Underpinning the soft nature of soak-n-eat rice - A physicochemical and molecular approach

Abstract

Soak-n-eat rice, a natural treasure of Eastern India, is popular rice based ethnic food item of the tribal peoples of Assam. In the present study, 22 low amylose containing glutinous Bora rice lines were explored for their unique ‘ready-to-eat’ properties, where physicochemical and molecular approach was used to investigate the science behind softness and finally the establishment of trait linked marker associated with this unique soft trait. Very low amylose content, pinholes in kernel, low final viscosity and detection of unique functional groups, made physicochemical properties of soft rice very distinct from normal rice. Polymorphic trait linked markers; a good number of SNPs in trait linked loci and down regulation of those loci during grain filling revealed the unique molecular basis of softness. RM190 is associated with amylose content and softness, confirmed as a trait linked marker by showing heterozygous band in hybrid lines with desired trait. This study may be the first holistic approach on soft rice for its unique soak-n-eat properties and developed hybrid lines may be the source of future environment friendly food.