Near infrared (NIR) hyperspectral imaging and multivariate image analysis to study growth characteristics and differences between species and strains of members of the genus fusarium
Date
2012-08
Authors
Williams, Paul J.
Geladi, Paul
Britz, Trevor J.
Manley, Marena
Journal Title
Journal ISSN
Volume Title
Publisher
SpringerLink
Abstract
Near-infrared (NIR) hyperspectral imaging was
used to study three strains of each of three Fusarium spp.
(Fusarium subglutinans, Fusarium proliferatum and Fusarium
verticillioides) inoculated on potato dextrose agar in
Petri dishes after either 72 or 96 h of incubation. Multivariate
image analysis was used for cleaning the images and for
making principal component analysis (PCA) score plots and
score images and local partial least squares discriminant
analysis (PLS-DA) models. The score images, including
all strains, showed how different the strains were from each
other. Using classification gradients, it was possible to show
the change in mycelium growth over time. Loading line
plots for principal component (PC) 1 and PC2 explained
variation between the different Fusarium spp. as scattering
and chemical differences (protein production), respectively.
PLS-DA prediction results (including only the most important
strain of each species) showed that it was possible to
discriminate between species with F. verticillioides the least
correctly predicted (between 16 and 47 % pixels correctly
predicted). For F. subglutinans, 78–100 % pixels were correctly
predicted depending on the training and test sets used.
Similarly, the percentage correctly predicted values of F.
proliferatum were 60–80 %. Visualisation of the mycelium
radial growth in the PCA score images was made possible
due to the use of NIR hyperspectral imaging. This is not
possible with bulk spectroscopy in the visible or NIR
regions.
Description
Publication of this article was funded by the Stellenbosch University Open Access Fund.
The original publication is available at http://link.springer.com/journal/216
The original publication is available at http://link.springer.com/journal/216
Keywords
Near-infrared hyperspectral imaging, Fusarium, PCA, PLS-DA, Classification gradients
Citation
Williams, P. J., Geladi, P., Britz, T. J. & Manley, M. 2012. Near-infrared (NIR) hyperspectral imaging and multivariate image analysis to study growth characteristics and differences between species and strains of members of the genus fusarium. Analytical and bioanalytical chemistry, 404, 1759-1769, doi:10.1007/s00216-012-6313-z.