Abstract: This study was conducted to determine the effects of sodium hydrosulfide which is the donor of exogenous hydrogen sulfide (H₂S) on the morphological indicators,photosynthetic pigment,membrane permeability and endogenous hormones of tall fescue (‘Arid3’) under different kinds of light intensity (100,75,50 and 25 μmol·m^-2·s^-1),in order to provide theoretical basis for molecular breeding of shade-tolerant turfgrass. The results showed that the morphological and physiological indexes of tall fescue decreased with different degrees with the decrease of light intensity. Spraying exogenous H₂S donor could significantly increase the content of photosynthetic pigment,reduce the relative conductivity and MDA content (P<0.05),especially when light intensity was 50 and 75 μmol·m^-2·s^-1. Meanwhile,the exogenous H₂S donor could promote the content of abscisic acid (ABA),gibberellin (GA) and hydrogen sulfide under suitable low light. In conclusion,the application of exogenous H₂S can improve the shade tolerance of tall fescue by protecting the integrity of cell membrane,increasing photosynthetic pigment and endogenous hormone content under suitable low light stress.

Key words: Hydrogen sulfide, Tall fescue, Low light stress, Cell membrane stability, Endogenous hormone

摘要： 本研究以冷季型草坪草高羊茅‘Arid3’（Festuca arundinacea Schreb.‘Arid3’）为研究材料，采用室内模拟弱光胁迫，研究喷施外源硫化氢（H₂S）供体硫氢化钠对不同光照强度（100，75，50和25 μmol·m^-2·s^-1）处理下高羊茅形态指标、光合色素、细胞膜透性和内源激素的影响，旨在为耐荫草坪草分子育种提供理论基础。研究结果显示：随着光照强度的降低，高羊茅形态指标和生理指标都不同程度的降低，而喷施外源H₂S供体能够显著提高光合色素含量，降低相对电导率和丙二醛含量（P<0.05），且在光照强度为50 μmol·m^-2·s^-1和75 μmol·m^-2·s^-1时效果较为显著。同时，喷施外源H₂S供体能够促进适度弱光下高羊茅内源脱落酸（Abscisic acid，ABA）、赤霉素（Gibberellin，GA）和硫化氢含量的增加（P<0.05）。综上，适度的弱光下，外源H₂S通过提高高羊茅内源激素含量，保护细胞膜完整性，增加光合色素含量，提高高羊茅的耐荫性。

关键词: 硫化氢, 高羊茅, 弱光胁迫, 细胞膜稳定性, 内源激素