Effects of Gamma Radiation on Mitosis and Meiosis Anomalies and Agronomic Features in M2 Plants of Vicia faba cv. Saraziri

Abstract

Investigation of aberrations caused by gamma radiation in mitosis and meiosis might be fundamental to elucidate the interaction between radiations and biological systems. To identify the effects of the various doses of gamma radiation (25, 35, 45, 55 Gy) on mitotic and meiotic traits and agronomical features, a field experiment and microscopy assays were conducted on M2 generation of Vicia faba cv. Saraziri. Various types of mitotic and meiotic anomalies including laggard chromosomes, precocious movement of chromosome, anaphase and telophase bridge, chromosome fragments, chromosome stickiness, micronuclei, disturbed anaphase, vagrant chromosomes, the trinucleate status in telophase and tripolar anaphase were observed in root meristem cells and pollen mother cells (PMCs). The meiosis of PMCs showed less sensitivity towards gamma radiation than mitosis of root meristem cells. Among different stages of mitosis and meiosis, the most anomalies in terms of frequency were attributed to anaphase in mitosis and telophase II in meiosis. The recorded data of different anomalies confirmed that the micronuclei in telophase of mitosis and meiosis had the most frequencies in all gamma ray doses. The effects of different doses of gamma rays on agronomic traits including the number of pods per plant, number of seeds per pod, number of seeds per plant, and seed yield per plant were significant and the values decreased as the irradiation dose increased. Moreover, increasing irradiation doses caused a delay in flowering, pod setting, and pod ripening period. The highly negative correlations between mitosis and meiosis anomalies and agronomical traits were reported in this research.