水分胁迫对小麦幼苗中活性氧与细胞死亡的影响

Effects of Water Stress on Reactive Oxygen Species and Cell Death in Wheat Seedlings

【目的】研究水分胁迫迫对抗旱与干旱敏感型小麦幼苗叶片活性氧与细胞死亡的影响。【方法】本实验选用2个耐旱性差异显著的小麦品种为材料,分析水分胁迫对小麦幼苗中脯氨酸含量、活性氧水平和细胞死亡程度等指标的影响。【结果】水分胁迫对旱选10号的叶片含水量、叶片渗透势和生物量影响相对较小,其下降幅度均低于郑引1号;叶片中脯氨酸(Pro)含量和根系活力的上升幅度则显著高于郑引1号;而叶片中丙二醛(MDA)含量和相对电导率上升幅度显著低于郑引1号。水分胁迫下,旱选10号叶片与根尖部位的H_2O_2含量、O^-_2水平及细胞死亡率也显著低于郑引1号。【结论】说明在水分胁迫下,旱选10号可以通过减缓体内活性氧积累,增加脯氨酸含量与根系活力和降低细胞死亡程度,从而增强了其对胁迫的耐受能力。

【Objective】The experiment aimed to study the effects of water stress on leaves reactive oxygen species and cell death in droughtresistant and drought-sensitive wheat seedlings.【Method】In this study two wheat cultivars with contrasting drought tolerance were used as materials to analyze the effects of water stress on proline content,reactive oxygen level and cell death degree in wheat seedlings.【Result】The results showed that water stress affected less on leaf water content,leaf osmotic potential and seedling biomass of Hanxuan10 than that of Zhengyin1.Under water stress,the increasement of proline(Pro)content and root activity in Hanxuan10 was significantly higher than that in Zhengyin1,while malondialdehyde(MDA)content and relative conductivity in leaves were significantly lower in Hanxuan10.Moreover,H2O2 content,O-2 level and cell death rate in leaves and root tips of Hanxuan10 were also significantly lower than that of Zhengyin1 under water stress.【Conclusion】It indicated that Hanxuan10 could enhance tolerance to stress by reducing the accumulation of reactive oxygen,increasing proline content and root activity and reducing cell death.