Relationship between sterility in M1 generation and frequency and spectrum of chlorophyll mutants in M2 generation after treatment with sodium azide in winter barley varieties

Boryana Dyulgerova, Nikolay Dyulgerov

Abstract: The aim of the present study was to investigate the relationship between sterility in M1 generation and the frequency and spectrum of chlorophyll mutants in M2 generation after treatment with sodium azide in two varieties of winter barley. The study was conducted at the Institute of Agriculture - Karnobat in two consecutive growing years - 2020-2021 and 2021-2022. It was found that the frequency of chlorophyll mutations in the M2 generation varied significantly between the two studied winter varieties of barley. The variety Imeon had a higher mutability than the variety Monika. The difference in the percentage of chlorophyll mutants between the two years of study in the variety Imeon was statistically significant. The variety Monika showed a significantly higher frequency of chlorophyll mutations in the progenies obtained from fertility classes up to 50% in the M1 generation in both years. In Imeon, in the first year, the highest percentage of chlorophyll mutants was found in the progenies obtained from classes with fertility from 51 to 75%, and in the second year the highest frequency of mutants in the progenies of fertility classes with up to 50%. These results indicate that the selection of spikes with high fertility in the M1 generation can lead to a significant reduction in the mutation frequency in the M2 generation. The spectrum of chlorophyll mutations varies considerably, both between varieties and between years of study. No relationship was found between the spectrum of chlorophyll mutations in the M2 generation and the fertility classes in the M1 generation.

Keywords: chlorophyll mutations; Hordeum vulgare; sodium azide

Date published: 2022-08-16