The Comparison of Red Greenseeker and Crop Circle

The Comparison of Red Greenseeker and Crop Circle in a Sugar Beet Canopy John A. Lamb University of Minnesota and Mark W. Bredehoeft Southern Minnesota Beet Sugar Cooperative NUE 2006

Sugar beet top yield 2004 Y = -11402 + 20665 X r = 0. 34* Y = -11157 + 18705 X r = 0. 62** Y = -13397 + 19142 X r = 0. 40** NUE 2006

TW Clara City 0 N NDVI = 0. 66 C. V. = 10% TW Clara City 130 N NDVI = 0. 84 C. V. = 2% NUE 2006 July 13, 2005

Objectives • Determine if sensors can predict sugar beet canopy near time of harvest. • Compare the red greenseeker and crop circle sensors for sugar beet canopy. NUE 2006

Methods NUE 2006

Methods • • 3 locations with small plots 3 varieties 5 to 6 N rates Harvest sugar beet tops and determine dry matter for each plot. NUE 2006

Correlations (r) DM DM G 7/13 G 7/28 G 8/9 G 9/15 G 9/27 C 9/15 NUE 2006 G 7/13 G 7/28 0. 45 G 8/9 G 9/15 G 9/27 C 9/15 C 9/27 0. 37 0. 64 0. 65 0. 64 0. 60 0. 51 0. 91 0. 56 0. 23 0. 10 0. 49 0. 08 0. 44 0. 19 -0. 03 0. 51 0. 01 0. 67 0. 65 0. 63 0. 92 0. 83 0. 88 0. 90 0. 71

Correlation between GS and CC r = 0. 82 NUE 2006

Top DM and NDVI (GS) r = 0. 63 NUE 2006

Top DM and NDVI (CC) r = 0. 60 NUE 2006

TW site 2005 Variety 1 2 3 DM (lb/A) NDVI (GS) NDVI (CC) 3767 0. 79 0. 68 3892 0. 80 0. 68 4047 0. 81 0. 69 N rate (lb/A) 0 90 110 130 150 NUE 2006 3340 3737 3836 4450 4147 0. 79 0. 80 0. 82 0. 80 0. 66 0. 68 0. 69 0. 70 0. 68

BL site 2005 Variety 1 2 3 DM (lb/A) 3711 3370 3779 NDVI (GS) NDVI (CC) 0. 81 0. 68 0. 79 0. 65 0. 83 0. 69 N rate (lb/A) 0 70 90 110 130 150 NUE 2006 3048 3127 3556 3921 3931 4095 0. 80 0. 81 0. 82 0. 67 0. 68 0. 69

Conclusions • There is a relationship between Top DM and NDVI as measured by sensors. • The sensors, while not producing the same NDVI numbers, work similarly in predicting Top DM. NUE 2006

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Questions? ? NUE 2006

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