Abstract
The principal concern of our study, which is carried out in microcosmic conditions, is focused on removing some plant toxic heavy metals such as Ni, Se, Zn, Pb, Cd, Cr and Cu from soil by using Mimosa pigra plant, as well as the measuring the effect of these harmful elements on some morphological characters of seedlings such as length, number of leaves, fresh weigh, dry weigh and chlorophyll A and B. The investigation also evaluates the effect of Acacia. nilotica methanolic extract (ANME) on heavy metals removing process. Seedlings of M. pigra were subjected to two treatments; first by two different concentrations of heavy metals solutions, the second by adding of ANME. Atomic absorption analysis of seedlings exhibited that M. pigra seedlings had a good ability to remove Ni (20 ppm), Zn (80.01 ppm), Cr (8.82 ppm), Cd (17.57 ppm) and Cu (223.75), especially in case of seedlings treated with high concentrations of heavy metals, while accumulation of Se and Pb was not affected by increasing the concentration of elements. Addition of ANME enhanced the accumulation of Ni (35.1 ppm), Cr (11ppm), and Se (186.24 ppm). Accumulation of heavy metals resulted in reduction in length, number of leaves, fresh weight, dry weight and chlorophyll a and b content of M. pigra seedlings. Statistical data analysis was carried out using One-way analysis of variance (ANOVA).