Abstract: By using random amplified polymorphic DNA (RAPD) technique, this paper studied the effects of Cd stress on DNA polymorphism in root tip of Vicia faba seedlings. The results showed that after 7 days of 2.5-15 mg Cd·L^-1 stress, the root elongation growth was inhib-ited, and the total soluble protein content in root tip was decreased. A total of six oligonucleotide primers (10 bp) were found to produce unique polymorphic band patterns, and subsequently used to produce 86 bands of 200-2 520 bp in molecular size in the normal root tip of V. faba seedlings. The RAPD profiles showed obvious differences between normal and exposed plantlets, and the change effect was dose-dependent. The genomic template stability was significantly af-fected by Cd pollution, and the DNA polymorphisms detected by RAPD technique could be used as a biomarker for detecting the genotoxic effects of Cd stress on plants.

Key words: Grass, Life form, Germination rates, Ruderals, Disturbance