Identification of putative candidate gene markers for grain zinc content using recombinant inbred lines (RIL) population of IRRI38 X Jeerigesanna

Abstract

Nutrients in food crops can be enriched by adopting biofortification. Identifying the target quantitative trait loci (QTL) genes will help achieve biofortification with greater precision and accuracy. The objective of this experiment is to estimate grain zinc content, evaluation of candidate gene markers in recombinant inbred lines (RIL) derived from IRRI38 X Jeerigesanna and validation of putative candidate gene markers with rice accessions. Grain zinc content ranged from 16.1 to 35.5 ppm with an average of 23.7 ppm. Among twenty four candidate gene markers, eight showed polymorphism and out of three simple sequence repeats (SSR) markers, three showed polymorphism. Single marker analysis revealed that four (OsNAC, OsZIP8a, OsZIP8c and OsZIP4b) candidate gene markers showed significant variation among RIL population with a phenotypic variation of 4.5, 19.0, 5.1 and 10.2% respectively. Validation with 96 rice genotypes showed three markers (OsZIP8a, OsNAC and OsZIP4b) with phenotypic variation of 11.0, 5.8 and 4.8%, respectively.

Keywords: Zinc, biofortification, single-marker analysis (SMS) and marker assisted selection (MAS)

African Journal of Biotechnology, Vol. 13(5), pp. 657-663, 29 January, 2014