海南风吹楠对铅、镉胁迫的生长响应及综合评价分析

Growth Response and Comprehensive Evaluation Analysis of Horsfieldia hainanensis under Single Stress of Pb and Cd

以1年生海南风吹楠(Horsfieldia hainanensis)为材料,设置4个铅浓度(250、500、1000、2000mg/kg)和4个镉浓度(10、25、50、100mg/kg),研究铅、镉单一胁迫对海南风吹楠生长的影响。结果表明,在镉、铅单一胁迫下,海南风吹楠的株高增长量、地径增长量、生物量、总根长和总根表面积呈上升趋势,且均在铅浓度为500mg/kg、镉浓度为25mg/kg时达到最大值,随着铅、镉浓度的增加,其各生长指标呈下降趋势;海南风吹楠的生长指标对铅、镉单一胁迫差异显著。综合评价得知,铅浓度为500mg/kg、镉浓度为25mg/kg时苗木质量最佳,能促进海南风吹楠的生长,而高浓度的铅(2000mg/kg)、镉(100mg/kg)则会对其生长产生毒害。

Using Horsfieldia hainanensis as experimental object, effects of single stress of Pb and Cd on growth of H.hainanensis investigated by four were Pb concentrations(250 mg/kg,500 mg/kg,1 000 mg/kg, 2 000 mg/kg) and four Cd concentrations (10 mg/kg,25 mg/kg,50 mg/kg,100 mg/kg). Results showed that height increment,ground diameter increment,biomass,total root length and total root surface aera increased firstly and reached the highest when Pb 500 mg/kg and Cd 25 mg/kg,then decreased with increase of Pb or Cd concentration. Growth indexes of H. hainanensis had significant differences under single stress of Pb and Cd. Comprehensive evaluation showed that seedlings quality was the best in Pb 500 mg/kg and Cd 25 mg/kg which could promote growth of H. hainanensis and high concentration Pb 2000 mg/kg and Cd 100 mg/kg could produce toxicity for seedlings.