Effects of Biological Nano-Selenium on Yield, Grain Quality, Aroma, and Selenium Content of Aromatic Rice

Selenium (Se) is one of the human essential elements and the input of Se for its biofortification is common in rice production to meet the demand for Se in the population. Biological nano-selenium (nano-Se) is a new type of nanoscale microbial synthetic material. However, the effects of biological nano-Se on aromatic rice performance metrics, such as yield formation, grain quality parameters, and the biosynthesis of 2-acetyl-1-pyrroline (2-AP, the key component of aromatic rice aroma), have rarely been reported. Therefore, this study conducted a field experiment with two cropping seasons and two aromatic rice genotypes to explore the effects of the foliar application of biological nano-Se on aromatic rice performance metrics. The results showed that the foliar application of biological nano-Se at 3–4 days before panicle differentiation or the heading stage increased the grain yield of aromatic rice. Dry matter accumulation and the leaf area index increased under Nano-Se application. Furthermore, the foliar application of Nano-Se at 3–4 days before panicle differentiation significantly enhanced the activity of peroxidase, superoxide dismutase, catalase and reduced malondialdehyde content. The foliar application of Nano-Se at the grain-filling stage also increased 2-AP content. In addition, nano-Se application substantially increased the grain Se content in aromatic rice.