Km. Haymes et al., IDENTIFICATION OF RAPD MARKERS LINKED TO A PHYTOPHTHORA-FRAGARIAE RESISTANCE GENE (RPF1) IN THE CULTIVATED STRAWBERRY, Theoretical and Applied Genetics, 94(8), 1997, pp. 1097-1101
Bulked segregant analysis (BSA) was used to identify seven random ampl
ified polymorphic DNA (RAPD) markers linked to the Rpf1 gene. Rpf1 con
fers resistance to Phytophthora fragariae var. fragariae, the causal a
gent of red stele root rot in Fragaria spp. The bulked DNAs represente
d subsets of a F-1 population obtained from the cross Md683 x Senga Se
ngana which consisted of 60 plants and segregated in a 1:1 ratio for r
esistance or susceptibility to race 2.3.4 isolate NS2 of P. fragariae.
Seven markers were shown to be linked to Rpf1 and were generated from
four primers; five of these markers were in coupling phase and two in
repulsion phase with respect to the gene. A linkage map of this resis
tance gene region was generated using JoinMap 2.0(TM). Th, manner in w
hich Rpf1 and the linked markers co-segregated indicated that they are
inherited in a disomic fashion. These markers could enable gene pyram
iding and marker-assisted selection of resistance genes in strawberry
breeding programmes.