Fazel-Najafabadi, M., Peng, J., Peairs, F.B., Šimková, H., Kilian, A., Lapitan, N.L.V.
EUPHYTICA
203:
607-614,
2015
Keywords:
RWA resistance, RWA biotype 2, Marker-assisted selection, Simple sequence repeat markers, Hordeum vulgare
Abstract:
The RWA, Diuraphis noxia (Kurdjumov),
is a devastating insect pest of wheat (Triticum
aestivum L.) and barley (Hordeum vulgare) in the
United States and in many parts of the world. The use
of D. noxia-resistant cultivars is an economically
useful approach for protecting cereals from this aphid.
However, there are few genes conferring resistance to
the most predominant US biotype (Biotype RWA2).
Wheat line CI2401, originating from Tajikistan, has
been identified to be resistant to RWA2. An F2-derived
F3 (F2:3) segregating population developed from a
cross between CI2401 and Glupro (a high quality
susceptible wheat cultivar) was used to genetically
map the resistance in CI2401. Seedlings from F2
individuals and F3 families were infested with RWA2
aphids. Seedling reactions were scored as resistant or
susceptible based on the degrees of leaf rolling and
chlorosis. The observed segregation ratios in the F2
and F3 generations indicate the presence of a major
dominant gene controlling resistance to RWA2. The
gene, named Dn2401, was genetically mapped to the
short arm of chromosome 7D. Xbarc214 mapped
1.1 cM and Xgwm473 mapped 1.8 cM distal and
proximal, respectively, to the gene. Association studies
using more than 12,000 SNPs and SilicoDArTs
confirmed the presence of a major signal associated
with resistance on chromosome 7DS. In addition, a
minor signal was detected in chromosome 1D. The
markers developed in this study will be useful for
marker-assisted-breeding for resistance to RWA2.
Fulltext: contact IEB authors
IEB authors: Hana Šimková
