New Zealand Plant Protection 64 (2011): 287
Crop sensing technology is a new tool being rapidly adopted by farmers as a key component of precision agriculture. This technology uses sensors to calculate normalized difference vegetative index (NDVI) by emitting red and near infrared light towards the crop and measuring the crop's reflectance. NDVI is used to evaluate canopy greenness, plant biomass and as an indicator of plant health and vigour. The methodology, relevance and benefits of using this technology in crop protection trials are currently unclear. A handheld Greenseeker® (N-tech Industries, USA) was used to record NDVI on a range of trials from 2008-2011 to establish whether crop sensing could replace visual assessments for disease and enable yield prediction. NDVI readings were compared against other parameters measured in the trials, such as disease scores, green leaf area percentage and yields. In some trials the NDVI followed similar trends to disease, green leaf retention and yields. However, in other cases where clear treatment effects were recorded through visual or yield assessments, there were no differences in NDVI between the treatments. As NDVI can be affected by a number of factors it was concluded that crop sensing technology can be used as an additional objective measurement in conjunction with standard assessment practice but without further investigation cannot replace traditional assessment methods.
Copyright © 2011 New Zealand Plant Protection Society (Inc.).