Rhizobium as a Biological Agent for Preventing Heavy Metal Stress

Abstract

In the present study, Rhizobium was used as soil fertilizer toprevent the stress of lead on growing Pisum sativum. Threeconcentrations of lead were used (50, 100 and 200 ppm.) for theirrigation of growing plants (two times). After sowing, M2 seeds werecollected, then cytological and biochemical studies were carried out.The cytological analysis revealed that soil enriched with Rhizobiumincreased the rate of mitotic division. A significant increase in mitoticindex was detected. The kind of chromosomal abnormalities observedwere; disturbances, stickiness, diagonals, chromosome breakage and c-metaphases. Also, a significant reduction in the percentage ofabnormalities was observed. Biochemical studies included the analysisof M2 seed proteins using SDS-PAGE, isozyme analysis for bothesterase and peroxidase and element analysis of Pb and N.