A GER-1500 field spectro-radiometer was used in this study in order to retrieve the necessary spectrum data of the spring potatoes for estimating the spectral vegetation indices (SVI's). A field campaign was undertaken with measurements of LAI, and crop height using the Sun-Scan instrument, acquired simultaneously with the spectroradiometric measurements between March and April of 2009. Several regression models are tested for determining the best 'regression models' that to relate LAI/crop height and SVI's. The results showed that there is a strong statistical relationship between LAI/crop height and SVI's which can be used at the estimation of evapotranspiration (ETc). Direct comparison and validation of proposed models with Landsat image data is also made. The study area was the Mandria Village in Paphos district in Cyprus.© (2010) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.