Analysis of the Triticum aestivum L. genetic diversity induced by the chemical mutagen phosphemide

Currently, climate change and growing demand for food necessitate effective methods for crop improvement. Induced mutagenesis is a promising tool to create breeding material. This work, for the first time, established the potential of the chemical mutagen phosphemide on spring soft wheat. Particularly, it was revealed that seed treatment with an aqueous solution of the mutagen in optimal concentrations effectively increases genetic variability to select economically valuable forms. Our goal was to increase the genetic diversity of spring bread wheat ( Triticum aestivum L.) using the chemical mutagen phosphemide and to determine the biological potential of mutants (M5, M6) based on the variability of morphological and productive traits under the conditions of the Northern Trans-Urals. A total of 29 spring soft wheat samples selected from mutant populations of two cultivars, Cara and Skant 3, from a hybrid (Cara × Skant 3), as well as three control cultivars, the Tyumenskaya 25, Tyumenskaya 29, Novosibirskaya 31 were involved in the study. Mutant samples were generated using the chemical mutagen phosphemide. The seeds were treated with a 0.002 and 0.01 % phosphemide aqueous solution for 3 hours. Identification of mutations and testing their stability were carried out in the second (M2) and third (M3) generations. Here, we submit data for M5 and M6 mutants grown under contrasting meteorological conditions in 2021-2022. Sowing, observations, records, description of morphological characteristics and biological properties of plants were carried out at the experimental site of the biological station of the Tyumen State University “Lake Kuchak” (Nizhnetavdinsky District of Tyumen Province). Electrophoretic analysis of gliadins was carried out in caryopsis of the 2021 harvest (M5). Based on grain electrophoretic analysis of the original and mutant plants, genetic formulas of gliadin were compiled, and the frequency of gliadin coding loci alleles ( Gli ) was determined. In field tests, significant differences occurred between genotypes in quantitative traits, e.g., plant height, linear dimensions and area of the flag leaf, number of productive stem per 1 m2, ear length, grain number and weight per ear. Correlation analysis revealed that the strength of the relationship between yield and other traits depends on the meteorological conditions of the growing season. The dependence of grain yield on the number of plants ( r = 0.71, p 2, on plant height ( r = 0.82, p 0.05), and the number of grains per ear ( r = 0.73, p 2 for the best mutants, and 355.0-424.5 g/m2 for the standard cultivars. Thus, the adaptation potential of spring soft wheat in the Northern Trans-Urals extreme conditions can be increased due to genetic variability of mutant populations. The biological effect of the chemical mutagen phosphemide has been proven to induce beneficial mutations in T. aestivum . Therefore, combination of mutational and recombination variability is effective in increasing genetic diversity.