2023/12/09 by Kerlan, Marie-Claire, Marhadour, Sylvie, Caromel, Bernard +4
#0 #Autotétraploïde #Glycoalcaloïdes #Hétérozygotie #Mildiou #Nématode #Pomme de terre #Résistance #Sélection assistée par marqueurs #Virus
paper · doi:10.17180/8a3r-m431
Marker-assisted selection (MAS) is only possible if molecular markers are easy to handle and informative. In potato, a tetraploid and highly heterozygous species, SAM is poorly developed. In our study we developed two approaches: 1) search for molecular markers linked to traits of interest in diploid segregating populations and test of their transferability at the tetraploid level and 2) test of molecular markers that have already been published in different tetraploid genetic backgrounds. The targeted traits were resistance to pathogens (late blight caused by Phytophthora infestans, cyst nematodes Globodera rostochiensis and G. pallida, virus Y) and glycoalkaloid content in tubers. In the case of a monogenic control (like resistance to late blight conferred by the R1 gene originating from Solanum demissum or the resistance to the Y virus conferred by the Ry gene originating from S. stoloniferum), the published markers have been validated in different genetic backgrounds. For the H1 gene conferring resistance to G. rostochiensis, markers available at the time of the project were not found to be associated with resistance in our material but other markers have since been validated. In the case of oligogenic resistance, illustrated by the resistance to G. pallida, which is controlled by two QTL, markers flanking the large effect QTL GpaVspl were tested successfully in different diploid and tetraploid backgrounds. Two markers linked to the low effect QTL GpaXIspl were also validated. These markers were transferred to the French breeders who are now using them in their breeding programs. For polygenic quantitative traits (partial resistance to late blight and glycoalkaloid content), it seems not realistic to consider SAM for the moment.