Methods and compositions for identifying downy mildew resistant cucumber plants

摘要

The present invention relates to methods for identifying cucumber lines having increased resistance to Downy Mildew, and identification of genetic markers linked to gene(s) conditioning such increased disease resistance. The present invention also relates to methods of breeding cucumber plants from lines having increased Downy Mildew resistance by marker-assisted selection, compositions including nucleic acid probes or primers which are useful for such marker assisted selection, and plants and plant parts produced by such methods.

主权项

1. A method of obtaining cucumber germplasm comprising the steps of:
a) assaying cucumber plants for the presence of at least a first genetic marker genetically linked to a QTL that confers resistance to Downy Mildew; and b) selecting at least a first cucumber plant comprising the genetic marker and the QTL that confers resistance to Downy Mildew; wherein the QTL maps to a position between the sequence represented by SNP marker NN0228457 and SNP marker NN0228148, which map to approximately 25.2 cM and 82.7 cM on the genetic map of the linkage group termed cucumber chromosome 5, respectively; wherein the QTL maps to a position between the sequence represented by SNP marker NN0225012 and SNP marker NN0227587 which map to approximately 20.6 cM and 87.4 cM on the genetic map of the linkage group termed cucumber chromosome 4, respectively; or wherein the QTL maps to a position between the sequence represented by SNP marker NN0223782 and SNP marker NN0226638 which map to approximately 22.5 cM and 88.4 cM on the genetic map of the linkage group termed cucumber chromosome 2, respectively.