Salt-tolerant Genotypes Research Articles

Investigating the genetic basis of salt-tolerance in common bean: a genome-wide association study at the early vegetative stage

Salinity poses a significant challenge to global crop productivity, affecting approximately 20% of cultivated and 33% of irrigated farmland, and this issue is on the rise. Negative impact of salinity on plant development and metabolism leads to physiological and morphological alterations mainly due to high ion concentration in tissues and the reduced water and nutrients uptake. Common bean (Phaseolus vulgaris L.), a staple food crop accounting for a substantial portion of consumed grain legumes worldwide, is highly susceptible to salt stress resulting in noticeable reduction in dry matter gain in roots and shoots even at low salt concentrations. In this study we screened a common bean panel of diversity encompassing 192 homozygous genotypes for salt tolerance at seedling stage. Phenotypic data were leveraged to identify genomic regions involved in salt stress tolerance in the species through GWAS. We detected seven significant associations between shoot dry weight and SNP markers. The candidate genes, in linkage with the regions associated to salt tolerance or harbouring the detected SNP, showed strong homology with genes known to be involved in salt tolerance in Arabidopsis. Our findings provide valuable insights onto the genetic control of salt tolerance in common bean and represent a first contribution to address the challenge of salinity-induced yield losses in this species and poses the ground to eventually breed salt tolerant common bean varieties.

A comprehensive approach for evaluating salinity stress tolerance in brinjal (Solanum melongena L.) germplasm using membership function value.

Salinity is a major stress factor affecting plant growth and development, which limits the productivity of vegetable crops. Brinjal (Solanum melongena L.), an important vegetable cultivated across the globe is susceptible to salinity stress. In the present study, the salinity tolerance response of 110 brinjal germplasm lines was evaluated at the germination stage using the membership function value (MFV). The MFV is a comprehensive index that integrates salt-tolerance indices of germination parameters. The brinjal germplasms were classified into highly salt-tolerant (>0.79), salt-tolerant (0.79-0.65), moderately salt-tolerant (0.64-0.21), salt-sensitive (0.20-0.07), and highly salt-sensitive (<0.07) based on their mean MFV. Among all the traits examined, germination percentage (0.874) and vigour index-I (0.808) were the most reliable traits for assessing salinity tolerance, showing a higher correlation with mean MFV. Furthermore, a comprehensive mathematical model was developed for evaluating the salt-tolerance of the brinjal germplasm. We validated our model by evaluating the brinjal germplasm at the seedling stage through a hydroponic experiment, and a strong positive correlation was observed between growth parameters at the germination and seedling stages. Salt-tolerant genotypes showed higher chlorophyll content, photosynthetic performance and biomass accumulation with lower canopy temperature (1.57°C) under salinity compared to susceptible genotypes (2.62°C). These findings provide valuable insights into the salinity tolerance of the brinjal germplasm, and identified potential candidates to elucidate the molecular mechanisms and develop salinity-tolerant cultivars. To our knowledge, this is the first report using a mathematical model based on MFV to evaluate the salt-tolerance of any vegetable crop.

Systematic assessment of salt tolerance based on morpho-physiological traits and genes related in inbred rice lines at the seedling stage

Abstract. Herawati R, Simarmata M, Masdar, Purwoko BS, Miswati. 2023. Systematic assessment of salt tolerance based on morpho-physiological traits and genes related in inbred rice lines at the seedling stage. Biodiversitas 24: 6256-6267. Salinity stress is an abiotic constraint that limits rice productivity. Salinity-tolerant traits are very complex and involve many genes. Therefore, it is difficult to conclude how rice plants respond to salinity stress. This study aimed to investigate the genetic potential of 19 rice genotypes for salt tolerance as well as the quantitative impacts of varying salinity stress levels on a subset of the genotypes. Salinity tolerance is identified in two stages: assessing salinity stress in nutrient solutions using 0, 5,000 (EC 7.8 dS.m-1), and 10,000 ppm (EC 15.62 dS.m-1). Gene expression analysis detected genes controlling salinity stress tolerance using two pairs of specific primers: DST (Drought Salt Tolerance) and OsAPX (ascorbate peroxidase). The results showed that all lines could survive high salinity stress up to EC 7.8 dS.m-1. Biplot is reflected in K-means grouping the 21 rice genotypes into three major groups, namely salt-sensitive (1 genotype, 4.75%), moderately salt-tolerant (2 genotypes, 9.5%), and salt-tolerant-very tolerant (18 genotypes, 85.7%). The DST and OsAPX1 genes showed both genes were expressed under salinity stress, although some lines showed smears or even did not appear at all, namely in G3 and G7. This result is consistent with the PCA analysis, where genotypes G3 and G7 are categorized as moderately tolerant. This study reveals that screening at the seedling stage combined with marker-assisted selection can identify tolerant genotypes. Furthermore, conducting field trials on soil salinity with EC &gt; 4 dS.m-1 is recommended to obtain salinity-tolerant lines as potential new varieties.

