Hydrogen sulfide priming can enhance the tolerance of artichoke seedlings to individual and combined saline-alkaline and aniline stresses

Regulatory roles of hydrogen sulfide (H2S) under saline-alkaline and/or aniline stress have not been studied yet. In this study, we investigated the insights into saline-alkaline and/or aniline stresses-induced toxicity in artichoke plants and its alleviation by H2S priming. Individual saline-alkaline or aniline stress and their combination reduced plant growth and photosynthetic pigments. Principal component analysis (PCA) revealed that these detrimental impacts were caused by the higher oxidative damage and disruption of osmolyte homeostasis. Interestingly, only aniline stress (25 mg L-1) caused neither oxidative nor osmotic stress thus almost slight growth retarding effects had ensued. On the other hand, the presence of aniline in saline-alkaline conditions exacerbated stress-induced deleterious effects on plants, as evidenced by PCA and heatmap. However, H2S priming markedly eased the stress-induced deleteriousness as evident by enhanced chlorophyll, soluble proteins, soluble carbohydrates and up-regulated water relation in H2S-primmed plants compared with only stressed plants resulting in improved plant phenotypic features. Furthermore, H2S priming enhanced endogenous H2S content, phenylalanine ammonia-lyase, non-enzymatic antioxidants (ascorbic acid, flavonoids, glutathione, alpha-tocopherol, and anthocyanins) and enzymatic antioxidants (superoxide dismutase, catalase, and ascorbate peroxidase), whereas reduced oxidative stress markers (superoxide, hydrogen peroxide, hydroxyl radical, malondialdehyde, and methylglyoxal) compared with only stressed plants, indicating a protective function of H2S against oxidative damage. The PCA also clarified that H2S-mediated saline-alkaline and/or aniline stress tolerance strongly connected with the improved antioxidant system. Overall, our finding proposed that H2S priming could be an effective technique to mitigate saline-alkaline and/or aniline stress in artichoke, and perhaps in other crop plants.

Automated summary

The study found that H2S priming can protect artichoke plants under saline-alkaline and/or aniline stress, mitigate the detrimental effects of stress, and enhance stress tolerance by improving the antioxidant system.