A second record of Aedes (Stegomyia) albopictus (Diptera : Culicidae) in Malta

The presence of Aedes albopictus (Skuse, 1894) was recently confirmed in Malta (Gatt et al., 2009). Three more adult female mosquitoes were caught indoors by the author from another locality (Marsascala) located in east Malta, and identified from morphological features. This is the second time this species has been recorded for the Maltese archipelago and represents an addition to the nine previously recorded Culicidae mosquito species from the Maltese Islands. Since the species is a known vector for several serious diseases including dengue fever, its occurrence in the Maltese islands needs to be noted by the Health Authorities and measures to contain its spread and/or prevent its establishment, undertaken.peer-reviewe

A vulnerability index for successful eradication of IAPs targets interventions at their most vulnerable stages

Invasive alien plant species (IAPs) are non-native plant species whose introduction and spread outside their natural range poses a threat to biodiversity. Their removal is often financially and environmentally costly from repeated interventions. Tackling IAPs at their most vulnerable stages can be a cost-reducing and effective strategy. A vulnerability index has been devised to plan an IAPs removal strategy based on attacking the most vulnerable stages of a species and focuses on the ease and effectiveness of removing aerial and root biomass as well as propagules. The need for repeated interventions is also factored in the vulnerability index since this forms part of the weakening strategy.peer-reviewe

Seed germination reports for five coastal and inland species from the Maltese Islands

This study investigated seed germination in five indigenous species of plants in the Maltese Islands, predominantly occurring in coastal garrigue habitats but also inland, namely Drimia maritima, Periploca angustifolia, Asparagus aphyllus, Myrtus communis, and Pancratium maritimum. Different germination protocols were tested for one or more populations, namely: four different temperature regimes - constant 15, 20 and 25°C as well as alternating 23.5/15°C; three different photoperiods, 12/12, 16/8 and 0/24 light/dark. The best germination results for each species are provided and additional notes on the species and germination behaviour are also given.peer-reviewe

Use of Suillus collinitus to increase survival rate and resilience of transplanted Pinus halepensis seedlings in habitat restoration practices

In-situ conservation is considered the best way to preserve biodiversity where multiple species can persist with all their natural ecological interactions. The latter element is often ignored. Criticalities can arise when ex-situ grown plants are translocated in-situ without their natural soil microbial associations, especially where abiotic stresses can be severe. Mycorrhizal Fungi (MF) provide several benefits to plants and ecosystem in which are present. The aim of the project was to investigate the use of indigenous MF to enhance acclimatization and survival of exsitu grown plants translocated for habitat restoration. The seeds of Pinus halepensis Mill. as well as sporocarps of naturally associated indigenous MF Suillus collinitus (Fr.) Kuntze (1898), were collected from Natura 2000 sites in the Maltese Islands. P. halepensis seeds were germinated under greenhouse conditions. S. collinitus was inoculated at sowing and seedling stage by placing fragments of the ripe sporocarps in the P. halepensis seedling trays. All the mycorrhized plantlets produced have been reintroduced into selected area of Natura 2000 in the Maltese Islands as part of SiMaSeed restoration project. Such MF inoculation actions can help to enhance restoration and resilience of habitats to reduce biodiversity loss.peer-reviewe

Use of morphocolorimetric analysis to monitor germination success of hydroprimed seeds of Coronilla valentina subsp. glauca (Fabaceae)

This research aimed to investigate if the germination rate of Coronilla valentina seeds (Fabaceae) increased when subjected to extended hydro-priming. Analysis of hydroprimed seeds was carried out by using morphocolorimetric analysis to characterise the imbibition at different hydration time intervals. Seeds that had not been hydro-primed represented the untreated control. Seed swelling is a reliable and time-efficient method to measure seed imbibition, yet a poor predictor of seed germination success. Timing and temperature of the hydropriming treatment influence the germination rate of C. valentina subsp. glauca, with the optimum hydropriming treatment, was found to occur within a 72h period following the 75°C to 25°C treatment.peer-reviewe

The effect of alloying elements on the properties of pressed and non-pressed biodegradable Fe–Mn–Ag powder metallurgy alloys

Current trends in the biodegradable scaffold industry call for powder metallurgy methods in which compression cannot be applied due to the nature of the scaffold template itself and the need to retain the shape of an underlying template throughout the fabrication process. Iron alloys have been shown to be good candidates for biomedical applications where load support is required. Fe–Mn alloys were researched extensively for this purpose. Current research shows that all metallurgical characterisation and corrosion test on Fe–Mn and Fe–Mn–Ag non pre-alloyed powder alloys are performed on alloys which are initially pressed into greens and subsequently sintered. In order to combine the cutting-edge field of biodegradable metallic alloys with scaffold production, metallurgical characterisation of pressed and non-pressed Fe, Fe–Mn and Fe–Mn–Ag sintered elemental powder compacts was carried out in this study. This was performed along with determination of the corrosion rate of the same alloys in in vitro mimicking solutions. These solutions were synthesised to mimic the osteo environment in which the final scaffolds are to be used. Both pressed and non-pressed alloys formed an austenite phase under the right sintering conditions. The corrosion rate of the non-pressed alloy was greater than that of its pressed counterpart. In a potentiodynamic testing scenario, addition of silver to the alloy formed a separate silver phase which galvanically increased the corrosion rate of the pressed alloy. This result wasn't replicated in the non-pressed alloys in which the corrosion rate was seen to remain similar to the non-silver-bearing alloy counterparts.peer-reviewe

