QTL Analysis of New Sources of Resistance to Erwinia carotovora ssp. atroseptica in Potato Done by AFLP, RFLP, and Resistance‐Gene‐Like Markers

Abstract

The two most important bacterial diseases of cultivated potato, blackleg of stems and tuber soft rot, are caused by Erwinia species. Genetic resistance currently present in cultivars is insufficient to protect the crop. New sources of polygenic resistance to Erwinia carotovora ssp. atroseptica (van Hall) Dye (Eca) have been selected in diploid hybrids originating from intercrossing Solanum tuberosum L with the wild species S. chacoense Bitter and S. yungasense Hawk. One F1 hybrid population derived from these materials was used to locate, on the molecular map of potato, quantitative trait loci (QTL) for resistance of tubers and leaves to Eca. A linkage map was constructed based on AFLP and RFLP markers including three resistance‐gene‐like (RGL) markers. Clustering of AFLP markers in putative centromeric regions was observed. QTL analysis revealed complex inheritance of resistance to Eca. Genetic factors affecting resistance to Eca were located on all 12 potato chromosomes. Putative QTL for tuber resistance were identified on 10 chromosomes. The QTL with the largest and most reproducible effect on tuber resistance mapped to chromosome I. Effects on leaf resistance were less reproducible than effects on tuber resistance. Putative QTL for leaf resistance were identified on 10 chromosomes. Inheritance of tuber and leaf resistance to Eca was largely independent. Several QTL for resistance to Eca were linked to RGL loci. Four of those QTL mapped to genomic segments that have been shown to contain factors for qualitative and quantitative resistance to different pathogens in potato, tomato (Lycopersicon esculentum Mill.), or tobacco (Nicotiana tabacum L.).

The novel, major locus Rpi-phu1 for late blight resistance maps to potato chromosome IX and is not correlated with long vegetation period

“…The gene Gm conferring resistance to Potato virus M has been recently identiWed in a similar region on potato chromosome IX (Marczewski et al 2006), as well as a QTL for resistance to Erwinia carotovora ssp. atroseptica (Zimnoch-Guzowska et al 2000).…”

Single Nucleotide Polymorphisms in the Allene Oxide Synthase 2 Gene Are Associated With Field Resistance to Late Blight in Populations of Tetraploid Potato Cultivars

“…Some SNP positions and alleles differed, however, between the five fully sequence-characterized StAOS2 alleles and the 14 StAOS2 SNPs scored in the tetraploid breeding populations of this study. This indicated that the StAOS2 alleles present in the tetraploid germplasm were not all the same as the StAOS2 alleles described in Pajerowska-Mukhtar et al (2008), which originated from diploid, more exotic germplasm generated in prebreeding programs (Oberhagemann et al 1999;Zimnoch-Guzowska et al 2000). In fact, the variation of resistance explained by StAOS2 alleles in the experimental, diploid QTL mapping populations was with 10-14% (Pajerowska-Mukhtar et al 2008), much smaller than the variance explained in the association experiment reported here (39-43% for rAUDPC; 31-36% for MCR).…”

Comparison of RAPD, RFLP, AFLP and SSR markers for diversity studies in tropical maize inbred lines

“…It is also known that the AFLP technique has lower initial costs and is more transferable across species than SSR methods. Techniques based on AFLPs have been applied to genome mapping (Zimnoch-Guzowska et al, 2000), DNA fingerprinting (Powell et al, 1996), genetic diversity studies (Russell et al, 1997) and parentage analysis (Gerber et al, 2000;Lima et al, 2001).…”