Short-term water deficit stress induces anthocyanin accumulation and changes in grain yield and yield components in colored rice grain

Abstract

The effect of short-term water deficit stress was studied, on anthocyanin content and yield components in rice using a comparative study of three different water management regimes, continuous flooding (CF), safe-alternate wetting and drying irrigation (AWD) and critical-AWD, with the aim of gaining better understanding of the effectiveness of modified AWD treatments to increase the anthocyanin content in the Riceberry variety. The results showed that both the critical-AWD and safe-AWD conditions promoted a longer period to flowering than the CF condition by 7 d and 4 d, respectively, while plant growth slowed. The average grain yield per pot and the harvest index decreased significantly by decreasing the soil moisture content. The safe-AWD treatment had the highest water use efficiency (0.66 g/m³) which was not significantly difference to critical-AWD. The total anthocyanin content (TAC) in unpolished colored rice grain progressively increased in response to decreasing water supply. The TAC of safe-AWD and critical-AWD plants was 2-fold and 4-fold, respectively, higher compared to well-watered plants.