互花米草对持续淹水胁迫的生理响应

Physiological responses of Spartina alterniflora to long-term waterlogging stress

对互花米草进行了40cm水深的持续淹水胁迫,研究了其生理指标的响应.结果显示,淹水胁迫下,互花米草叶片中可溶性糖含量和叶绿素含量在初期均显著低于对照,随后逐渐积累并高于对照.丙二醛含量在初期显著高于对照,随后与对照组的差异逐渐减小,至生长季末与对照水平相当.过氧化物酶活性在淹水后63d内均高于对照,至生长季末则低于对照,而超氧化物歧化酶活性则始终高于对照.至生长季末,持续淹水胁迫条件下的互花米草生物量低于对照,其形态学上表现为植株矮小、根系变短、节长变短、地下部分所占生物量比重降低.研究结果表明,持续淹水胁迫对互花米草的生理指标产生影响,但互花米草可以通过生理和形态学的响应来适应这种胁迫,因此,必须进一步结合其它物理控制措施进行综合治理.

Effects of waterlogging stress on the physiological and growth responses of Spartina alterniflora and its adaptation mechanisms under long-term waterlogging conditions were studied. The results showed that the contents of soluble sugar and chlorophyll in leaves were lower than those of the control at the beginning of the experiment and then accumulated gradually. The contents of MDA increased remarkably at the beginning and then decreased. The activities of SOD and POD increased at the beginning and decreased subsequently. Under the waterlogging conditions, the height, node length and biomass ratio of underground vs. aboveground were lower than those of the control. The results from this study indicated that waterlogging stress could inhibit the growth of S. alterniflora, but the plant could effectively adapt to the stress by physiological and morphological adjustment. Therefore, waterlogging together with other control measures should be an effective way for controlling the expansion of S. alteruiflora.