Saline-alkali Land Research Articles

Growth, Photosynthesis, and Gene Expression of Bermudagrass in Response to Salinity and Shade Stress

Soil salinization is an environmental problem globally. Bermudagrass (Cynodon dactylon) has long been used for soil restoration in saline-alkali land. Urbanization and the compound planting pattern combining trees, bushes, and grasses induced shading are becoming one of the most significant environmental constraints on the management of bermudagrass, which directly affects photosynthetic characteristics. Salinity and shade have become the most important environmental constraints on lawn development and implementation. Previous studies have shown that the plant physiological response under combined stress was different from that under single stress. The purpose of this research was to investigate the effects of salinity stress, shade stress, and the combined stress on bermudagrass. Shade nets were used to simulate shade stress to 85% shade. The NaCl concentration gradient for salinity stress was 1.0% for 7 days, 1.5% for 7 days, and 2.0% for 13 days, respectively. The combined stress combines the two approaches mentioned previously. The results showed that the salinity stress significantly inhibited the plant height, leaf relative water content, chlorophyll content, the chlorophyll a fluorescence induction (OJIP) curve and other photosynthetic parameters of bermudagrass while increasing electrolyte leakage when compared with control. Shade stress significantly enhanced the plant height, chlorophyll content, electrolyte leakage, the OJIP curve, and other photosynthetic parameters. Under the combined stress, the plant height and relative water content did not change significantly, but the photosynthetic parameters such as chlorophyll content and the OJIP curve increased. Furthermore, under the combined stress, the photosynthesis-related genes were regulated. Salinity stress inhibited the photosynthetic ability of bermudagrass more than shade stress, while the combined stress exhibited a considerably better photosynthetic ability. These findings provide information for the usage of bermudagrass in salinized shade conditions.

Effects of nitrogen fertilizer application on saline-alkali land cotton in China quantified using meta-analysis and regression analysis

Effects of nitrogen fertilizer application on saline-alkali land cotton in China quantified using meta-analysis and regression analysis

Physiological and Biochemical Characteristics and Response Patterns of Salinity Stress Responsive Genes (SSRGs) in Wild Quinoa (Chenopodium quinoa L.)

Cultivating salt-tolerant crops is a feasible way to effectively utilize saline-alkali land and solve the problem of underutilization of saline soils. Quinoa, a protein-comprehensive cereal in the plant kingdom, is an exceptional crop in terms of salt stress tolerance level. It seems an excellent model for the exploration of salt-tolerance mechanisms and cultivation of salt-tolerant germplasms. In this study, the seeds and seedlings of the quinoa cultivar Shelly were treated with different concentrations of NaCl solution. The physiological, biochemical characteristics and agronomic traits were investigated, and the response patterns of three salt stress-responsive genes (SSRGs) in quinoa were determined by real-time PCR. The optimum level of stress tolerance of quinoa cultivar Shelly was found in the range of 250–350 mM concentration of NaCl. Salt stress significantly induced expression of superoxide dismutase (SOD), peroxidase (POD), and particularly betaine aldehyde dehydrogenase (BADH). BADH was discovered to be more sensitive to salt stress and played an important role in the salt stress tolerance of quinoa seedlings, particularly at high NaCl concentrations, as it displayed upregulation until 24 h under 100 mM salt treatment. Moreover, it showed upregulation until 12 h under 250 mM salt stress. Taken together, these results suggest that BADH played an essential role in the salt-tolerance mechanism of quinoa. Based on the expression level and prompt response induced by NaCl, we suggest that the BADH can be considered as a molecular marker for screening salt-tolerant quinoa germplasm at the early stages of crop development. Salt treatment at different plant ontogeny or at different concentrations had a significant impact on quinoa growth. Therefore, an appropriate treatment approach needs to be chosen rationally in the process of screening salt-tolerant quinoa germplasm, which is useful to the utilization of saline soils. Our study provides a fundamental information to deepen knowledge of the salt tolerance mechanism of quinoa for the development of salt-tolerant germplasm in crop breeding programs.

