Abstract:The paper reports a new finding that Fe++ with high concentrations (0.44-7.16mmol/L)is another effective stimulating factor other than the reported ones like CO2,ethylene,etc.Under submergence,4 out of 19 tested chemicals, at the same concentration of 1.79mmol/L,inhibited the seedling growth of rice, only FeSO4 significantly stimulated it, and the other ones had no effeCt. In aerobic condition,this stimulation still occur, but with a smaller extent. No obvious genotype difference was observed in the response to ferrous ion,which might imply that this stimulation behavior is one of the ways for rice to adapt flooded condition. High concentration of ethylene had a similar stimulative effect like Fe++ on the seedling growth of rice. This finding may probably help to improve the seedling establishment in the direct seeding, in which germinated seeds are sowed under flooded soil surface.