木槿品种对镉胁迫的生理响应及耐镉能力评价

Physiological Response of Hibiscus syriacus Varieties to Cadmium Stress and Evaluation of Cadmium Tolerance

研究镉胁迫对木槿的生理影响,比较木槿品种的镉耐受能力,为镉污染地区的植物材料选择提供依据。以3个木槿品种为材料,采取盆栽控制试验,测定其生长、生理指标,通过隶属函数分析综合比较品种耐镉能力。木槿的株高与地径增长量、叶绿素A+B与可溶性蛋白含量随胁迫浓度增加呈先上升后降低或逐渐降低趋势,而且随时间延长,降低程度不断加强;游离脯氨酸、丙二醛含量、SOD活性随胁迫浓度与胁迫时间增加而逐渐上升,但长时间高浓度胁迫下,不同品种会出现不同程度的下降;隶属函数分析发现品种耐受能力因胁迫浓度有所差异。镉胁迫浓度对木槿生长有低促高抑作用,而且随时间延长出现促进减弱、抑制加强;3个品种中‘红星’的表现最佳,值得推广。

The objective is to study the physiological effects of cadmium stress on Hibiscus syriacus and compare the cadmium tolerance of H.syriacus varieties,so as to provide basis for the selection of plant materials in cadmium polluted areas.Three H.syriacus cultivars were used as materials,and pot experiment was conducted to determine their growth and physiological indexes.Membership function analysis was used to comprehensively compare the cadmium tolerance of varieties.The growth of height and ground diameter,the content of chlorophyll A+B and soluble protein of H.syriacus first increased and then decreased or gradually decreased with the increase of stress concentration,and the degree of decrease gradually increased with the extension of time.Free proline,malondialdehyde content and SOD activity increased gradually with the increase of stress concentration and time,but decreased in different degrees under long-term high concentration stress.The results of membership function analysis showed that the tolerance of varieties varied with the stress concentration.The growth of H.syriacus under Cd stress was promoted by low concentration and inhibited by high concentration,and with the extension of time,the promotion weakened and the inhibition strengthened.In addition,the performance of ‘Hong xing’ is the best,which is worth of promoting.