Foliar application of selenium (Se) at heading stage induces regulation of photosynthesis, yield formation, and quality characteristics in fragrant rice

In order to study the effect of foliar application of sodium selenate on fragrant rice performance at the heading stage, the present study was conducted with two fragrant rice cultivars, 'Meixiangzhan-2' and 'Xiangyaxiangzhan'. At the heading stage, six concentrations of sodium selenate solution (0, 10, 20, 30, 40, and 50 mu mol L-1) were sprinkled to plants. Our results showed that foliar application of sodium selenate increased chlorophyll contents in rice leaves and upregulated net photosynthetic rate at the grain-filling stage. The enhancement was observed in grain yield, seed-setting rate, and in 1,000-grain mass. The highest yield and net photosynthetic rate were both recorded at 40 mu mol L-1 treatment for both cultivars. Furthermore, foliar application of sodium selenate also improved some grain quality attributes, such as head rice rate and crude protein content. The Se concentration in fragrant rice grain also increased due to sodium selenate application. In conclusion, sodium selenate has potential to be the exogenous plant growth regulator in fragrant rice production to increase yield and quality.