Influence of Nitrogen Fertilization and Other Factors on Yield, Prussic Acid, Nitrate, and Total Nitrogen Concentrations of Sudangarss Cultivars1

Abstract

AbstractHerbage yields, total N, prussic acid, and nitrate‐N concentration of seven sudangrass [Sorghum sudanense (Piper) Stapf] forages treated with five levels of N (O, 22, 44, 88, and 176 kg/ha applied at seeding and after the first and the second clippings) were determined from a field experiment. The sudangrass cultivars represented included: sudangrass varieties (‘Piper’ and ‘Sweet’), sudangrass‐sudangrass hybrid (‘Trudan I’), forage sorghumsudangrass hybrids (‘Sweet Sioux’ and ‘Haygrazer’), and grain sorghum‐sudangrass hybrids (‘DeKalb SX‐11’ and ‘Horizon SP‐110’).Yield increases from N applications were nonsignificant for the first clipping but increased with increasing N increments through the 88 kg N/ha for'clippings 2 and 3. Nitrogen fertilization increased total N, prussic acid, and nitrate concentration at each clipping. The Sudangrass varieties (Sweet and Piper) and sudangrass hybrid (Trudan I) were the highest in total N percentage. Haygrazer and Horizon SP‐110 generally contained the lowest N percentage.