Origini e diffusione dell’agricoltura in Sardegna: studio dei resti vegetali della preistoria

The main goal of this work is fill in gaps in the existing knowledge on the origins and spread of agriculture in Sardinia through the analyses of archaeological plant remains. Plant use (both domesticated and wild) have allowed exploring the subsistence system of the first farming communities in the island. More specifically, the main goals are: • Identification of the first domesticated plants in Sardinia (cereals, legumes and others) and investigate the pathways and time of agricultural adoption. • Recognizing the wild component in the diet of the first Neolithic communities. • Exploration of agrarian practices (harvesting, crop processing, etc). • Determination the role of Vitis vinifera L., in the past human subsistence. • Develop a model for the adoption and spread of agriculture in the island. In order to accomplish these objectives, plant remains from different sites and periods have been studied. The material considered for this study is composed of seeds, fruits and other plant remains recovered from 12 archaeological sites. As far as recovery techniques, archaeological contexts was systematically sampled following standardized protocols. Soil samples were floated so charred material have been separated from the soil fraction. Once in the lab, plant remains have been examined under the stereomicroscope and identified mainly with the help of a reference collection. Atlas of seed identification as well of specialized bibliography also were used. In addition,morphocolorimetric analyses were performed through image analyses to establish parameters for identification. Data obtained through the scanning of prehistoric seeds were integrated in the BG-SAR database. The study of plant remains have offered the opportunity to explore agrarian practices and crop processing enabling, therefore, a deep insight into the way farming communities manage their crops and use plants for their subsistence going beyond the mere identification of plant species. This research made possible, therefore, to develop a model for the spread of plant cultivation in Sardinia hitherto unknown. The identification of wild plants have facilitated the study of the role of wild resources in human subsistence in Sardinia as a complement to the diet. Furthermore, the diachronic study on plant use have added time depth to the analyses of human use of plants. This work has 6 chapters. Chapter 1 exposes the state of the art on the origins and spread of agriculture in Italy. Chapter 2 presents an overview of the present state of research on prehistoric agriculture in Sardinia during the Neolithic. Chapter 3 presents the results of archaeobotanical analyzes from Chalcolithic period in Sardinia, the analysis have focused on the archaeological site of Canelles. Chapter 4 presents data on agriculture practiced in Sardinia during the Bronze Age, in particular, provides an overview on crop plants (cereals and pulses) during the the different periodizations of the Bronze Age in Sardinia. Chapter 5 presents data obtained from morphological comparisons of grape seeds found in the archaeological site of Sa Osa with the seeds of the modern cultivars and wild grapevine from Sardinia

Morphological Characterization of Fossil Vitis L. Seeds from the Gelasian of Italy by Seed Image Analysis

The discovery of well-preserved fossil Vitis L. seeds from the Gelasian stage in Italy has provided a unique opportunity to investigate the systematics of fossilized Vitis species. Through seed image analyses and elliptical Fourier transforms of fossil Vitis seeds from the sites Buronzo-Gifflenga and Castelletto Cervo II, we pointed out a strong relationship to the group of extant Eurasian Vitis species. However, classification analyses highlighted challenges in accurately assigning the fossil grape seeds to specific modern species. Morphological comparisons with modern Vitis species revealed striking similarities between the fossil seeds and V. vinifera subsp. sylvestris, as well as several other wild species from Asia. This close morphological resemblance suggests the existence of a population of V. vinifera sensu lato in Northen Italy during the Gelasian. These findings contributed to our understanding of the evolution and the complex interplay between ancient and modern Vitis species

Morpho-Colorimetric Characterization of the Sardinian Endemic Taxa of the Genus Anchusa L. by Seed Image Analysis

In this work, the seed morpho-colorimetric differentiation of the Sardinian endemic species of Anchusa (Boraginaceae) was evaluated. In Sardinia, the Anchusa genus includes the following seven taxa: A. capellii, A. crispa ssp. crispa, A. crispa ssp. maritima, A. formosa, A. littorea, A. montelinasana, and A. sardoa. Seed images were acquired using a flatbed scanner and analyzed using the free software package ImageJ. A total of 74 seed morpho-colorimetric features of 2692 seed lots of seven taxa of Anchusa belonging to 17 populations were extrapolated and used to build a database of seed size, shape, and color features. The data were statistically elaborated by the stepwise linear discriminant analysis (LDA) to compare and discriminate each accession and taxon. In addition, the seed morpho-colorimetric differences among coastal and mountainous taxa were evaluated. Considering the ecological conditions, the LDA was able to discriminate among the Anchusa taxa with a correct identification of 87.4% and 90.8% of specimens for mountainous and coastal plants, respectively. Moreover, the LDA of the 17 populations of Anchusa showed a low separation among species and populations within the coastal group, highlighting how the long-distance dispersal by flotation on the sea water surface and the pollination network may influence the similarity patterns observed. In addition, a misattribution was observed for A. crispa ssp. crispa, which was misclassified as A. crispa ssp. maritima in 14.1% of cases, while A. crispa ssp. maritima was misidentified as A. crispa ssp. crispa in 21.1% of cases, highlighting a close phenotypic relationship between these two taxa. The statistical results obtained through the seed image analysis showed that the morpho-colorimetric features of the seeds provide important information about the adaptation and evolution of Anchusa taxa in Sardinia

Predictive method for correct identification of archaeological charred grape seeds: Support for advances in knowledge of grape domestication process

