Search for genotypes resistant to Cercospora (Cercospora beticola Sacc.) in multigerm breeding materials of sugar beet

Abstract

In sugar beet cultivation, one of the main factors causing a significant drop in size and yield quality is the infection of plant leaves by the fungus Cercospora beticola Sacc. The main aim of the work was to identify inbred lines of sugar beet with genes of resistance to this pathogen. The research and selection works were carried out in multigerm breeding materials type 2xZN with a different degree of homozygosity. For the study, 36 genotypes of the S1 generation and 34 genotypes of the S2 generation were selected as well as 1 standard (Andante) variety with an increased level of fungal resistance. The sensitivity of materials to infection of C. beticola was assessed using a laboratory method (in vitro test). After twice selection a high stabilization of resistance was found within the examined progeny and a clear differentiation between the progeny of the S1 and S2 generation. The average number of spots on 10 leaf discs in the studied 9 progeny of S1 generation was from 10.50 to 31.04, and in 11 progeny of S2 generation from 6.30 to 28.49 using infection under optimal conditions for fungal growth. The wide range of variability that occurred in the tested materials made it possible to select 9 genotypes of the S1 generation and the 11 S2 generation with a high level of resistance to the C. beticola and high cultivation value.