Characterization and bioactive component analysis of filamentous bacterium XJ-16

Actinomycetes, which can produce a variety of bioactive compounds in the metabolic process, is one of the important sources of novel drugs, enzymes, anti-tumor drugs and enzyme inhibitors. It has been the focus of researchers to find and develop Actinomycetes with special characters. Strain XJ-16 is a blue alkali-resistant filamentous bacterium with high antimicrobial activity isolated from saline-alkali land of Xinjiang. Based on the classification, the enzyme production, metabolite antibacterial activity, and antibacterial substance isolation of XJ-16 were explored. which showed that XJ-16 belongs to the blue group of Streptomyces sp, and it can secrete cellulase, lipase, urease, protease, catalase and oxidase during metabolism. In addition, the bacteriostatic substance secreted by the strain XJ-16 showed inhibitory effects against both Gram-positive and Gram-negative bacteria, as well as the yeast Candida albicans. Then it was found that the bacteriostasis produced by XJ-16 has strong tolerance to acid, weak tolerance to alkali, and easy to be inactivated. After tested by HPLC, the retention time of antimicrobial substance was 13.261 min. This study provides new research ideas and theoretical support for searching for new antibacterial compounds and further developing the blue alkaline Actinomycete XJ-16.

Constraints and Coordinated Allocation Strategies of Water and Land Resources for Sustainable Use of Coastal Saline-Alkali Land in the Yellow River Delta

Constraints and Coordinated Allocation Strategies of Water and Land Resources for Sustainable Use of Coastal Saline-Alkali Land in the Yellow River Delta

Analyzing the Process of Land-Use Transfer Flow in the Suhai Lake Basin in China, 1980–2018

The Suhai Lake Basin has held major ecological status as a crucial component of the Qinghai-Tibet Plateau’s ecological security barrier. The Suhai Lake Migratory Bird Nature Reserve’s safety and the livelihood of Kazakh citizens are now directly endangered by the frequent switching between land-use types and the decrease of ecosystem service functions caused by climate change and human activity. As a result, this work introduces the idea of land-use transfer flow. Through the application of interval level change and the land-use transfer chain, the process, affecting factors, and current issues of land-use change in the Suhai Lake Basin over the past 40 years are thoroughly investigated. The results showed that the intensity of land-use change was significant, at 0.055%, during the period 1990–2000, whereas the grassland area significantly increased, with a net increase of 23.07 km2, mainly from the conversion of saline-alkali land, swamp, and other unused land in the middle and lower reaches. The key factor influencing the growth of the grassland throughout this time has been the ecological management policy. As a result of the climate’s ongoing warming between 2000 and 2018, glacial meltwater and precipitation increased, the middle and lower ranges of the groundwater table rose, and the grassland degradation, swamp shrinkage, and soil salinization in the watershed all worsened. The degradation of grassland will result from both overgrazing and overprotection. Suhai Lake Wetland and Haizi Grassland Wetland are the most readily apparent examples of land-use changes in the Suhai Lake Basin from a spatial perspective. More consideration should be given to the ecological deterioration and land exposure in the glacier retreat zone of the upstream source region. The results can provide important information on the impact of regional development and the environmental governance policies of the changes in land use/cover in the Suhai Lake Basin.

Screening of Rhizosphere Microbes of Salt-Tolerant Plants and Developed Composite Materials of Biochar Micro-Coated Soil Beneficial Microorganisms

To develop composite materials of biochar micro-coated soil beneficial microorganisms, soil samples were collected from the saline-alkali land of the Penghu in Taiwan. After isolation, purification and identification, a total of one Bacillus amyloliquefaciens and two Bacillus megaterium were identified as the source of beneficial microorganisms. The agricultural waste is collected and initially crushed, and then made into biochar through a series of thermal cracking processes. The specific surface area of biochar is more than 100 m2/g, the fixed carbon is more than 80%, the proportion of medium and large pores is more than 30%, the pH after adjustment is 7.3 ± 0.2, and the pore size of beneficial microorganisms grows inward, which is one of the beneficial microorganisms. The biochar micro-coated soil-beneficial microorganism composite material developed in this experiment can indeed help crops to overcome the stress of salt damage to a certain extent, and Bacillus amyloliquefaciens can indeed promote plant growth and help crops effects of over-salting adversity.

