Association Study of SNPs Markers to Traits Linked to Drought Stress Tolerance in Potato

Abstract

Potato (Solanum tuberosum L.) is the third most important food crop in the world and its production is constantly threatened by periods of drought. In this study, 115 potato genotypes were evaluated among 56 of the andigena group and 59 phureja to observe genetic variation in physiological traits that may be linked to drought tolerance. Eleven attributes were evaluated in genotypes tolerant and susceptible to drought stress. The genotypic variation of the materials was evaluated with a total of 968 SNP-type molecular markers, subjected to two soil moisture conditions. Association analysis was performed using the GWASpoly program to determine possible allelic interactions between genotypes with different ploidy levels. Analyses were corrected using population structure and parentage matrix as fixed cofactors. Significant SNPs were associated with phenotypic characteristics under contrasting water conditions for traits such as days to flowering, relative water content, tuber number and plant height. MYC-type transcription factors were associated with plant height, number of tubers per plant and plant water balance, demonstrating the multifunctionality of these regulatory proteins. While the HOS1 gene could be linked to the reduction of flowering time. These results will be the starting point for future studies for the validation of the markers, so that they can be used in potato drought stress breeding programs.