论文部分内容阅读
采用水培法,研究重金属铅和镉及其复合胁迫对溪荪(Iris sanguine)生理特性的影响。结果表明,在500mg/L铅和500mg/L铅+25 mg/L镉复合胁迫下,溪荪的叶绿素a、叶绿素b和类胡萝卜素含量增加,其中,叶绿素a含量增加显著(p<0.05);在25 mg/L镉胁迫下,溪荪的叶绿素a、叶绿素b和类胡萝卜素含量均减少,其中叶绿素a含量减少显著(p<0.05);25 mg/L镉胁迫增大了溪荪地上部分细胞膜的透性,比对照升高了27%,并使丙二醛含量增加到对照的1.19倍;在500mg/L铅胁迫下,丙二醛含量有所上升,但与对照相比差异不显著,说明在该实验浓度下,溪荪对铅的耐性比对镉的耐性强;在500mg/L铅+25 mg/L镉复合胁迫下,无论溪荪地上部分(叶片)还是地下部分(根茎和根)的丙二醛含量都明显增加,说明复合胁迫给溪荪细胞膜带来很大的伤害;铅和镉胁迫对溪荪过氧化物酶(POD)和超氧化物歧化酶(SOD)活性的影响相似,所有污染处理都对溪荪的地下部分酶活性起明显的促进作用,而对溪荪地上部分的酶活性有明显抑制作用。过氧化物酶和超氧化物歧化酶活性在溪荪耐铅和镉胁迫中起到了非常重要的作用。
Hydroponics was used to study the effects of heavy metals Pb and Cd and their combined stresses on physiological characteristics of Iris sanguine. The results showed that the contents of chlorophyll a, chlorophyll b and carotenoids increased, and the content of chlorophyll a increased significantly (p <0.05) under combined stress of 500 mg / L lead and 500 mg / L lead + 25 mg / Chlorophyll a, chlorophyll b and carotenoid contents of Xixun were reduced under 25 mg / L Cd stress, and the content of chlorophyll a decreased significantly (p <0.05); Under 25 mg / L Cd stress, the contents of chlorophyll a, The permeability of some cell membranes was increased by 27% compared with the control, and the content of MDA was 1.19 times that of the control. The MDA content increased under the lead stress of 500mg / L, but the difference was not significant compared with the control Significantly, indicating that the tolerance of Xunseng to Pb was stronger than that of Cd under the experimental concentration. Under 500 mg / L Pb + 25 mg / L Cd combined stress, both the aerial part (leaf) and the underground part And root) increased significantly, which indicated that composite stress caused great damage to the cell membrane of C. angustifolia. The effects of lead and cadmium stress on the activities of peroxidase (POD) and superoxide dismutase (SOD) , All the pollution treatments obviously promoted the underground enzyme activities of broodstock, while the enzyme activities of the aboveground parts of broodstock Significantly inhibited. Peroxidase and superoxide dismutase activities play a very important role in the tolerance of Lead Xun to Pb and Cd.