Image-based remote approach of Canola yield modelling with cumulative
temporal ground cover for precision agronomy
Abstract
Agronomic technological advancements provide more precise means to
establish methodologies that can estimate yield response in many
different ways. We are experimenting with a new image-based technique to
predict the yield response of Canola using the rate of ground cover
accumulation. Our trial was composed of row spacing and seeding rate as
factors that influence the growth and the spatial distribution to
evaluate its influence on the yield. Using the Visible Band Difference
Vegetation Index (VDVI) from digital images, we estimated the ground
cover and modelled the change over time. We regressed ground cover
accumulation and integrated the function to calculate the area under the
curve to regress against yield. Preliminary analysis indicates that the
green ground cover accumulation overtime is sufficiently correlated with
the yield (F=168.1, p=2.2e-16, R2=0.4694). Further, our results suggest
the amount of green ground cover accumulation over time is dependent on
the seeding density and row spacing. The analysis shows the higher
seeding densities, 40 plants/m2 and above, acquire biomass rapidly, and
the most stable yield predictions with ground cover are likely reached
at similar plant densities. The most stable yield predictions
in-relation to row spacing obtained from either 0.3m, 0.45m or 0.6m
spacing (R-squares 0.94, 0.93, and 0.89, respectively). We are further
experimenting to understand what growth period of the crop is most
suitable for ground cover based yield predictions. Our primary target is
to develop a high throughput image-based methodology to estimate the
yield response using the ground cover accumulation rate for on-farm
precision agronomy.