Year of Publication
Master of Science (MS)
Plant and Soil Science
Dr. John H. Grove
The normalized difference vegetative index (NDVI) has been correlated with physiological plant parameters and used to evaluate plant growth. There is little information about the use of this technique to detect soybean nutrient deficiencies. The objective of this work was to determine the ability of the NDVI sensor to detect P and K deficiencies, and grain yield reduction, in soybean. During 2010 and 2011, NDVI measurements were made on a soybean field trial site known to exhibit yield responses to both P and K nutrition. Four replicates of 8 levels each of P and K nutrition were evaluated. The NDVI measurements were made with an active proximal sensor held parallel to the soil surface every seven days after V2, and until R2. At each measurement a mean NDVI value was found for each plot. Phosphorus deficiency was detected with the first NDVI measurement. Potassium deficiency was first detected just after V4. Differences in NDVI values due to P or K nutrition increased with continued crop development. There were significant R1 leaf composition and grain yield responses to improved P or K nutrition. The active proximal sensor was able to detect soybean growth differences due to P or K deficiencies in soybean.
Navarro, Martin M., "SENSING DEVELOPMENT OF A SOYBEAN CANOPY UNDER P OR K NUTRITIONAL STRESS" (2012). Theses and Dissertations--Plant and Soil Sciences. 12.