Instituto de Investigaciones Químico Biológicas, Universidad Michoacana (UMSNH), Ciudad Universitaria, Morelia, C.P. 58060, Michoacán, Mexico.
N Biotechnol. 2011 Dec 15;29(1):156-64. doi: 10.1016/j.nbt.2011.05.009. Epub 2011 Jun 1.
Phytoremediation is an environmental biotechnology that seeks to remediate pollution caused by bioaccumulative toxins like copper (Cu). Symbiotic mycorrhizal associations can increase the uptake and delivery of low mobility nutrients and micronutrients to the host plant because they solubilize these substances and increase their catchment area. To analyze the effect of mycorrhizae on the phytoaccumulation of Cu, we studied their ability to solubilize Cu(II) and enhance its absorption by the plant Tagetes erecta L. colonized with the arbuscular mycorrhizal fungus Glomus intraradices. Plants were grown for nine weeks in a growth chamber under controlled conditions of temperature, relative humidity and photoperiod. Cu was added in the insoluble form of CuO to simulate the insoluble Cu-O affixed species in soil. The biotic and abiotic parameters of colonization, foliar area, biomass and the pH of leachates were determined as functions of the Cu concentration that was measured in the roots, shoots and leachates by AAS. The results of Cu absorption showed that the colonized plants accumulated more Cu in the roots as well as the whole plant and that both the colonized and non-colonized plants displayed the typical behavior of Cu excluders. Mycorrhizal colonization of the roots resulted in a proliferation of vesicles and this was observed to scale with root tissue Cu concentrations. Also, the G. intraradices-T. erecta system displayed a higher resistance to the toxicity induced by Cu while nonetheless improving the indices of phytoaccumulative yields. These results suggest that G. intraradices possibly accumulates Cu in its vesicles thereby enhancing the Cu tolerance of T. erecta even while increasing root Cu accumulation. The parameters of bioconcentration factor and translocation factor measured in this work suggest that the system T. erecta-G. intraradices can potentially phytostabilize Cu in contaminated soils.
植物修复是一种环境生物技术，旨在修复由生物累积毒素（如铜（Cu））引起的污染。共生菌根关联可以增加低流动性养分和微量元素向宿主植物的吸收和输送，因为它们可以溶解这些物质并增加它们的集水区。为了分析菌根对 Cu 植物积累的影响，我们研究了它们溶解 Cu(II)的能力，并增强了植物菊科万寿菊与丛枝菌根真菌 Glomus intraradices 共生根的吸收能力。植物在温度、相对湿度和光周期得到控制的生长室中生长了九周。Cu 以 CuO 的不溶性形式添加，以模拟土壤中不溶性 Cu-O 固定物种。通过 AAS 测定了生物和非生物参数的定植、叶面积、生物量和淋出液的 pH 值，作为根系、茎和淋出液中 Cu 浓度的函数。Cu 吸收的结果表明，定植植物在根系和整株植物中积累了更多的 Cu，而且定植和非定植植物都表现出 Cu 排斥者的典型行为。根的菌根定植导致了泡囊的增殖，并且观察到泡囊的增殖与根组织的 Cu 浓度成比例。此外，G. intraradices-T. erecta 系统表现出对 Cu 诱导毒性的更高抗性，同时提高了植物积累的产量指数。这些结果表明，G. intraradices 可能在其泡囊中积累 Cu，从而增强了 T. erecta 的 Cu 耐受性，同时增加了根 Cu 的积累。在这项工作中测量的生物浓缩因子和转运因子的参数表明，T. erecta-G. intraradices 系统有可能在污染土壤中固定 Cu。
