Resumen
Aim of study: Umbrella or stone pine (Pinus pinea) nuts are one of the most valuable and expensive non-wood forest products in Portugal. The increasing market and landowner's interest resulted on a high expansion of plantation areas. This study tests the feasibility of using tomography to characterize pine cones and nuts.Area of study: The research was carried out in pine stand, with nine years, grafted in 2011, on Herdade of Machoqueira do Grou, near Coruche, in Portugal?s central area.Material and Methods: Starting in June 2015, ten pine cones in their final stage of development, were randomly monthly collected, and evaluated with tomography equipment commonly used in clinical medicine, according to Protocol Abdomen Mean. A sequence of images corresponding to 1mm-spaced cross-sections were obtained and reconstructed to produce a 3D model. The segmented images were worked using free image processing software, like RadiAnt Dicom Viewer, Data Viewer and Ctvox.Main results: The cone?s structures were clearly visible on the images, and it was possible to easily identify empty pine nuts. Although expensive, tomography is an easy and quick application technique that allows to assess the internal structures, through the contrast of materials densities, allowing to estimate pine nut?s size and empty nut?s proportion. By analysis of ninety images, it was obtained, an estimated mean value of 25.5 % empty nuts.Research highlights: Results showed the potential of tomography as a screening tool to be used in industry and research areas, for analysis and diagnostic of stone pine cone?s structures.Keywords: pine cone; pine nuts; stone pine; tomography; CAT.Abbreviations: CAT: computerized axial tomography; 3D: three dimensional; HU: Hounsfield Units.