Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: September 1, 2006
Publication Date: November 13, 2006
Citation: Varvel, G.E., Wilhelm, W.W., Shanahan, J.F., Schepers, J.S. 2006. Nitrogen Fertilizer Applications for Corn Based on Sufficiency Index Calculations. In Annual meeting abstract [CD-ROM]. ASA, CSSA, SSSA, Madison WI. Technical Abstract: Corn was grown in both continuous corn and corn/soybean cropping systems under irrigation in the Platte Valley of Nebraska. The objective of the study was to determine whether in-season N stress measured by using chlorophyll meters could be used to determine N fertilizer applications. Four corn hybrids differing in yield potential, maturity, and stay green characteristics were tested in both the monoculture and rotation systems in combination with five N fertilizer rates. Normalized chlorophyll meter readings, denoted as a sufficiency index, at various growth stages appeared to be indicative of various levels of N stress for the various preseason N fertilizer applications.