1,720,981 research outputs found
Qualitative and quantitative aspects of olive production in relation to climate in southern Italy
No full textWe considered here olive production according to the main relationships between the quantitative (fruit production) and qualitative (oil quality) data and the meteorological parameters through the annual season. We carried out pollen monitoring analyses over a 12-year period, to initially define the main dynamics of pollen release into the atmosphere in a typical olive production area in southern Italy (Fasano, Puglia). Pollen release was generally determined by the meteorological factors in the period before flowering, with effects on both pollen amounts and timing of flowering (early or delayed). The interactions between these pollen and meteorological parameters were investigated using principal component analysis. This revealed clusters of independent variables during the biological cycle of the olive that highlighted the relationships between annual pollen production and future fruit production, with a high degree of interaction between environmental factors and final olive oil quality. This led us to search for statistical relationships between quality parameters of the oil (acidity, oxidative degree, fatty-acid composition) and meteorological parameters (mean monthly temperatures, rainfall, humidity, winds, solar radiation, evapotranspiration during post-flowering/pre-harvest). The water stress, as defined by the potential evapotranspiration, has a large influence on acidity and fatty-acid content of the olive oil produced. These data thus provide further support of the need for quality irrigation in olive production. (C) 2012 Elsevier B.V. All rights reserved
Control of biodeterioration using aerobiological monitoring: indoor investigations for the conservation of artistic patrimony.
No full textEffetto dei nuovi scenari climatici sulle aree coltivate a olivo nella Regione Puglia.
No full textOsservatorio agrometeorologico - Supplemento al settimanale Agricoltura Informazion
Pollen Morphology and Reproductive Performances in Opuntia ficus-indica (L.) Mill.
No full textThe fruits of Opuntia ficus-indica (L.) Mill., the most worldwide cultivated species of Cactaceae family, contain viable seeds (100-250) of large size. This characteristic influences the commercial quality of the fruit. The study of floral biology in Opuntia allows to understand the behaviour of the plant during reproductive phase and perhaps to distinguish clones with different fruits behaviour (with seed and seedless). The study resulted in a palynological characterization by optical and scanning microscopy (SEM), followed by a qualitative analysis on the male line with pollen viability and in vitro germination tests, in addition to a pollenpistil interaction survey. The plant material collected, during June-July 2010, consisted of clonal samples of the same genetic origin collected from populations characterizing the Sicilian cultivation area and distinguished in seedly cultivar ‘Gialla’ (yellow) and ‘Rossa’ (red) and seedless cultivar ‘Bianca’ (white). The palynological characterization revealed that Opuntia pollen has a radio-symmetric shape with a reticulated surface, poly-panto-porate with a perimeter from circular to polygonal. Moreover, the membrane of the pore appears finely granulated.
Scanning microscopy reveals that the pollen has an intectated, reticulated and hetero-brochated exine with about 20-24 pores with a thin membrane. The average viability of the pollen was 91.2% (± 4.6) in ‘Bianca’ cultivar, 82.40% (± 9.88) for both seedly cultivars. In vitro germination rate was 28.76% (± 6.59) in the white cultivar, 27.85% (± 5.15) as overall average in ‘Gialla’ and ‘Rossa’ cultivar. In vivo germination rate in the seedless cultivar (75.77% ± 5.32) was higher than what was that recorded in the other two (53.5% ± 6.5)
Meteorological Influences on Pheno–Morpho–Yield Data of Grain Sorghum Varieties in Central Italy
No full textSorghum (Sorghum bicolor L. Moench) is widely grown in many arid and semiarid areas of the world due to its ability to yield well under rainfed or water-limited conditions. In the present study some sorghum varieties (medium-long season) have been studied in relationship with the principal meteorological variables considering also the drought effect in a favorable groundwater situation. The phenological adaptation, morphological and productive features during 11 yr of investigations from 2005 to 2015 in central Italy were evaluated. In the study area the soil water availability from emergence to flowering was high for all the varieties development considering that no significant phenological differences were evidenced also after flowering between the groups of sorghum cultivars. The plant vegetative development and in particular the flag leaf height was influenced by the low precipitation volumes recorded during 2007 and 2015 spring periods such as plant height particularly affected by extremely low rain volumes from May to July during the last study year. Moreover, seed numbers may be reduced if drought stress occurs immediately after seed set as a result of embryo abortion and the quite absent precipitations during summer 2007 (above all during August when average sorghum flowering is recorded) resulted in a reduction of kernel weight for almost all the varieties. The highest groundwater depth (conditioned by low precipitation volumes) recorded during 2015 determined a high water stress that may have influenced above all panicle size and consequently the number of seeds per panicle
Il ruolo delle temperature primaverili sull'evento fioritura in olivo ed elaborazione delle soglie di "risveglio" degli apparati riproduttivi.
