Study On The Mechanism Of Hydrogen Sulfide And Phytohormones Crosstalk In Regulating Seed Germination

Seed germination is an important initial stage of plant life cycle,which is related to the subsequent growth of plants and determines the final yield of crops.Therefore,it has always been a research hotspot in the field of botany,and people continue to explore its regulatory mechanism from various angles.Hydrogen sulfide(H₂S),as a signal molecule with broad-spectrum effect,has also been reported to play a role in seed germination.However,most studies focus on how H₂S alleviates the inhibition of abiotic stress on germination,and the regulation mechanism of H₂S,especially endogenous H₂S,on seed germination under normal growth conditions remains unclear.Therefore,with Arabidopsis thaliana as the research material,we found that exogenous H₂S had a dual effect on seed germination.Low concentration of Na HS treatment significantly promoted seed germination,while high concentration of Na HS treatment significantly inhibited seed germination.Moreover,we also proved that the sulfur metabolism pathway was related to the regulation of seed germination by H₂S,in which cysteine promoted seed germination by increasing the production of H₂S.And also,the seed germination regulated by H₂S may not depend on the change of reactive oxygen species.Then,we found that phytohormones were involved in the regulation of H₂S on seed germination.Low concentration of Na HS was antagonistic to abscisic acid(ABA)and auxin(IAA),while high concentration of Na HS was antagonistic to gibberellin(GA),ethylene(ETH),brassinosteroid(BR),cytokinin(CTK)and salicylic acid(SA).Further studies have shown that exogenous H₂S may change the synthesis,metabolism and signal transduction of endogenous hormones in seeds by regulating the expression of related genes,thereby affecting seed germination.In addition,we preliminarily explored the regulation of phytohormones on endogenous H₂S,and found that ABA and ETH interacted with H₂S,while GA,BR,CTK and SA might act on the upstream of H₂S at different stages of germination.This study focused on the effects of H₂S on phytohormones in m RNA during seed germination,which provided new insights for improving the regulation mechanisms of seed germination and the interaction network of H₂S,and had certain theoretical value.