ESTIMATION OF GENETIC VARIABILITY IN DIFFERENT MORPHOLOGICAL AND BIOCHEMICAL TRAITS IN BANGLADESHI AMAN RICE GENOTYPES - Md Nayeem Sharker; Md Masud Rana; Tapon Kumar Roy; Mohammad Gulzarul Aziz; Ahmed Khairul Hasan (Journal of Animal and Plant Sciences, 2026)
This study comprehensively evaluates the morphological, biochemical, and grain quality of traditional aman rice landraces to understand their genetic variation and breeding potential. Twenty-four rice genotypes, including 23 landraces from different agro-ecological zones and one modern check (BRRI dhan87), were cultivated under randomized complete block design during the 2023 aman season at Bangladesh Agricultural University. Morphological traits such as plant height, tiller number, panicle length, grain weight, and yield components exhibited significant variations, with some landraces like Tulshimala and Bashful showing notably high performance. Biochemical analysis revealed considerable divergence in amylose and amylopectin contents, influencing grain texture and cooking quality; for instance, BRRI dhan87 had high amylose (24.09%) and low amylopectin, while landraces like Ashini and Binni showed opposite patterns, indicative of suitability for sticky rice. Grain color parameters assessed via CIE Lab colorimetry demonstrated wide variability, with light and dark grains distributed across genotypes, affecting consumer preferences and marketability. The evaluation of cooking and eating qualities, including elongation ratio, cooking time, water absorption, and alkali spreading value, highlighted diverse culinary attributes among landraces. Genetic analysis through variance components, heritability, and genetic advance indicated high heritability for key traits such as amylose content, sterile spikelets, and grain yield, suggesting their potential for improvement. Multivariate analyses, including PCA and cluster analysis, revealed large genetic diversity and grouped genotypes into five distinct clusters, with inter-cluster distances indicating significant genetic divergence. Clusters III and V, containing Kachamota, Isnishona, Binni, Moirul, and Sishumoti had the highest mean yield and quality attributes. Overall, the findings highlight the rich genetic reservoir of traditional rice landraces, emphasizing their value for breeding programs aimed to improve yield and grain quality.
Keywords: journal article; Rice germplasm; amylose; elongation ratio; heritability; genetic diversity; genetic coefficient of variation