Use of waste polystyrene as feed for mealworms (Tenebrio molitor)

This study aimed to determine what percentage of the feed provided to the mealworm larvae of Tenebrio molitor (MWL) could be substituted by polystyrene (PS) whilst retaining mealworm viability. The survival and growth rates, as well as the general performance of the larvae, were followed for a 6-week duration. Four test groups in three independent replicates of MWL, each with 300 larvae at the 8th instar, were fed on varying PS-bran percentages for six weeks under standard growth environment conditions. The four feeding regimes were 0, 50, 75 and 100% PS. The remainder of the feed for the 0, 50 and 75% groups was wheat bran. A 5g carrot supplement was provided for all groups weekly. The mealworms were monitored for mortality, percentage weight gain (%WG) and percentage length gain (%LG), and changes in their lipid and protein content at the end of the 6-week trial. Feeding solely PS did not provide the best degradation of PS, with only 27.39% degradation in six weeks. The 75% PS treatment had the lowest %PS consumption at 21.74%. The best alternative was to provide a feed consisting of 50-50 PS-wheat bran supplemented with carrots giving the highest %PS consumption at 31.06%. Furthermore, over six weeks, the 50% PS treatment larvae had the best %LG and %WG at 47.1% and 278.6%, respectively. By comparison, the 100% PS treatment achieved a %LG and %WG of 36.6% and 205.4 respectively. Mortalities of the 50% PS treatment were of 54.7%, similar to the 75% PS group, whilst, for the 100% PS, mortalities were 73.89%. The control group achieved the lowest mortalities at 22.78%. An additional test was conducted to investigate if a diet consisting of 50% PS significantly affected the protein and lipid content of the MWL compared to the control group. Analysis showed a statistically significant difference in protein content, with the 50% PS diet resulting in a higher protein content of 56.49% and 25.51 % lipid content, on a dry matter basis, when compared to the control group. In conclusion, the 50% PS treatment larvae gave the best larval growth and survival rates out of the three treatments with PS provided in their diet, whilst the 100% PS gave poor results as PS degradation was not as efficient in this test group. A better approach to making use of waste PS is actually to provide the PS as part of a diet supplemented with natural feeds, such as wheat bran and carrots. For the commercialising of this concept, further studies need to be conducted.peer-reviewe

Trichoderma in the Maltese Islands

This study assessed presence of Trichoderma spp. in the Maltese Islands. Isolates were identified using dichotomous keys and DNA barcoding. Ten distinct isolates were obtained from different soils and other substrates, and were identified as T. virens, T. citrinoviride, T. gamsii, and, in the former T. harzianum species complex, T. breve, T. afroharzianum and T. atrobrunneum. Five out of these six fungi are reported for the first time in the Maltese Islands, and T. brevis is reported for the first time in Europe.peer-reviewe

An updated checklist of wood decay fungi in the Maltese Islands

Wood-decaying fungi are very important study subjects for their potential biotechnology applications. They can also create structural damage to wooden structures and to trees, especially older ones with very low level of fitness. White-rot fungi (WRF) are able to degrade lignin efficiently through ligninmodifying enzymes, in contrast to brown-rot fungi (BRF) which can predominantly degrade cellulose and hemicellulose through cellulasedegrading enzymes. Soft-rot fungi (SRF) differ from brown-rot and whiterot by growing mainly inside the S2 layer of the cell wall in wood forming tissue and colonize via the wood rays. Studies of wood decay fungal diversity on trees growing in the Maltese Islands are limited to incomplete records described by handful of authors. The aim of the project was to provide an updated checklist of confirmed records of wood decay fungi occurring on indigenous and exotic phanerophytes.peer-reviewe

A multitrophic culture system for the production of black soldier fly larvae (Hermetia illucens)

A multitrophic system involving mealworm larvae (MWL) and black soldier fly larvae (BSFL) was developed to transform kitchen waste into usable biomass. MWL, fed mainly on kitchen waste, reached an average prepupal length of 2.4cm, fresh weight of 0.12g and protein and lipid content (dry matter) of 44.2% and 16.5% respectively, with an average specific growth rate (SGR) of 2.2%/day and a feed conversion ratio (FCR) of 7.9. The frass generated by the MWL was collected and subsequently fed to the BSFL for an average period of 21 days. On average each MWL, weighing about 0.13g, produced 0.14g of frass over an average period of 97 days. Different batches of BSFL, fed on a variety of feeds, including the MWL frass, kitchen waste and oats, had an average prepupal length of 1.3cm, fresh weight of 0.16g and protein and lipid contents (dry matter) of 41.4% and 26.3% respectively, with an average SGR and FCR of 4.3%/day and 8.9 respectively. BSFL fed MWL frass only obtained some of highest SGR values and the best FCR, with one group achieving 7.5%/day and 2.9 respectively. The amount of frass generated by the MWL, a total of 646g, was capable of sustaining 253.0g of prepupal stage BSFL. This preliminary investigation has demonstrated that a multi-trophic production system using kitchen waste-fed MWL frass to feed BSFL is feasible. Further studies should be carried out to see if the multitrophic concept can be exploited as a production approach.peer-reviewe