, 150 mM, and 200 mM. The experiment was carried out in a completely randomized design with a factorial arrangement. Morphological, physiological, and biochemical attributes were estimated in these genotypes. The Na+/K+ ratio was determined by dry digestion method. Salt-susceptible and -tolerant genotypes were identified by biplot and cluster analysis. The genotypes showed significant differences for morphophysiological and biochemical parameters. In control, Cyto-515 showed enhanced growth with shoot length (30.20 cm), root length (20.63 cm), fresh shoot weight (2.34 g), and fresh root weight (0.93 g), while under 150 mM and 200 mM salinity levels, MNH-992 had the maximum root length (15.67 cm) and shoot length (24.67 cm). At a 150 mM salinity level, maximum levels of antioxidants were found in Kehkshan and CIM-595, while at a 200 mM salinity level, AA-703, CIM-595, and Kehkshan showed maximum values of antioxidants. The highest Na+/K+ ratio was observed in VH-363 and FH-114, while Kehkshan had lowest Na+/K+ ratio. The biplot analysis revealed that Kehkshan, CIM-595, VH-330, Cyto-178, MNH-992, and Cyto-515 were widely dispersed and distant from the origin, and exhibiting variability for morphophysiological and biochemical traits under the salt stress. In terms of performance across the treatments, accessions MNH-992, Kehkshan, Cyto-515, and CIM-595 performed significantly better. Peroxidase activity, proline contents, H2O2 determination, and Na+/K+ ratio were shown to be useful for the salt tolerance selection criteria. The potential of such salt tolerant accessions (MNH-992, Kehkshan, Cyto-515, and CIM-595) could be assessed after planting in salt affected areas and could be used in breeding programs for the development of diverse salt tolerant new genotypes of upland cotton. [ABSTRACT FROM AUTHOR]

In this study, a salt-tolerant friction reducer was proposed on the basis of dispersion polymerization to recycle high-salinity produced water. A dispersion polymerization friction reducer (DPFR) was synthesized using an acrylamide copolymer in an ultra-high-salinity solution, and its friction reduction performance was simulated in produced water. The gel permeation chromatography revealed that DPFR exhibited high molecular weight and low dispersity could stretch rapidly and show hydration in 2 s. Thus, the proposed reducer exhibits considerable potential for fracturing friction reduction. These performance tests were primarily conducted using a closed-loop flow system at various bulk velocities, dosages, and salt contents; therefore, the experimental results revealed that 2000 ppm DPFR exhibited the maximum slickwater friction reduction efficiency (FRe) of approximately 80% at 40 L/min. Furthermore, DPFR retained a high friction reduction performance of more than 75% at concentration of 120 g /L Na+, 100 g/L Ca2+, 20 g/L Fe3+, 180 g/L Cl−, and 100 g/L SO42- solutions. Functional tests revealed that novel DPFR exhibited a high salt tolerance in various high-salinity produced waters. Furthermore, DPFR is economical, environment-friendly and operationally efficient, because no additional organic additive is required in the synthesis and application process. [ABSTRACT FROM AUTHOR]

Very few Solanaceae species are able to grow in saline soils; one of them is Lycium humile. This species is endemic to the Altiplano-Puna region (Central Andes, South America) where there are multiple extreme environmental conditions such as hypersaline soils. Here we present an updated description and distribution of L. humile including its new record for Bolivia at the edges of "Salar de Uyuni", the largest salt flat in the world; we discuss its ecological role in saline environments by analyzing soil salinity and coverabundance values of the studied sites. According to IUCN criteria, we recommend a category of Least Concern for L. humile, but the growing development of lithium mining in saline environments of the Altiplano-Puna region may potentially threaten exclusive communities. [ABSTRACT FROM AUTHOR]

