Melatonin improves antioxidant capacity and ion homeostasis and enhances salt tolerance in maize seedlings

Abstract Plant heat shock transcription factors (HSFs) are involved in heat and other abiotic stress responses. However, their functions in salt tolerance are little known. In this study, we characterized the function of a HSF from Arabidopsis, AtHSFA7b, in salt tolerance. AtHSFA7b is a nuclear protein with transactivation activity. ChIP-seq combined with an RNA-seq assay indicated that AtHSFA7b preferentially binds to a novel cis-acting element, termed the E-box-like motif, to regulate gene expression; it also binds to the heat shock element motif. Under salt conditions, AtHSFA7b regulates its target genes to mediate serial physiological changes, including maintaining cellular ion homeostasis, reducing water loss rate, decreasing reactive oxygen species accumulation, and adjusting osmotic potential, which ultimately leads to improved salt tolerance. Additionally, most cellulose synthase-like (CSL) and cellulose synthase (CESA) family genes were inhibited by AtHSFA7b; some of them were randomly selected for salt tolerance characterization, and they were mainly found to negatively modulate salt tolerance. By contrast, some transcription factors (TFs) were induced by AtHSFA7b; among them, we randomly identified six TFs that positively regulate salt tolerance. Thus, AtHSFA7b serves as a transactivator that positively mediates salinity tolerance mainly through binding to the E-box-like motif to regulate gene expression.

Download Full-text

OsCYP714D1 improves plant growth and salt tolerance through regulating gibberellin and ion homeostasis in transgenic poplar

Plant Physiology and Biochemistry ◽

10.1016/j.plaphy.2021.10.023 ◽

2021 ◽

Author(s):

Hongsheng Gao ◽

Huiqing Huang ◽

Kaifeng Lu ◽

Cuiting Wang ◽

Xiaohua Liu ◽

...

Keyword(s):

Salt Tolerance ◽

Plant Growth ◽

Ion Homeostasis ◽

Transgenic Poplar

Download Full-text

Growth, Phenolics, Photosynthetic Pigments, and Antioxidant Response of Two New Genotypes of Sea Asparagus (Salicornia neei Lag.) to Salinity under Greenhouse and Field Conditions

Agriculture ◽

10.3390/agriculture8070115 ◽

2018 ◽

Vol 8 (7) ◽

pp. 115 ◽

Cited By ~ 8

Author(s):

Manuel de Souza ◽

Carlos Mendes ◽

Kennia Doncato ◽

Eliana Badiale-Furlong ◽

César Costa

Keyword(s):

Salt Tolerance ◽

Antioxidant Capacity ◽

Bioactive Compound ◽

Antioxidant Response ◽

Field Conditions ◽

Carotenoid Content ◽

Water Yield ◽

Wide Range ◽

Flavonoid Quercetin ◽

High Yields

Small succulent halophytic shrubs of the genera Salicornia and Sarcocornia (Salicornioideae, Amaranthaceae) are commonly named sea asparagus and consumed worldwide as green salad in gourmet food, as conserves, and beverages. Their shoots are rich in bioactive compounds and plants show high yields in a wide range of salinities, but little is known about how salt cultivation conditions affect their chemical composition. Two genotypes (BTH1 and BTH2) of the Brazilian sea asparagus Salicornia neei Lag. were evaluated for salt tolerance and changes in shoot concentrations of organic metabolites and antioxidant activity under different salt exposure in both greenhouse and field conditions. All greenhouse plants received full strength modified Hoagland solution in deionized water with a basic electrical conductivity (EC) of 1.7 dS m−1, and with NaCl concentrations (in mM) of ~0.1 (control), 34, 86, 171, 513, and 769. After fifty days of cultivation, both S. neei genotypes showed high salt tolerance and grew better under low salinities (34–86 mM NaCl) than under control salinity. Shoots of BTH1 genotype appeared to be undergoing lignification and used their high carotenoid content to dissipate the oxidative power, and the zeaxanthin content and de-epoxidation state of xanthophylls (DES) were positively affected by salinity. Under increasing salinity, BTH2 genotype had higher relative content of chlorophyll b, which may have lowered the plant photo-oxidation rate, and increased shoot concentration of the flavonoid quercetin (up to 11.6 μg g−1 dw at 769 mM NaCl), leading to higher antioxidant capacity. In the field experiment, after 154 days of irrigation with saline (213 mM NaCl) shrimp farm effluent, BTH2 plants grew taller, produced more metabolites (e.g., total phenolics, total free flavonoids, quercetin, and protocatechuic acid) and had a greater antioxidant capacity of shoots than that of BTH1 plants and that of traditional crops irrigated with fresh water. Yield and bioactive compound composition of S. neei genotypes’ shoots can be enhanced by cultivation under moderate saline conditions.

