Author
SCHARF, P - UNIV OF MO | |
Kitchen, Newell | |
DAVIS, J - UNIV OF MO | |
Sudduth, Kenneth - Ken | |
LORY, J - UNIV OF MO |
Submitted to: Agronomy Abstracts
Publication Type: Abstract Only Publication Acceptance Date: 11/9/2000 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Previous research has shown that N fertilizer need for corn can vary widely, both between fields and within fields. However, producers almost always apply the same N fertilizer rate to whole fields, and vary N fertilizer rates minimally if at all over whole farms. Matching N fertilizer rates more closely to N needs could produce both economic and environmental benefits. Our objective is to test a range of innovative N management systems for their ability to match N rate recommendations to N needs at a field scale. We conducted experiments at 3 locations in 1999 and 3 locations in 2000. Systems evaluated include current Missouri recommendations, preplant and sidedress soil tests, variable yield goal based on soil electrical conductivity, and sidedress N rates based on corn color measured in either aerial photographs or with a ground-based spectral radiometer. Optimum N fertilizer rate varied widely in some fields (range > 100 kg N/ha) and much less in others. Systems will be evaluated based o both economic and environmental performance. |