title: Grape colour phenotyping: development of a method based on the reflectance spectrum.
abstract: BACKGROUND
  The colour of fruit is an important quality factor for cultivar classification and phenotyping techniques. Besides the subjective visual evaluation, new instruments and techniques can be used.
  
  
  OBJECTIVE
  This work aims at developping an objective, fast, easy and non-destructive method as a useful support for evaluating grapes' colour under different cultural and environmental conditions, as well as for breeding process and germplasm evaluation, supporting the plant characterization and the biodiversity preservation.
  
  
  METHODS
  Colours of 120 grape varieties were studied using reflectance spectra. The classification was realized using cluster and discriminant analysis. Reflectance of the whole berries surface was also compared with absorption properties of single skin extracts.
  
  
  RESULTS
  A phenotyping method based on the reflectance spectra was developed, producing reliable colour classifications. A cultivar-independent index for pigment content evaluation has also been obtained.
  
  
  CONCLUSIONS
  This work allowed the classification of the berry colour using an objective method.
authors.affiliation: Università degli Studi di Milano, CIRIVE - Centro Interdipartimentale di ricerca per l'innovazione in Viticoltura ed Enologia, via Celoria 2, I-20133, Milano, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Rustioni
authors.forename: Roberto
authors.initials: R
authors.lastname: Basilico
authors.forename: Simone
authors.initials: S
authors.lastname: Fiori
authors.forename: Alessandra
authors.initials: A
authors.lastname: Leoni
authors.forename: David
authors.initials: D
authors.lastname: Maghradze
authors.forename: Osvaldo
authors.initials: O
authors.lastname: Failla
mesh_terms: D003116:Color; D015203:Reproducibility of Results; D013057:Spectrum Analysis / Q000379:methods*; D027843:Vitis
keywords: Colour characterization; biodiversity; grapes; high-throughput methods; phenotype; pigment content anthocyanins