Mapping of QTLs involved in nematode resistance, tuber yield and root development in Solanum sp.

Abstract

A backcross population, derived from the cross (S. tuberosumxS. spegazzinii)xS. tuberosum was used to map QTLs involved in nematode resistance, tuber yield and root development. Complete linkage maps were available for the interspecific hybrid parent as well as the S. tuberosum parent, and interval mapping for all traits was performed for both. Additionally, the intra- and inter-locus interactions of the QTLs were examined. The Gro1.2 locus, involved in resistance to G. rostochiensis pathotype Ro1, that was previously mapped in the S. tuberosumxS. spegazzinii F1 population, was located more precisely on chromosome 10. A new resistance locus, Gro1.4, also conferring resistance to G. rostochiensis pathotype Ro1, was found on chromosome 3. Different alleles of this locus originating from both parents contributed to the resistant phenotype, indicating multiallelism at this locus. No interlocus interactions were observed between these two resistance loci. For resistance to G. pallida no QTLs were detected. One minor QTL involved in tuber yield was located on chromosome 4. Two QTLs involved in root development and having large effects were mapped on chromosomes 2 and 6 and an epistatic interaction was found between these two loci.

Plant Molecular Biology — A Laboratory Manual

“…Here, there is a large difference in average dormancy between genotype classes A-and aa for marker MI only if marker M3 has genotype bb. Kreike et al (1996) have also reported evidence of epistasis between QTLs in potato. For example, to achieve long dormancy, favourable alleles at both MI and M3 should be present (row 1, Table 7.3).…”

Potato resistance to quarantine diseases

“…Феномен HR описывается как инкапсуляция питательной клетки растения, в которую внедрилась личинка нематоды, слоем некротических клеток с последующей дегенерацией питающего синтиция в течение недели (Rice et al, 1985). Большинство известных QTL локусов устойчивости к цистообразующим нематодам детерминируют частичную устойчивость к одному или более патотипам (Kreike et al, 1993(Kreike et al, , 1996Caromel et al, 2005).…”

Chromosome regions between centromeres and proximal crossovers are the physical sites of major effect loci for yield in potato: Genetic analysis employing meiotic mutants

“…Molecular support for major effect TTY loci between centromeres and first-crossover sites remains to be obtained. Extensive QTL mapping of TTY genes is still incipient in potatoes (36)(37)(38). The unique behavior of FDR gametes can be also useful in this regard because it provides a tool to generate informative segregating populations and for subsequent placement of QTL in linkage maps (9).…”