Coastal Bermudagrass Forage Production and Chemical Composition as Influenced by Potassium Source, Rate, and Frequency of Application1

Autor: Adams, William E., White, A. W., McCreery, R. A., Dawson, R. N.
Zdroj: Agronomy Journal; May 1967, Vol. 59 Issue: 3 p247-250, 4p
Abstrakt: The influence of K source, rate, and frequency of application was studied on intensively managed ‘Coastal’ bermudagrass grown on Cecil sandy loam soil. The N, P, and K contents of the forage and the forage production were not influenced by the chloride or sulfate source of K. The 185 kg/ha K rate applied as KCl in 4 equal splits—at the initiation of spring growth and after each of the first 3 harvests—produced about 15,700 kg/ha of forage and the most efficient K utilization. Efficiency was reflected by (i) more uniform seasonal forage distribution and (ii) a more uniform K content (average 1.5%) throughout the growing season as contrasted with applying all the K in the spring. This management practice of splitting the K application increased the kilograms of forage produced per centimeter of rainfall by 14% and the efficiency of applied K by 14%. The K‐Ca‐pyrophosphate source produced significantly more forage with a significantly lower K content than either the sulfate or chloride sources of K. One hundred eighty‐five kg/ha of K applied in four equal splits, rather than at one time, doubled the exchangeable K in the surface 15 cm of soil, produced earlier spring growth of the Coastal bermudagrass, and a higher forage yield in the first harvest.
Databáze: Supplemental Index