Abstract:
Destruction of crops due to submergence is a growing concern
in flood-prone environments. This has led urgent need for the
incorporation of the Swub-I locus for submergence tolerance in
chromosome 9 of popular rice varieties. Swarna, a popular rice variety in
South Asia was crossed and backcrossed to IR49830, a Sub-I donor using
Marker Assisted Backcrossing (MAB). In this descriptive study, plants in
the third filial generation of the second backcross (BC,F3) stage were
screened for submergence-tolerance. DNA was extracted from leaf
samples collected from each plant then genotyped for inheritance at
specific loci of interest thru Marker Assisted Selection (MAS) using
molecular markers (SSR markers) in the Sub-/ locus (RM316, SSC3,
SSRI, RM464, RM464A), as well as molecular markers for other regions
(RM8S5, RM119, RM163, RM246, RM428). Certain plants that contained
IR49830 (donor parent) genotype in the Sub-1 locus and Swarna (recurrent
parent) genotype in all of the other loci are of particular interest.
Candidate plants were seeded and subjected to submergence check.
Results indicated that certain rice lines contained Swarna genotypes in all
but the Sub-I locus, thus, identifying submergence-tolerant rice lines for
Swarna.
