1989. Combining conventional plant breeding procedures with molecular based approaches. Genome, 31: 1014 -1026.This presentation covers the professional experience of the authors in the plant breeding research section of the MaxPlanck-Institut f i r Ziichtungforschung, Koln. Results available from current projects are discussed in the framework of breeding strategies aimed at the improvement of plant traits based on few or many genes. The following aspects are considered: use of genes for virus, insect, and herbicide resistance; tolerance to abiotic stresses (resistance to desiccation is studied in several model tissues and plants); identification and isolation of genes governing seed quality in cereals; possibility of tagging relevant genes in potato by the use of the exogenous transposon Ac; use of anther culture in potato breeding by changing the ploidy level from tetraploidy to diploidy and the reverse; marker-assisted selection in potato (a restriction fragment length polymorphism is under development and already molecular probes can be used to identify diploid and tetraploid potato strains).