CYTOGENETIC STUDY OF TOXICITY AND MUTATION VARIABILITY INDUCED BY CHEMICAL MUTAGENS IN SEEDS OF LOLIUM PERENNE L., AGROPYRUM CRISTATUM L. AND MEDICAGO SATIVA L.

摘要

Results of cytogenetic analysis of mutation variability induced by treatment of seeds of forage crops Medicago saliva L., Lolium perenne L. and Agropyrum cristatum L. with alkylating mutagens DMS, DES and mutagens NMU and NEU are presented. The frequency and spectrum of chromosome aberrations with recording of the aberration types in root tips at first mitosis after mutagenic treatment of seeds in connection with the study of the influence of chemical mutagen (CM) at ontogenesis at M, were analyzed with anaphase analysis. The genotype reaction to CMs with an intermediate solvent DO and the specificity of the different CMs were studied. It was found that in lucerne the dialkyl sulphates (DMS and DES) had the highest mutagenic efficiency and in wheat-grass and ryegrass — the supermutagens (NMU and NEU). By analysis of the spectrum of the chromosome aberrations it was found that the aberrations of chromatid origin (single bridges and fragments) prevailed, the relative proportion of the chromatid bridges being greater. The criteria of CM toxicity were germinating energy and ger-minability. This study prepared breeding research directed to introduction of mutation breeding into forage crops.