DataSheet_1_Exogenous spermine alleviates the negative effects of combined salinity and paraquat in tomato plants by decreasing stress-induced oxidative damage.pdf

Plants are frequently exposed to different combinations of soil constraints including salinity and different herbicides. These abiotic conditions negatively affect photosynthesis, growth and plant development resulting in limitations in agriculture production. To respond to these conditions, plants accumulate different metabolites that restore cellular homeostasis and are key for stress acclimation processes. In this work, we analyzed the role of exogenous spermine (Spm), a polyamine involved in plant tolerance to abiotic stress, in tomato responses to the combination of salinity (S) and the herbicide paraquat (PQ). Our findings showed that application of Spm reduced leaf damage and enhanced survival, growth, photosystem II function and photosynthetic rate of tomato plants subjected to the combination of S and PQ. In addition, we revealed that exogenous Spm reduced H2O2 and malondialdehyde (MDA) accumulation in plants subjected to S+PQ, suggesting that the role of exogenous Spm in alleviating the negative effects of this stress combination could be attributed to a decrease in stress-induced oxidative damage in tomato plants. Taken together, our results identify a key role for Spm in improving plant tolerance to combined stress.

植物常暴露于多种土壤限制条件的复合影响，包括盐分及不同的除草剂。这些非生物条件对光合作用、植物生长及发育产生负面影响，进而限制了农业生产。为应对这些环境，植物积累不同代谢产物，以恢复细胞稳态并成为应对胁迫的关键过程。在本研究中，我们分析了外源精胺（Spm），一种参与植物对非生物胁迫耐受的聚胺，在番茄对盐分（S）和除草剂双甲脒（PQ）复合胁迫反应中的作用。我们的研究结果揭示了Spm的应用降低了受S和PQ复合胁迫的番茄叶片损伤，并提高了其存活率、生长、光合系统II功能和光合速率。此外，我们发现外源Spm减少了受S+PQ胁迫植物的H2O2和丙二醛（MDA）积累，这表明外源Spm在缓解该胁迫组合的负面效应中可能通过降低番茄植物中胁迫诱导的氧化损伤来实现。综合来看，我们的研究结果确定了Spm在提高植物对复合胁迫耐受性中的关键作用。