Biochar and Nitrification Inhibitor (Dicyandiamide) Combination Had a Double-Win Effect on Saline-Alkali Soil Improvement and Soybean Production in the Yellow River Delta, China

Salt stress and nutrient deficiency strongly limited the productivity of coastal saline-alkali land in the Yellow River Delta. Biochar has been widely used to improve soil health and promote crop yield, and the positive effects of nitrification inhibitors on fertilizer use efficiency, especially nitrogen, were also verified. However, there were few types of research on the combined application of biochar and nitrification inhibitor dicyandiamide (DCD) on saline-alkali soil of the Yellow River Delta, China. In this study, five treatments, including no nitrogen (CK), normal NPK (N), NPK + 1%biochar (B), NPK + 2%DCD (D), and NPK + 1%biochar + 2%DCD (BD) were set to investigate the single and combined effect of biochar and DCD on nitrogen transform, soil properties, bacterial community structure, and soybean production. Results showed that BD application inhibited nitrification and increased the soil’s nitrate supply at the flowering stage, which reduced nitrogen waste and met the nitrogen demand for soybean growth. Biochar addition increased the soil’s pH and decreased the soil’s electrical conductivities and accelerated the soil’s macroaggregates formation, with the soil’s average mass diameter and geometric average diameter increasing by 78.69% and 30% in B, and 71.29% and 29.34% in BD relative to CK. Positive effects of inhibitors on soybean production were found in increasing soybean yield, hundred-grain weight, aboveground biomass, etc. Proteobacteria was the dominant phylum in the bacterial communities detected, and bacterial community diversity was significantly explained by nitrate content and soil aggregates (p < 0.05). Soil pH and DCD addition mainly influenced the abundance of the bacterial community, especially Actinobacteria. Biochar with DCD could be a feasible fertilization scheme for the coastal saline-alkali land in the Yellow River Delta, China.

Rapid saline-alkali sensitivity testing using hydrogel/gold nanoparticles-modified screen-printed electrodes

Rapid screening of microorganisms with good saline-alkali tolerance is of great significance for the improvement of saline-alkali land. In this study, a novel electrochemical method was developed for the rapid screening of saline-alkali-tolerant bacteria using a hydrogel/gold nanoparticles-modified screen-printed electrode. Monitoring bacterial growth using electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) yielded a new method to measure saline-alkali sensitivity. The strains were deposited on agarose hydrogel-AuNPs composite-modified electrodes with saline-alkali treatment control at a concentration of 50 mM. The electrochemical-derived growth curve of each bacterial strain was established to monitor the effect of saline-alkaline conditions on bacterial growth. The results showed that E. coli could grow on the hydrogel-AuNPs composite-modified electrodes without saline and alkali, while the growth of E. coli was inhibited after adding saline and alkali to the modified electrodes. In contrast, Paenibacillus lautus (HC_A) and Lysinibacillus fusiformis (HC_B) were able to grow on electrodes containing saline-alkali hydrogel-AuNPs composite modification. This fast growth curves of the strains derived from electrochemical analysis indicate that the possible time for salinity sensitivity results is <45 min. Compared to the traditional bacterial culture method lasting at least 1–2 days, this method has the clear advantages of rapidity, high efficiency, and low cost.

