Effect of Foliar Application of Selenium Fertilizer on Yield, Selenium Content and Heavy Metal Contents of Waxy Maize

[Objectives] This study aimed to explore the effect of different concentrations of selenium fertilizer on the yield, selenium content and heavy metal contents of waxy maize, thereby providing reference for the scientific application of selenium fertilizer on waxy maize. [Methods] Different varieties of waxy maize (Guitiannuo 611, Guinuo 615 and Guiheinuo 609) were used as test materials. They were sprayed with different concentrations (0, 0.5, 1.0, 1.5 and 2.0 g/L) of water-soluble selenium fertilizer (Xinxibao) at the big flare stage, and the effect on the yield, selenium content and heavy metal contents of the waxy maize was analyzed. [Results] Foliar application of different concentrations of selenium fertilizer showed no significant effect on the yield and yield components of waxy maize. As the concentration of selenium fertilizer increased, the grain selenium content of different varieties of waxy maize increased. Among them, the increase of Guinuo 615 was the largest, of which the selenium content reached 0.265 mg/kg, 2.82 times that of the control (water). The cadmium and arsenic contents of different varieties of waxy maize decreased with the increase of the concentration of selenium fertilizer sprayed. Among the waxy maize varieties, the cadmium and arsenic contents of Guitiannuo 611 dropped the most significantly, up to 52.94% and 77.78%. In waxy maize, the correlation coefficients between selenium content and cadmium, arsenic contents were -0.550 9 (P<0.05) and -0.853 0 (P<0.01), respectively. [Conclusions] Spraying exogenous selenium fertilizer had no obvious effect on the yield of waxy maize. However, the increase of the concentration of exogenous selenium fertilizer could significantly increase the selenium content and reduce the cadmium and arsenic contents in grains of different varieties of waxy maize.