Molecular characterization of aromatic Oryza sativa L. cultivars from West Bengal, India

The present study reports analysis of 50 rice cultivars from West Bengal for aromatic grains. Cytological analysis revealed the presence of stable mitotic chromosome number (2n = 24) among donor and descendants of each rice variety. The odour test after alkaline treatment of grains revealed 14 cultivars viz. the Tulaipanji, Gobinda bhog, Tulshi bhog, Bhog dhan, Khas dhan, Chini atap, Kalojire, Phulpakri, Kalanunia, Prasad bhog, Kalojoha, Katari bhog, Badsha bhog and Danaguri varieties were aromatic. Partial genomic sequencing of the betaine aldehyde dehydrogenase-2 gene, which is implicated in the aroma trait, confirms the presence of an 8 bp (5′-GATTATGG-3′) deletion mutation and 3 SNPs (A6246T, A6248T, C6258T) in exon-7 of the Tulaipanji, Gobinda bhog, Tulshi bhog, Bhog dhan, Khas dhan, Chini atap and Kalojire aromatic varieties but not in Nayanmuni and Roygorh non-aromatic varieties of rice. Interestingly, the Tulaipanji, Prasad bhog, Kalojire, Bhog dhan, Tulshi bhog and Kalanunia aromatic landraces also possess awns and may have been domesticated very recently.