The Breeding of High-Quality Dandelions by NaCl Induced Callus Variation Combined with a Drosophila Tumor Cell Migration Test

Creating high-quality and salt-tolerant plant germplasm is an effective strategy to improve the utilization of saline-alkali land. Salt-induced callus mutation was used to create dandelion germplasm and mutant dandelion calluses were obtained under NaCl concentrations of 0.8%, 1%, and 1.2% with the identification of random amplified polymorphic DNA (RAPD) markers. A new dandelion line, “Binpu 2”, selected from the progenies of dandelion tissue culture plantlets that originated from callus treated under 0.8% NaCl, was evaluated in light of its morphological characteristics, bioactive components, and antitumor functions. Results showed that the plant shape of “Binpu 2”was nearly upright; its cichoric acid content was 6.7 mg/g, which was 39.6% and 36.7% higher than its mother plant and local dandelion cultivar, respectively; its leaf water extracts of 0.2 g/mL had a significant inhibitory effect on cell polarity disruption-induced cell migration without affecting drosophila normal growth, revealed by the strong inhibitory effect on tumor cell migration, the increased level of MMP1 and β-Integrin, and the reduced E-cadherin expression. Our results suggested that “Binpu 2” originated from salt-induced mutant performed better than its mother plant and processed strong antitumor function, which was suitable for amplified cultivation in saline-alkali land for food and medicinal industrial development.

Nitrogen Promotes the Salt-Gathering Capacity of Suaeda salsa and Alleviates Nutrient Competition in the Intercropping of Suaeda salsa/Zea mays L.

Nitrogen accelerates salt accumulation in the root zone of an euhalophyte, which might be beneficial for inhibiting the salt damage and interspecific competition for nutrients of non-halophytes in intercropping. However, the variations in the effect of euhalophyte/non-halophyte intercropping with nitrogen supply are poorly understood. Here, we selected the euhalophyte Suaeda salsa (suaeda) and non-halophyte Zea mays L. (maize) as the research objects, setting up three cropping patterns in order to explore the influence of nitrogen application on the intercropping effect in the suaeda/maize intercropping. The results showed that the biomass of maize in the intercropping was significantly lower than that in the monoculture, while for suaeda, it was higher in the intercropping than that in the monoculture. The biomass of maize under NO3--N treatment performed significantly higher than that under no nitrogen treatment. Moreover, under suitable NO3--N treatment, more salt ions (Na+, K+) gathered around the roots of suaeda, which weakened the salt damage on maize growth. In the intercropping, the effect of NO3--N on the maize growth was enhanced when compared with the non-significant effect of NH4+-N, but a positive effect of NH4+-N on suaeda growth was found. Therefore, the disadvantage of maize growth in the intercropping suaeda/maize might be caused by interspecific competition to a certain extent, providing an effective means for the improvement of saline-alkali land by phytoremediation.

Multi-objective optimization of winter irrigation for cotton fields in salinized freeze-thaw areas

The adaptive management of saline-alkali land and water resources can effectively alleviate land degradation and water depletion, and appropriate irrigation can improve crop yield and production efficiency. Based on the soil changes and comprehensive crop benefits under different initial soil environments, the optimization of the irrigation amount of cotton in saline-alkali areas is of great significance for the improvement of agricultural production of these areas in developing countries and even worldwide. The responses of farmland with various degree of salinization to different winter irrigation amounts in seasonal freeze-thaw arid areas should therefore be further explored. In this study, the soil moisture-temperature-salinity changes and the crop growth responses of three cotton fields with different salinization levels (5.15, 8.17, and 11.15 g·kg-1) under four winter irrigation amounts (0, 3000, 3600, and 4200 m3·ha-1) were intensively investigated via a two-year field experiment in Xinjiang Province, China. The results demonstrate that winter irrigation significantly improved the soil moisture-temperature-salinity environment during the freeze-thaw period, and the influence was affected by the field salinization level. The initial salinity of salinized field promoted soil thawing and water storage, and inhibited soil freezing and salt leaching. The intraspecific relationship of salinized cotton fields changed from competition to promotion under winter irrigation, and soil salinity weakened the optimization of the intraspecific relationship. The multiple correlations between the benefit indexes of cotton were significantly strengthened under winter irrigation, and the negative effect of the soil salinization level on the cotton benefit indexes was stronger than that of the winter irrigation amount. Based on a multiple regression analysis, the optimal winter irrigation amounts for cotton fields with mild, moderate, and severe salinization were found to be 3416.83–4256.14, 4256.14–6502.96, and 6502.96–9614.24 m3·ha-1, respectively. This research provides a theoretical basis for determining the appropriate winter irrigation amount for cotton fields with various degrees of salinization in seasonal freeze-thaw arid regions.

