Relative Efficiency of Broadcast Versus Banded Phosphorus for Corn1

Abstract

AbstractExperiments were conducted on Zanesville, Elliott, and Muscatine soils to determine the relative efficiency, with respect to corn yields, of broadcast P as compared to banded P. The 16 fertilizer treatments consisted of 4 rates of banded P and 4 rates of broadcast P in factorial combinations.Yields from each of the 3 soils were used to calculate a multiple regression equation for each soil. The equation is of a quadratic form, and it expresses the relation between yield and rates of banded and broadcast P. The regression equations account for 77 to 88% of the variation in yield.The largest yield increases from added P were 1287, 1474, and 873 pounds of corn per acre for the Zanesville, Elliott, and Muscatine soils, respectively. With all the P either banded or broadcast, the relative efficiency of broadcast P ranged from 0.49 to 1.23 for the 3 soils For a given soil, the relative efficiency of broadcast P varied with rate. At 35.2 pounds of P added per acre, higher yields were obtained on Zanesville and Elliott soils if a combination of banded and broadcast application were used than if all the P was added either banded or broadcast. Banding all the P gave higher yields than the other application methods if 17.6 and 8.8 pounds of P per acre were added. Yields from the Muscatine soil were not dependent on whether all the P was drilled, broadcast, or applied by a combination of both methods.