In the present study, a set of 63 accessions of Aegilops
tauschii, the D-genome donor of bread wheat, was
evaluated for marker-trait association using SSR markers
and biotic and abiotic stress tolerance. Five accessions
of Ae. tauschii (TA1644, TA1642, TA1695, TA2452 and
TA2473) were resistant to Hessian fly whereas seven
(TA1649, TA2460, TA2450, TA2541, TA2470, TA2397 and
TA749) were resistant to leaf rust pathogen. However one
accession TA1695 was also resistant to pest green bug.
Significant associations across D-genome revealed that
chromosome 2D is associated with resistance to several
stress factors. Two alleles at Xgwm296 locus were
associated with resistance to leaf rust, Septoria leaf blotch,
green bug, and salt tolerance. Another locus Xgwm261
detected association for resistance to leaf rust, Septoria
leaf blotch and Hessian fly. The existence of a QTL for
tolerance to high salt concentration was also detected
through association with marker Xcfd11, located on this
chromosome. Furthermore association analysis also
detected two SSR markers, Xgwm261 and Xgdm35, each
with a fragment amplified in the leaf rust resistant
accessions while lacking in the susceptible accessions.
This study reveals the potential of association analysis in
identifying the genomic regions having strong influence
on useful traits. Through association mapping the
germplasm collections can be initially screened and
characterized to identify candidate genetic stocks and
genomic regions. Subsequently, bi-parental crosses can
be initiated for fine genetic mapping of genes or QTLs
through linkage analysis.
Keywords: Marker-trait association, SSR markers, biotic and abiotic stresses
Year: 2012
Volume: 72
Issue: 3
Article DOI: N/A
Print ISSN: 0019-5200
Online ISSN: 0975-6906
Sukhwinder-Singh info_circle
G. S. Chahal info_circle
P. K. Singh info_circle
B. S. Gill info_circle