SSR-MARKERS OF GENES FOR RESISTANCE TO DOWNY MILDEW IN SUNFLOWER

Abstract

One of economically valuable traits of sunflower culture is resistance to the pathogenic fungus – downy mildew ( Plasmopara helianthi Novot.). Stability to the most aggressive pathogen races is controlled by a number of Pl genes, which are groups into several clusters. At present intensive research of marking Pl loci is being carried out. In order to create the system of DNA-markers for selection of sunflower genotypes with certain allele composition of Pl genes molecular-genetic polymorphism of lines-carriers of Pl genes and lines, which do not have resistance genes, by alleles of microsattelite loci, localised on 1, 8, 13 groups of linkage of sunflower genetic map, was studied in the work. 13 lines-differentiators HA-288, RHA-265, RHA-274, DM-2, PM-13, PM-17, 803-I, QHP-1, FT-226 (QHP-1 analogue), HA-R4, HA-R5, HA-335, RHA-419 and lines of Ukrainian selection 108 А and ОС 1029 В were used as the research material. Genotyping of the studied lines by 34 microsattelite loci, localised on 1, 8 and 13 groups of linkage of sunflower genetic map at the distance not more than 10 cM from Pl gene clusters. Marker alleles of microsattelite ORS 328 , which make it possible to identify samples, carrying genetic material, characteristic of the line Pl 6 НА-335 carrier, were detected. Characteristic of the line-donor of gene Pl 8 QHP-1 allele of the size 410 bp of locus ORS 781 , which can be useful in marker selection of recombinants, was detected. Marker alleles by loci ORS 509 , ORS 610 , ORS 1182 , ORS 605 , ORS 675 , ORS 1039, which make it possible to distinguish line RHA-419, the genotype of which has the gene of universal resistance Pl ARG .were determined. Detected were alleles, characteristic of the genotypes of lines-donors of Pl 13 HA-R4 and QHP-1 by loci ORS 1008 and ORS 965-1 . Application of the identified markers of certain Pl genes in marker selection was proposed in order to accelerate targeted selection of samples in the process of creation of new sunflower lines and hybrids.