One hundred sixty-seven rice varieties representing 20 different rice growing countries were used to study the available varietal diversity pertaining to amylase content (AC) and paste viscosity parameters through cluster analysis. AC and paste viscosity parameters were measured using Auto Analyzer and Rapid Visco Analyzer (RVA-3D model) respectively. Based on the AC, the varieties were classified into waxy, low, intermediate, high amylose groups and each group included 21, 58, 64 and 24 varieties respectively. Cluster analysis based on paste viscosity profiles for low AC group (58) was grouped varieties class of 13, 21, 17, and 7. The intermediate AC group was further classified into three clusters each comprising 24, 16 and 24 varieties. Cluster 1 and 3 had mean intermediate paste viscosity (PV), low setback (SB) and high breakdown (BD) indicating good eating quality and are very soft on cooking. In this study the Japanese rice varieties showed good cooking quality, low AC, high PV and BD and low SB. In contrast, the Iranian cultivars such as Local Sadri showed good cooking quality, had intermediate levels of AC and SB and recorded high PV and BD. The enormous varietal diversity found within each group renders the breeder to make effective selections for quality according to consumer choice.
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