Foliar application of selenium to field corn
Cary, E.E.; Rutzke, M.
Agronomy Journal 73(6): 1083-1085
Much of the northeastern quarter of the USA produces feed corn (Zea mays L.) that contains too little selenium (Se) to meet animal nutritional requirements. This experiment was conducted to determine if Se concentration in corn ('Cornell 281') could be increased by foliar application of Se. Selenium was applied by hand sprayer to corn growing on Mardin silt loam (Typic Fragiochrept) in a field when the 4th to 6th leaves were the last fully expanded or when tassels were just emerging. Treatments were 0, 7.5, and 15 g Se/ha added as Na2Se0, in 359 liter/ha of water containing 48 ml of surfactant. Selenium rate, stage of growth, and Se × stage of growth were highly significant (P<1%). At maturity, the concentration of Se in the whole plant minus the ear vs. grain and ear leaf blade vs. grain was linearly correlated, with r=0.99** and r=0.88*, respectively. The concentration of Se in grain with no added Se was 0.01 ppm Se. Doubling the Se concentration sprayed on the corn increased the Se concentration from 0.05 to 0.12 ppm Se in grain for the early treatment and from 0.14 to 0.24 ppm Se in grain from the late treatment. The increase in Se concentration in plants sprayed at early tassel stage over those sprayed at a younger age apparently was associated with the total amount of Se intercepted by the plant. Foliar application may be an efficient and safe way to increase Se in feeds and forages.