Analysis of DNA single-nucleotide polymorphism in maize inbreds with different degrees of sensitivity to head smut (Sporisorium reilianum)

Aim. Single-nucleotide polymorphism analysis of maize inbreds with different rate of sensitivity to the head smut caused by Sporisorium reilianum, assessment of genetic relationships between them, and search for statistically significant associations between SNP markers and phenotypic manifestation of pathogen resistance. Methods. The single-nucleotide polymorphism analysis using BDI-III panel with 384 SNP markers, statistical methods. Results. The SNP analysis of seven maize inbreds with different sensitivity to S. reilianum infection was carried out. The key indicators of single-nucleotide polymorphism markers with BDI-III panel were assessed: the fraction of dimorphic markers was 85.8%, the average minor allele frequency was 0.2984, the fraction of dimorphic markers with the minor allele frequency >0.2 was 68.2%, the average polymorphism information content (PIC) was 0.2770. The main indicators of the maize inbreds were determined by SNP markers. It was established that the average homozygosity of the inbreds was 98.5%, the average gene diversity index was 0.1723, and the average genetic distance was 0.4975. It was found the allelic state of SNP markers of the BDI-III panel — BDI-III-270C and BDI-III-292A, which is characteristic of maize inbreds resistant to head smut, as well as BDI-III-270A and BDI-III-292G for maize inbreds sensitive to head smut. The dendrogram of genetic relationships for the studied maize inbreds was drawn. Conclusions. The presence of statistically significant associations between the allelic state of two SNP markers and the phenotypic manifestation of the maize resistance to head smut was established. The random nature of the location of maize inbreds sensitive to head smut on the dendrogram of genetic relationships was revealed. In the future, the identified single-nucleotide polymorphism markers, which were associated with head smut resistance, will be verified on a larger number of maize genotypes of different origin to confirm the possibility of their practical application.