Nematology (2000) 2, p. 760 (Heath et al.)

William Heath, Patrick Haydock, Andrew Wilcox and Kenneth Evans (2000)
The analysis of light reflected from the potato crop as a diagnostic assay for infection by potato cyst nematodes
Nematology 2 (7), 760-760
Presented at the 25th International Nematology Symposium, Herzliya, Israel, 2-7 April 2000
Abstract: Potato cyst nematodes invade the roots of developing potato plants, damaging the root structure and reducing the uptake of nutrients by the plant. Current methods of determining PCN population densities are both expensive and time consuming, providing only estimates of the average population levels within fields without measurement of variability or means of identifying developing foci of infestation. Nematode infestation may alter both the structure and chemical content of leaves. As each element in a leaf reflects light at different wavelengths, correlation of a change in canopy reflectance with nematode infestation may provide a method of identifying foci of infestation. A hand-held spectroradiometer has been used to record canopy reflectance from potato plants infected with a range of PCN densities. Preliminary results indicate that PCN infestation can be detected by spectral analysis. Spectral readings from a field experiment correlated Normalised Derived Vegetation Index (NDVI) with root invasion (R² = .825, N = 138, cv. Estima) and was supported by a concurrent pot experiment (r² = .866, N = 285, cv. Pentland Dell). NDVI is a broad measure of plant condition and a further experiment is underway to pursue spectral response features specific to PCN infection. Further development of the analysis is envisaged using airborne remote sensing, leading to a comparison of ground and airborne readings with data recorded from a planned series of high resolution, infra-red environmental monitoring satellites.
Database assignments for author(s): Patrick P.J. Haydock

Research topic(s) for pests/diseases/weeds:
surveys/sampling/distribution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Globodera pallida	Potato (Solanum tuberosum)	United Kingdom