ABSTRACT

This work aims to assess growth, physiology, and metal uptake response of Brachiaria mutica and Leptochloa fusca under different contamination levels of Cd (10 and 50 mg kg⁻¹) and Pb (50 and 250 mg kg⁻¹) stress. Results of pot trial showed increasing metal concentration affected B. mutica more as compared to L. fusca. In B. mutica metal stress substantially reduced shoot dry biomass, root dry biomass, total chlorophylls, and carotenoids contents by 89%, 85%, 65%, and 61%, respectively, while enhanced the SOD activity up to 62 U min⁻¹ g⁻¹ FW. L. fusca showed better growth, chlorophylls and carotenoid contents, SOD activity (up to 79 U min⁻¹ g⁻¹ FW), shoot metal uptake potential (Cd 110 µg pot⁻¹, Pb 91.57 µg pot⁻¹), and root metal concentration (Cd 126 mg kg⁻¹ dm, Pb 117 mg kg⁻¹ dm) compared to B. mutica under Pb and Cd stress. While both grass species showed metal translocation factor less than unity under all levels of metal stress. Keeping in view the above results, it is concluded that L. fusca having better growth and physiology with TF < 1 could be used for phytostabilization of Pb and Cd to reclaim the soil having moderate to lower levels of contamination.

摘要

这项工作旨在评估在Cd（10和50 mg kg ^-1）和Pb（50和250 mg kg ^-1）胁迫的不同污染水平下，Brachiaria mutica和Leptochloa fusca的生长，生理和金属吸收响应。盆栽试验结果表明，与富镰孢菌（L. fusca）相比，金属浓度增加对变形杆菌的影响更大。在B. mutica中，金属胁迫分别使茎干生物量，根干生物量，总叶绿素和类胡萝卜素含量分别减少了89％，85％，65％和61％，同时提高了SOD活性，最高可达62 U min ^-1  g ^-1 FW。福斯卡表现出更好的生长，叶绿素和类胡萝卜素含量，SOD活性（高达79 U min ^-1  g ^-1 FW），芽金属吸收势（Cd 110 µg锅^-1，Pb 91.57 µg锅^-1）和根金属浓度（ Cd 126 mg kg ^-1 dm，Pb 117 mg kg ^-1 dm）与B. mutica在Pb和Cd胁迫下相比 虽然两种草种在所有水平的金属胁迫下均表现出小于1的金属转运因子。考虑到以上结果，可以得出结论，具有更好的生长和生理学且TF <1的富氏乳杆菌可用于Pb和Cd的植物稳定化，以恢复污染程度中等至较低的土壤。