Detection of Cytogenetic and Genotoxic Effects of Gamma Radiation on M-1 Generation of Three Varieties of Triticum Aestivum L.

Abstract

The effects of (60)Cobalt (Co-60) gamma radiation on cell division and chromosomal structure in M1 generations of three varieties (NKU Lider, Bezostaja and GK Beke's) of Triticum aestivum L. genotypes were determined in this study. To understand and compare the tolerance of on three bread wheat varieties to gamma radiation (100, 200 and 300Gy), the frequency of mitotic index, phase indices and genotoxicity rate were scored and statistically interpreted under irradiated and unirradiated conditions, respectively. In parallel with the increasing radiation dose, mean mitotic index rate decreased in NKU Lider and GK Beke's genotypes. 100Gy Co-60 gamma radiation application of NKU Lider was the most powerful genotype to increase mitotic activity as compared to other genotypes. However; depending on increasing dose of gamma radiation, cell division decreased in all studied genotypes except 200Gy application of Bezostaja genotype. Moreover, genotoxicity index of M1 generation in NKU Lider genotype was decreased in all studied radiation doses with the increasing dose of Co-60. Furthermore, three different variety of T. aestivum L. seeds treated with different doses of Co-60 gamma radiation showed many aberrant chromosomes such as disorderly prophase, stickiness, uncoiling chromosomes, disrupted equatorial plate, fragment, micronucleus, alignment anaphase, fault polarization, anaphase and telophase bridges, lagging chromosomes and stickiness in all mitotic phases. Consequently, the results suggest that gamma radiation effects are specific to the radiation dose and species, and even show different responses in different varieties of the same species.