Nitratireductor luteus sp. nov. isolated from saline-alkali land.

The Gram-staining negative, oxidase and catalase negative strain KC-ST17T, isolated from saline-alkali land, was characterized using a polyphasic approach to determine its taxonomic position. Using 16S rRNA gene sequence analysis, the highest similarity of strain KC-ST17T was found with Nitratireductor pacificus CCTCC AB 209302T (97.2%). Cells are aerobic, non-motile, and rod-shaped. The isolate was found to be able to grow in NaCl concentrations of 0-4.0%. The assembled genome of strain KC-ST17T had a total length of 4.9Mb with a G + C content of 62.7%. According to genome analysis, strain KC-ST17T encodes genes involved in the reduction of nitrate to nitrite, which may play a role in the utilization of nitrogenous compounds from the soil as an immediate source of energy. Based on the phenotypic characteristics and phylogenetic analysis, strain KC-ST17T was confirmed to represent a novel species in the Nitratireductor genus; thus, the name Nitratireductor luteus sp. nov. was proposed. The type strain of this species was KC-ST17T (= KCTC 92119T = MCCC 1K07309T).

H2S Enhanced the Tolerance of Malus hupehensis to Alkaline Salt Stress through the Expression of Genes Related to Sulfur-Containing Compounds and the Cell Wall in Roots.

Malus is an economically important plant that is widely cultivated worldwide, but it often encounters saline-alkali stress. The composition of saline-alkali land is a variety of salt and alkali mixed with the formation of alkaline salt. Hydrogen sulfide (H2S) has been reported to have positive effects on plant responses to abiotic stresses. Our previous study showed that H2S pretreatment alleviated the damage caused by alkaline salt stress to Malus hupehensis Rehd. var. pingyiensis Jiang (Pingyi Tiancha, PYTC) roots by regulating Na+/K+ homeostasis and oxidative stress. In this study, transcriptome analysis was used to investigate the overall mechanism through which H2S alleviates alkaline salt stress in PYTC roots. Simultaneously, differentially expressed genes (DEGs) were explored. Transcriptional profiling of the Control-H2S, Control-AS, Control-H2S + AS, and AS-H2S + AS comparison groups identified 1618, 18,652, 16,575, and 4314 DEGs, respectively. Further analysis revealed that H2S could alleviate alkaline salt stress by increasing the energy maintenance capacity and cell wall integrity of M. hupehensis roots and by enhancing the capacity for reactive oxygen species (ROS) metabolism because more upregulated genes involved in ROS metabolism and sulfur-containing compounds were identified in M. hupehensis roots after H2S pretreatment. qRT-PCR analysis of H2S-induced and alkaline salt-response genes showed that these genes were consistent with the RNA-seq analysis results, which indicated that H2S alleviation of alkaline salt stress involves the genes of the cell wall and sulfur-containing compounds in PYTC roots.

Improved effects of combined application of nitrogen-fixing bacteria Azotobacter beijerinckii and microalgae Chlorella pyrenoidosa on wheat growth and saline-alkali soil quality

