To explore the role of H2S signal in regulating stomatal movement in alfalfa and the relationship between H2S and Ca2+ during this process， wild type and the calcium transporter mutants of Medicago truncatula were used as experimental materials， and the transcriptional level， cellular level and physiological level were studied respectively， and the expression levels of related genes were compared by qRT-PCR， the content of Ca2+in vivo was detected by fluorescent probe， the content of H2S was measured by electrode method， and the stomatal aperture was observed by microscope respectively. The results showed that compared with the wild type， the content of H2S in the mutant NF3011 and NF2734 decreased significantly； the H2S signal inhibited the expression of calcium transporter encoding gene MTR_6g027580， the exogenous physiological concentration of H2S fumigation could induce stomatal closure of Medicago truncatula， and the combination of treatment with LaCl3， Ca2+ channel blocker， had no effect on stomatal movement of wild type， but opposite in mutant； the concentration of Ca2+ in guard cells was measured by fluorescence probe， which were consistent with the change law of stomatal aperture. In conclusion， the content of Ca2+ in guard cells of leaves is induced by H2S， whose stomatal aperture become smaller at the same time. In this process， the change of intracellular Ca2+ concentration mainly depend on Ca2+ transporter， and small partly depend on Ca2+ channel. The results of this study not only enrich the mechanism of H2S signaling in theory， but also have the potential to be applied to alfalfa production and other crops.
%U https://bbr.nefu.edu.cn/EN/10.7525/j.issn.1673-5102.2023.02.013