https://www.um.edu.mt/library/oar/handle/123456789/102642 Tue, 14 Apr 2026 22:43:14 GMT 2026-04-14T22:43:14Z https://www.um.edu.mt/library/oar/handle/123456789/107495 Title: Impacts on and population trends of Scopoli's shearwater Calonectris Diomedea in the Maltese islands Abstract: The Scopoli’s Shearwater Calonectris diomedea, in Maltese Ċiefa is the subject of this study. A pelagic seabird that breeds in the Maltese islands. Procellariformes, have a long breeding season spanning from late February to late October, laying only one egg each year. Therefore, the long period on land makes this species very vulnerable to predation and disturbance by terrestrial mammals, including humans. This study seek to evaluate this relationship in four study areas. It also looks at the effects of existing legal protection measures on the breeding population of C. diomedea. The breeding colonies that are being discussed are found along the southern sheer cliffs of Malta, the north-western cliffs of Gozo, and on offshore islands like Filfla. There never were any specific studies on the species until 1982 when an extensive study on the breeding biology and ecology of this species was initiated by the present researcher. This study covers a period of 38 years from 1983 to 2020, making use of data collated by the present researcher. A total of 158 study nests were under observation, mainly on the islands of Malta and Gozo as well as on some of the smaller islands, most notably on Filfla island. This present study analyses and presents results on population trends from a sample of four study sites namely, Ħal-Far, Għar Lapsi, Għarb and Filfla. An overall decline in the breeding population, particularly in two colonies: Ħal-Far in Malta and Għarb in Gozo is evident, which is mainly due to direct (killing) and indirect (urbanisation etc.) human activities. The numerous existing policies and legal notices should, in theory, provide adequate legal protection measures to the breeding sites as well as to the species in question. The study highlights the various threats and the lack of protection measures for the protection of these seabirds. The study concludes that at the current rate, based on the results obtained, the ongoing decline is projected to lead to the extinction of Scopoli’s Shearwater from the Maltese islands in less than fifty years’ time. The methodology used and the results attained are put forward as a basis for the conservation of this and other pelagic seabird species breeding in the Maltese islands. Description: M.Sc.(Melit.) Sat, 01 Jan 2022 00:00:00 GMT https://www.um.edu.mt/library/oar/handle/123456789/107495 2022-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/104821 Title: The physicochemical characterisation and morphometric analysis of pomegranates (Punica granatum L.) cultivated in the Maltese Islands Abstract: Punica granatum L. is beloved globally for its comprehensive range of nutritional and nutraceutical constituents. This empirical study aimed to establish the basis of pomegranate cultivation and obtain a holistic representation of the full potential of the ‘fruit of paradise’ as pertaining to the central Mediterranean. Several intrinsic visual, physical, and chemical characteristics were investigated along with the various flowering and fruit maturation stages of 35 different accessions cultivated in 5 distinct regions in the 2021 growing season. The morphological properties of the leaf, flowering buds, blooms, and fruits at 3 ripening stages expressed significant differences as well as similarities between the accessions in most of the parameters investigated. Matured fruits FW ranged between 87 ± 8.06 – 586 ± 88.6 g, longitudinal diameter between 4.86 ± 0.27 – 9.13 ± 0.23 cm, equatorial diameter between 5.29 ± 0.30 – 10.7± 0.37 cm, sphericity between 0.77 ± 0.01– 0.98 ± 0.03, and rind thickness between 2.14 ± 0.03 – 4.33 ± 0.03 mm. 3 types of fruit crowns were expressed, being either closed, opened or semi-opened, while fruits possessed either 6 or 8 sepals, according to the cultivar. It was also concluded that the growing regions and age of pomegranate shrubs appeared not to affect these parameters. Rather, slight variations in development stages, climatic, environmental and cultivation conditions, as well as genetic variability and diversity were responsible. Furthermore, PCA and AHC analysis of the ripened pomegranates generally revealed the distinction between the ‘Santa Rosa’, ‘Unknown’, ‘Acco’, ‘Santa Katarina’, and ‘Ħelu’ cultivars, while almost all the ‘Bullar’, and ‘San Ġużepp’ accessions expressed significant morphological similarities. The pH and TSS increased while TA decreased along fruit maturation, resulting in the majority of local accessions having a moderate (sour sweet to sweet taste) and relative high MI (sweet taste). Colour variation was associated with increased TAC and decreased lycopene, total carotenoids, and total chlorophyll content along the fruit ripening stages. The lowest TPC was recorded in ripened pomegranates ranging between 0.111 – 0.635 % w/w GAE. Overall, the pulp of ripened pomegranates recorded the quantitative descending order of K > Ca > Na > Mg > Fe, and apart from the latter micronutrient, the other macronutrients exhibited a decreased accumulation along fruit ripening. The peel and pulp physicochemical parameters revealed several strong positive and negative correlations, concluding amongst which that MI can serve as an effective estimate for both the TA and pH when comparing local pomegranates. In conclusion, this study revealed that local pomegranate peel exhibits a substantial nutritional potential due to significantly higher TAC (∼ 3.5-fold), TPC (∼ 5.7-fold), lycopene (∼ 5.6-fold), % total carotenoids (> 10-fold), % total chlorophyll (∼ 4.6-fold), Ca (∼ 5.2-fold), Mg (∼ 3.5-fold), K (∼ 3-fold), Na (∼ 1.5-fold), and Fe accumulations than the fresh juice of ripened fruits, meaning that instead of being discarded, this inedible pomegranate part can be sustainably exploited in the food, cosmeceutical, and pharmacological industries. Thus, Maltese-grown pomegranates hold the potential for versatile and holistic utilisation that should be further exploited, not only agriculturally but also as effective alternatives in several important industries. Description: M.Sc.