VON Frenckell-Insam Beatrix A K, Hutchinson Thomas C
Department of Botany and Institute of Environmental Studies, University of Toronto, Toronto, Ontario, Canada M5S-1A1.
New Phytol. 1993 Nov;125(3):547-553. doi: 10.1111/j.1469-8137.1993.tb03902.x.
The occurrence of co-tolerance to four heavy metals was investigated among seedlings selected from three different non-tolerant Canadian and German Deschampsia cespitosa (L.) Beauv. populations. Plants selected following screening of seedlings in solution containing Ni or Zn ions, subsequently showed enhanced tolerance to Ni and Zn, respectively. 'Nickel screened' seedlings exhibited no increased tolerance to Zn.'Zinc screened' seedlings, in contrast, had somewhat elevated tolerance to Ni in two of the three populations tested (Elm and Cypress Lake). Thus, co-tolerance may be a population-specific rather than a species-specific response. Individual Elm plants screened for Ni response did not have elevated Zn tolerance, whereas'Zn screened' seedlings did show elevated Ni tolerance. This confirms the result from the population tolerance tests. We conclude that co-tolerance is not a reciprocal process. While the selection for one metal may confer elevated tolerance to a second, selection for the second may not confer tolerance to the first.
在从三个不同的对重金属不具有耐受性的加拿大和德国苔草（Deschampsia cespitosa (L.) Beauv.）种群中挑选出的幼苗中，研究了对四种重金属的共同耐受性。在含有镍或锌离子的溶液中筛选幼苗后挑选出的植株，随后分别表现出对镍和锌的耐受性增强。“经镍筛选”的幼苗对锌的耐受性没有增加。相比之下，“经锌筛选”的幼苗在测试的三个种群（埃尔姆和柏树林湖）中的两个种群中对镍的耐受性有所提高。因此，共同耐受性可能是种群特异性而非物种特异性的反应。筛选出对镍有反应的单个埃尔姆植株对锌的耐受性没有提高，而“经锌筛选”的幼苗确实表现出对镍的耐受性提高。这证实了种群耐受性测试的结果。我们得出结论，共同耐受性不是一个相互的过程。虽然对一种金属的选择可能会赋予对另一种金属更高的耐受性，但对第二种金属的选择可能不会赋予对第一种金属的耐受性。
