文献类型： 外文期刊

作者： He, Li ¹ ; Wang, Xiaomin ¹ ; Na, Xiaofan ¹ ; Feng, Ruijun ² ; He, Qiang ² ; Wang, Shengwang ² ; Liang, Cuifang ² ; Yan, Lili ² ; Zhou, Libin ⁴ ; Bi, Yurong ¹ ;

作者机构： 1.State Key Lab Hulless Barley & Yak Germplasm Reso, Lhasa 850002, Peoples R China

2.Lanzhou Univ, Sch Life Sci, Key Lab Cell Act & Stress Adaptat, Minist Educ, Lanzhou 730000, Peoples R China

3.Lanzhou Jiaotong Univ, Sch Biol & Pharmaceut Engn, Lanzhou 730070, Peoples R China

4.Chinese Acad Sci, Inst Modern Phys, Biophys Grp, Lanzhou 730000, Peoples R China

关键词： alternative pathway; Cd stress; hulless barley; hydrogen peroxide; reactive oxygen species

期刊名称：PLANTS-BASEL （ 影响因子：4.658； 五年影响因子：4.827 ）

ISSN：

年卷期： 2021 年 10 卷 11 期

页码：

收录情况： SCI

摘要： Hulless barley, grown in the Qinghai Tibet Plateau, has a wide range of environmental stress tolerance. Alternative pathway (AP) and hydrogen peroxide (H2O2) are involved in enhancing plant tolerance to environmental stresses. However, the relationship between H2O2 and AP in hulless barley tolerance to cadmium (Cd) stress remains unclear. In the study, the role and relationship of AP and H2O2 under Cd stress were investigated in hulless barley (Kunlun14) and common barley (Ganpi6). Results showed that the expression level of alternative oxidase (AOX) genes (mainly AOX1a), AP capacity (V-alt), and AOX protein were clearly induced more in Kunlun14 than in Ganpi 6 under Cd stress; moreover, these parameters were further enhanced by applying H2O2. Malondialdehyde (MDA) content, electrolyte leakage (EL) and NAD(P)H to NAD(P) ratio also increased in Cd-treated roots, especially in Kunlun 14, which can be markedly alleviated by exogenous H2O2. However, this mitigating effect was aggravated by salicylhydroxamic acid (SHAM, an AOX inhibitor), suggesting AP contributes to the H2O2-enhanced Cd tolerance. Further study demonstrated that the effect of SHAM on the antioxidant enzymes and antioxidants was minimal. Taken together, hulless barley has higher tolerance to Cd than common barley; and in the process, AP exerts an indispensable function in the H2O2-enhanced Cd tolerance. AP is mainly responsible for the decrease of ROS levels by dissipating excess reducing equivalents.