SOIL 4213 BIOEN 4213 History of Using Indirect Measures for detecting Nutrient Status

1. SOIL 4213BIOEN 4213History of Using Indirect Measures for detecting Nutrient Status Oklahoma State University

2. Field Element Size • Area which provides the most precise measure of the available nutrient where the level of that nutrient changes with distance

3. FES should theoretically identify • 1. The smallest resolution where cause and effect relationships can be identified • 2. The precise resolution where variances between paired samples of the same size (area) become unrelated and where heterogeneity can be recognized • 3. The resolution where misapplication could pose a risk to the environment • 4. The treated resolution where net economic return is achieved. • 5. The resolution where differences in yield potential may exist

4. Review • Science: 283:310-316 • By 2020 global demand for rice, wheat, and maize will increase 40% • People have been predicting yield ceilings for millennia, and they’ve never been right “Matthew Reynolds” CIMMYT • Supercharging Photosynthesis: Reproduce the C4 cycle in rice • Role of Biotechnology in Precision Agriculture

5. Absorption of Visible Light by Photopigments SPAD 501, 502 (430, 750) Sunlight reaching earth Phycoerythrin Chlorophyll b Phycocyanin Absorption B-Carotene Chlorophyll a 300 400 500 600 700 800 Wavelength, nm Lehninger, Nelson and Cox

6. Short wavelength High frequency High energy Long wavelength Low frequency Low energy Yellow-green Yellow Violet Blue Green-blue Blue-green VISIBLE Color Transmitted Microwaves and short radio Violet Blue Green Yellow Orange Red Radio, FM, TV Gamma Rays Ultraviolet VISIBLE Color Absorbed Infrared X-Rays 0.01 10 380 450 495 570 590 620 750 1x106 1x1011 wavelength, nm Electronic Vibrational Rotational transitions transitions transitions

7. Short wavelength High energy Long wavelength Low energy Phycoerythrin Chlorophyll b Phycocyanin B-Carotene Chlorophyll a Ultraviolet Infrared X-Rays 0.01 10 380 450 495 570 590 620 750 wavelength, nm

8. CH3 CH3 CH3 CH3 CH3 CH3 RNH2 RNH2 RNH2 RNH2 | | | | | | | | | | | | | | | | 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 Wavelength, nm Near-Infrared AbsorptionMajor Amino and Methyl Analytical Bands and Peak Positions

9. Sensor Design Micro-Processor, A/D Conversion, and Signal Processing Photo-Detector Optical Filters Ultra-Sonic Collimation Sensor Plant and Soil target

10. History of Using Indirect Measures for Detecting Nutrient Status • NIRS analyzer which is connected to a computer focuses infrared rays on a prepared sample of dried pulverized plant material. The instrument measures protein, fiber and other plant components because each one reflects infrared rays differently. • Samples and standards (previously characterized) and then mathematically compared

11. History of Using Indirect Measures for Detecting Nutrient Status • NIRS (near infrared reflectance spectroscopy) • Measuring the vibrations caused by the stretching and bending of hydrogen bonds with carbon oxygen and nitrogen. • Each of the major organic components of a forage or other feed has light absorption characteristics. • These absorption characteristics cause the reflectance that enables us to identify plant composition

12. Chlorophyll Meters • Minolta: SPAD (soil plant analysis development unit ) 501 & 502 • www.specmeters.com/aneb.htm • http://agronomy.ucdavis.edu/uccerice/afs/agfs0394.htm • http://www.store.ripplecreek.com/category-greenformulas.html • light absorbance (light attenuation) at 430 (violet) and 750 nm (red/NIR transition) • no tissue collection • Leaf chlorophyll (SPAD) vs Leaf N concentration and NO3-N

13. Short wavelength High energy Long wavelength Low energy Phycoerythrin Chlorophyll b Phycocyanin B-Carotene Chlorophyll a Ultraviolet Infrared X-Rays 0.01 10 380 450 495 570 590 620 750 wavelength, nm

14. On-the-go-chemical-analyses • ‘SoilDoctor’ selective ion electrode mounted on the shank of an anhydrous ammonia applicator • Electromagnetic induction (EMI) • http://oldsci.eiu.edu/physics/DDavis/1160/Ch21Ind/Farady.html • VERIS • measurements (Missouri) • predicting grain yield • sand deposition • depth to clay pan

15. Use of EM as a data layer to better predict yield potential

17. On-the-go-chemical-analyses • On-the-go sensors for organic matter and ground slope (Yang, Shropshire, Peterson and Whitcraft) • Satellite images • Aerial images (NIR sensitive film)

18. Implications • Reports of improved correlation between indirect measures and yield (EMI) versus soil test parameters • Soil testing (process of elimination) • no single parameter is expected to be correlated with yield • K vs yield • P vs yield • N vs yield • pH vs yield

19. Spectral Radiance • Radiance: the rate of flow of light energy reflected from a surface • Measuring the radiance of light (at several wavelengths) that is reflected from the plant canopy • Photodiodes detect light intensity (or radiance) of certain wavelengths (interference filters, e.g., red, green, NIR) that are reflected from plants and soil.

20. White Light Interference Filter Photodiode Phycocyanin Chlorophyll b B-Carotene Phycoerythrin Chlorophyll a 380 450 495 570 590 620 750 wavelength, nm

21. Normalized Difference Vegetation Index(NDVI) = NIR ref – red ref / NIR ref + red ref (up – down) excellent predictor of plant N uptake Units: N uptake, kg ha-1