OAR@UM Collection:

The valorisation of the indigenous grapevine variety, Gellewza, through tissue culture

2021-07-14T08:01:05Z

Title: The valorisation of the indigenous grapevine variety, Gellewza, through tissue culture Abstract: The production of secondary metabolites in tissue culture has been considered as an alternative to the cultivation and harvesting of crops intended for this purpose. The present study was aimed at the production of callus derived from a Maltese indigenous variety, Gellewza, and then inoculated onto plant growth regulators enriched Murashige Skoog (MS) media to determine whether metabolites are produced in vitro as well as to determine the best combination of plant growth regulators needed for the production of these metabolites. The Gellewza material was obtained from certified and potential vineyards. Cuttings were tested for common grapevine viruses, forced to produce shoots and following surface sterilisation, explants were allowed to acclimatise on MS medium. Callus production was induced at this stage, and a Gellewza strain with a high callus yield was selected for further studies. Callus was weighed and placed in different combinations of plant growth regulators. The resultant cultures were allowed to develop and the final callus was assessed for the presence of metabolites. From results obtained, it was observed that the best callus production was obtained by auxin enriched MS media. In fact indole acetic acid and indole acetic acid /6-benzylaminopurine enhanced biomass accumulation (3.036g and 3.391 g) as opposed to the others (<1.973g). On the other hand parameters showing the presence of flavonoids (tonality), particularly anthocyanins and total polyphenols, were optimum in the presence of cytokinins particularly 6-benzylaminopurine (Tonality (3.799), anthocyanins (24.1 mg/kg), total polyphenolic content (0.142%). This is the first study to describe the production of polyphenols in Gellewza callus cultures. The findings may stimulate further research along this direction. Description: M.SC.RURAL SCI.

The olive tree in the Mediterranean basin : origin and history

2016-09-28T09:18:53Z

Title: The olive tree in the Mediterranean basin : origin and history Abstract: The primary objective of this dissertation is to examine and explore the tight relationship that existed since thousands of years between the Olea europaea (Olive tree) and the different cultures of Mediterranean region. This relationship initiated during the Early Neolithic Period and continued to flourish and prosper through the ages, although the Mediterranean was conquered by different civilizations and cultures. The olive tree is synonyms to the Mediterranean region since it grows naturally. The Mediterranean Basin offers optimal climatic conditions for its cultivation and as a result the Olea europaea was placed at the heart of the Mediterranean. Witness of this importance are the numerous stone olive presses and crushers that were discovered in almost all the regions of the Mediterranean. The presence of the Olea europaea has marked both the landscape of the entire Mediterranean region and the different cultures and the people of Mediterranean. The tree is “mythical and sacred” and is deeply associated with the traditions of the Mediterranean. The Olea europaea has influenced the life of the people of the region in such a way that an "olive tree civilisation" was created. In the Maltese Islands the olive tree was introduced by the Phoenician seafarers in the 1st millenium B.C. and the cultivation extended its great importance during the Roman Period, when the olive industry became very important to the Mediterranean and the Maltese Islands. Evidence of the importance of the olive tree and olive oil in ancient times is shown in local village names such as Żejtun, Ħaż-Zebbuġ and Birżebbuġa. The findings of this dissertation also demostrate that in recent years the cultivation of the olive tree and the production of olive oil has grown remarkably, as a result of modern techniques in both the cultivation of the Olea europaea and in the production of olive oil. Ongoing investigations and trails, together with the revitalisation of old Olea europaea cultivars and varieties are developing and remodeling the olive industry both in the Mediterranean and the Maltese Islands. Description: DIP.AGRICULTURE

Overview of fig tree cultivation in the Maltese islands

2016-09-28T09:44:46Z

Title: Overview of fig tree cultivation in the Maltese islands Abstract: The fig tree, Ficus carica, originated in the Middle East and has been under cultivation since at least 11,000 years during the Neolithic period. It is well adapted to the Mediterranean conditions and grows well in the Maltese Islands. More than 30 different varieties of fig trees used to be cultivated in Malta but this number has now decreased. The fig tree produces an early fruit which matures around mid-June and is known as "bajtar ta' San Gwann", which are plump and tender. Late figs known as "tin" are produced from the same tree but mature some six weeks after the early figs have finished. Late figs undergoes an important process of pollination known as caprification. From the caprifig a tiny insect, Blastophaga pesenes emerges and enters the late fig to pollinate the fruit. The fig fruit is rich in several minerals and is a good source of antioxidant which helps in maintaining good health and wellness. Moreover, the fruit possess a high fibre content which nourish and tone the intestines and act as a natural laxative. Regular pruning of fig trees is a prerequisite for better fruit production, decreased incidence of pests and diseases and easier harvesting. Fig trees host more than 30 insect pests and diseases of which some can be detrimental to the tree. The most important pest is a bark beetle, Hypocryphalus scabricollis, native of the Indian sub-continent and reported from Malta in 2009. This beetle has been decimating fig trees in Malta and Gozo for these last 8 years and more than 50% of such trees have already been killed. Description: DIP.AGRICULTURE

The effect of a hydroponic system on mint and rosemary potted plants

2017-07-18T10:09:10Z

Title: The effect of a hydroponic system on mint and rosemary potted plants Abstract: In this project, one can find the effect of salinity on mint and rosemary in a hydroponic controlled system. To show these differences some lab tests were done, starting with the chlorophyll tests, Polyphenol tests on the mint and rosemary yield and roots and Heavy Metal Analysis on yield, roots and water used in the system. The experiments showed some interesting differences from one treatment to the other and some other differences between the different herbs. While growing the herbs some differences like size and rate of development were recorded as well and these were related to the experiment results as well. A curious thing that came out is that rosemary had a hard time to live in a hydroponic system and this is shown in the polyphenol results, the polyphenols where relatively high compared to mint another interesting think is that rosemary didn’t produce any roots during the growing , on the other hand chlorophyll results showed that mint was performing at its best especially in the Medium salinity treatment, this is visible because of the low mortality rate shown here and later in the results and discussion section. The Report title is ‘The Effect of a Hydroponic System on Mint and Rosemary potted plants’ and in this report I discussed some aspects of hydroponics regarding mint and rosemary that can be found further on in the report, these aspects are the Heavy metal Absorption and deposition from and in the plant, Chlorophyll content in the yield and polyphenols. After doing this report I may conclude that mint can grow better than Rosemary in hydroponics and the best water and fertiliser treatments will be between 450 - 310 x10μs Conductivity, 140 - 200 x10ppm Parts per Million and pH that varies from 5 to 6.5. More detailed results and discussion can be found later on in the report. Description: DIP.AGRICULTURE