Aromatic rice (
Oryza sativa L. subsp.
japonica
Kato) is globally popular due to its pleasant aroma and enchanting
flavor. 2-Acetyl-1-pyrroline (2-AP) is recognized as the only major flavoring compound in aromatic rice. Plant nutrition
affects the production and accumulation of 2-AP in rice, but the effect of time-specific nutrient application during the
developmental phases of rice on 2-AP has not yet been reported. Three N levels (N0: 0 kg ha
-1, N1: 30 kg ha
-1, and N2: 60
kg ha
-1) at the booting stage were applied to a popular aromatic rice cv. Yungengyou 14, to assess the accumulation pattern
of 2-AP, proline, and N as well as relationships among the investigated indices regarding 2-AP accumulation. Among
all other plant parts, the highest 2AP contents were found in ear axes and flag leaves, i.e. 17.04%-18.26% and 14.37%-15.05% at 17 as well as 18.41%-22.74% and 14.38%-15.75% at 30 DAF under all N-levels. Interestingly, N application at
the booting stage also maintained higher proline and 2-AP contents in different plant tissues during the early grain filling
stage. Hence additional N dose at booting stage could improve the grain aroma contents of aroma rice while considering
the amount of N fertilizer added.
