Variation in zinc (Zn) concentration in the grain of 50 local rice varieties from Southern Thailand was examined by diphenyl thiocarbazone (DTZ) staining (intense, medium, low, and nil) and chemical analysis. Intense staining was found in the aleurone layer of 94% of the varieties, in the embryo 56% of the varieties and endosperm 12% of the varieties. Variation was found in the DTZ staining intensity of the embryo and endosperm of individual grains, with Shannon-weaver diversity index (H) of the DTZ staining at 0.15-1.00 for the embryo and 0.00-1.00 for the endosperm. Chemical analysis found the Zn concentration in brown rice grain ranging between 18-34 mg Zn/kg, 7 varieties were considered high grain Zn (29-34 mg Zn/kg). The Zn concentration in the husk... |