EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 1 Evaluation of Green Seeker for Nitrogen Fertilization in Cotton – Preliminary results in Alabama Shannon Norwood, Amy Winstead, Charles Burmester, Paul Mask, Dale Monks, John Fulton, Joey Shaw, Brenda Ortiz

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 2 Cotton Experimental Design    North Alabama (Heavy soils)  4 Treatments TTs Pre-plantSidedress N (lbs/ac) N Rich1500 No sidedress500 Standard7050 High sidedress50100

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 3 Experimental Design  Field strips  Field strips (8 rows x length of the field) N Rich – Rep 1 plot  Ramped calibration strip in the N Rich – Rep 1 plot Data Collection   GS data – 4 times during the growing season At sidedress (June 25 – 2008, 32 DAP) GS/ 2 weeks after sidedress (2008- Jul. 9 & 26, Aug. 6)  From three locations within each plot, samples for : Plant tissue for N analysis Plant Height SPAD 502 Meter readings (10 plants at each location)

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 4 Data Collection   Harvest Two middle rows Yield monitor Subsample for lint turnout

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 5  NDVI increase through time  increase in the cotton biomass. Results TTs Pre- plant Sidedress N (lbs/ac) N Rich 1500 No sidedress 500 Standard 7050 High sidedress Jun09-Jul25-Jul06-Aug

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 6 SPAD N Rich No Sidedress Standard High Sidedress 25-Jun09-Jul25-Jul06-Aug TTs Pre- plant Sidedress N (lbs/ac) N Rich 1500 No sidedress 500 Standard7050 High sidedress Results At sidedress At sidedress: No NDVI differences No NDVI differences btwn N Rich (150 lb N at planting) & No sidedress (50 lb N at planting) Standard TT (70 lb N ) had < NDVI than No sidedress (50 lb N) NDVI trend ~ SPAD trend but different NDVI No sidedress and High sidedress TTs – Same N rate at planting, but different NDVI maybe Plant height…biomass Later in the season, no much SPAD & NDVI relation….maybe Plant height…biomass? At sidedress

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 7 TTs Pre- plant Sidedress N (lbs/ac) N Rich 1500 No sidedress 500 Standard7050 High sidedress Jun09-Jul25-Jul06-Aug Results At sidedress NDVI and Petiole nitrate (ppm) At sidedress: At sidedress: Low petiole Nitrate  low NDVI (High siddress TT) sidedress, no much relation btwn NDVI and petiole Nitrate After sidedress, no much relation btwn NDVI and petiole Nitrate

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 8 Results NDVI vs. Lint Yield Differences in yield respect to N rate and time  Split application best ! N at planting: both rates  same NDVI Split application, slightly higher NDVI-6wks T1 T2 T3 T4

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 9 Results NDVI vs. Lint Yield 130 lb/ac yield difference btw T1 & T3  Same NDVI 2wks after sidedress T2 - Lowest yield  Highest NDVI at 2wks from sidedress, but lowest NDVI 6 wks from sidedress T3 – Highest yield  Similar NDVI than T1 throughout the season T1 T2 T3 T4

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 10 Results  NDVI increase through time  increase in the cotton biomass.  No much NDVI differences beyond 2wks after sidedress

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 11 SPAD readings Petiole nitrate (ppm) Results There were no significant differences between the treatments for petiole nitrate or chlorophyll readings

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 12 NDVI at sidedress vs. Lint Yield Results A difference of 47 lb/ac btwn T1 and T2, however equal NDVI at sidedress T1 T2 T3 T4

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 13 Conclusions  Yield responses to nitrogen application, especially split application of N  NDVI increase up to 2 wks (sidedress), later no differences.  At sidedress  no NDVI differences btwn treatments.  SPAD increases with split N application but no differences in NDVI

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 14 Development of a Cotton Fertilizer Prescription for Variable Rate Application in the Coastal Plain. Kip Balkcom Research Agronomist USDA-ARS Joey Shaw Soil Scientist Agronomy and Soils John Fulton Agricultural Engineer Biosystems Engineering

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 15 Development of a Cotton Fertilizer Prescription for Variable Rate Application in the Coastal Plain. Quantify cotton response to different N rates across management zones for site-specific agriculture applications. Relate N status of cotton to sensor based readings across the landscape to identify a relationship for variable N rate application. Identify cotton quality parameters across the landscape and relate to management systems.

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 16 Remote Sensing of Cotton in AL Location: E.V. Smith Research Center, Alabama, USA. * Soils : Sandy Loam ( Aquic and Typic Paleudults ). Size: 22 acres

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 17 Soil Survey Terrain Attributes Electrical Conductivity Soil surface Texture/SOC 20 x 9-m Characterization of Soils/Landscapes

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 18 Experimental Design  6 Replications  8 Transects or strips/rep crossing landscape  Transects divided on Grids of 60 ft. x 24 ft.  Tillage split into 4 N rates. 0, 40, 80, 120 lb ac. Wheat/Soybean Cotton Cluster 1 Cluster 2 Cluster 3 Cluster 4 Cluster 5

EVALUATION OF GREENSEEKER FOR NITROGEN FETILIZATION IN COTTON ALABAMA REPORT 19 Data Collection GreenSeeker data : 1 st sampling – Early squaring1 st sampling – Early squaring 2 nd sampling – Mid-bloom 2 nd sampling – Mid-bloom Collected plant measurements from “smart” cells. 25 uppermost mature leaves – N content + SPAD readings. Plant heights – 10 random plants. 1-m of row for whole plant biomass + N content. Calculate the seed cotton yields for each cell. Hand harvest - 50 bolls from each “smart” cell for seed N content.