The potential application of biochar and salicylic acid to alleviate salt stress in soybean (Glycine max L.)

Salt stress has been one of the major contributor which affect soybean seed germination, its establishment, growth, and physiology stages. Utilization of strategies such as soil amendment and elicitors are of significant importance to reduce the disadvantageous effects of salt stress. In this regard, the objectives of the present study were to evaluate the effect of biochar and salicylic acid on morphological and physiological properties of soybean subjected to salinity. The first experiment was carried out based on completely randomized design with three replications including 11 soybean cultivars such as Williams, Saba, Kowsar, Tapor, Sari, Telar, Caspian, Nekador, Amir, Katol and Sahar and various levels of salinity such as 0, 2, 4, 6 dS/m of NaCl. The second experiment was performed as factorial design in a randomized complete block design with three replications consisting of treatments of biochar (0, 5 and 10 WP), salicylic acid (0, 0.5 and 1 mM), and NaCl (0, 2.5, 5, 7.5 dS/m). With respect to seed germination result, various concentrations of salt stress showed negative impact not only on all studied traits, but also varied among soybean cultivars indicating Amir cultivar as the best salt tolerant soybean genotype among others. In addition, our data exhibited that the interaction effect of biochar and salicylic acid on salt treated soybean plant were positively significant on some morphological traits such as leaf area, shoot dry/fresh weight, total dry/fresh weight and physiological attributes including chlorophyll a, flavonoid, proline contents, catalase and peroxidase activities. Moreover, the resultant data showed that the combination treatment of 5 and 10 WP of biochar and 1 mM of salicylic acid caused increase of the aforementioned parameters in order to improve their performance subjected to higher concentration of salinity. In final, it was concluded that the coupled application of biochar alongside salicylic acid was recommended as proficient strategy to mitigate the injurious influences of salt stress in soybean or other probable crops.

Comparison of expression patterns of salt tolerance-related gene HKT1;4 in bread wheat genotypes

The HKT gene family, which encodes K+ /Na+ transport proteins of cell membranes, plays a unique role in controlling plant responses to salt stress. The transcriptional activity of the HKT1;4 gene was assessed in root and leaf tissues of bread wheat genotypes (tolerant Murov 2 and sensitive Aran) that differed in salt tolerance. The HKT1;4 transcript was not found in plant leaves. A genotype-specific change in the root-specific expression of the HKT1;4 gene was observed in response to salt stress: expression of a given gene was weakened in the salt-tolerant genotype and increased in the sensitive genotype. The data could be used to improve the salt tolerance of the wheat plant. Keywords: Wheat, salinity tolerance, TaHKT1;4 gene

Comparative Transcript Profiling and Multiplex qRT-PCR Analysis Between Salt-Tolerant and Sensitive Wheat Genotypes

Identification of candidate genes combined with gene expression profiling carries importance to facilitate the molecular basis of salt stress response in plants. Here, cDNA-AFLP was used to compare the transcribed sequences among two bread and two durum wheat genotypes with different levels of salt tolerance. Transcript derived fragments (TDFs) screened on polyacrylamide gels and 36 salt stress induced unique fragments were detected in salt tolerant bread wheat genotype (Alpu cv.). The fragment size of these 36 TDFs was ranged between 99bp to 252bp. Full sequence information of 14 TDFs were obtained after cloning, then GeXP analyzer-based multiplex qRT-PCR assay was performed on leaf tissue derived from 12 TDFs. Targeted gene expression levels of two TDFs (TDF4-GT066302 and TDF11-GT066301) were showed clear upregulation in salt tolerant bread wheat genotype (Alpu cv.) and they were matched with hypothetical proteins. Especially, gene expression level of GT066301 was increased as 3.28 fold at 27th hours of salt stress for salt tolerant genotype. According to blastx similarity results, out of 14 sequenced fragments, two TDFs were closely matched with “cytochrome P450 monooxygenase” protein while four of them matched with Oryza “hypothetical” and “unknown” proteins. Outputs of this study might ensure comparative data for hypothetical protein gene expression and new useful alleles in response to salt stress in wheat.

