Assessment of genetic variability and principal component analysis (PCA) for rice starch viscosity traits

Rice quality evaluation has a significant impact in deciding consumer acceptability and its suitability for various end-user applications. In the current investigation, we have evaluated a set of 54 genotypes, including landraces, popular varieties and basmati accessions for amylose content and viscosity profile to study the significant componential traits that contribute to rice quality through PCA. These cultivars were also categorized based on stability ratio, a valuable attribute that signifies rice's stability and cooking quality. Significant variation was found between the cultivars for all traits evaluated in the study. PCA was employed in the study to investigate the relationship between viscosity profile parameters and AAC and their contribution to phenotypic variability among these accessions. PCAanalysis revealed the maximum contribution of the first two PCs (76.41 %) to the total variability. Further, based on their stability ratio, the accessions were categorized into three stability groups: 12 cultivars in the high, 39 in the medium and 3 in the low stability ratio category. The study led to the identification of traits that contributed the maximum to the observed variation and these findings can be efficiently utilized in determining the rice quality and the end-use application of rice starch. The findings of this study can be directly applied in breeding programs to improve consumer-preferred rice varieties by selecting high-quality parental lines and targeted genetic improvement and in food processing industries by tailoring rice for specific end-use applications and optimizing processing conditions based on viscosity parameters.