HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Hawkins, J. A. Articles by Lundvall, J. P. Search for Related Content PubMed Articles by Hawkins, J. A. Articles by Lundvall, J. P. Agricola Articles by Hawkins, J. A. Articles by Lundvall, J. P. Related Collections Nitrogen Nutrient Management Soil Fertility and Productivity

Using Relative Chlorophyll Meter Values to Determine Nitrogen Application Rates for Corn

^a Dep. of Agronomy, Iowa State Univ., Ames, IA 50011-1010
^b Farm Services Agency, Elkader, IA

View larger version (35K): [in this window] [in a new window]   Fig. 1. Chlorophyll meter (CM) readings at the R1 corn growth stage as related to the nitrogen rate difference (ND) from the economic optimum nitrogen rate (EONR) for corn following soybean (SC), 74 site-years in 1999–2005; and for continuous corn (CC), 28 site-years in 1999–2004. Regression curves were generated from regression models given in Table 1. The UCL and LCL represent the upper and lower confidence limits (95%), respectively, of the fitted regression model.

View larger version (31K): [in this window] [in a new window]   Fig. 2. Relative chlorophyll meter (RCM) values at the R1 corn growth stage as related to the nitrogen rate difference (ND) from the economic optimum nitrogen rate (EONR) for corn following soybean (SC), 74 site-years in 1999–2005; and continuous corn (CC), 28 site-years in 1999–2004. Regression curves were generated from regression models given in Table 1. The UCL and LCL represent the upper and lower confidence limits (95%), respectively, of the fitted regression curve model.

View larger version (18K): [in this window] [in a new window]   Fig. 3. Average chlorophyll meter (CM) readings at the V8, V15, R1, and R3 corn growth stages as related to the nitrogen rate difference (ND) from the economic optimum Nitrogen rate (EONR), corn following soybean (SC) and continuous corn (CC) from five sites in 2003. Response curves were generated from regression models given in Table 2.

View larger version (19K): [in this window] [in a new window]   Fig. 4. Average relative chlorophyll meter (RCM) values at the V8, V15, R1, and R3 corn growth stages as related to the nitrogen rate difference (ND) from the economic optimum nitrogen rate (EONR), corn following soybean (SC) and continuous corn (CC) from five sites in 2003. Response curves were generated from regression models given in Table 2.