SCAR markers of the R-genes and germplasm of wild Solanum species for breeding late blight-resistant potato cultivars

Abstract

New races of Phytophthora infestans rapidly defeat potato late blight (LB) resistance based on Solanum demissum germplasm, and breeders search for new sources of durable LB resistance. We developed and verified six sequence characterized amplified region markers recognizing the race-specific genes R1 and R3 of S. demissum and the broad-spectrum resistance gene RB of S. bulbocastanum and the germplasms of these species and used them to screen 209 accessions of 21 wild Solanum species. In addition to S. demissum, homologues of R1 and R3 were found in several species of series Demissa,Longipedicellata and diploid Tuberosa; R3 homologues were also detected in S. bulbocastanum,S. cardiophyllum and S. ehrenbergii. The RB homologues were found in a wider range of Solanum species. The markers of R1 and R3 genes reliably discerned between germplasms of S. tuberosum ssp. tuberosum and wild sources of LB resistance. Following introgression, the species-specific markers of demissum and bulbocastanum germplasm were rapidly lost, whereas the markers of R1 and R3 genes lasted through several meiotic generations and were maintained at high frequencies in modern potato cultivars. The presence of these markers in demissoid potato cultivars was significantly associated with LB resistance, presuming that both genes contribute to overall defence response.

ANTICIPATORY BREEDING: MOLECULAR MARKERS AS A TOOL IN DEVELOPING DONORS OF POTATO (Solanum tuberosum L.) LATE BLIGHT RESISTANCE FROM COMPLEX INTERSPECIFIC HYBRIDS

“…more common than it was suggested earlier. The same was confirmed by the results of Solanum wild species screening performed by us earlier [17,24,26,33]. Similar results were obtained by H. Rietman using effectoromics method [32].…”

“…The markers used by us have been developed for late blight resistance R genes initially characterized in four Solanum species, S. bulbocastanum, S. demissum, S. stoloniferum and S. venturii. Comparison of interspecies potato hybrid clones and wild Solanum species used during development of these hybrids [24,26] has confirmed that the composition of R genes in hybrids mostly corresponded to their parentages. R1, R2, R3a and R3b gene markers were most probably transferred from S. demissum, however, according to screening of the large collection of wild Petota section species [24], they could originate from other wild species indicated in parentages.…”

“…Comparison of interspecies potato hybrid clones and wild Solanum species used during development of these hybrids [24,26] has confirmed that the composition of R genes in hybrids mostly corresponded to their parentages. R1, R2, R3a and R3b gene markers were most probably transferred from S. demissum, however, according to screening of the large collection of wild Petota section species [24], they could originate from other wild species indicated in parentages. Genetic material of S. bulbocastanum was nor used for development of the studied hybrids, and in cases where we identify Rpi-blb1 gene marker, it was transferred from S. stoloniferum, a tetraploid species; presumably, one of its genomes originates from S. bulbocastanum [27].…”

“…DNA concentration was measured at  = 260 nm using UV/Vis NanoPhotometer P300 nanophotometer (IMPLEN, Germany). Genomic DNA amplification, cloning and amplicon sequencing methods have been described by us earlier [24]. PCR was performed in a DNA amplifier DNA Engine PTC-200 (Bio-Rad, USA) with 1.0 unit of Taq DNA polymerase (Fermentas, USA), and for R2-2500 marker with…”

Molecular markers for late blight resistance breeding of potato: an update

“…Sokolova et al. () developed three SCAR markers namely R1 ‐1205, R3 ‐1380 and Sdms‐523 recognizing the race‐specific genes R1 and R3 . These markers were validated in screening 209 accessions of 21 wild Solanum species for MAS application.…”