Download Full-text

Screening and Evaluation of Saline–Alkaline Tolerant Germplasm of Rice (Oryza sativa L.) in Soda Saline–Alkali Soil

Agronomy ◽

10.3390/agronomy8100205 ◽

2018 ◽

Vol 8 (10) ◽

pp. 205 ◽

Cited By ~ 8

Author(s):

Hao Wang ◽

Tetsuo Takano ◽

Shenkui Liu

Keyword(s):

Survival Rate ◽

Salt Tolerance ◽

Antioxidant Capacity ◽

Soluble Sugars ◽

Natural State ◽

Salt Tolerant ◽

Alkali Soil ◽

Alkaline Tolerance ◽

Tolerant Variety ◽

Alkaline Tolerant

The improvement and development of saline–alkali land is of great significance for promoting food production and sustainable development. It is necessary to study the mechanism of saline–alkaline tolerance and breed saline–alkaline tolerant crops to improve the utilization of saline–alkali land. For this study, we conducted a three-year pot experiment to screen the saline–alkaline tolerant germplasm of 72 rice genotypes from hundreds of elite cultivars during the whole growth period using a certain proportion of soda saline–alkali soil. The selected salt-tolerant variety was combined with a salt-sensitive variety to analyze the saline–alkaline tolerance mechanism by using the saline–alkaline soil leachate. We eliminated 36 genotypes with low seedling survival rates under salt–alkali stress, and the salt-tolerant Jiudao-66 (D68) variety had a higher survival rate than most varieties. The membership degree of Jiudao-66, according to the salt tolerance index of multiple agronomic traits, is higher than that of 34 varieties, with a higher survival rate except when compared to D36. The survival rate and these salt tolerance indexes of Jiudao-66 were significantly higher than those of Kitaake (salt-sensitive). Under the stress of leachate, the content of proline and soluble sugars in the shoots of Jiudao-66 were higher than that of Kitaake, and the total antioxidant capacity was stronger than that of Kitaake. However, the content of malondialdehyde was lower than that of Kitaake. Additionally, the Na+/K+ ratios in shoots and roots were not significantly differently between Kitaake and Jiudao-66. The results showed that Jiudao-66, as a salt-tolerant variety, is more tolerant to salt and alkali in a near-natural state due to its stronger tolerance of osmotic stress, and it can accumulate more proline and soluble sugars under stress. At the same time, Jiudao-66 also has a stronger antioxidant capacity. Its ion regulation ability has no obvious advantage.

Download Full-text

Silver Nanoparticle Regulates Salt Tolerance in Wheat Through Changes in ABA Concentration, Ion Homeostasis, and Defense Systems

Biomolecules ◽

10.3390/biom10111506 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1506

Author(s):

Iram Wahid ◽

Sarika Kumari ◽

Rafiq Ahmad ◽

Sofi J. Hussain ◽

Saud Alamri ◽

...

Keyword(s):

Salt Tolerance ◽

Silver Nanoparticle ◽

Defense Mechanisms ◽

Ion Homeostasis ◽

Agricultural Practices ◽

Crop Productivity ◽

Enzymatic Antioxidants ◽

Oxidative Biomarkers ◽

Aba Content

Salinity is major abiotic stress affecting crop yield, productivity and reduces the land-usage area for agricultural practices. The purpose of this study is to analyze the effect of green-synthesized silver nanoparticle (AgNP) on physiological traits of wheat (Triticum aestivum) under salinity stress. Using augmented and high-throughput characterization of synthesized AgNPs, this study investigated the proximity of AgNPs-induced coping effects under stressful cues by measuring the germination efficiency, oxidative-biomarkers, enzymatic and non-enzymatic antioxidants, proline and nitrogen metabolism, stomatal dynamics, and ABA content. Taken together, the study shows a promising approach in salt tolerance and suggests that mechanisms of inducing the salt tolerance depend on proline metabolism, ions accumulation, and defense mechanisms. This study ascertains the queries regarding the correlation between nanoparticles use and traditional agriculture methodology; also significantly facilitates to reach the goal of sustainable developments for increasing crop productivity via much safer and greener approachability.

Download Full-text

Salt Tolerance and Na Allocation in Sorghum bicolor under Variable Soil and Water Salinity

Plants ◽

10.3390/plants9050561 ◽

2020 ◽

Vol 9 (5) ◽

pp. 561 ◽

Cited By ~ 2

Author(s):

Roberta Calone ◽

Rabab Sanoubar ◽

Carla Lambertini ◽

Maria Speranza ◽

Livia Vittori Antisari ◽

...

Keyword(s):

Salt Tolerance ◽

Plant Growth ◽

Sorghum Bicolor ◽

Soil Salinity ◽

Ion Homeostasis ◽

Dry Weight ◽

Water Salinity ◽

Selective Absorption ◽

Salt Leaching ◽

Sensitive Organ

Salinity is a major constraint for plant growth in world areas exposed to salinization. Sorghum bicolor (L.) Moench is a species that has received attention for biomass production in saline areas thanks to drought and salinity tolerance. To improve the knowledge in the mechanisms of salt tolerance and sodium allocation to plant organs, a pot experiment was set up. The experimental design combined three levels of soil salinity (0, 3, and 6 dS m−1) with three levels of water salinity (0, 2–4, and 4–8 dS m−1) and two water regimes: no salt leaching (No SL) and salt leaching (SL). This latter regime was carried out with the same three water salinity levels and resulted in average +81% water supply. High soil salinity associated with high water salinity (HSS-HWS) affected plant growth and final dry weight (DW) to a greater extent in No SL (−87% DW) than SL (−42% DW). Additionally, HSS-HWS determined a stronger decrease in leaf water potential and relative water content under No SL than SL. HSS-HWS with No SL resulted in a higher Na bioaccumulation from soil to plant and in translocation from roots to stem and, finally, leaves, which are the most sensitive organ. Higher water availability (SL), although determining higher salt input when associated with HWS, limited Na bioaccumulation, prevented Na translocation to leaves, and enhanced selective absorption of Ca vs. Na. At plant level, higher Na accumulation was associated with lower Ca and Mg accumulation, especially in No SL. This indicates altered ion homeostasis and cation unbalance.

Download Full-text