Soil salinization seriously affects crop yield and soil productivity. The application of bacteria and microalgae has been considered as a promising strategy to alleviate soil salinization. However, the effect of bacteria-microalgae symbiosis on saline-alkali land is still unclear. This study evaluated the effects of Azotobacter beijerinckii, Chlorella pyrenoidosa, and their combined application on the wheat growth and saline-alkali soil improvement. The results showed that, among all the treatments, A. beijerinckii + live C. pyrenoidosa combined inoculation group (BA) had the best effect on increasing wheat plant biomass, improving salt tolerance, and improving soil fertility. The dry weight of wheat plant in the BA group increased by 66.7%, 17.4%, and 35.0%, respectively, compared with the control group (CK), A. beijerinckii inoculation group (B), and live C. pyrenoidosa inoculation group (A). The total nitrogen content of wheat plant in the BA group increased by 69.5%, 76.7%, and 71.1%, compared with the CK, B, and A group. The proline content of wheat plant in the BA group was 100% higher than that in the CK group. The N/P ratio and K/Na ratio of wheat plant increased by 157% and 12.9% in the BA group compared with the CK group, respectively, which was more conducive to alleviating nitrogen limitation and salt stress. The A. beijerinckii + live C. pyrenoidosa inoculation treatment better reduced soil pH and improved the availability of phosphorus in soil. This study illustrated the comprehensive application prospects of bacteria-microalgae interactions on wheat growth promotion and soil improvement in saline-alkali land, and provided a new effective strategy for improving saline-alkali soil quality and increasing crop productivity.

Advances and future research in ecological stoichiometry under saline-alkali stress.

Saline-alkali stress is a serious abiotic factor which negatively impacts agricultural production and the ecological environment. Thus, improving the development of saline-alkali soil and reducing the effects of saline-alkali stress is a key issue for sustainable agricultural development and environmental protection. As such, it is unsurprising that researchers have lately focused on how to improve saline-alkali soil, increase the agricultural yield of saline-alkali land, and promote the adaptive growth of plants in saline-alkali soil. This paper reviews the latest research concerning nutrient content changes in saline-alkali soil, along with the associated changes in key nutrients in plants, to summarize which methods are most effective for improving the plant growth under saline-alkali stress. Finally, the prospects for alleviating saline-alkali stress and improving saline-alkali soil are put forward as a theoretical foundation for the stabilization of plant growth in saline-alkali soil, expansion of arable land area, crop yield improvement, and effective environmental protection.

Meta-Analysis of the Effect of Saline-Alkali Land Improvement and Utilization on Soil Organic Carbon.

There is a large amount of saline-alkali land in China. Through the improvement and utilization of saline-alkali land to improve the carbon content in soil, it can not only become a reserve resource of cultivated land or grazing grassland, but also become an important land "carbon sink". In this study, we performed a comprehensive meta-analysis to identify the impact of improvement and utilization of saline-alkali soil on soil organic carbon (SOC) in China. Our results showed that the soil salt and alkali content in Heilongjiang Province and Jilin Province in China was the highest, with an SOC content between 3.05 and 17.8 g/kg and pH between 8.84 and 9.94. Among the five methods of reclamation, halophyte planting, fertilization, biochar and modifier application, only biochar and modifier application significantly increased the SOC content (p &lt; 0.05). The content of SOC in saline-alkali soil was 2.9-6.3 g/kg before biochar application, and significantly increased to 6.2-13.05 g/kg after biochar application (p &lt; 0.01). The SOC content was 3.05-8.12 g/kg before the application of the modifier, and significantly increased to 3.68-9 g/kg (p &lt; 0.05) after the application of the modifier. After utilization and improvement of saline-alkali land, the total nitrogen, available phosphorus and available potassium also increased significantly (p &lt; 0.05). This study provides a scientific basis for further understanding the improvement and utilization of saline-alkali land in China and its potential for increasing carbon sinks.

Dynamics of Spatiotemporal Variation of Groundwater Arsenic Due to Salt-Leaching Irrigation and Saline-Alkali Land

