Influence of sodium hypochlorite on seed germination and early seedling growth of rice (Oryza sativa L.) variety Tarum

Sodium hypochlorite (NaOCl) solution has been commonly used for the sterilization of seeds, and it has been reported to have stimulatory effect on seed germination, breaking seed dormancy, seedling growth, alleviation of salinity, in vitro seedling growth and shoot regeneration, and control in seed-borne pathogens in many species. The aim of this study was to determine the effect of concentration of sodium hypochlorite solutions (0, 1, 2, 4, 6, 8 and 10%) for 24 h on seed germination percentage (GP), germination rate (GR), mean germination time (MGT) and seedling growth of rice. The results showed that the highest seed germination percentage equal to 97.5% was obtained from 2% NaOCl treatment and lowest equal to 89% from 10% treatment after 14 days. Increase in concentration of NaOCl to 10% decreased GP and MGT. Therefore, 4% sodium hypochlorite could increase root length, shoot length and root dry weight by 7, 11.7 and 11% as compared to control, respectively. The best results were obtained from 2 to 4% NaOCl concentration. However, a considerable decrease in many parameters was observed at 10% level. The sodium hypochlorite treatment was more compatible than soaks with commercial seed strilizants, inexpensive, easily available, simple procedure and had less potential for injury to seed.