1. Sensing Soybean Canopy Development Responses to and K Nutritional Stress

Normalized difference vegetative index (NDVI) has been correlated with physiological plant parameters and used to evaluate plant growt h. Recently, active canopy reflectance sensors have been used to determine N nutrition al needs of corn, wheat and forage grasses. There is little information about the use of this technique to detect soybean nutrient deficiencies. The objective of this work was to determine th e ability of the NDVI sensor to detect P and K deficiencies, and grain yield reduction,...