Canopy-scale wavelength and vegetative index sensitivities to cotton growth parameters and nitrogen status

• DOI: 10.1007/s11119-014-9383-4
• Publication Date: 2014-10-10T03:16:24Z
• Authors: T. B. Raper; J. J. Varco
• Keywords: Red edge; Lint

Temporal and spatial variability of plant available N in the humid southeastern region United States often results within-field over- under- application this nutrient to cotton. Although ground-based canopy reflectance has potential quantify crop status real-time drive variable rate fertilizer applications, currently utilized vegetation indices fail correlate strongly with status. Therefore, objective study was examine relationships between across wavelengths calculated ratios prior at flowering biomass, leaf tissue concentration, aboveground total content lint yield. Data collected during third week flower bud formation first 2008–2010 growing seasons Mississippi State, MS, USA. Analysis wavelength sensitivities indicated near 670 nm most highly correlated height, but relatively poorly yield, concentration. The strongest correlations yield were noted 700 nm. Subsequent analysis utilizing red edge more when compared relying on green or regions. Comparisons simple complex calculations inflection point suggested a simplified version Canopy Chlorophyll Content Index calculation may provide reasonable reliability for detection cotton