1,720,973 research outputs found
Valorizzazione di germoplasma di Pistacia lentiscus L. ed utilizzo di marcatori molecolari a fini vivaistici
No full textProanthocyanidins from Hedysarum, Lotus and Onobrychis spp. growing in Sardinia and Sicily and their antioxidant activity.
No full textInoculation and fertilization affect sulla performance in a new cultivation area
No full textThe forage legume sulla (Sulla coronaria (L.) Medik) establishes a host-speciic nitrogen-ixing symbiotic
interaction and its inoculation is mandatory where it is cultivated for the irst time or not present as
spontaneous species. his study aimed at investigating the efects of inoculation and fertilizer nitrogen (N)
on yield performance and N-ixation ability of sulla established in a new habitat within a Mediterranean
agropastoral area of Sardinia (Italy). Sulla plants, previously inoculated with peat-based inoculant, liquid
inoculant and soil, and unfertilized (N0) or N100 fertilized, were sampled at full vegetative stage. Length,
dry matter yield and ixed N of sulla shoots and roots were measured. Inoculation signiicantly afected
several traits. In particular, plant DM varied from 0.5 to 3.2 g in uninoculated and inoculated plants,
respectively. At N0 and using soil as inoculant, shoot ixed N reached 43 mg plant-1 whereas it was
negligible in the uninoculated control. Under N100, N-ixation ability of sulla was decreased. Results
highlighted that inoculation is essential for extending the cultivation of sulla in a new habitat
RACCOLTA DI RESINE IN COLONIE DI APIS MELLIFERA LIGUSTICA INFESTATE DA VARROA DESTRUCTOR
No full textCharacterization of Sardinian cork oak (Quercus suber L.) genetic resources for economically important traits
No full text"Considering the very high socio economic value of cork oak (Quercus suber L.) in Mediterranean areas, a better knowledge of local genetic resources is necessary in order to reach a good balance between the conservation issues and the need of an efficient cork production network. In such frame, local germplasm of Q. suber from the main cork production areas of Sardinia was analysed for DNA and isozyme polymorphisms and for cork quality in relation to some environmental parameters. A total number of 24 sample stands of cork oak were selected, representing typical vegetation, sylvicultural and cork quality features within the eight identified cork growing areas in Sardinia. Considerable variation was found between cork oak stands of the different areas. Results of the principal component analysis performed on the cork quality data and environmental characters of the eight areas, showed that the first three components explain 72. 2% of the variation. The major characters involved in this differentiation were cork quality characters such as dimensional recover, moisture and Mg content of the cork and also elevation of stands m a. s. l. for the first component. The second component appears to be determined by some climatic parameters (average annual temperature and average of the minimum temperatures of coldest month) and by the Fe and Zn in the cork. For the third component, major characters involved in differentiation are average annual rainfall, bark thickness and Ca content in the cork.
Combined effects of microenvironment and land use on C fluxes in a Mediterranean agro-silvopastoral system
No full textAppropriate agroforestry practices might contribute to carbon sequestration and cope with climate change by modulating ecosystem services. It is known that land use change might affect soil-atmosphere carbon dioxide (CO2) effluxes of agro-silvopastoral systems. However, little information is available at single microenvironment level. Across four years, fortnightly measurements of soil respiration were carried out at different microenvironment (beneath tree cover vs open areas) and land use (native understorey vs its conversion into improved pasture) within a high-density evergreen cork oak forest of Sardinia (Italy). We also monitored aboveground dry matter yields and soil carbon stocks. Measurements revealed that the two investigated microenvironments widely differed for the amounts of photosynthetically active radiation and microclimatic traits such as soil water content, air humidity, soil and air temperature. High seasonal and inter-annual variability in soil respiration rates was recorded (range 0.3–12.6 CO2 μmol m−2 s-1) and the peak values were reached in the summer of the third year in the improved pasture beneath tree cover. The conversion of the native understorey into improved pasture beneath cork oak increased significantly the annual cumulative soil respiration for three consecutive years, reaching values of about 71, 36 and 100 t CO2 ha−1 yr−1, which were from 38 to 88 % higher than the remaining treatments. On average, heterotrophic component represented from 68–76% of soil respiration. An extreme drought event, which was emblematic of a climate change context, was experienced in the second year. It countered the increase in the heterotrophic component of soil respiration and minimized up to 20-fold the forage on offer from pasture swards. Based on measured CO2 effluxes, the study demonstrated that the effects of the land use change at the microenvironment beneath tree cover were substantially unbalanced in terms of soil organic carbon stocks. Therefore, results suggest avoiding the soil mechanical disturbance beneath cork oak in the investigated ecosystem to reduce anthropogenic carbon fluxes to the atmosphere
- …
