Journal article
Estimating the nitrogen status of crops using a digital camera
Y Li, D Chen, CN Walker, JF Angus
Field Crops Research | ELSEVIER SCIENCE BV | Published : 2010
Abstract
Spectral reflectance of cereal canopies measured with a digital camera correlated closely with N status during the vegetative and early stem elongation phases. Photos of the crops taken at a height of about 1m were processed to indicate the canopy cover (CC) on a 0-1 scale representing the proportion of pixels that met a criterion of greenness, (1+L)Green-RedGreen+Red+L>0, where Green and Red are reflectance values of the green and red bands of the camera's colour detector and L is a soil base line. The values of CC measured at one site were closely correlated with values of leaf area index (LAI), above-ground biomass and N content for two wheat cultivars with different growth habits. The fu..
View full abstractGrants
Awarded by Australian Centre for International Agricultural Research
Funding Acknowledgements
We are grateful to Mark Branson, Mick Faulkner, Peter Hooper and Alan Mayfield for access to crops and loan of equipment and to Alexander Suladze for assistance with programming and Davide Cammarano for measuring the reflectance spectra in Fig. 1. The research was supported by a University of Melbourne early career research grant, a University of Melbourne-CSIRO collaborative grant and the Australian Centre for International Agricultural Research (project LWR/2003/039).