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Bacterial blight (BB) of rice caused by the pathogen
Xanthomonas oryzae
pv.
oryzae
and the insect gall midge (GM) (
Orseolia oryzae
) are two major constraints of rice production. The present study was carried out to improve RPHR-1005, a stable restorer line of the fine-grain-type rice hybrid DRRH-3, for BB and GM resistance through marker-assisted backcross breeding (MABB). Two major GM resistance genes,
Gm4
and
Gm8
, and a major BB resistance gene,
Xa21
, were selected as target genes for transfer to RPHR-1005. Two sets of backcrosses were carried out to combine either
Xa21
+
Gm4
or
Xa21
+
Gm8
into RPHR-1005 using breeding lines in the genetic background of ISM possessing either
Gm4
or
Gm8
along with
Xa21
. Foreground selection was performed for
Xa21
,
Gm4
,
Gm8
, and the major fertility restorer genes
Rf3
and
Rf4
using gene-specific markers, while 61 polymorphic simple sequence repeat (SSR) markers were used for background selection and marker-assisted backcrossing was continued until BC
2
generation. A promising homozygous backcross-derived plant at the BC
2
F
2
generation possessing
Xa21
+
Gm4
, and another possessing
Xa21
+
Gm8
, were intercrossed to stack the target resistance genes. At ICF
4
(inter-crossed F
4
) , three promising lines possessing the three target resistance genes in a homozygous condition along with fine-grain type, complete fertility restoration, and better panicle exsertion than RPHR-1005 have been identified. Among these, a single line, # RPIC-16-65-125, showed better yield, was highly resistant to BB and GM, was of medium–slender grain type, and had complete fertility restoration along with better panicle exsertion and taller plant type than RPHR-1005. This is the first report of combining resistance against BB and GM in the genetic background of a hybrid rice parental line.