Two additive QTLs conferring broad-spectrum resistance in potato to Globodera pallida are localized on resistance gene clusters

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

“…The resistance gene cluster 'to the South' contains the late blight resistance gene Rpi-moc1of S. mochiquense (Smilde et al 2005), Ph-3, a major QRL for late blight resistance in tomato (Chungwongse et al 2002), Sw-5, a tomato gene for tospoviruses resistance (Brommonschenkel and Tanksley 1997), Nx encoding hypersensitive resistance to Potato virus X of S. phureja (Tommiska et al 1998) and Gpa6, a QTL for potato resistance to Globodera pallida (Rouppe van der Voort et al 2000). Resistance loci 'to the North' of Rpi-phu1 are Tm-2a from Solanum peruvianum conferring resistance to Tomato mosaic virus (Tanksley et al 1992), Fr1 for tomato resistance to Fusarium oxysporum f. sp.…”

Development and application of a 20K SNP array in potato

“…This paper explores the ability to apply graphical genotyping on unrelated tetraploid varieties as a tool for identification of haplotypes and a tool for mapping PVY resistance. Furthermore we show that this method also enables the identification of introgression segments of the Gpa5 locus (Rouppe van der Voort et al 2000) and the Ry-f sto locus (Song et al 2005;Flis et al 2005). However, we also show that other traits without a clear most recent common ancestor (MRCA) are beyond the potential of this method, because identity-by-descent (IBD) is a crucial requirement of this method.…”

“…These monogenic traits are easy to phenotype and therefore were very suitable for the primary mapping studies as a proof of concept, however these are typical traits for which MAS is not needed. Mapping studies in the same period in the early nineties resulted in the identification of dominantly inherited resistance genes such as R1 and R3 against Phytophthora infestans (El-Kharbotly et al 1994), H1 against Globodera rostochiensis (Gebhardt et al 1993), followed by the QTLs Gpa5 and Gpa6 conferring resistance to Globodera pallida (Rouppe van der Voort et al 2000). These four resistance genes are widely present in the contemporary potato varieties.…”

“…Diploid mapping populations were either generated from diploid parents, which by prickle pollination and parthenogenetic development of the unfertilized eggs were extracted as primary dihaploids from tetraploid potato varieties (El-Kharbotly et al 1994;Rouppe van der Voort et al 2000;Song et al 2005) or from crosses with diploid parents from the diploid gene pool comprising both cultivated land races and wild species for example in Yencho et al (1998). QTL mapping in diploid bi-parental population potato was further extended to quantitatively inherited traits such as glycoalkaloid content (Yencho et al 1998), yield and starch yield (Schäfer-Pregl et al 1998), cold induced sweetening (Menéndez et al 2002) and enzymatic discolouration (Werij et al 2007).…”

“…Another example of the application of graphical genotyping relates to the Gpa5 vrn locus on chromosome 5 conferring Globodera pallida nematode resistance, initially described using the diploid clone 3704-76 (Rouppe van der Voort et al 2000). The resistant parental clones 3778-16 and 3704-76 are dihaploids extracted from the tetraploid progenitor clones AM 78-3778 and AM 78-3704, respectively.…”