Abstract: To better serve the optimization of selenium fertilizer formulation and spraying system, we should clarify the redistribution of selenium applied on leaves after entering into crops and screen out the appropriate selenium form for foliar spraying. We examined the effects of foliar spraying of four forms of selenium on selenium absorption and accumulation in different leaves, stems and roots of rice “Daohuaxiang 2” by hydroponic method at seedling stage. The results showed that the distribution of exogenous selenium in leaves was related with different positions. The selenium concentration in the sprayed leaves (the 4th leaf) was the highest, and decreased gradually along the upper and lower leaves. The organic selenium tended to be transported to young leaves. Foliar spraying of sodium selenite significantly increased selenium accumulation in rice seedlings compared with sodium selenate, zinc selenite and selenomethionine treatments. Selenium concentration in leaves under the treatment of spraying sodium selenite increased by 131.4 times, up to 129.21 mg·kg^-1, and that in the stems and roots was 18.6 times and 2.2 times higher than that in the control, respectively. Therefore, selenium in sprayed leaves at the seedling stage could be transported to upper and lower leaves. A large amount of selenium was accumulated in the lower first leaves of selenium-sprayed leaves. Sodium selenite had the best effect on selenium accumulation in rice.

Key words: foliar spraying of selenium, leaf position, sodium selenite, selenium form, translocation factor.