Nanosilica synthesis from rice husk and application for soaking seeds

Abstract

Nanosilica was synthesized from rice husk. At first, the rice husk ash was obtained by annealing at temperatures 700°C for 6 hours, then nanosilica particles were extracted by using 0.5N NaOH solution followed by forming gel with HCl acid solution. The structural features of the products were characterized by techniques including Energy dispersive X-ray, Field Emission Scanning Electron Microscopes, Fourrier Transformation Infrared, Fourrier Transformation Infrared. The results showed that the SiO₂ nanoparicles have average size about 30-100 nm and >98 % purity. The present experiment was conducted to test the beneficial effects of nanosilicon on the seed germination. Seeds (BC rice, Bacthom rice and bean) were analyzed with regard to germination percentage (GP), mean germination time, seed germination index, seed vigour index to investigate the efficiency of nanosilica. Among the treatments, the addition of 40 mg/L nanosilica for BC rice seed, 60 mg/L for Bacthom rice seed showed the most promising results that yielded significant differences from the control in terms. Compare to GP of BC and Bacthom sample after treatment (100%), GP of sample with no-nanosilica are 93.33% and 53.33%, respectively. Besides, the samples which added nanosilica have higher average length of shoot and root than blank sample.