nitrogen, plant nutrition, fertilizer management, tillage, crop rotation, manure effects, soil quality, sustainability
Environmentally sound nitrogen (N) management is necessary to simultaneously achieve high crop yields and protect surface and groundwater quality. We evaluated a hand-held chlorophyll meter as a diagnostic tool for improving management for corn (Zea mays L.). Five N fertilizer rates (0, 67, 134, 201 and 280 kg N ha-1) were evaluated in one study, and in a second study, the meter was used to evaluate the N status of corn plants grown under varying tillage (chisel plow vs no-till), crop rotation (continuous corn vs corn-soybean [Glycine max (L.) Merr.]), and N management treatments. Meter readings were taken at several plant growth stages in both studies and correlated with plant N concentrations and grain yield. The chlorophyll meter readings detected differences in corn plants receiving low and high fertilizer N rates, as well as those grown with different tillage, N fertilizer management, and crop rotation practices. We recommend taking measurements between plant growth stages V9 and V12 and conclude that chlorophyll meters can be effective tools for improving N fertilizer management.
Journal of the Iowa Academy of Science
© Copyright 1999 by the Iowa Academy of Science, Inc.
Siambi, M. M.; Karlen, D. L.; and Shibles, R. M.
"Chlorophyll Meter Assessments of Corn Response to Nitrogen Management Practices,"
Journal of the Iowa Academy of Science: JIAS: Vol. 106:
, Article 5.
Available at: http://scholarworks.uni.edu/jias/vol106/iss2/5