The Source of Silicon for Thai Riceberry Germinated on Top of an Aqueous Solution

Rice plants accumulate silicon (Si) in various parts of the body as a form of body protection as well as for fighting against stresses. In this study, we used Thai Riceberry grown on top of a Si-free water as a model to study Si accumulation. Scanning Electron Microscope and Energy Dispersive X-ray Spectrometer (SEM-EDX) together with Inductively Couple Plasma-Optical Emission Spectrometer (ICP-OES) were used. It was found that rice husks contained a large amount of Si in the form of silicon dioxide at an average level of 23,104.28 ± 2021.27 μg Si/g husk. Rice could grow well and accumulated Si in whole body tissues from 170.00 ± 126.48 μg Si/g tissue at the start of germination to 1,380.00 ± 667.16 μg Si/g tissue when the rice grew to 10 cm long. SEM-EDX analysis revealed that Si was accumulated the most in leaves and crystalized to form dumbbell shape-like bodies. Husks would therefore most likely be the source of Si during early germination and growth of the rice plant seedlings.