MODELING THE PHYTOTOXICITY OF ALUMINUM, CADMIUM, COPPER, MANGANESE, NICKEL, AND ZINC USING THE WEIBULL FREQUENCY-DISTRIBUTION
MODELING THE PHYTOTOXICITY OF ALUMINUM, CADMIUM, COPPER, MANGANESE, NICKEL, AND ZINC USING THE WEIBULL FREQUENCY-DISTRIBUTION
复制标题
DOI：
10.1139/b91-049
复制
发表时间：
1991-02-01
期刊：
影响因子：
--
通讯作者：
DALE, MRT
中科院分区：
文献类型：
--
作者：
TAYLOR, GJ;STADT, KJ;DALE, MRT
采用Weibull频率分布模型，研究了铝、镉、铜、锰、镍和锌胁迫对小麦根系生长的影响。 改良威布尔函数是一种连续的非线性数学函数，可直接估计几个重要的生物学参数，包括最大生长、最小生长、生长反应、毒性阈值和最大单位毒性。 使用标准非线性回归技术将该函数拟合到实验数据。 尽管观察到的剂量反应特征在金属之间存在差异，但Weibull函数提供了每种测试金属的紧密拟合（0.96小于或等于R2小于或等于0.99）。 最大单位毒性的估算表明，镉对T.普通小麦（152%生长减少（GR）/（μ-mol.L）），其次是铜（19.0%GR/（μ-mol.L））、镍（3.9%GR/（μ-mol.L））、铝（1.3%GR/（μ-mol.L））、锌（0.5%GR/（μ-mol.L））和锰（0.2%GR/（μ-mol.L））。 估计的毒性阈值也表明，镉是最有毒的。 镉显示出金属损伤的最低阈值（0.02 μ M），其次是铜（3.4 μ M）、镍（11 μ M）、铝（18 μ M）、锰（37 μ M）和锌（45 μ M）。 锰和锌的相对位置的移动表明，单位毒性和毒性阈值可能是独立的措施，植物对金属胁迫的反应。 这些实验清楚地证明了威布尔函数在模拟植物对金属胁迫的反应中的实用性。 此外，该功能的能力，以模拟初级生长数据直接提供了一个合适的技术，植物毒性金属之间的潜在相互作用的调查。
The toxic effects of aluminum, cadmium, copper, manganese, nickel, and zinc stress on root growth of Triticum aestivum were modelled using a modified version of the Weibull frequency distribution. The modified Weibull function is a continuous, nonlinear mathematical function that provides direct estimates of several important biological parameters, including maximum growth, minimum growth, growth response, toxicity threshold, and maximum unit toxicity. The function was fit to experimental data using standard nonlinear regression techniques. Despite variation among metals in the characteristics of observed dose responses, the Weibull function provided a close fit of each of the metals tested (0.96 less-than-or-equal-to R2 less-than-or-equal-to 0.99). Estimates of maximum unit toxicities indicated that cadmium was most toxic to T. aestivum (152% growth reduction (GR)/(mu-mol.L)), followed by copper (19.0% GR/(mu-mol.L)), nickel (3.9% GR/(mu-mol.L)), aluminum (1.3% GR/(mu-mol.L)), zinc (0.5% GR/(mu-mol.L)), and manganese (0.2% GR/(mu-mol.L)). Estimated toxicity thresholds also indicated that cadmium was most toxic. Cadmium showed the lowest threshold for metal injury (0.02-mu-M), followed by copper (3.4-mu-M), nickel (11-mu-M), aluminum (18-mu-M), manganese (37-mu-M), and zinc (45-mu-M). The shift in the relative position of Mn and Zn suggests that unit toxicity and the toxicity threshold may be independent measures of the response of plants to metal stress. These experiments clearly demonstrate the utility of the Weibull function in modelling the response of plants to metal stress. Furthermore, the ability of the function to model primary growth data directly provides a suitable technique for investigation of potential interactions between phytotoxic metals.