Abstract:
This study evaluated phenotypic variability among 14 selected rice (Oryza sativa L.) varieties using 16 quantitative
morphological and physiological traits. Analysis of Variance (ANOVA) revealed significant differences (p < 0.05)
across all traits, with coefficients of variation ranging from moderate to high, indicating substantial diversity.
Physiological parameters measured at the reproductive stage, including photosynthetic and gas exchange traits,
exhibited significant genotypic effects, while morphological descriptors reflected clear varietal differentiation despite
potential environmental influences. Correlation analysis identified key trait associations relevant for yield
improvement, highlighting their utility in breeding selection. Principal Component Analysis (PCA) revealed that the
first five components (eigenvalues greater than 1) accounted for 81.8% of the total variance, with significant
contributions from yield and phenological traits. Cluster analysis based on standardized data grouped the varieties into
two major clusters, separating highly similar subgroups and identifying the most divergent pair—Basmati 2000 and
Kisan Basmati. These findings demonstrate substantial phenotypic and genotypic divergence within the germplasm,
providing valuable parental combinations for breeding programs that target yield potential and environmental
adaptation.
