蕹菜典型品种中Cd、Pb、Cr、Ni等重金属含量及其相关性

摘要

目的:蕹菜( Ipomoea aquatica Forsk.)Cd(镉)积累典型品种对Cd、Pb(铅)、Cr(铬)、Ni(镍)等多种重金属的吸收积累及相互关系.方法:采用盆栽试验,分析4个蕹菜Cd积累典型品种在6种土壤上的两茬茎叶及根Cd、Pb、Cr、Ni含量及相关性.结果:①品种和土壤对供试蕹菜典型品种Cd含量的效应均达显著水平(P＜0.05),对Pb、Cr和Ni含量的效应因重金属、收获时期及部位而不同,二者对Cd、Pb含量具一定的交互效应.②两茬茎叶Cd含量平均值均为T308＞GDB＞QLB＞QLQ,根Cd平均含量高于茎叶Cd平均含量；除Cr外,根Pb和Ni平均含量均高于茎叶.③Cd、Pb、Cr、Ni含量呈现复杂的相关关系.茎叶Cd含量与Pb含量正相关,且第一茬相关性极显著(P＜0.01)；Pb含量与Ni含量相关关系明显,第一茬茎叶、根Pb含量与Ni含量的正相关达到显著(P＜0.05)或极显著水平(P＜0.01),但第二茬茎叶Pb含量与Ni含量却显著负相关(P＜0.05)；Pb含量与Cr含量的相关性仅第一茬茎叶显著(P＜0.05)；Cr含量与Ni含量的相关性仅第二茬茎叶达极显著水平(P＜0.01).结论:蕹菜典型品种对Cd、Pb、Cr、Ni的吸收积累存在协同和拮抗两种作用.%Objective: To investigate the interaction of Cd, Pb, Cr and Ni for uptake and accumulation in water spinach (Ipomoea aquatica Forsk.) typical cultivars with different Cd accumulation abilities. Methods: A pot experiment was conducted to study the concentrations of Cd, Pb, Cr and Ni in shoots and roots of four water spinach typical cultivars under six soils, and the correlative interaction of Cd, Pb, Cr and Ni concentrations. Results: 1. The effects of cultivar and soil on Cd concentrations in the tested cultivars were always significant (P < 0.05), and those on Pb, Cr and Ni concentrations were different among heavy metals, harvests and organs. The interaction of cultivar and soil affected Cd and Pb concentrations significantly (P < 0.05). 2. Average shoot Cd concentrations in first and second harvests were T308 > GDB > QLB > QLQ. Average Cd concentrations in root were higher than those in shoot. Expect Cr, average Pb and Ni concentrations in root were higher than those in shoot. 3. Complicated interaction were observed among Cd, Pb, Cr and Ni concentrations. Cd concentrations were significantly and positively correlated with Pb concentrations in shoot of the first harvest (P < 0.01). Pb concentrations were significantly and positively correlated with Ni concentrations in root and shoot of the first harvest (P < 0.05), but significantly and negatively correlated in shoot of the second harvest (P < 0.05). Pb concentrations were significantly and positively correlated with Cr concentrations in shoot of the first harvest (P < 0.05). Cr concentrations were significantly and positively correlated with Ni concentrations in shoot of the second harvest (P < 0.01). Conclusion: The interaction of Cd, Pb, Cr and Ni for uptake and accumulation in water spinach typical cultivars included antagonism and synergism.