Response of nine triticale genotypes to different salt concentrations at the germination and early seedling stages.

Salinity stress poses a major challenge to agricultural productivity worldwide, and understanding their responses at the early growth stage is vital for devising strategies to cope with this stress. Therefore, to improve triticale productivity, this study investigated the salinity stress tolerance of different salt-tolerant triticale genotypes aiming to cultivate them on saline soils. To this end, salinity stress impacts on nine triticale genotypes, i.e., Zhongsi 1084, Gannong No. 2, Gannong No. 4, Shida No. 1, C6, C16, C23, C25 and C36 at germination and early seedling stages was evaluated. Each genotype was subjected to six treatments inducing control, 40, 80, 120, 160, and 200 mM NaCl treatments to study their effect on seedling and termination traits of the nine genotypes. Compared to the overall mean seedling vigor index, the seedling vigor index was higher in the genotypes Zhongsi 1084 and C6 (39% and 18.1%, respectively) and lower in Gannong No.2 (41%). Increasing NaCl concentrations negatively affected germination and seedling traits. Compared to other genotypes, Zhongsi 1084 had the highest mean germination rate, germination vigor index, germination percentage, mean daily germination and germination energy. It also showed the lowest relative salt injury. The relative salt injury was higher in the genotype Shida No. 1 than those in Gannong No. 2, Gannong No. 4, Shida No. 1, C16, and C36 genotypes. All genotypes exhibited desirable mean germination time except for line C6. High significant positive correlations were observed among germination rate, germination vigor index, germination percentage, mean daily germination, seedling vigor index, and root length. Principal component analysis (PCA) grouped the most desirable genotypes into two clusters. Our study determined salt stress tolerance of nine triticale genotypes at germination and early seedling stages. to select salt-tolerant genotypes that can be cultivated on saline soil or after salt irrigation.

Transcriptome analysis and physiological changes in the leaves of two Bromus inermis L. genotypes in response to salt stress.

Soil salinity is a major factor threatening the production of crops around the world. Smooth bromegrass (Bromus inermis L.) is a high-quality grass in northern and northwestern China. Currently, selecting and utilizing salt-tolerant genotypes is an important way to mitigate the detrimental effects of salinity on crop productivity. In our research, salt-tolerant and salt-sensitive varieties were selected from 57 accessions based on a comprehensive evaluation of 22 relevant indexes, and their salt-tolerance physiological and molecular mechanisms were further analyzed. Results showed significant differences in salt tolerance between 57 genotypes, with Q25 and Q46 considered to be the most salt-tolerant and salt-sensitive accessions, respectively, compared to other varieties. Under saline conditions, the salt-tolerant genotype Q25 not only maintained significantly higher photosynthetic performance, leaf relative water content (RWC), and proline content but also exhibited obviously lower relative conductivity and malondialdehyde (MDA) content than the salt-sensitive Q46 (p < 0.05). The transcriptome sequencing indicated 15,128 differentially expressed genes (DEGs) in Q46, of which 7,885 were upregulated and 7,243 downregulated, and 12,658 DEGs in Q25, of which 6,059 were upregulated and 6,599 downregulated. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the salt response differences between Q25 and Q46 were attributed to the variable expression of genes associated with plant hormone signal transduction and MAPK signaling pathways. Furthermore, a large number of candidate genes, related to salt tolerance, were detected, which involved transcription factors (zinc finger proteins) and accumulation of compatible osmolytes (glutathione S-transferases and pyrroline-5-carboxylate reductases), etc. This study offers an important view of the physiological and molecular regulatory mechanisms of salt tolerance in two smooth bromegrass genotypes and lays the foundation for further identification of key genes linked to salt tolerance.

