The amplified fragment length polymorphism (AFLP) assay is an efficient method for the identification of molecular
markers, useful in the improvement of numerous crop species. Bulked Segregant Analysis (BSA) was used to
identify AFLP markers associated with water-stress tolerance in barley, as this would permit rapid selection of
water-stress tolerant genotypes in breeding programs. AFLP markers linked to water-stress tolerance was identified
in two DNA pools (tolerant and sensitive), which were established using selected F2 individuals resulting from a cross
between water-stress-tolerant and sensitive barley parental genotypes, based on their paraquat (PQ) tolerance, leaf
size, and relative water content (RWC). All these three traits were previously shown to be associated with
water-stress tolerance in segregating F2 progeny of the barley cross used in a previous study. AFLP analysis was
then performed on these DNA pools, using 40 primer pairs to detect AFLP fragments that are present/absent,
respectively, in the two pools and their parental lines. One separate AFLP fragment, which was present in the
tolerant parent and in the tolerant bulk, but absent in the sensitive parent and in the sensitive bulk, was identified.
Polymorphism of the AFLP marker was tested among tolerant and sensitive F2 individuals. The presence of this
marker that is associated with water-stress tolerance will greatly enhance selection for paraquat and water-stress
tolerant genotypes in future breeding programs.