2. Materials and methods
2.1. Plant material
To generate grape genotypes that combine the Ren1 and Run1
genes, a cross was made between Kishmish vatkana and VRH 3082-
1-42, where the former was the male parent and the latter the
female parent. VRH 3082-1-42 is a progeny plant from the fourth
recurrent pseudo-backcross (BC4) of M. rotundifolia to V. vinifera
(Bouquet, 1986). Thus, the progeny resulting from the VRH 3082-
1-42×Kishmish vatkana cross is considered a M. rotundifolia–V.
vinifera BC5 hybrid family. Seeds resulting from this cross were
planted in Jiffy peat pots in the spring. Members of this progeny
are identified as Pecs-06-1/1-899, where the word Pecs-06-1 represents
the progeny and the numbers 1-899 represent the plant ID
within the population. Seedlings at the one-leaf-stage were then
transplanted into larger pots and grown in the greenhouse under a
canopy of mature PM-infected V. vinifera plants. The phenotype of
the seedlings was determined as resistant or susceptible at the end
of the growing season.