MARKER-BASED SCREENING OF INTERNATIONAL AND LOCAL POTATO GERMPLASM ACROSS KEY AGRONOMIC TRAITS
Abstract
The development of competitive potato cultivars adapted to local production conditions and specific end uses in Kazakhstan requires efficient selection of parental material. Molecular markers can be used to screen breeding germplasm for more than one economically important trait. A total of 32 potato genotypes (22 International Potato Center (CIP) breeding lines and 10 cultivars cultivated in Kazakhstan) were characterized using 30 SCAR and gene-specific PCR markers related to tuber shape, starch metabolism, maturity, flesh colour and late blight resistance. The informativeness of markers was determined by the Polymorphism Information Content (PIC) and the genetic similarity of the genotypes was estimated by the Jaccard coefficient, the UPGMA cluster analysis and Principal Coordinates Analysis (PCoA). 73.3% (22) of the markers were polymorphic in the studied collection. The highest PIC values were observed for StUCP and BLB1 (0.498 each), followed by AGPaseS (0.492), SCAR14S6 (0.469), Rpi-ber1-Q133 and EDN61 (0.451 each), SCAR20S2 (0.430), and SCAR26S35 (0.404). The UPGMA analysis clustered the collection into two main groups, with all cultivars in one group while CIP lines were divided among the two groups. Starch-metabolism markers, tuber-shape markers, and the BLB1 resistance-associated marker were the main markers associated with the separation. Several useful starch- and resistance-associated markers were found on cultivars, while complementary marker diversity such as the EDN61-associated resistance locus was found from the CIP lines. The results suggest that the use of selected cultivars with CIP breeding lines may offer parental combinations that contain desirable quality-related traits and complementary resistance-associated diversity. Marker-based screening can thus complement more efficient parental selection, but phenotypic evaluation is still required to confirm expression of the trait in the field.