Improving the genetic potential of okra (Abelmoschus esculentus L.) germplasm to tolerate salinity stress

Okra (Abelmoschus esculentus L.) is the most consumed vegetable worldwide with the potential for diverse ecological adaptation. However, increasing salinization and changing climatic conditions are posing serious threats to the growth, yield, and quality of okra. Therefore, to mitigate increasing soil salinization and ensure sustainable okra production under rapidly changing climatic conditions, evaluation of new okra germplasm to develop salt tolerant cultivars is direly needed. The present study was designed to evaluate the genetic resources of okra genotypes for salt tolerance at growth and reproductive phases. Based on mophological and physio-biochemical responses of plants under stress condition, genotypes were divided into salt tolerant and succeptible groups. The experiment was comprised of 100 okra genotypes and each genotype was grown under control conditions and 6.5 dS m−1 NaCl concentration in a pot having 10 kg capacity. The experiment was conducted in a completely randomized design and each treatment was replicated three times. The results showed vast genetic variability among the evaluated okra germplasm traits like days to emergence, pod length, pod diameter, plant height, stem girth, and other yield-related parameters. Correlation analysis showed a highly significant positive association among the number of leaves at first flower and plant height at first flower.Likewise, pod weight also revealed a highly significant positive relationship for pod weight plant-1, pod length, and K+: Na+. Principal Component Analysis (PCA) revealed that out of 16 principal components (PCs), five components showed more than one eigenvalue and the first six PCs contributed 67.2% of the variation. Bi-plot analysis illustrated that genotypes 95, 111, 133, 99, and 128, under salt stress conditions, exhibited both high yield per plant and salt-tolerant behavior in other yield-related traits. On the basis of all studied traits, a salt susceptible group and a salt-tolerant group were formed. The salt tolerant group comprised of 97, 68, 95, 114, 64, 99, 111, 133, 128, and 109 genotypes, whereas, the salt susceptible group contained 137, 139, 130, 94, and 125 genotypes. Salt-tolerant okra genotypes were suggested to be used in further breeding programs aimed to develop salt tolerance in okra. These insights will empower precision breeding, underscore the importance of genetic diversity, and bear the potential to address the challenges of salt-affected soils while promoting broader agricultural resilience, economic prosperity, and food security.

One size does not fit all: Different strategies employed by triticale and barley plants to deal with soil salinity

Salinity stress tolerance is a polygenic trait conferred by multiple physiological mechanisms, operating at various levels of plant structural organization. In this work, we have compared adaptative strategies employed by barley and triticale, two most tolerant cereal species, to deal with saline conditions. While the photosynthetic attributes were considerably reduced by 200 mM NaCl treatment in both species, triticale plants maintained higher photosynthetic capacity per unit leaf area compared with barley. Triticale plants also showed higher stomatal conductance under both saline and non-saline conditions, explaining the above photosynthetic rate. However, this high photosynthetic capacity in triticale was not translated into higher biomass (as compared with barley) due to stronger salinity-induced inhibition of tillering in the former species. Leaf elemental analysis revealed that salinity tolerance in triticale was related to its ability to exclude Na+ from the shoot while tolerant barley plant tended to accumulate more Na in shoot upon exposure to salt stress, for osmotic adjustment purposes. Salinity tolerance in both species was also causally associated with higher Fe content that was essential for activation of superoxide dismutase (SOD) to reduce the extent of oxidative stress. Electrophysiological experiments also revealed several patterns associated with control of ion transport in root epidermis, of which desensitization of K+- and Ca2+- ROS-inducible cation channels were the main trait conferring salinity tolerance. Cytosolic K+ retention in the root elongation zone in response to salt stress was more efficient in both triticale genotypes compared to barley. Finally, barley and salt tolerant genotypes of triticale showed higher speed of stomata, thus possessing higher water use efficiency.

Comparative Transcriptome Analysis Reveals the Underlying Response Mechanism to Salt Stress in Maize Seedling Roots.

Crop growth and development can be impeded by salt stress, leading to a significant decline in crop yield and quality. This investigation performed a comparative analysis of the physiological responses of two maize inbred lines, namely L318 (CML115) and L323 (GEMS58), under salt-stress conditions. The results elucidated that CML115 exhibited higher salt tolerance compared with GEMS58. Transcriptome analysis of the root system revealed that DEGs shared by the two inbred lines were significantly enriched in the MAPK signaling pathway-plant and plant hormone signal transduction, which wield an instrumental role in orchestrating the maize response to salt-induced stress. Furthermore, the DEGs' exclusivity to salt-tolerant genotypes was associated with sugar metabolism pathways, and these unique DEGs may account for the disparities in salt tolerance between the two genotypes. Meanwhile, we investigated the dynamic global transcriptome in the root systems of seedlings at five time points after salt treatment and compared transcriptome data from different genotypes to examine the similarities and differences in salt tolerance mechanisms of different germplasms.

