[Effects of hydrogen sulfide on mitochondrial function in sweet cherry stigma and ovary under low temperature stress]

To investigate the effects of H₂S on mitochondrial functions under low temperature stress, we analyzed the effects of 0.05 mmol·L^-1 NaHS and 15 μmmol·L^-1 HT (hypotaurine and H₂S scavenger) on mitochondria antioxidant enzyme activities and mitochondrial permeability transition pore, mitochondrial membrane fluidity, mitochondrial membrane potential, Cyt c/a ratio and H⁺-ATPase activity in sweet cherry stigma and ovary with sweet cherry variety Zaodaguo under -2 ℃ low temperature stress. The results showed that low temperature stress increased the concentrations of mitochondrial H₂O₂ and MDA, enhanced the mitochondrial membrane permeability, but decreased the mitochondrial membrane fluidity, membrane potential, Cyt c/a and H⁺-ATPase acti-vity. Application of NaHS at 0.05 mmol·L^-1 could effectively reduce the concentrations of H₂O₂ and MDA, and keep higher activities of SOD, POD and CAT of mitochondrial for longer time. Furthermore, application of 0.05 mmol·L^-1 NaHS could decrease mitochondrial membrane permeability while increase mitochondrial membrane fluidity, membrane potential, Cyt c/a and H⁺-ATPase activity in stigma and ovary under low temperature stress. The effects of NaHS were completely offset by HT addition. The results suggested that exogenous H₂S could alleviate the oxidative damage on stigma and ovary stress through decreasing H₂O₂ accumulation, regulating mitochondria antioxidant system, increasing H⁺-ATPase activity, and mitigating mitochondria function under low temperature.