Monitoring turfgrass species and cultivars by spectral reflectance

Summary Like all modern agriculture sectors, turfgrass production and management is headed towards cost reduction, resource optimization and reduction of the environmental impact. In recent years the development of new technologies has provided new tools for monitoring agricultural crops. In particular, the combined adoption of geographic information systems, global positioning systems, multispectral lenses on board satellites and cartographic techniques allow a large scale management of agricultural resources. This paper reports the results of a trial attempting to evaluate the spectral signatures of several turfgrass species, for future use in satellite monitoring. This experimental study focused on 20 turfgrass species, including perennial ryegrasses, tall fescues, kentucky bluegrasses, bermudagrasses (ecotypes, seeded and vegetatively propagated cultivars) and zoysiagrasses. Various agronomical and biological parameters were studied (quality, colour, dry matter, chlorophyll, carotenoids, nitrogen content) and turfgrass spectral reflectance for all entries was gathered. Results showed that, within the same species, selected vegetation indices are often able to discriminate between different cultivars that have been established and maintained with identical agronomical practices. Evaluation ofthe spectral reflectance of plants using field spectroradiometry provides the possibility to identify different species, especially through the use of hyperspectral proximity and remote sensing.