Nucleotide substitutions in the resistance gene to root-knot nematodes in sugar beet

Abstract

Here we are testing the specific primers NEM06FWD2/NEM06REV2 and nem06FWD1/ nem06REV1 for the R6m-1 resistance gene to root-knot nematodes Meloidogyne spp. in breeding samples of sugar beet. Sugar beet plants of domestic and foreign breeding lines were the object of the study. To identify the relationship between R6m-1 gene, which is localized on the chromosome 1 and controls the stable level of the kinase activity signal, with sugar beet resistance to phytopathogens, PCR-analysis of 10 sugar beet samples were carried out using 2 pairs of molecular genetic markers. DNA amplification revealed a fragments ~500 bp and ~100 bp in length and as a result of sequencing of nucleotide sequences of R6m-1 gene region with subsequent alignment by Geneious Prime program, 3 single nucleotide substitutions (A/G, G/C, and G/A) in the resistant MS11018 genotype and one nucleotide substitution (A/G) and 3 deletions in a foreign hybrid Humber were identified. It can be assumed that these SNPs can form resistance by amino acid substitutions in the polypeptide chain. Finally, possibility to differentiate homozygous and heterozygous genotypes for this allele was shown.