Greenseeker in Sugar beet

John A. Lamb

University of Minnesota

Sugar beet studies

• Objective: Determine if disease resistant varieties differ in response to N.

• Treatments:– Three varieties – susceptible, mod, resistant– Five N rates – 70, 90, 110, 130, 150 soil nitrate-N (0-4

ft.) plus fertilizer.– Three locations– Small plots and field strips– Harvested tops, determined top yield, N conc, and N

uptake.

Sugar beet top results 2004(small plots)

0

50

100

150

200

0.6 0.7 0.8 0.9

NDVI 9/16/04 (Harvest)T

op

N u

pta

ke (

lb/a

cre)

0

2000

4000

6000

8000

10000

0.6 0.7 0.8 0.9

NDVI 9/16/04 (Harvest)

To

p y

ield

(lb

/acr

e)

All locations, varieties, and N rates

0

2000

4000

6000

8000

10000

0.7 0.75 0.8 0.85 0.9

NVDI 9/16/04

To

p y

ield

(lb

/A)

Sugar beet top yield 2004

Y = -13397 + 19142 X r = 0.40**

Y = -11157 + 18705 X r = 0.62**

Y = -11402 + 20665 X r = 0.34*

Does Red Greenseeker work with sugar beet?

NDVI = 0.32 C.V. = 40% NDVI = 0.39 C.V. = 44% NDVI = 0.43 C.V. = 40%

July 13, 2005

Buffalo Lake, MN

2005 measurements

NDVI = 0.64 C.V. = 22% NDVI = 0.76 C.V. = 12%

July 13, 2005

Buffalo Lake, MN

TW Clara City 0 NNDVI = 0.66 C.V. = 10%

TW Clara City 130 NNDVI = 0.84 C.V. = 2%

July 13, 2005

Fall 2005 plans

1.Repeat 2004 sampling.2.Measure spatial differences.

Sugar beet summary

• On an individualized site, there is a linear relationship between NDVI and sugar beet top amount.

• Data needs to be tortured more.

• During early season the Greenseeker does measure biomass of tops

• As NDVI increases, CVs decrease.

Corn information

• Before we did corn work, some modifications to the Greenseeker had to be made.– Hard on back so incorporated a backpack to

carry battery.– Needed better way to get the height in “man”

corn. Used flag pole holder with limited success.

– Tried some bike designs

Backpack and flag pole holder designs.

Bike designs

Corn measurements in 2005

• Corn fertilized in Corn-Sugar beet rotation.

• Treatments – 0, 120, and 200 pounds N/A.

NDVI (2005)

Nrate

lb/A

V6

6/23

V9

6/30

V11

7/6

V14

7/14

0 0.713 0.835 0.835 0.820

120 0.760 0.853 0.853 0.823

200 0.754 0.856 0.855 0.824

Stat ** ** ** NS

Questions?