Submitted to: International Conference on Precision Agriculture Abstracts & Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: July 17, 2002
Publication Date: July 24, 2002
Citation: McMurtrey, J.E., Daughtry, C.S., Doraiswamy, P.C., Walthall, C.L., Hunt, E.R., Corp, L.A. 2002. Development of spectrally based canopy pigment index for nitrogen needs in corn crops. In: Proceedings of the International Conference on Precision Agriculture. 1(1):1601.
A spectrally based nitrogen need index for detecting changes in a field corn canopy's primary plant pigments chlorophyll a and b, total carotenoids, and other canopy attributes was tested over field sites. The initial testing was done in an irrigated corn production area with AVIRIS data in 1999 in Shelton, Nebraska. Further testing in 2001 was done in a rain-fed agriculture area in Beltsville, Maryland. Data from AISA and AVIRIS were used to test versions of spectral indexes based on the absorption in the red of total chlorophyll in the canopy, and the absorption of chlorophyll b plus the reflectance of the carotenoids and dead leaf spots and senescent leaves of the canopy which effect the yellow edge of the spectrum. The indexes were compared to NDVI and several other hyperspectral indices. A technique is proposed for further studies and suggestions are provided for methodology improving the recommendation of N rate in different site specific (pixel) areas of corn fields.