Abstract: Exogenous selenium was sprayed at different growth stages of the foxtail millet to study the change rule of quality and grain selenium content, to determine the optimum spraying selenium period for foxtail millet, so as to provide a theoretical basis for production of selenium-rich foxtail. The varieties Changnong 35, Jigu 20 and Jingu 50 were used as test materials. The field experiment was designed by random block group, setting spray water for control (CK), foliar spraying Na₂SeO₃ 67.84 g/ha at seedling stage, heading stage and filling stage to study on influence of quality, grain selenium content, accumulation and translocation of selenium in foxtail millet. The result showed that different growth period of spraying selenium treatment all could improve quality of foxtail millet, foxtail millet in filling stage spraying selenium on millet quality traits to improve was the best. The lysine content of Jingu 50, Jigu 20 and Changnong 35 increased by 0.03,0.05,0.02 percentage points respectively, folic acid content was 2.4%, 7.5%, 5.5% higher than that of control, respectively.The content of crude protein and crude fat in selenium spraying treatment reached extremely significant level with the control during grain filling stage(P<0.01).Spraying time impact on grain selenium content in filling stage > heading stage > seedling stage, foxtail millet grain selenium content was increased by average of 8.0-9.9 times compared to the CK within the scope of the safety of the intake of selenium. Filling stage was to improve the millet organic selenium conversion rate and the utilization ratio of the grain selenium crucial period.The organic selenium conversion rates of Jingu 50, Jigu 20 and Changnong 35 treated by spraying selenium at grain filling stage were 13, 13 and 10 percentage points higher than those of the control, respectively, and there was a significant difference between them (P<0.05), compared with the control, the selenium harvest index increased by 5.32, 5.82 and 2.70 percentage points after selenium treatment in the filling stage. The application of selenium in filling period could improve the quality of grain, increase the grain selenium content, the conversion of organic selenium and the utilization of selenium. Filling stage was an optimal period of foxtail millet foliar spraying exogenous selenium.

Key words: Foxtail millet, Quality, Selenium content, Conversion rate of organic selenium, Selenium harvest index

CLC Number: 

• S515

• S143.7