Signaling Mechanism Of H₂S Regulating Seed Germination In Wheat Under Cr（Ⅵ） Stress

Wheat is the important food crops, Chromium(Cr) has toxic on the wheat growth. This paper studied the effect of Cr(VI) salt on wheat seed germination, and H2S(Hydrogen Sulfide, H2S) donor, sodium hydride(NaHS) alleviated Cr(VI) toxicity on wheat seedlings.Study the effect of Cr(VI) salt on wheat seed germination, the results show that the Cr(VI) salt inhibit wheat seed germination, hinder the growth of wheat seed radicle germ; The Cr(VI) resistance of wheat half lethal and lethal concentration is 6 mmol/L, 12 mmol/L; Cr(VI) salt stress can reduce the amylase activity in the process of wheat seed germination; Cr(VI) salt on wheat seed germination inhibition may be by inhibiting the amylase activity.Research on the effect of H2 S on wheat seed germination and seedling growth under Cr(VI) salt stress, the results show that NaHS pretreatment can alleviate Cr(VI) stress on wheat seed germination and seedling growth inhibition, but there is no obvious influence on the growth of radicle, The most suitable NaHS concentration was 0.08 mM.Research the effect of H2 S on the metabolism and the activities of hydrolytic enzymes under Cr(VI) stress, found that H2 S donor NaHS can improve the wheat seed germination and seedling growth process of soluble sugar, soluble protein and proline content; Promoted the wheat seed germination in the process of total amylase and α-amylase enzyme activity rose, The most suitable NaHS concentration was 0.08 mM..Further study the effect of H2 S on the antioxidant metabolism under Cr(VI) stress in wheat seedlings, the results show that H2 S donor NaHS can induce wheat seedling growth under Cr(VI) stress in the process of hydrogen peroxide enzyme(catalase, CAT), guaiacol peroxidase and superoxide dismutase(SOD), peroxidase(POD), three important antioxidant enzyme activity, and the optimal processing concentration tendency for 0.08 mmol/ L; NaHS pretreatment at the same time reduces the ultra oxygen anion(.O2-) and Malondialdehyde, Malondialdehyde(MDA) content, reduce the peroxidation damage of wheat seedlings, enhances the Cr(VI) the resistance of wheat seedling growth stage, for the normal growth and development of wheat seed provides a favorable conditions.In all, H2 S as a signal molecule can be mediated crops on Cr(VI) under the stress of antioxidant response, helps relieve the stress of Cr(VI) oxidative damage to crops, enhance crop resistance.