Cytogenetic variability among modern winter wheat varieties

Abstract

Chemical supermutagens of the alkyl group can significantly increase the mutation rate compared to others, such as ionizing radiation. The frequency of mutations can be 1.5-2 times higher than that of related substances. Purpose. To investigate the differences in cytogenetic variability according to the frequencies and spectra of chromosomal aberrations in winter wheat cells depending on the concentration and variety, to show the main parameters by which the process of variability at the cellular level of the organization can be modeled. Methods. Seeds of 4 varieties of winter wheat Perspektyva Odeska, Sonata Poltavska, Shpalivka and MIP Lada were treated with an aqueous solution of DAB (1,4-bisdiazoacetylbutane) at concentrations of 0.1%, 0.2%, 0.3%. The analysis of chromosomal aberrations at the late stage of metaphase and early anaphase was carried out by the method of light microscopy. Results. The influence of the variety was significant only on the induction of complex aberrations, but the increase in the concentration of DAB absorbed significantly and reliably for all types of changes. According to the indicator of the total frequency of aberrations, the variety Sonata Poltavska was significantly different, which turned out to be more tolerant (lower frequency of aberrations). A pairwise comparison showed for the number of fragments that when changing between individual concentrations, the difference was always reliable, except from DAB 0.2% to DAB 0.3% for the variety Perspektyva Odeska. In the case of bridges, the first concentration had a significant effect in comparison with the control only for varieties Shpalyvka and MIP Lada. For other types of chromosomal rearrangements, we find that all variants have no statistically significant difference with the control, except for the variety Sonata Poltavska, which has no difference between DAB 0.1 and DAB 0.2%. The transition from DAB 0.2 to DAB 0.3% is unreliable only for the Perspektyva Odeska. When inducing complex aberrations, there are statistically significant differences for all variants, except for the transition between DAB concentrations of 0.1% and 0.2% in the variety Sonata Poltavska. The analysis of centroid distances showed the impracticality of using DAB concentrations of 0.1 and 0.2% at the same time. Findings. The key is the indicator of multiple (complex) reconstructions. The variety Sonata Poltavska showed a higher genetic affinity to the effect of DAB due to a higher tolerance to adverse consequences, especially in the indicators of the overall frequency of rearrangements, the number of fragments, other types and complex aberrations. The applied concentrations should be attributed to the range of conditionally moderate. It is impractical to use DAB 0.1 and DAB 0.2% concentrations at the same time.