Investigation of differential 2-acetyl-1-pyrroline concentration in inferior and superior spikelets of fragrant rice

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Zhaowen Mo
Haowen Luo
Wu Li
Yuzhan Li
Hua Tian
Shenggang Pan
Haidong Liu
Meiyang Duan
Xiangru Tang


2-acetyl-1-pyrroline, aromatic rice, grain position, nitrogen


Fragrant rice is popular globally due to its desirable grain quality and strong fragrance. 2-Acetyl-1-pyrroline (2AP) is believed to be one of the key aromatic compounds found in fragrant rice. The present study investigated the differential 2AP concentration in inferior and superior spikelets of fragrant rice. Results showed that inferior spikelets produced higher aroma than superior spikelets, but opposite trend was observed in grain yield. A significant positive correlation was observed between grain yield and contribution ratio to yield, number of grains/m2, filled number of grains/m2, percentage of filled grains, and total nitrogen content in grains. Besides, 2AP content at different panicle positions showed a significant negative relationship with contribution ratio to yield but a significant positive correlation with moisture content. The findings demonstrated that it was feasible to improve fragrance and maintain grain yield by reducing the difference between superior and inferior spikelets during grain filling period. The results of the study revealed fragrance in grains in relation to superior and inferior spikelets in fragrant rice panicles.

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