Determining the link between the evolution of salt-leaching irrigation, saline-alkali land, and groundwater arsenic (As) is essential to prevent groundwater arsenic pollution and implement appropriate soil salinization control projects. The objectives of our study were to explore the spatiotemporal correlation of saline-alkali land and salt-leaching irrigation with groundwater As in the Hetao Plain. Therefore, groundwater As concentrations during Period I (2006–2010) and Period II (2016–2020) were collected by historical data and chemical measurements. Salt-leaching irrigation area and saline-alkali land area in Period I and Period II were extracted through remote sensing data. With the increase of the salt-leaching irrigation area level (SLIAL) and saline-alkali land area level (SALAL), the variation trend in groundwater As concentration slightly fluctuated, with an increase in the SLIAL at the low SALAL, which may be because short-term flooding may not considerably enhance As mobilization. Lower groundwater As concentrations appeared in regions with higher SLIAL and lower SALAL. A larger saline-alkali land area (higher SALAL) increased the groundwater As concentration. The path analysis model confirmed that salt-leaching irrigation may increase groundwater salinity to affect groundwater As levels and to decrease the saline-alkali land area. From Periods I to II, the difference in path analysis results may imply that the decrease in the saline-alkali land area may have influenced As mobilization due to competitive adsorption caused by the increase in total dissolved solids (TDS) in groundwater. Our results provide new insights for the impacts of saline-alkali land and salt-leaching irrigation both on groundwater As concentration and the geochemical processes of As enrichment in arid and semi-arid areas with more serious salinization.

PsnWRKY70 Negatively Regulates NaHCO3 Tolerance in Populus.

Poplar is an important afforestation and ornamental tree species in Northeast China. The distribution area of saline-alkali land is approximately 765 hm2 in Northeast China. The breeding of saline-alkali-resistant transgenic trees could be an effective method of afforestation in saline-alkali land. WRKY transcription factors play a crucial role in abiotic stress. In this study, we analyzed the genetic stability of the two-year-old PsnWRKY70 transgenic poplars. The results showed that PsnWRKY70 of transgenic poplars had been expressed stably and normally at the mRNA level. The gene interference expression (RE) lines had no significant effect on the growth of PsnWRKY70 under NaHCO3 stress, and the alkali damage index of RE lines was significantly lower than that of WT and overexpression (OE) lines at day 15 under NaHCO3 stress. POD activity was significantly higher in RE lines than in WT. The MDA content of the RE line was lower than that of the WT line. Transcriptome analysis showed that RE lines up-regulated genes enriched in cell wall organization or biogenesis pathway-related genes such as EXPA8, EXPA4, EXPA3, EXPA1, EXPB3, EXP10, PME53, PME34, PME36, XTH9, XTH6, XTH23, CESA1, CESA3, CES9; FLA11, FLA16 and FLA7 genes. These genes play an important role in NaHCO3 stress. Our study showed that the interference expression of the PsnWRKY70 gene can enhance the tolerance of NaHCO3 in poplar.

Research on Ecological Restoration Technology in Arid or Semi-Arid Areas from the Perspective of the Belt and Road Initiative

In the new era of the rapid development of economic globalization and the community of human destiny, the implementation of the “One Belt and One Road” (OBOR) construction model is designed to coordinate environmental protection and economic development. Most of the countries along the Silk Road in the 21st century are developing countries, and the majority of them are facing the same ecological and developmental difficulties as China. In this paper, under the background of the “OBOR” strategy and on the basis of the distribution of global climate types, we selected Central Asia and Northwest China, which have temperate continental climates, as the research objects. We sorted out and summarized the main ecological problems faced by Western China and Central Asia during the development of the “Belt and Road” initiative. At the same time, in combination with the major ecological governance projects implemented in recent years, we proposed key ecological governance technologies that have a certain degree of scalability, such as key technologies for water resource utilization and protection, sand prevention and control, and saline-alkali land governance. The aim was to offer the experiences and a reference for providing technological models for the “one belt along the road” region and the country to build an effective ecological governance system. Two suggestions are then proposed for improving the feasibility and rationality of ecological governance technology in the construction of the “One Belt, One Road”. 1) With the implementation of the strategy of “OBOR” construction, the ecological threats the OBOR countries are facing cannot be ignored. Every country needs to jointly act to build an “OBOR” ecological civilization. 2) The participants must pay attention to the spatial heterogeneity and temporal dynamics of ecological carrying capacity, and provide data reference and support for the reasonable allocation of ecological governance technology.