A Comprehensive Molecular, Biochemical, Histochemical, and Spectroscopic Characterization of Early and Medium Duration Rice Genotypes Investigating Dry Matter Accumulation Efficiencies.

ABSTRACT

Investigation on accumulation of cell wall components over critical growth stages will surely provide a new insight into dry matter accumulation studies in rice. An elevated biomass production provides an alternative strategy of yield improvement, which in turn maneuvers the species concerned as potential dual-purpose crop. On that note, present study was carried on 33 early and 39 medium duration rice genotypes. The average cellulose accumulation was 6.51% and 8.17% in early and medium duration genotypes, respectively, at flowering stage, which later on dipped to 1.43% and 3.46%, respectively, at physiological maturity. The gene specific marker MDgsp-5.a exhibited highest estimate of polymorphic information content (PIC), i.e., 0.685, closely followed by MDgsp-6.a with polymorphic information content (PIC) of 0.683. The control genotypes, i.e., Pratap and Mandakini, are grouped under the same cluster, i.e., Cluster-I.A, indicating their inherent genetic divergence from that of potential accumulators pertaining to cellulose accumulation. Pratap and Mandakini failed to produce peaks of conspicuous form at 3342 cm-1 and 1635 cm-1, bearing out by their low performance pertaining to cellulose and lignin accumulation at the later stages of development, respectively. From histochemistry studies, it was observed that the cell walls of sclerenchyma, peripheral vascular bundles, and parenchyma of the culm transections in control genotypes stained lightly than that of prolific accumulator cell walls, thus corroborating the findings of compositional analysis. The variation in cell wall thickening is primarily accounted due to altered carbohydrate accumulation across the growth stages as explored under scanning electron micrograph.