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Saline area may tend to be a productive land; however, many of salt-affected soils have nitrogen limitation and depend on plant-associated diazotrophs as their source of 'new' nitrogen. Herein, a total of 316 salinity tolerant nitrogen-fixing endophytic bacteria were isolated from roots of the halophyte Suaeda sp. sampled from 22 different areas of Iran to prepare the collection of nitrogen-fixing bacterial endophytes and evaluate the plant growth–promoting effect of effective isolates on growth of the halophyte Suaeda maritima. All of the identified nitrogen-fixing endophytes were classified to Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes phylum while we did not detect common nitrogen-fixing endophyte of glycophytes like Azospirillum. The genera Pseudomonas and Microbacterium were both encountered in high abundance in all samples, indicating that they might play an advanced role in the micro-ecosystem of the halophyte Suaeda. In addition, the results also showed that not only soil salinity can affect halophyte endophytic composition but also other factors such as geographical location, plant species, and other soil properties may be involved. Interestingly, only Zhihengliuella halotolerans and Brachybacterium sp. belonging to Actinobacteria could grow in semi-solid N-free (NFb) medium supplemented with 6% NaCl and highly enhanced growth of S. maritima in vitro. Overall, this study offers useful new resources for nitrogen-fixing endophytic bacteria which may be utilized to improve approaches for providing bio-fertilizer useful in saline-based agriculture. [ABSTRACT FROM AUTHOR]

• Salinity tolerance of five wild grapevine populations was investigated. • Only one wild grapevine population (Sylv5) was able to germinate at 250 mM NaCl. • The ability of seeds to recover their germination greatly varied among populations. • Wild grapevine able to salinity tolerance could be used as rootstock. Wild grapevine [ Vitis vinifera L. subsp. sylvestris (Gmelin) Hegi], belonging to the Vitaceae family, is the ancestor of cultivated grapevine varieties (Vitis vinifera L. subsp. vinifera) and is considered an important Crop Wild Relative (CWR). The response to different levels of saline stress (0, 125, 250, 500 mM NaCl) during the seed germination phase of five populations was evaluated, as well as the potential ability of seeds to recover their germination after the salt exposure. The maximum level of salt in which seeds were able to germinate was 250 mM NaCl, except for the population of Sylv3, which did not germinate at more than 125 mM NaCl. Great inter-populational variability was detected among the other four population ns that germinated at up to 250 mM NaCl, and each of them showed a preferential temperature in this pattern. The ability of seeds to recover their germination after the salt stress greatly varied among populations and as a function of the salinity concentration to which seeds were exposed in the previous phase. No more than ca. 30% of wild grapevine seeds recovered after being sown at 500 mM NaCl, but up to 95% had the ability to recover after 250 mM, showing that seeds of this taxon could tolerate moderate salinity levels in the soil and have successful recovery after rainfalls. Our findings could help in understanding the actual distribution and ecophysiology of the wild grapevine in the Mediterranean area and could be useful in the selection of populations with more salt-tolerant plants that could be used as rootstock for the cultivation of grapevines in areas near to the coastline or salinized soils, where salinity is an important limiting factor. [ABSTRACT FROM AUTHOR]

Saline soils are scattered within multiple inland basins in the semi-arid, rain shadow areas of the South Island, New Zealand. Competing land use activities in agriculture, mining, viticulture and human habitation have led to a strong decline in saline soils to an estimated < 1% of their original distribution. Small areas of ‘new’ (decades old) salinity have arisen at some highly modified sites but these are poorly understood in relation to older saline soils. Recent information from fine-scale geological surveys and geochemical analysis of substrates at two Department of Conservation scientific reserves in Central Otago, with specialist saline flora, is presented in a short synthesis. The goal is to amend existing viewpoints on plant–substrate interactions at what are abandoned gold mine sites. The current surface conditions at Springvale Reserve and Chapman Road Reserve, near Alexandra, which have developed acute salinity during the last 100 years since mining ceased, are outlined. The process of salt accumulation at each site is also clarified and seeks to rectify previous views on local salt source. The new geological data can inform conservation management of the sites, to better address the overall decline of saline habitat for indigenous plant species. A new adaptive management approach is proposed for each reserve that essentially harnesses effects of physical processes, to secure botanical values in the near future. [ABSTRACT FROM AUTHOR]

