Adoption of direct-seeded rice (DSR) cultivation requires
sustainable weed management strategies for making it
viable. The development of herbicide-tolerant (HT) rice
varieties will help address this gap. Robin, an EMS induced
mutant of Nagina 22 (N22), tolerates the application of
imazethapyr, a broad-spectrum herbicide of the
imidazolinone group. A mutation in the OsAHAS
(acetohydroxyacid synthase) gene offers HT in Robin. The
mutant allele is named AHASrb. In the present study, we
developed a derived cleaved amplified polymorphic
sequences (dCAPS) marker, AKS-dAHAS, based on the
single nucleotide polymorphism (SNP) in AHASrb, which
had a G to A mutation at the 1880th position. This mutation
causes an amino acid substitution at 627th serine residue
to asparagine (S627N) in the AHAS enzyme. We have
demonstrated that AKS-dAHAS perfectly distinguishes the
wild type allele of Nagina 22 (AHAS) from the mutant allele,
AHASrb. AKS-dAHAS showed perfect co-segregation with
HT trait in two independent F2 populations. Unlike the linked
marker, RM6844, the AKS-dAHAS showed no recombinants
with the HT trait, ensuring utmost precision in selection for
imazethapyr tolerance. This marker enables precise transfer
of AHASrb into elite rice varieties through marker-assisted
breeding, thereby imparting imazethapyr tolerance making
them suitable for DSR cultivation.
Keywords: dCAPS, OsAHAS, herbicide tolerance, imazethapyr, direct-seeded rice
Year: 2021
Volume: 81
Issue: 3
Article DOI: 10.31742/IJGPB.81.3.2
Print ISSN: 0019-5200
Online ISSN: 0975-6906
Nitasha Grover, Aruna Kumar, Ranjith K. Ellur, Ashutosh K. Yadav, S. Gopala Krishnan, K. K. Vinod, Rakesh K. Verma, Viswanathan Chinnusamy, Prolay K. Bhowmick, Haritha Bollinedi, M. Nagarajan, M. Raveendran, Amitha Mithra V. Sevanthi, Nagendra K. Singh, Sheshshayee M. Sreeman, Trilochan Mohapatra and Ashok K. Singh info_circle