【摘要】 选取三峡库区自然消落带野生狗牙根(XC)和非消落带野生狗牙根(FC)为研究对象,采用三重复裂区设计试验,主区为两品种,副区为6个不同深度水淹处理(0,1,2,5,10m和15m),分析了各处理植株几种酶活性和碳水化合物含量的变化情况。结果显示:①不同生境狗牙根受深淹胁迫后,丙二醛(MDA)都呈递增趋势,表明狗牙根在深淹胁迫下受到了不同程度的膜脂过氧化伤害,且随胁迫程度的增加受伤害增大。②超氧化物歧化酶(SOD)、过氧化物酶(POD)、谷胱甘肽还原酶(GR)活性和醇脱氢酶(ADH)活性较对照都有所增加;XC处理POD和SOD的最大值出现在5m深水淹处理,而FC出现在2m深处理,且XC5米深淹处理GR值较对照和其他处理明显大;各受淹处理地下茎可溶性糖含量和淀粉含量都保持在较高水平。③从抗氧化酶活性和ADH活性的变化规律,以及淹水胁迫下植株的能量代谢情况,初步得出XC与FC都具有一定的耐淹性,且XC较FC具更耐深淹的能力,表明狗牙根作为禾本科植物遗传上具有一定的耐淹性,自然消落带狗牙根因长期生长于水淹胁迫环境,耐淹能力得到了进一步强化。从狗牙根对深淹胁迫的生理响应上,证明狗牙根是宜用于三峡水库消落带植被恢复的物种。更多还原

【Abstract】 A submergence experiment was conducted on Bermudagrasses originally distributed in the water-level-fluctuation zone(XC) and non-water-level-fluctuation zone(FC) of the Three Gorges Reservoir Area.Six treatments with respective submerged depth of 0,1,2,5,10,15m were carried out to investigate the physiological responses of Bermudagrasses.The results indicated that:①Malondialdehyde(MDA) content increased significantly with the increase of submergence depth,,indicating that Bermudagrass suffered the damage of membrane lipid peroxidation under the submergence condition;.②The activities of superoxide dismutase(SOD),peroxide(POD),glutathione reductase(GR) and alcohol dehydrogenase(ADH) in the roots of Bermudagrass were higher than that of un-submerged control.The maximum of POD,SOD and GR activities of XC appeared at 5 meters in submergence depth,and FC at 2 meters.There were relative higher soluble sugar and starch contents by the submergence treatment.③Bermudagrasses originally growing in the natural water-level-fluctuation zone(XC) could endure much deeper submergence than FC by the characteristics of antioxidative enzymatic activities,ADH activity and energy metabolism.The results implies that Bermudagrass has submergence-tolerant instinct,and the submergence-tolerant ability of XC was strengthened by the long-time periodic submergence in its natural habitats.Bermudagrass could be a promising species for revegetation of the water-level-fluctuation zone in the Three Gorges Reservoir Area.更多还原