Search results for "wt"
showing 10 items of 5424 documents
Climatic signals of tree-ring in Quercus gussonei (Borzì) Brullo in the Mediterranean region
2015
Change in growth is among the primary response of trees to environmental variation. Tree-rings contain a wealth of information related to the climatic conditions. A dendroclimatic study on Quercus gussonei (Borzì) Brullo was carried out in the Nature Reserve of “Bosco della Ficuzza, Rocca Busambra, Bosco Del Cappelliere, Gorgo Del Drago” (southern Italy). Q. gussonei is an endemic deciduous oak and thermophilous form of Quercus cerris L. that is found only in Sicily, although with clear sign of decline. The knowledge of ecology of this species should help to establish criteria for forest conservation in the Mediterranean region. For definining the ecological character and understanding the …
INFLUENZA DEL CLIMA SULLA CRESCITA DEL SUGHERO IN SOPRASSUOLI PRODUTTIVI SICILIANI.
2009
Abstract: Cork oak (Quercus suber L.) is usually dominant in silvopastoral systems in many areas of Sicily, where the trees are debarked periodically for cork production. In spite of the importance of cork and cork oak stands in Sicilian forests and the potential economic scenarios, few research works have been carried out on these systems. Given the importance of cork thickness in cork quality evaluation, the main objective of this work is to study cork growth in cork oak productive stands spread on the north (Nebrodi Mountains) and south-east (Iblei Mountains) of Sicily. Image analysis techniques were used on cork surfaces of transverse sections of planks to measure cork rings. Dendrochro…
An alternative set of test to bioassay for bioinsecticides
2010
The development of an assay to determine insecticidal properties for either biological and conventional plant protection products plays an important role on the early screening of potential pathogens or derived toxins candidates. The standard methods for the evaluation it has been by bioassay, especially determination of LD50 or LC 50 requiring the use of relatively large numbers of insects and toxin tests. There are several problems connected with these bioassays: availability of insects and in the right life stage, mass producing the candidate species, preparation, reproducibly and costs relative to intensive manpower. These aspects are really important especially when bio-insectides shou…
Interactions between Bacillus amyloliquefaciens AG1 and Aspergillus spp. contaminating food and feedstuffs
2022
Aspergillus is a widespread fungal genus contaminating and degrading food and feeds mostly during storage. Some species can also produce carcinogenic mycotoxins harmful for human and animal health. In this study, Bacillus amyloliquefaciens AG1 (BaAG1), active against fungal pathogens was evaluated by in vitro tests against seven Aspergillus species belonging to six Aspergillus sections. After 7 days of incubation at 25°C, mycelial growth of all fungal species was reduced from 46.53% to 60.92%, compared to the controls. The inhibitory effect of BaAG1 cell-free culture filtrate was tested by turbidimetric measurements by using ScanReady P-800 that allow the automatic and continuous monitoring…
Meat production from dairy breed lambs due to slaughter age and feeding plan based on wheat bran
2019
This experiment aimed to investigate the possibility to increase the carcass weight of dairy breed lambs and produce moderate-fat meat by applying inexpensive feeding strategies based on restriction and through the use of a fibrous byproduct such as the durum wheat bran (DWB). Sixty-five 45-day-old lambs of the Valle del Belice breed, divided into 6 groups, were fed alfalfa hay supplemented with concentrate feeds including DWB at 0% or 20% (DWB0, DWB20), supplied ad libitum (L) or restricted at 75% (R), and slaughtered at 90 or 120 days of age. The groups were as follows: DWB0-90L (n = 14), DWB20-90L (n = 14), DWB0-120R (n = 10), DWB20-120R (n = 9), DWB0-120L (n = 9), DWB20-120L (n = 9). Th…
Microwave effects on germination and growth of radish (Raphanus sativus L.) seedlings
2002
Germination of radish seeds was delayed and reduced by low-power microwave exposure at 10.5 and 12.5 GHz. Irradiation decreased also hypocotyl growth rate. These effects were increased by rising of the microwave power and by the vertically polarised electromagnetic field. When the irradiation was suspended the seedling growth recovered.
Fungal biodiversity in old-growth forests of Sicily: preliminary results
2014
According to several authors an old-growth forest in Italy is a natural forest in which human disturbance is absent or negligible, and in which natural dynamics create a mosaic of all the forest regeneration phases, including the senescing one. Such phase is characterized by large old trees, deadwood (snags logs and coarse woody debris) and a vascular plant species composition that is consistent with the bio-geographical context and it includes highly specialized taxa related to the small-scale disturbance and the microhabitats resulting from structural heterogeneity. Unmanaged forests are the main refugee for rare and endangered species, including fungi. In Sicily, 472 hectares were recogn…
INVESTIGATION ON OLD-GROWTH FORESTS OF SICILY: PRELIMINARY RESULTS
2014
Old-growth forests are natural forests that have developed over a long period of time, without experiencing severe, stand-replacing disturbance a fire, windstorm, or logging. According to UNEP/CBD/SBSTTA definition, an old-growth forest is a primary or a secondary forest which has achieved an age at which structure and species normally associated with old primary forests of that type have sufficiently accumulated to act as a forest ecosystem distinct from any younger age class. In a thematic contribution to the National Biodiversity Strategy, the authors report the following definition of Italian old-growth forests: Forest in which human disturbance is absent or negligible, and in which nat…
Floristic, phenological and chorological differences in the annual vegetation of Sardinia.
2007
The therophytic flora of Sardinia has been split into four main groups, basing on the ecologic requirements of species. The following groups have been recognized: flora of dry entisoils, flora of periodically swampy or submerged entisoils, flora of coastal sites, flora of fields, road edges and human settlements. Either, most frequent or exclusive species were ascribed to each group. A species was considered “exclusive” when its relative frequency outside a given group was estimated ≤10%. Differences have been highlighted within the groups, dealing with chorology, growth form, flowering time, colour of flowers, pollination and seed dispersal strategies.
Biological characteristics of three Brachyuran crab species in the Lagoon of Elbibane, South-Eastern Tunisia
2016
This study is a first contribution to the knowledge of the biology of three crab species, Carcinus aestuarii, Eriphia verrucosa and Pachygrapsus marmoratus, occurring in the intertidal zone of Elbibane lagoon, south-eastern Tunisia. A total of 1264 individuals from the three brachyuran species were collected monthly from April 2010 until March 2011 and their reproduction and growth parameters were determined. The seasonal distribution of carapace width showed for the three species that males have always a greater size than females. The length-weight relationship showed in the three species a negative allometry in males, and in non-ovigerous females. The von Bertalanffy growth model (VBGF) p…