‘鲁赫’刺蔷薇对铅、镉及其混合胁迫的生理响应

Physiological Response of Rosa acicularis ‘Luhe'to Lead,Cadmium and Mixed Stresses

以俄罗斯引进的‘鲁赫’刺蔷薇(Rosa acicularis‘Luhe’)为研究对象,通过盆栽试验人工模拟铅、镉、铅+镉混合胁迫环境,检测‘鲁赫’刺蔷薇在铅、镉及铅+镉混合胁迫下的生理指标以及对重金属铅、镉的积累量,分析比较不同年份及不同繁殖方式的‘鲁赫’刺蔷薇对重金属铅、镉的耐受性和富集规律,以期为‘鲁赫’刺蔷薇在北方城市地区的推广栽培提供科学依据。结果表明:1)在持续铅、镉、铅+镉混合胁迫中,不同年份及不同繁殖方式的‘鲁赫’刺蔷薇受到了不同程度的毒害,但通过保护酶升高等方式使其在试验胁迫浓度范围内(Pb<350mg·kg-1,Cd<1.5mg·kg-1)具有很强的抵抗铅、镉及铅+镉混合胁迫的能力,抗性强弱依次为2年生实生苗(B2)>2年生扦插苗(A2)>1年生实生苗(B1)>1年生扦插苗(A1)。2)‘鲁赫’刺蔷薇B2、A2、B1、A1均表现出根部对重金属铅、镉的积累性较强,其次是地上部分;相较于铅而言,镉更易在‘鲁赫’刺蔷薇中富集。3)总体看来,Pb+Cd混合胁迫与相应单一胁迫相比,高浓度胁迫下的拮抗作用更明显,低浓度下协同作用更明显。

Physiological response of Rosa acicularis ‘Luhe’ that was introduced from Russia to artificially simulated lead,cadmium and mixed stresses were studied through a pot experiment.Physiological and biochemical indexes of the rose seedlings which grew up in different years and bred with different methods were analyzed to understand its ability of absorbing and accumulating lead and cadmium.Tolerance and enrichment of the seedlings to lead and cadmium were compared to provide references for the promotion the introduced rose species in some parts of northern China.The results were as follows.1）All the seedlings were poisoned to a certain degree under individual or mixed stresses of the two heavy metals.The seedlings presented strong resistance to the stresses within the range of experimental concentration （Pb〈350 mg·kg -1 ,Cd〈1.5 mg·kg -1 ） by increase the protective enzymes.The order of resistance for the seedlings bred with different methods was biennial seedlings （B2） 〉 biennial cutting seedlings （A2） 〉 annual seedings （B1） 〉 annual cutting seedlings （A1）.2）The roots of B2,A2,A1 and B1 demonstrated stronger accumulation capability to heavy metal than aboveground parts; Cd was more likely to be accumulated in the rose seedlings than Pb. 3） Compared with individual stress,the effect of the antagonism was more obvious under high concentration stress,and the synergistic effect was more obvious under low concentration stress.