Integrating Agro-Morpho-Physiological Traits and SSR Markers for Detecting the Salt Tolerance of Advanced Spring Wheat Lines under Field Conditions

To successfully enhance the salt tolerance of genotypes, it is crucial to conduct field-based trials, establish effective screening criteria and analysis tools, evaluate salt tolerance at various growth stages, and integrate phenotypic assessment-based traits with molecular markers. This study aimed to assess the salt tolerance of 16 F8 recombinant inbred lines (RILs) and eight genotypes by analyzing 13 agro-morpho-physiological traits using various analysis tools and SSR markers under both control and high salinity levels (15 dS m−1) in real field conditions. Analysis of variance (ANOVA), comparison of mean values, calculation of reduction percentage, and multivariate analysis were used to compare the assessed traits among genotypes and identify which traits are the most effective ones in describing the salt tolerance of these genotypes. A heatmap cluster analysis (HMCA) was also employed to categorize the salt tolerance of genotypes into different clusters based on the stress tolerance index (STI) for all traits. The ANOVA results revealed significant statistical differences (p ≤ 0.05) between the genotypes and salinity levels for all assessed traits in each season and their combined data. Moreover, the 150 mM NaCl treatment led to decreases in the assessed traits by 10.2% to 36.9% when compared to the control treatments. Furthermore, the mean values of assessed traits for certain genotypes were approximately one to three times greater than those of other genotypes. Principal component analysis has identified plant dry weight, green leaf area, leaf area index, and grain yield per hectare as effective screening criteria for explaining the substantial variation observed among the genotypes. The HMCA successfully grouped genotypes into three distinct clusters and distinguished the salt-tolerant genotypes from the salt-sensitive and intermediate ones. The 24 genotypes/RILs were classified into three main groups according to the allelic data of 40 SSRs associated with salt-tolerant genes. A weak yet significant correlation was observed between the similarity coefficients of agro-morpho-physiological traits and SSR markers, as determined by the Mantel test (r = 0.13, p &lt; 0.03, and alpha = 0.05). In conclusion, this study has successfully identified several traits, particularly those associated with SSR markers, that greatly contribute to our understanding of the phenotypic and genotypic basis influencing the salt tolerance of wheat genotypes in real field conditions. Consequently, assessing these traits for a large number of wheat plant materials in a rapid and cost-effective manner will be greatly importance in breeding programs aimed at improving salt stress tolerance in this vital food crop. This will be the main focus of our forthcoming research.

Physiological Responses of Pak Choi (Brassica rapa Subsp. Chinensis) Genotypes to Salt Tolerance

Salinity stress poses a significant challenge to Pak Choi (Brassica rapa subsp. Chinensis) production. To address this limitation, we conducted an evaluation of 24 Korean native Pak Choi species to identify genotypes with resistance to salt stress. Through cluster analysis of electrolyte leakage data, we discovered ‘IT262109’, ‘IT279432’, and ‘IT185735’ as native accessions displaying the strongest salt tolerance. Additionally, our assessment of the maximum quantum yield of photosystem II revealed a 3.7% reduction in seaweed yield in the highly salt-tolerant system compared with the control group, while the weak salt-tolerant system experienced a substantial reduction rate of 45.7% to 49.4%. Notably, salt stress had a significant impact on Pak Choi growth, but the salt-tolerant genotype exhibited less growth reduction compared with the salt-sensitive genotype. Based on the electrolyte leakage and maximum quantum yield data, it was evident that ‘IT185735’ demonstrated poorer growth compared with ‘IT262109’ and ‘IT279432’. Consequently, ‘IT262109’ and ‘IT279432’ show great potential as parent varieties for enhancing salt tolerance in Pak Choi.

Morpho-physiological profiling of rice (Oryza sativa) genotypes at germination stage with contrasting tolerance to salinity stress.

