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Karrikinolide (KAR1), identified in biochars, has gained research attention because of its significant role in seed germination, seedling development, root development, and abiotic stresses. However, KAR1 regulation of salt stress in wheat is elusive. This study investigated the physiological mechanism involved in KAR1 alleviation of salt stress in wheat. The results showed KAR1 boosted seed germination percentage under salinity stress via stimulating the relative expression of genes regulating gibberellins biosynthesis and decreasing the expression levels of abscisic acid biosynthesis and signaling genes. As seen in seed germination, exogenous supplementation of KAR1 dramatically mitigated the salt stress also in wheat seedling, resulting in increased root and shoot growth as measured in biomass as compared to salt stress alone. Salt stress significantly induced the endogenous hydrogen peroxide and malondialdehyde levels, whereas KAR1 strictly counterbalanced them. Under salt stress, KAR1 supplementation showed significant induction in reduced glutathione (GSH) and reduction in oxidized glutathione (GSSG) content, which improved GSH/GSSG ratio in wheat seedlings. Exogenous supplementation of KAR1 significantly promoted the activities of enzymatic antioxidants in wheat seedlings exposed to salt stress. KAR1 induced the relative expression of genes regulating the biosynthesis of antioxidants in wheat seedlings under salinity. Moreover, KAR1 induced the expression level of K+/Na+ homeostasis genes, reduced Na+ concentration, and induced K+ concentration in wheat seedling under salt stress. The results suggest that KAR1 supplementation maintained the redox and K+/Na+ homeostasis in wheat seedling under salinity, which might be a crucial part of physiological mechanisms in KAR1 induced tolerance to salt stress. In conclusion, we exposed the protective role of KAR1 against salt stress in wheat.

Silver nanoparticles (AgNPs) synthesized from plant extracts have recently emerged as a rapidly growing field with numerous applications in pharmaceutical and clinical contexts. The purpose of this research is to come up with a novel method for the biosynthesis of silver nanoparticles that use

Hydrogen sulphide (H

Aflatoxin B1 (AFB1) is the most harmful mycotoxin produced by filamentous fungi and presents a serious threat to human and animal health. Therefore, it is essential to protect humans and animals from AFB1-induced acute and chronic toxicity. In this study, Pseudomonas strain m29 having a high efficiency of AFB1 transformation was isolated from soil. The transformation ratio by m29 was more than 97% within 24 h, and the optimum temperature for transformation was 37°C. Moreover, the AFB1 transforming activity was mainly attributed to the cell-free supernatant of strain m29. The metabolite that plays a crucial role in AFB1 transformation is likely 1,2-dimethylhydrazine or 1,1-dimethylhydrazine, as identified by GC-MS and LC-MS analysis. AFB1 was transformed into a product with molecular formula C17H14O7. To the best of our knowledge, this is the first study of non-enzymatic AFB1 transformation by bacteria. Importantly, this AFB1 transformation mechanism could be universal to various microorganisms.

Karrikinolide (KAR

Hydrogen sulphide (H2S), a crucial gas signal molecule, has been reported to be involved in various processes related to development and adversity responses in plants. However, the effects and regulatory mechanism of H2S in controlling Fusarium head blight (FHB) in wheat have not been clarified. In this study, we first reported that H2S released by low concentrations of sodium hydrosulphide (NaHS) could significantly alleviate the FHB symptoms caused by Fusarium graminearum (F. graminearum) in wheat. We also used coleoptile inoculation to investigate the related physiological and molecular mechanism. The results revealed that FHB resistance was strongly enhanced by the H2S released by NaHS, and 0.3 mM was confirmed as the optimal concentration. H2S treatment dramatically reduced the levels of hydrogen peroxide (H2O2) and malondialdehyde (MDA) while enhancing the activities of antioxidant enzymes. Meanwhile, the relative expressions levels of defence-related genes, including PR1.1, PR2, PR3, and PR4, were all dramatically upregulated. Our results also showed that H2S was toxic to F. graminearum by inhibiting mycelial growth and spore germination. Taken together, the findings demonstrated the potential value of H2S in mitigating the adverse effects induced by F. graminearum and advanced the current knowledge regarding the molecular mechanisms in wheat.