Development of STS and CAPS Markers Specific to Genomes in the Tribe Triticeae

Wild Triticeae grasses serve as important gene pools for forages and cereal crops. Knowledge on their ge-
nome compositions is pivotal for efficient utilization of this vast gene pool in germplasm enhancement pro
grams. Using DNA sequences of genome-specific RAPD markers, seleeted primers have been designed to
develop sequence tagged site (STS) markers. Genome specificity was lost for a majority of RAPD-to-STS
conversions due to the inward extension of primer sequences. However, successful eonversion has been
achieved for genomes E', E, St, H, Ns, W, V and Y (an unknown genome in many polyploid Elymus spe-
cies). Several cleaved amplified polymorphic sequence (CAPS) markers were also developed to distinguish
the E', E and R genomes. The identified STS and CAPS markers are useful in suggesting the presence of
certain genome(s) in Triticeae species and in identifying the alien chromosome or chromosomal segment in
wheat addition, substitution, or translocation lines. Use of STS markers has helped to identify wheat add-
tion lines with W- and Y-genome chromosomes derived from hybrids of hexaploid wheat Triicum aestivumn
(AABBDD) and hexaploid Elymus rectisetus (StStWWYY). Seven disomie wheat addition lines having dif
ferent Egenome chromosomes are eonfirmed by the CAPS markers for this genome. This study also pro-
vides evidence that barley yellow dwarf virus (BYDV) resistant germplasm lines from Purdue and China
are different those developed in Australia.