【摘要】 【目的】通过不同Pb2+对中华常春藤进行胁迫处理,探讨不同浓度Pb2+胁迫对植株的生长性状和生理特性的影响,为中华常春藤的栽培推广以及选择铅高富集植物提供一定理论依据。【方法】以当年生中华常春藤扦插苗为研究对象,对其进行不同浓度Pb(CH3COO)2溶液胁迫处理,并测定各项生长及生理指标。【结果】低浓度铅胁迫下(50、200μmol/L),中华常春藤株高、节间距及茎、叶生物量以及总生物量都显著降低,植物体内MDA含量也显著上升,同时,可溶性蛋白含量、抗氧化酶CAT、POD活性亦显著增加;而高浓度铅胁迫下(400、800μmol/L),植株株高、节间距显著增加,但生物量无显著变化,植株茎段呈现明显徒长现象。同时,植株体内的氧自由基含量、可溶性蛋白含量及抗氧化酶SOD活性亦显著增加。【结论】中华常春藤对铅胁迫具有较强的耐性,可通过激活自身的抗氧化系统及增加可溶性蛋白来抵御铅胁迫下活性氧对其的伤害;此外,低浓度的铅胁迫可使其生长受到抑制,而较高浓度的铅胁迫却会刺激该植物的徒长。更多还原

【Abstract】 [purpose]In order to investigate the effect of lead stress on the seedling growth characteristics of Hedera nepalensis var. sinensis, and the effects on growth and physiological characteristics were studied under lead stress to provide a theoretical base for lead resistant cultivation and the selection of lead-tolerant plants.[Method]H. nepalensis var. sinensis were used as the experiment materials, the growth and physiological characteristics were determined under different concentrations of Pb(CH3 COO)2 treatment groups.[Result]The plant height, internodes’ spacing, stem biomass, leaf biomass and total biomass were significantly decreased under the lower Pb2+ concentration stresses(50, 200 μmol/L), and the MDA content, the soluble protein content, the antioxidant enzyme CAT and POD activities in plant leaves were also increased. While under the higher Pb2+ concentration stresses(400, 800 μmol/L), the plant height and the internodes’ spacing were significantly increased, but the biomass did not changed significantly, the stems appear to be significantly longer; at the same time, the soluble protein content, oxygen free radical content and antioxidant enzyme SOD activity also increased significantly.[Conclusion]This study shows that H. nepalensis var. sinensis has strong tolerance to lead stress and could resist the damage of reactive oxygen under lead stress by activating its antioxidant system and increasing the soluble protein. In addition, the plants will be inhibited to growth by the lower concentration lead stress while be stimulated to excessive growth by the higher concentration lead stress.更多还原