The identification of archaeological charred grape seeds is a difficult task due to the alteration of the morphological seeds shape. In archaeobotanical studies, for the correct discrimination between Vitis vinifera subsp. sylvestris and Vitis vinifera subsp. vinifera grape seeds it is very important to understand the history and origin of the domesticated grapevine. In this work, different carbonisation experiments were carried out using a hearth to reproduce the same burning conditions that occurred in archaeological contexts. In addition, several carbonisation trials on modern wild and cultivated grape seeds were performed using a muffle furnace. For comparison with archaeological materials, modern grape seed samples were obtained using seven different temperatures of carbonisation ranging between 180 and 340°C for 120 min. Analysing the grape seed size and shape by computer vision techniques, and applying the stepwise linear discriminant analysis (LDA) method, discrimination of the wild from the cultivated charred grape seeds was possible. An overall correct classification of 93.3% was achieved. Applying the same statistical procedure to compare modern charred with archaeological grape seeds, found in Sardinia and dating back to the Early Bronze Age (2017-1751 2σ cal. BC), allowed 75.0% of the cases to be identified as wild grape. The proposed method proved to be a useful and effective procedure in identifying, with high accuracy, the charred grape seeds found in archaeological sites. Moreover, it may be considered valid support for advances in the knowledge and comprehension of viticulture adoption and the grape domestication process. The same methodology may also be successful when applied to other plant remains, and provide important information about the history of domesticated plant

Germination of Sardinian black and white Vitis vinifera seeds according to treatments and dormancy factors

Physiological dormancy of Vitis vinifera seeds jeopardises breeding programs and biodiversity evolution. To increase the knowledge on dormancy breaking, seeds of white and black Sardinian grape cultivars (cvs) were exposed to different pre-germination treatments. To shed light on the physiological and structural factors involved in seed dormancy, the contents of oil, abscisic acid, gibberellic acid, 3-indolacetic acid, condensed tannins, and total polyphenols were determined. In addition, sectioned seeds were observed by SEM to determine the morphological and anatomical characteristics. Dormancy break in white, but not in black grape seeds, occurred under almost all imposed pre-germination treatments. Among red cvs, only seeds from ‘Cagnulari’ germinated when kept at 25 °C. Chilling seeds of the white cvs ‘Malvasia sarda’ and ‘Vernaccia di Oristano’ for 30 d resulted in the most effective treatment. Compared to white cvs, seeds of red ones owned 7 times higher levels of abscisic acid however, gibberellic acid content resulted 4 times less. Concerning the coat characteristics, red cv seeds had a thicker cuticle (6-10 μm) than white (4-6 μm) ones, however the most significant diversities were found for the inner integument, where in addition to size variances, palisade cell wall were structurally different

Unearthing Grape Heritage: Morphological Relationships between Late Bronze–Iron Age Grape Pips and Modern Cultivars

The grapevine was one of the earliest domesticated fruit crops and has been cultivated since ancient times. It is considered one of the most important fruit crops worldwide for wine and table grape production. The current grape varieties are the outcome of prolonged selection initiated during the domestication process of their wild relative. Recent genetic studies have shed light on the origins of the modern domestic grapevine in western Europe, suggesting that its origin stems from the introgression between eastern domestic grapes and western wild grapes. However, the origin of ancient grapevines remains largely unexplored. In this study, we conducted an extensive analysis of 2228 well-preserved waterlogged archaeological grape pips from two sites in Sardinia (Italy), dated to the Late Bronze Age (ca. 1300-1100 BC) and the Iron Age (4th and 3rd centuries BC). Using morphometrics and linear discriminant analyses, we compared the archaeological grape pips with modern reference collections to differentiate between wild and domestic grape types and to investigate similarities with 330 modern cultivars. Grape pips from the Late Bronze Age displayed a high percentage of similarity with domesticated grapevines, with a small percentage assigned to wild ones, while the majority of grape pips from the Iron Age were classified as domestic. Discriminant analyses revealed that both white and red grape varieties were cultivated during the Late Bronze and Iron Ages, suggesting a high level of diversification in grape cultivation. Furthermore, a high percentage of archaeological grape pips from both periods showed strong similarities with modern cultivars from the Caucasus and Balkans. This suggests that the great diversity of grapevines present in Sardinia could result from interbreeding between western Asian cultivars and local grapevines that began in the Late Bronze Age. Additionally, a substantial proportion of archaeological grape pips exhibited similar morphometric characteristics to two important Mediterranean grape cultivars: "Muscat à petits grains blancs" and "Garnacha"

Seed Morphology in the Vitaceae Based on Geometric Models

16 páginas, 8 figuras, 6 tablasMorphometric methods based on artificial vision algorithms provide measurements for magnitudes descriptive of seed images (i.e., the length, width, area, and surface circularity index). Nevertheless, their results frequently omit the resemblance of the images to geometric figures that may be used as models. A complementary method based on the comparison of seed images with geometric models is applied to seeds of Vitis spp. The J index gives the percentage of similarity between a seed image and the model. Seven new geometric models are described based on the heart-shaped and piriform curves. Seeds of different species, subspecies and cultivars of Vitis adjust to different models. Models 1 and 3, the heart curve and the water drop, adjust better to seeds of V. amurensis, V. labrusca and V. rupestris than to V. vinifera. Model 6, the Fibonacci’s pear, adjusts well to seeds of V. vinifera, in general, and better to V. vinifera ssp. vinifera than to V. vinifera ssp. sylvestris. Seed morphology in species of Cissus and Parthenocissus, two relatives of Vitis in the Vitaceae, is also analysed. Geometric models are a tool for the description and identification of species and lower taxonomic levels complementing the results of morphometric analysis.This research was funded by Universidad de Salamanca (Programa XIII para la financiación de grupos GIR)Peer reviewe