田菁根系对长期淹水处理的生理响应

Physiological Response of Sesbania cannabina Roots to Long-Term Flooding Stress

以田菁为材料,采用土壤培养模拟淹水试验,设置淹水(超过盆栽苗表土5cm)和不淹水(正常土壤水分)处理,分析其根系在淹水60d时的生理生化响应。结果表明:淹水处理后,田菁茎基部产生了白色海绵状组织和不定根来适应淹水环境。与对照相比,田菁一级根、二级根的根系活力、O2·^-产生速率及CAT活性均显著降低,SOD、POD活性及可溶性糖、可溶性蛋白含量显著升高,相对电导率及MDA含量也有不同的变化。田菁经过长时间的淹水后其根系仍表现出较强的生理适应性,通过调节抗氧化系统及渗透调节物质含量来适应长期淹水环境,表明其对土壤淹水处理具有较强的适应能力,可用于湿地及水库消落带植被恢复。

In this study,the physiological responses of Sesbania cannabina roots to long-term water flooding stress were investigated.The seedlings of Sesbania cannabina were cultivated in soils with flooding treatment(5 cm of water layer above the soil surface)and nonflooding treatment(ordinary cultivation)respectively.Under flooding condition,white spongy tissue and adventitious roots emerged from stem base to adapt to the flooding condition.The results showed that,compared with CK,the root activity,content of O2·^-and activity of CAT significantly decreased under flooding condition,but the activity of SOD and POD,and contents of soluble sugar and soluble protein in roots markedly increased.The relative electron conductivity and MDA content changed slightly as affected by soil flooding.Sesbania cannabina showed strong physiological adaptation to long-term flooded period,which indicated that it may adapt in vegetation restoration of wetland and hydro-fluctuation belt.