No full textClimate change impact on the olive pollen season in Mediterranean areas of Italy: air quality in late spring from an allergenic point of view
No full textRecent studies have shown that there are many effects of climate change on aeroallergens, and thus on allergic diseases in humans. In the Mediterranean region, despite the importance of the olive tree for production, there is high allergenicity of olive pollen and related risks to human health. Aerobiological sampling techniques can be used to analyse the pollinosis phenomenon through determination of mean daily pollen concentrations per cubic metre of air. The present study was carried out from 1999 to 2008 in 16 olive-growing areas in Italy, to update the information on the pollinosis characteristics of Olea europaea in the study areas. The analysis of the average flowering season over the study period highlights a temporal scaling of pollen in the atmosphere that depends on the different climatic characteristics. This is mainly dependent on temperature, and in part, determined by latitude. Generally, the levels of O. europaea pollen in the atmosphere are higher from mid-April to the end of June, with the period of greatest risk to human health due to this olive pollen in this area currently limited primarily to the last 10 days of May. However, the pollen season can move, depending on the climate scenario considered, and data here can be used to determine potential time shifts in pollinosis that might cause more precocious asthma and allergy problems. The allergy season for this type of pollen might be significantly precocious in future decades (20-30 days earlier in the year), which will impact on the severity and duration of allergies attributable to olive tree pollen
POTENTIAL SHIFTS IN OLIVE FLOWERING ACCORDING TO CLIMATE VARIATIONS IN SOUTHERN ITALY
No full textPhenological investigations that adopt aerobiological monitoring methodologies are frequently used for species that rely on the wind for pollen grain dispersion, such as the olive in the Mediterranean basin. The present study of olive flowering dates was carried out in the Calabria region (southern Italy). These were calculated on the basis of a phenological study of pollen levels in the atmosphere in three typical olive-growing areas over an 11 year study period (1999–2009). This phenological method provides olive flowering maps that are based on temperatures (as the growing degree days: GDDs), which are highly correlated with the release of the pollen grains. According to the model developed, the average GDDs corresponding to the flowering dates were calculated for the baseline period of 1981–2000. Moreover, with the use of meteorological data derived from the Intergovernmental Panel on Climate Change scenarios, the future olive flowering dates are estimated for the 20 year period from 2081 to 2100. The close relationships between the spring temperature trends and the reproductive phenological phases in the olive are highly sensitive to climatic change, which has implications in terms of potential latitude and altitude shifts in the olive cultivation areas. In some cultivation areas in southern Italy, the present particular combination of microclimate, soil status and level of erosion is considered as limiting to regular vegetative plant development. However, the use of olive cultivars that are specifically adapted to extremely stressful environments, in terms of high temperatures and water deficit, might represent the main solution for the mitigation of the consequences of climatic change. Copyright © 2012 Royal Meteorological Society
Bioclimatic characterisation of the Mediterranean region: future climate projections for Spain, Italy and Tunisia
No full textThe present study provides a meteorological and bioclimatic characterisation of three Mediterranean areas:
Spain, Italy and Tunisia. This includes, on the one hand, an evaluation of the past climate using meteorological data
collected from 1931 to 1994. On the other hand, the future climate characterisation has been constructed for each
study area, under the projected A1B emission scenario for the 2081 to 2100 period. Three Bioclimatic Indices are used
to compare the annual and seasonal climate from these past periods through to these future periods: the Ombrothermic
Index, the Continentality Index and the Thermicity Index. A clear tendency toward semicontinentality in the
Mediterranean basin is observed, and higher thermicity is expected in the future. The Ombroclimatic Index, and
especially the seasonal indices, is the most helpful of these Bioclimatic Indices, showing that the southern Mediterranean
areas would be the most vulnerable to climate change
- …
