The cytotgenetic and genotoxic potentials of aqueous extract of Peganum harmala L. seeds were evaluated in the M2 generation of Vicia faba plants, following parent plants seeds exposure to different concentrations 12.5, 25, 50, and 100% of the aqueous extract for 3, 6, 12 and 24 hr., using three endpoints i.e. cytogenetic abnormalities, seed proteins and DNA simple sequence repeats (SSRs) fingerprinting. Chromosomal abnormalities were observed in the M2 plant roots due to actions on the spindle apparatus leading to c-mitosis, vagrant chromosomes and laggards, sticky chromosomes and anaphase-telophase bridges, disordered anaphase, as well as micronuclei in interphase cells. Some of these abnormalities may result in stable structural modifications that are transmissible across generations. The SDS-PAGE analysis showed distinctive qualitative and quantitative alterations in number of polypeptide bands, molecular weights, and intensities of polypeptide bands. The production of different proteins entails a vast array of DNA binding proteins that act in various combinations to either activate or repress gene expression. Twenty-five SSR alleles were detected in the control and M2 plants using 11 SSR primer pairs. The number of alleles in the control plants was much lower than the number of alleles in the M2 plants. The changes in SSR fingerprinting might be connected to structural rearrangements in the chromosomes and DNA caused by different types of DNA damages. Such changes validate the mutagenic potential that was indicated by abundance of chromosomal abnormalities and alterations in the SDS-PAGE analysis of seed proteins.
Key words: Cytogenetic, Genotoxic, Peganum harmala, PAGE, SSR, Vicia faba
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