Salinity is among the harshest environmental stress conditions that negatively affects productivity of salt-sensitive rice. Since, germination is the most crucial phase in the life-cycle of plants, the present study was carried out to study the morpho-physiological traits associated with salinity stress. Evaluation of tolerance in four contrasting rice genotypes was assessed on the basis of specific morpho-physiological parameters including radicle emergence, seedling vigour index, germination index, mean germination time, radicle and plumule growth and seedling water uptake. Largely, our findings revealed that mean germination time (MGT) and seedling vigour index (SVI) are fast-screening procedures to test seedling performance in salt stress conditions. Salt sensitive genotypes showed higher MGT and lower SVI, confirming that these indices are good indicators of poor germination response. Salt-tolerant genotypes were shown to be inhibited to a lesser extent in alpha-amylase activity in spite of high concentrations of imposed NaCl stress, that correlated with better regulation of water-uptake and increased accumulation of total soluble sugar content. Exogenous supplementation of soluble sugars improved the germination rate in a salt sensitive genotype, Jyothi, confirming the importance of soluble sugars in signaling under NaCl stress conditions. Increased total phenols and flavonoids were observed to be relative to higher Total Antioxidant Capacity in salt tolerant genotypes underlying the significance of seed phenolic compounds in early germination response in NaCl stress conditions. Kagga, a landrace grown in coastal Karnataka performed comparably with that of salt tolerant rice, Pokkali. In conclusion, the determination of early seedling response may be utilized as a useful strategy to uncover genetic variation in rice germplasm to salinity stress.

Salinity stress tolerance prediction for biomass-related traits in maize (Zea mays L.) using genome-wide markers.

Maize (Zea mays L.) is the third most important cereal crop after rice (Oryza sativa) and wheat (Triticum aestivum). Salinity stress significantly affects vegetative biomass and grain yield and, therefore, reduces the food and silage productivity of maize. Selecting salt-tolerant genotypes is a cumbersome and time-consuming process that requires meticulous phenotyping. To predict salt tolerance in maize, we estimated breeding values for four biomass-related traits, including shoot length, shoot weight, root length, and root weight under salt-stressed and controlled conditions. A five-fold cross-validation method was used to select the best model among genomic best linear unbiased prediction (GBLUP), ridge-regression BLUP(rrBLUP), extendedGBLUP, Bayesian Lasso, Bayesian ridge regression, BayesA, BayesB, and BayesC. Examination of the effect of different marker densities on prediction accuracy revealed that a set of low-density single nucleotide polymorphisms obtained through filtering based on a combination of analysis of variance and linkage disequilibrium provided the best prediction accuracy for all the traits. The average prediction accuracy in cross-validations ranged from 0.46 to 0.77 across the four derived traits. The GBLUP, rrBLUP, and all Bayesian models except BayesB demonstrated comparable levels of prediction accuracy that were superior to the other modeling approaches. These findings provide a roadmap for the deployment and optimization of genomic selection in breeding for salt tolerance in maize.

Comprehensive Evaluation and Transcriptome Analysis Reveal the Salt Tolerance Mechanism in Semi-Wild Cotton (Gossypium purpurascens).

Elevated salinity significantly threatens cotton growth, particularly during the germination and seedling stages. The utilization of primitive species of Gossypium hirsutum, specifically Gossypium purpurascens, has the potential to facilitate the restoration of genetic diversity that has been depleted due to selective breeding in modern cultivars. This investigation evaluated 45 G. purpurascens varieties and a salt-tolerant cotton variety based on 34 morphological, physiological, and biochemical indicators and comprehensive salt tolerance index values. This study effectively identified a total of 19 salt-tolerant and two salt-resistant varieties. Furthermore, transcriptome sequencing of a salt-tolerant genotype (Nayanmian-2; NY2) and a salt-sensitive genotype (Sanshagaopao-2; GP2) revealed 2776, 6680, 4660, and 4174 differentially expressed genes (DEGs) under 0.5, 3, 12, and 24 h of salt stress. Gene ontology enrichment analysis indicated that the DEGs exhibited significant enrichment in biological processes like metabolic (GO:0008152) and cellular (GO:0009987) processes. MAPK signaling, plant-pathogen interaction, starch and sucrose metabolism, plant hormone signaling, photosynthesis, and fatty acid metabolism were identified as key KEGG pathways involved in salinity stress. Among the DEGs, including NAC, MYB, WRKY, ERF, bHLH, and bZIP, transcription factors, receptor-like kinases, and carbohydrate-active enzymes were crucial in salinity tolerance. Weighted gene co-expression network analysis (WGCNA) unveiled associations of salt-tolerant genotypes with flavonoid metabolism, carbon metabolism, and MAPK signaling pathways. Identifying nine hub genes (MYB4, MYB105, MYB36, bZIP19, bZIP43, FRS2 SMARCAL1, BBX21, F-box) across various intervals offered insights into the transcriptional regulation mechanism of salt tolerance in G. purpurascens. This study lays the groundwork for understanding the important pathways and gene networks in response to salt stress, thereby providing a foundation for enhancing salt tolerance in upland cotton.