Background: Soil salinity is a significant factor that impairs plant growth and agricultural productivity, and numerous efforts are underway to enhance salt tolerance of economically important plants. Populus species are widely cultivated for diverse uses. Especially, they grow in different habitats, from salty soil to mesophytic environment, and are therefore used as a model genus for elucidating physiological and molecular mechanisms of stress tolerance in woody plants. Description: The Salinity Tolerant Poplar Database (STPD) is an integrative database for salt-tolerant poplar genome biology. Currently the STPD contains Populus euphratica genome and its related genetic resources. P. euphratica, with a preference of the salty habitats, has become a valuable genetic resource for the exploitation of tolerance characteristics in trees. This database contains curated data including genomic sequence, genes and gene functional information, non-coding RNA sequences, transposable elements, simple sequence repeats and single nucleotide polymorphisms information of P. euphratica, gene expression data between P. euphratica and Populus tomentosa, and whole-genome alignments between Populus trichocarpa, P. euphratica and Salix suchowensis. The STPD provides useful searching and data mining tools, including GBrowse genome browser, BLAST servers and genome alignments viewer, which can be used to browse genome regions, identify similar sequences and visualize genome alignments. Datasets within the STPD can also be downloaded to perform local searches. Conclusions: A new Salinity Tolerant Poplar Database has been developed to assist studies of salt tolerance in trees and poplar genomics. The database will be continuously updated to incorporate new genome-wide data of related poplar species. This database will serve as an infrastructure for researches on the molecular function of genes, comparative genomics, and evolution in closely related species as well as promote advances in molecular breeding within Populus. The STPD can be accessed at http://me.lzu.edu.cn/stpd/. [ABSTRACT FROM AUTHOR]

Approximately, 20% of arable land worldwide, as well as nearly half of irrigated land, is subjected to salt stress. Osmotic stress and ion toxicity due to saline soils cause low crop yields. In this study, we introduced 18 families of salt-tolerant birch (Betula pendulaRoth.,Betula kirghisorumSav.-Ryczg., andBetula pubescensEhrh) into five high-salinity locations in northeastern China and evaluated their survival abilities. We also analyzed variation and stability of genotype–environment interactions of the different families under an additive main effect and multiplicative interaction model. Survival rate analysis indicated that the introduced families were well adapted to the high-salinity environments, whereas native families died. Variation analysis revealed significant differences between location × family interaction mean values for height and basic stem diameter (BSD), suggesting that most genotypes responded differently to different sites. The heritability of tree height and BSD at different sites varied from 0.416 to 0.940, with the coefficient of phenotypic variation ranging from 9.88% to 35.53%. Stability analysis indicated that some families had high tree heights but were sensitive to environmental conditions, whereas others were resistant but had average tree heights. These results suggest that families should be bred in various habitats to assess growth under favorable and unfavorable environments. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) disease caused by Fusarium graminearum (Fg) seriously affects the yield and quality of wheat. In this study, after bacterial community analysis of two wheat rhizosphere soils, the genus Pseudomonas was shown to be enriched in normal dry farmland (maize-wheat rotation) compared to that observed nearby paddy farmland (rice-wheat rotation) with serious FHB disease. Subsequently, a P. aeruginosa strain, NF011 with the highest antagonistic activity against Fg and excellent tolerance to 8.0 % of NaCl was isolated from the wheat rhizosphere soil in the normal dry farmland. Dual culture assay results showed that NF011 is a broad-spectrum fungicide for controlling six wheat pathogenic fungi. The major antifungal compound produced by NF011 was identified as phenazine-1-carboxamide (PCN) by LC–MS and nuclear magnetic resonance. 1.0 × 108 CFU/mL of NF011 or 32 mg/L of PCN could completely inhibit Fg spore germination and resulted in the destruction of Fg hypha vacuoles. Mannitol, peanut meal, beef extract, metal ions (Mn2+, Ca2+, Fe2+, and Mg2+), and amino acids (Arg and Lys) could promote the production of PCN by NF011, moreover, the optimal pH and temperature was 6.0 and 20 °C. The PCN produced by NF011 under the optimized culture conditions reached 436.55 ± 11.06 mg/L, 4.90-fold higher than that observed under the basic culture conditions. Finally, infection experiment results showed that NF011 can effectively prevent Fg spores from infecting wheat spikes and wheat grains and suppress the production of deoxynivalenol (DON). Therefore, the salt-tolerant PCN-producing NF011 has the potential to control wheat fungal disease. [ABSTRACT FROM AUTHOR]