(Melit.) Sat, 01 Jan 2022 00:00:00 GMT https://www.um.edu.mt/library/oar/handle/123456789/104821 2022-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/103007 Title: A physicochemical study on the effects of oak maturation of Ġellewża and Girgentina wines Abstract: Amongst the Maltese indigenous grape cultivars (Vitis vinifera) Ġellewża and the Girgentina cultivars are the best known which is mainly due to the production of their wines with IĠT appellations. At the time of the study, the wines produced for these cultivars were red wines and sparkling Rose’s from Ġellewża and white non-sparkling and sparkling wines from Girgentina. A few Chardonnay-Girgentina blends were also available. Through a physicochemical study of a range of wines produced by local vintners of cultivars, several characteristics emerged about these wines including the high polyphenolic content (established through Folin-Ciocalteu Colorimetric Method), especially in Girgentina relative to other white wines of the world. Spectroscopic analysis revealed anthocyanin content to be very high for a white variety which sheds interest with regards to bioactive compounds content within such wines. Within this study, an innovative method of oak maturation was employed. It entailed using high toast French oak chips (Quercus alba) where finished wines were exposed to the wood in a non-oxidative environment. Through continued physicochemical analysis and sensorial analysis, it was concluded that there was indication of compatibility of oak maturation with these local wines with Ġellewża wines benefitting majorly, being red wines. Moreover, it was established that such a method could benefit wines requiring corrections. The method of oaking used was not stipulated as an alternative to traditional oaking methods but rather a costeffective method that can be used to enhances some wines. This degree was carried out following the award of a Tertiary Education Scholarships Scheme Scholarship. Description: M.Sc.(Melit.) Sat, 01 Jan 2022 00:00:00 GMT https://www.um.edu.mt/library/oar/handle/123456789/103007 2022-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/102700 Title: A preliminary study of the morphology and genetic characterisation of olive cultivars in the Maltese islands Abstract: The use of morphological and genetic characterisation of olive tree cultivars has been widely used internationally by olive producing countries to characterise and identify olive cultivars to create olive germplasm databases. Locally, the literature on olive trees is limited, and a local olive germplasm database is lacking. During this study, sampling of 79 ancient olive trees (from 32 different sites in Malta, Gozo and Comino) was carried out from August 2020 till September 2020 and this was repeated in 2021. Samples were taken from both the canopy and the rootstock of each tree. Samples consisted of 30 leaves from both canopy and rootstock, which were stored at -80°C for genetic testing. Of these, 35 different genotypes were identified, of which four were known olive cultivars belonging to “Nocellara del Belice” Sicilian cultivar, “Lumiaro” Sicilian cultivar, “Ottobratica” Italian cultivar and “Zalmati” Tunisian Cultivar. The remaining 31 genotypes, were unique and not included in the international genotype database of the BeFOre project. Of these, 16 genotypes belong to rootstock and the other 19 belong to the canopy. The 16 rootstock genotypes were not studied further due to the lack of drupes and unviable leaves. The other 19 canopy genotypes were further investigated and morphological studies were carried out on the tree morphology, leaves, drupes and seed pits of the “Leader” cultivar of each genotype. They were characterised and analysed via 13 qualitative and 15 quantitative morphometric parameters through the International Union for the Protection of New Varieties of Plants (UPOV) method. The morphological profiles of the 19 genotypes, were compared to local and international literature and four were found to be identical to the “Bidni”, “Malti”,“ Lumiaro” and “Ottobratica” cultivars. All the other 15 genotypes were found to be unique, both from a morphological and genetic approach. This confirms the usefulness of the morphological profiles in being used as a tool to compare and distingush olive genotypes, and also to back up the genetic results. The morphometric parameters were analysed with One-Way ANOVA and Two-tailed Pearsons correlation by using SPSS v.21. The unique cultivars were compared by morphological parameters via Hierarchical cluster analysis with the Wards method, squared Euclidean distance and depicted via a dendrogram. The SSR marker data analysis for the observed number of alleles (Na), the effective number of alleles (Ne), observed (Ho) and expected (He) heterozygosity estimates and the heterozygous deficiency (F), were calculated by using GenAlEx version 6.5. The Neighbour-joining of the Maltese genotypes and International olive genotypes of the BeFOre database was conducted via MEGA version 7. Description: M.Sc.(Melit.) Sat, 01 Jan 2022 00:00:00 GMT https://www.um.edu.mt/library/oar/handle/123456789/102700 2022-01-01T00:00:00Z