Effects of irrigation and fertilization on yield and potassium content of corn and on available potassium contents of a Davidson soil

Abstract

Abstract A field experiment was conducted to determine the effects of fertilization and irrigation on the yield and chemical composition of corn (Zea mays L.) and on the available soil K. The soil type was Davidson clay loam. Five rates of N, P, and K were applied annually. All plant residue was removed from the plots each year when the corn was harvested. Available K in the 0‐to 15‐cm soil depth decreased rapidly the first three years. The rate of decrease in available soil K decreased during the last three years. The rate of decrease was slightly greater on irrigated than on non‐irrigated plots. Amounts of available K in the 0‐to 180‐cm depth in 1972, increased with increased rate of applied K. Non‐irrigated plots contained 83% as much available K as similarly K fertilized irrigated plots. The K concentration of leaves was increased with K fertilization in 1968 and with irrigation each year. The K concentration of silage was increased with K fertilization on irrigated and non‐irrigated plots and by irri...