Search results for "Quercus ilex"

Native and planted forest species determine different carbon and nitrogen pools in Arenosol developed on Holocene deposits from a costal Mediterranea…

2016

In a coastal Mediterranean area, the effects of two native [Quercus ilex (Holm), Alnus glutinosa and Fraxinus oxycarpa (Hygro)] and one planted [Pinus pinaster (Pine)] forest species on both content and quality of organic C and total N pools in Arenosols was assessed. Three soil profiles per each forest cover were opened and sampled. Total N in the organic layers was not affected by forest covers, whereas total organic C ranged from 36.1 to 63.2 Mg ha−1, being organic layers under Hygro those with the highest contents. Total organic C in the first 50 cm of mineral soil was 64 Mg ha−1 under Holm and 36.7 and 37.6 Mg ha−1 under Pine and Hygro, respectively. Soil covered by Holm and Hygro stor…

Effect of methyl jasmonate in gene expression, and in hormonal and phenolic profiles of holm oak embryogenic lines before and after infection with Ph…

2022

The dieback syndrome affecting Quercus ilex and other oak species impels the search for tolerant plant genotypes, as well as methods of plant immunization against such infections. Elicitation treatments can be an effective strategy to activate plant defense response and embryogenic lines represent a promising tool to generate new tolerant genotypes and also to study early markers involved in defense response. The aim of the presented work was to investigate changes in gene expression, and in hormonal and phenolic profiles induced in three holm oak embryogenic lines (ELs) elicited with methyl jasmonate (MeJA) before and after infection with the oomycete Phytophthora cinnamomi, which is the m…

Holocene vegetation and fire dynamics in the supra-mediterranean belt of the Nebrodi Mountains (Sicily, Italy).

2012

High-resolution pollen, macrofossil and charcoal data, combined with accelerator mass spectrometry 14C dating and multivariate analysis, were used to reconstruct Holocene vegetation and fire dynamics at Urio Quattrocchi, a small lake in the supra-mediterranean belt in the Nebrodi Mountains of Sicily (Italy). The data suggest that after 10 000 cal a BP increasing moisture availability supported closed forests with deciduous (Quercus cerris, Fagus sylvatica and Fraxinus spp.) and evergreen (Quercus ilex) species. Species-rich closed forest persisted until 6850 cal a BP, when Neolithic activities caused a forest decline and affected plant diversity. Secondary forest with abundant Ilex aquifoli…

1200-yr high-resolution terrestrial climate archive from the middle of the Mediterranean: The sedimentary record from Lake “Specchio di Venere” on Pa…

2011

The special location of Lake "Specchio di Venere" on Pantelleria Island in the Sicily Channel (Mediterranean Sea) between Tunisia and Sicily offers a unique terrestrial archive recording atmospheric changes, which are otherwise difficult to decipher in the marine records from this area. The lake is an endorheic saline basin with a maximum depth of 12.5 m. As the water input depends on rainfall, precipitation variations influence changes of the lake's water chemistry. In summer 2008, Lake Venere was cored with a modified Livingstone corer revealing a composite sedimentary sequence of 10.29 m length. Two radiocarbon dates form a preliminary age model indicating a very high sedimentation rate …

Primi dati sugli alberi monumentali di Pantelleria

2016

Poche o nulla sono le informazioni sugli alberi monumentali delle piccole isole che circondano la Sicilia. Ciò è dovuto innanzitutto alla rarità di alberi definibili monumentali, le piccole isole hanno subito infatti una trasformazione ancora più profonda della Sicilia, ma anche ad un difetto di conoscenza. Il nostro vuole essere un primo contributo alla conoscenza degli alberi monumentali nell’isola di Pantelleria. Gli alberi censiti appartengono a due specie, il pino marittimo (Pinus pinaster subsp. hamiltonii) e il leccio (Quercus ilex). In realtà nel caso del pino marittimo possiamo parlare di un “popolamento monumentale” corrispondente alla pineta a pino marittimo presso la località Mo…

Genetic diversity in Sicilian Population of Quercus ilex (Fagaceae)

2013

Carbon stock increases up to old growth forest along a secondary succession in Mediterranean island ecosystems.

2019

The occurrence of old-growth forests is quite limited in Mediterranean islands, which have been subject to particularly pronounced human impacts. Little is known about the carbon stocks of such peculiar ecosystems compared with different stages of secondary succession. We investigated the carbon variation in aboveground woody biomass, in litter and soil, and the nitrogen variation in litter and soil, in a 100 years long secondary succession in Mediterranean ecosystems. A vineyard, three stages of plant succession (high maquis, maquis-forest, and forest-maquis), and an old growth forest were compared. Soil samples at two soil depths (0-15 and 15-30 cm), and two litter types, relatively undec…

Brenneria quercina and Serratia spp. isolated from Spanish oak trees Molecular characterization and development of PCR primers

2008

Brenneria quercina has been reported as one of the causal agents of oak decline in Spain. To investigate the bacterial variability of this pathogen from different Spanish oak forests, a collection of 38 bacterial isolates from seven geographic locations and from different oak species was analysed by sequencing 16S rDNA and rep-PCR fingerprinting. All Spanish isolates of B. quercina were grouped by rep-PCR into a homogenous cluster that differed significantly from B. quercina reference strains from California. 16S rDNA analysis revealed that 34 out of 38 isolates were Brenneria. However, four isolates belonged to the genus Serratia, suggesting that this bacterium could cause cankers in oak t…

Aplicaciones de la embriogénesis somática para la propagación y mejora de Quercus ilex L. y Pinus spp.

2013

Esta tesis está enfocada a la aplicación de la embriogénesis somática para la conservación y mejora de Quercus ilex L., Pinus pinaster Aiton y Pinus pinea L., especies forestales representativas de los bosques de la Península Ibérica. La propagación clonal mediante embriogénesis somática (ES) es la herramienta más adecuada para la propagación de genotipos de élite y para la implementación de la llamada silvicultura multivarietal. Además los cultivos embriogénicos son explantos adecuados para iniciar experimentos de transformación genética con vistas a la introducción de características de interés o para estudios de genómica funcional. Quercus ilex (encina) es una de las especies más represe…

Vegetation dynamics on abandoned terraces of Sicily: the course and driving forces of succession

2007

In Mediterranean Europe, terrace landscapes can be found where 1) the orography is characterized by hills or mountains, 2) there is a high amount of stone outcrops and 3) the human need for agricultural production was quite high till the recent past. During the last century, many of these landscapes have been abandoned, due to their unsuitability for mechanized, intensive agriculture and due to the general land abandonment trend which arised in large parts of Europe. Since with land abandonment start secondary succession processes, the plant and animal communities linked to agroecosystems are replaced by other species which find their habitat in the developing succession stages. This proces…