• Action mechanisms of halotolerant bacteria in alleviating salinity stress in plants were highlighted. • The most predominant halotolerant genera belonged to Halomonas , Bacillus , Streptomyces , Oceanobacillus , and Pseudomonas. • The most predominant halotolerant antagonistic bacteria genera belonged to Bacillus , Streptomyces , and Halomonas. • Most of the halotolerant bacteria were positive for IAA and ACC deaminase production, as the most important PGP traits. • Research needs about the use of halotolerant bacteria under salinity stress were highlighted. As one of the major non–biological stresses, soil salinity negatively affects agricultural productivity, microbial communities, and agricultural economics in impacted areas and is a significant agrarian problem worldwide that has expanded in the last few decades. The use of glycophytes (salt–sensitive plants) is the primary limitation to such an agricultural approach. However, halophytes, which are proficient at obtaining essential micro/macronutrients from exceedingly saline environments and thrive under conditions in which salinity–sensitive crops are either unproductive or inefficient, are prime candidates for utilization in these circumstances. In addition, the bacterial microbiome associated with the roots of halophytic plants is a useful resource for the isolation of salt–tolerant bacteria with multiple plant growth–promoting characteristics, such as the production of different phytohormones, dissolution of insoluble inorganic phosphates, siderophore production, molecular nitrogen fixation, the activity of 1–aminocyclopropane–1–carboxylic acid (ACC) deaminase enzyme, and pathogen suppression, which enhance salinity tolerance of these plants as well as glycophytes and thereby stimulate the growth of plants under salinity–induced stress. The most dominant among reported halotolerant bacterial genera in most of the halophytic plants are Halomonas , Bacillus , Streptomyces, Oceanobacillus , and Pseudomonas. Here, it is shown that a wide range of halotolerant bacteria with a variety of plant growth-promoting characteristics may provide an important resource for augmenting crop tolerance to salinity and thereby boosting saline soil–based agriculture. [ABSTRACT FROM AUTHOR]

Salt-tolerant plant growth-promoting rhizobacteria (PGPR) could be an alternative to alleviate salinity problems in rice plants grown in the coastal areas. This study was conducted to isolate and characterize salt-tolerant PGPR and observe their effects on the physiological and biochemical properties of rice plants grown under non-saline and saline glasshouse conditions. Three strains were selected based on their salt-tolerance and plant growth-promoting properties under in vitro saline conditions. These strains were identified as Bacillus tequilensis (UPMRB9), Bacillus aryabhattai (UPMRE6), and Providencia stuartii (UPMRG1) using a 16S rRNA technique. The selected strains were inoculated to three different rice varieties, namely BRRI dhan67 (salt-tolerant), Putra-1 (moderate salt-tolerant), and MR297 (salt-susceptible) under glasshouse conditions. Results showed that the MR297 rice variety inoculated with UPMRB9 produced the highest total chlorophyll content, with an increment of 28%, and lowest electrolyte leakage of 92%. The Putra-1 rice variety also showed a 156% total dry matter increase with the inoculation of this bacterial strain. The highest increase of relative water content and reduction of Na/K ratio were found upon inoculation of UPMRE6 and UPMRB9, respectively. The biggest significant effects of these bacterial inoculations were on relative water content, electrolyte leakage, and the Na/K ratio of the BRRI dhan67 rice variety under saline conditions, suggesting a synergistic effect on the mechanisms of plant salt-tolerance. This study has shown that the application of locally-isolated salt-tolerant PGPR strains could be an effective long-term and sustainable solution for rice cultivation in the coastal areas, which are affected by global climate change. [ABSTRACT FROM AUTHOR]