Multivariate Analysis in Wheat (Triticum aestivum L.) for Yield and Attributing Traits under Soil Salinity and Alkalinity in Haryana

Salt-affected soils could be used by improving and developing salt-tolerant genotypes depending upon the amount of genetic variation and salt stress response of adapted and donor sources of wheat. Salt stress affects 20% of global cultivable land and is increasing continuously owing to the change in climate and anthropogenic activities. Globally, saline soils cover 3.1% i.e. 397 mha of the total land area and around 6.74 mha area of India is affected due to salinity. Salinity stress negatively affects the growth and development of wheat leading to low grain yield and quality. A station varietal trial was conducted to identify salt-tolerant genotypes, wherein 24 genotypes including 4 checks, namely, KRL 19, WH 157, KRL 210 and KRL 283 were evaluated in 6 replications in 4.0 m x 1.20 m in RBD under natural saline patch (pH 8.5, ECe 4.2 dsm-1) at Research area of Wheat and Barley Section, Department of Genetics and Plant Breeding and Department of Soil Science (pH 8.5, ECe 4.5 dsm-1), CCS HAU, Hisar during Rabi 2021-22. Observations were recorded for germination (%), days to heading, days to maturity, plant height (cm), tillers per meter row, 1000-grain weight (g), grain yield per plot (g/plot) and hectoliter weight (kg/hl). High positive correlation has been observed for 1000-GW (g) with GY/P (g/plot), PH (cm) with hectoliter weight (kg/hl). Non-significant correlation was observed between days to heading and germination with plant height and hectoliter weight. Clustering of genotypes based on Ward’s Euclidean method was done so that identical genotypes may grouped together; 24 genotypes were grouped into three distinct clusters. Hectolitre weight (kg/hl) expressed as point of dissection of studied traits as GY/P (g/plot), 1000-GW (g), DM and PH (cm) falls at one side and germination (%), DH and T/meter row lies at another side. Entries, namely, WH 1313 (59.6 q/ha), WH 1306 (54.9 q/ha) and WH 1309 (52.9 q/ha) performed better and found significantly superior to the best check WH 157 (43.5+8.2 q/ha) at Department of Genetics and Plant Breeding. P 13582 (61.6 q/ha), P 13650 (62.1 q/ha) performed better and found significantly superior to best check KRL 283 (46.4+13.7 q/ha) at Department of Soil Sciences. Identification of wheat genotypes based on simultaneous selection among contributing traits will improve grain yield. Stable and promising genotypes may be included in breeding program aimed to develop salt tolerant varieties at state and national level to ensure nutritional food security.

Screening of Sweet Sorghum Genotypes for Salt Tolerance and Comparative Na+ Transporter Gene Expression in Salt Tolerance Differing Genotypes at Seedling Growth Stage

Screening of Sweet Sorghum Genotypes for Salt Tolerance and Comparative Na+ Transporter Gene Expression in Salt Tolerance Differing Genotypes at Seedling Growth Stage

Morpho-physiological and genetic characteristics of a salt-tolerant mutant line in soybean (Glycine max L.)

Morpho-physiological and genetic characteristics of a salt-tolerant mutant line in soybean (Glycine max L.)

From salty to thriving: plant growth promoting bacteria as nature's allies in overcoming salinity stress in plants.

Soil salinity is one of the main problems that affects global crop yield. Researchers have attempted to alleviate the effects of salt stress on plant growth using a variety of approaches, including genetic modification of salt-tolerant plants, screening the higher salt-tolerant genotypes, and the inoculation of beneficial plant microbiome, such as plant growth-promoting bacteria (PGPB). PGPB mainly exists in the rhizosphere soil, plant tissues and on the surfaces of leaves or stems, and can promote plant growth and increase plant tolerance to abiotic stress. Many halophytes recruit salt-resistant microorganisms, and therefore endophytic bacteria isolated from halophytes can help enhance plant stress responses. Beneficial plant-microbe interactions are widespread in nature, and microbial communities provide an opportunity to understand these beneficial interactions. In this study, we provide a brief overview of the current state of plant microbiomes and give particular emphasis on its influence factors and discuss various mechanisms used by PGPB in alleviating salt stress for plants. Then, we also describe the relationship between bacterial Type VI secretion system and plant growth promotion.