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Image analysis a new tool for pips morpho-colorimetric measurements of the Sardinian landraces of Vitis vinifera L
No full textSardinia is characterized by a huge number of cultivars traditionally considered as landraces (Lovicu 2007). This variability could be the result of an heterogeneous origin characterizing the Sardinian grapevine platform. Some of these cultivars are considered to be the product of different events, such as direct domestications from local wild grapes and others could have been imported from elsewhere. The Sardinian grapevine germplasm could also have been enriched through breeding events among local varieties and wild plants. This is the result of the ancient and rich history of viticulture of Sardinia, an island that has been colonised by different populations, some with their specific grapevine varieties and viticultural techniques (De Mattia et al. 2007).
Among the autochthons landraces of Sardinian Vitis vinifera L. subsp. vinifera, some accessions from different varieties, were collected during three years (2005-2006-2008) in the experimental fields of Agricultural Research Agency of Sardinia (AGRIS) – Ussana (CA) and stored at AGRIS – Uta (CA).
The pips images were acquired at the Germplasm Bank of Sardinia (BG-SAR) using a flatbed scanner, and successively analysed at the Stazione Consorziale Sperimentale di Granicoltura per la Sicilia (SSG) with a specifically developed macro VITIS.mcr based on Image Analysis software KS 400.
The morpho-colorimetric data and elliptic Fourier descriptors obtained, were elaborated by Linear Discriminant Analysis to build a statistical classifier able to identify the landraces through pip traits (Bacchetta et al. 2008).
Moreover, expected results consist to draw phyletic relationship between Sardinian landraces and some archaeological pips, founded inside a Phoenician-Punic amphora (IV-III B.C.) on the Coltellazzo (Pula) island seabed, close to Cagliari
Morphological characterisation of Vitis vinifera L. seeds by image analysis and comparison with archaeological remains
No full textIn archaeobotanical studies, the taxonomic classification of diaspores has usually been done by simple morphological observation and visual comparison with ex situ collections of seeds, although the use of biometric indices has often proved to be a powerful approach in the taxonomic studies of the genus Vitis as well as for the species attribution of archaeological remains. Using image analysis techniques, seeds from two Sardinian archaeological sites, the pre-Nuragic and Nuragic complex of Sa Osa in central-western Sardinia, attested as the oldest Sardinian archaeological site with remains of Vitis seeds, and the Isola di Coltellazzo in southwest Sardinia, were selected and characterized on the basis of morphological features and Elliptic Fourier Descriptors. Moreover, seeds of five modern populations of V. vinifera ssp. sylvestris collected from southwest Sardinia and the seeds of 41 cultivars of V. vinifera ssp. vinifera mainly from southern and central-western Sardinia were also analysed by computer image analysis. The obtained data were used to implement a database of biometric parameters and to compare the unknown archaeological seeds with the characterized recent seeds, using Linear Discriminant Analysis. The similarity of the archaeological seeds to V. vinifera ssp. vinifera cultivars rather than to V. vinifera ssp. sylvestris populations could allow it to be stated that, between the Middle and Final Bronze Age, varieties very close to modern V. vinifera ssp. vinifera were already being used to produce wine and/or to be preserved for foodstuffs. Moreover, the better matching of the archaeological seeds to white grapes rather than black grape cultivars could indicate the origins of the traditional cultivation of white grapes in these regions of Sardinia
Rootstock effects on postharvest physiological and pathological behaviour of ‘Avana’ mandarin
No full textHydrogen Re-Embrittlement of Aerospace grade High Strength Steels
Get PDFHydrogen Re-Embrittlement on anodically coated high strength steels is a relevant risk for aerospace structures due to the possibility of hydrogen uptake during the operative life of the components. AISI 4340 and Maraging 250 unnotched tensile specimens were subjected to SSRT in order to evaluate the influence of test environment on time to failure. Fracture surfaces were examined by SEM analysis to evaluate the degree of embrittlement and to correlate it with hydrogen diffusivity of the tested steels
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