Aroma and Agro-morphological Diversity in Traditional Rice (Oryza sativa) Germplasm from Eastern India

Aromatic and Morphological Variation in Eastern Indian Rice

Abstract

Traditional aromatic and quality rice (Oryza sativa L.)landraces from eastern India harbour valuable grain quality traits, yet their agromorphological diversity and fragrance genetics remain insufficiently characterized. This study evaluated 183 accessions from the
Indian National GeneBank to characterize phenotypic variation and assess allelic diversity at the BADH2 fragrance locus. Twenty-two
agro-morphological traits were recorded, aroma was assessed using the KOH test, and allele-specific PCR was employed to detect the
8-bp functional deletion in exon 7 of BADH2. The accessions exhibited wide phenotypic variation, particularly in grain length, grain
width, kernel shape, and pigmentation traits. Aroma profiling classified 42% of accessions as strongly aromatic and 36% as
moderately aromatic. Multiple-factor analysis and clustering showed weak state-wise structuring, indicating considerable overlap
among accessions, likely reflecting historical seed exchange. Genotyping showed that 31% of accessions carried the homozygous
aromatic allele; however, a substantial proportion of aromatic accessions lacked the deletion, suggesting that additional genetic
factors may contribute to fragrance in this germplasm. These findings highlight the diversity of agro-morphological and aroma-related traits in eastern Indian rice and provide a useful baseline for future genetic studies and quality-oriented breeding
programmes, as well as for the conservation and utilization of the aromatic landraces.