A method for obtaining a plant, in particular a cultivated lettuce plant
(L. sativa), with a lasting resistance to a pathogen, in particular
Bremia lactucae, comprised of providing one or more specific DNA markers
linked to one or more resistance genes, determining the presence of one
or more resistance genes in a plant using these DNA markers, subsequently
crossing a first plant comprising one or more resistance genes with a
second plant comprising one or more resistance genes, and selecting from
the progeny a plant in which one or more resistance genes are present by
using the DNA markers. The invention further relates to the plants
obtained with this method, seeds and progeny of these plants, as well as
progeny thereof.