水淹胁迫对虎尾草生理指标的影响

Physiological Responses of Chloris virgata to Different Flooding Stresses

为探究虎尾草在不同滨水环境下的生理响应机制及水淹适应性,研究了虎尾草在不同水深(对照、渍水、部分水淹、全淹)、不同时间(0、5、10、15、20、25、30d)水淹胁迫下,其部分相关生理指标的响应规律及各生理指标间的相关性。结果表明:随着水淹时间的延长,虎尾草根系活力、叶绿素质量分数逐渐下降,虎尾草地下部分较地上部分更先受到水淹胁迫的伤害,且伤害程度更深。丙二醛(MDA)质量摩尔浓度、过氧化物酶活性、过氧化氢酶活性逐渐上升,超氧化物歧化酶活性呈先升后降的趋势;可溶性还原糖质量分数在渍水处理下,变化不显著,在部分水淹及全淹处理下,达到峰值后逐渐稳定;脯氨酸质量分数在渍水及部分水淹处理下,逐渐上升,在全淹处理下,呈先升后降的趋势。渍水、部分水淹及全淹处理各指标相关性达到显著(P<0.05)或极显著(P<0.01)的分别占总数的42.86%、85.71%和60.71%,高于对照组。综上,虎尾草通过提高自身抗氧化酶的活性及渗透调节物质的质量分数,同时增强各生理因子间的联动和协作共同抵御水淹胁迫造成的伤害。虎尾草具有一定的耐水淹能力,可作为滨水地带的备选植物资源。

In order to explore the physiological response mechanism and adaptability in flooding stresses of Chloris virgate , we studied the response laws of physiological indices and correlation between indices of C. virgata under different water depths (control, root-merged, part-merged, submerged) and different time (0, 5, 10, 15, 20, 25, 30 d) water logging. With the extension of flooding time, the root activity and chlorophyll content of C. virgata decreased gradually, the underground portion of C. virgata was hurt more seriously and earlier than the aerial parts. Contrarily, the malondialdehyde content, peroxidase activity and catalase activity gradually increased, compared to control group, the activity of superoxide dismutase increased first and then decreased, under root-merged, the content of soluble reducing sugar did not change significantly, however, the content of soluble reducing sugar reached peak values and then gradually stabilized under part-merged and submerged, the proline content increased gradually when root-merged and part-merged, meanwhile, the content of proline increased first and then decreased in submerged water. The correlations of indicators among root-merged, part-merged and submerged were significant ( P <0.05) or extremely significant ( P <0.01) accounting for 42.86%, 85.71% and 60.71% of the total, higher than control. Therefore, the antioxidant enzyme activities and osmotic adjustment substances are improved and adjusted, moreover, the linkage and collaboration between physiological factors is enhanced, of C. virgate to resist water logging together. C. virgate has a certain waterlogging tolerance, and can be used as alternative plant resources in waterfront.