Evaluation of conservation tillage and rotation with legumes as adaptation and mitigation strategies of climate change on durum wheat in Sardinia

This study aimed to evaluate the interaction between conservation tillage and rotation with legumes on durum wheat phenology and production, in climate change conditions. The CSM-CERES-Wheat model (DSSAT beta 4.5), in combination with a stochastic Weather Generator (WG), were used to assess climate change impacts and suggest adaptation strategies to cope with climate change. Twenty-seven climate change scenarios (GCMs-based), obtained with the pattern scaling technique considering three values of climate sensitivity and four emission scenarios, for the periods 2025, 2050 and 2075, were used. The direct and indirect effects of projected changes in atmospheric CO2 concentrations, on the alternative cropping systems, were evaluated. The results on yield, for present climate conditions, showed a substantial indifference between tillage practices, whereas the crop rotation with legumes favoured quantity and quality of grain yield. This behaviour has been observed also in simulations carried out using future climate change scenarios, that, however, showed a high variability depending on the wide range of climate scenarios used mainly in the more distant future periods. The uncertainties linked to climate sensitivity, emission scenarios and atmospheric CO2 concentrations are among the main causes of this wide variability. The application of conservation tillage might be recommended in this region because permits a more environmentally and economically sustainable management

Attività di R&S nell'ambito del settore agricolo

2008-11-25Aula Magna Facoltà di Ingegneria, CagliariLo stato dell’arte della ricerca scientifica nel settore della produzione di energia da biomass

A Chemometric Approach to Assess the Rheological Properties of Durum Wheat Dough by Indirect FTIR Measurements

Rheological measurements and FTIR spectroscopy were used to characterize different doughs, obtained by commercial and monovarietal durum wheat flours (Cappelli and Karalis). Rheological frequency sweep tests were carried out, and the Weak Gel model, whose parameters may be related to gluten network extension and strength, was applied. IR analysis mainly focused on the Amide III band, revealing significant variations in the gluten network. Compared to the other varieties, Karalis semolina showed a higher amount of α-helices and a lower amount of β-sheets and random structures. Spectroscopic and rheological data were then correlated using Partial Least Squares regression (PLS) coupled with the Variable Importance in Projection (VIP) technique. The combined use of the techniques provided useful insights into the interplay among protein structures, gluten network features, and rheological properties. In detail, β-sheets and α-helices protein conformations were shown to significantly affect the gluten network\u27s mechanical strength

Effect of pregnancy and birth on the course of myasthenia gravis before or after transsternal radical thymectomy

Objective: Myasthenia gravis (MG) affects women at childbearing age. Therefore, the question arises if these patients should become pregnant and if thymectomy has a positive effect on the course of MG in pregnant patients. Methods: Fifteen pregnancies had been followed retrospectively. All patients underwent transsternal radical thymectomy for MG. The course of MG in the period before, during, and after the pregnancy was scored according to Ossermann's classification. The effect of thymectomy on delivery and on the newborns was evaluated. Results: Patients were divided in two groups: pregnancies before (group I, n = 8) and after (group II, n = 7) thymectomy. During pregnancy, in group I, one deterioration was observed and in seven patients the disease was unchanged. In group II, one deterioration, five unchanged courses, and one improvement were observed. In the postpartum period, in group I, seven patients did not change and one improved. In group II, two deteriorations, three unchanged courses, and two improvements were observed. Before pregnancy, group II patients were in a better Ossermann stage in comparison with those in group I. Eight of the 12 deliveries were spontaneous (three abortus). Myasthenic symptoms were observed in two newborns in group I. Conclusion: Our data suggest that MG is not prohibitive to have children. The course of MG after transsternal radical thymectomy is often ameliorated. A better MG-stage, reached after thymectomy, before pregnancy seems to be correlated with a better course during pregnanc

Broadband Dielectric Spectroscopy (BDS) investigation of molecular relaxations in durum wheat dough at low temperatures and their relationship with rheological properties

Broadband Dielectric Spectroscopy (BDS) was used to study the dielectric relaxation processes of semolina doughs. The dielectric properties were analyzed as a function of water content, and, additionally, the effects of NaCl presence and semolina characteristics were investigated. The dough was prepared using three different varieties of semolina. BDS measurements were conducted using a custom-made Rheo-dielectric tool composed of a Broadband Dielectric/Impedance Spectrometer connected to a strain-controlled rheometer. The temperature range investigated was from −135 °C to 25 °C, with a step of 5 °C, while the frequency range was 10$_{−1}$ – 10$_7$ Hz. Dielectric spectroscopy turned out to be a valuable technique for dough characterization. It is capable to distinguish the carbohydrates contribution and the different interactions between water and dough components. Moreover, this unique combination allows assessing correlations between rheological and dielectric properties, like the compliance of dough as a function of the relaxation processes and the influence of semolina components

Characterisation of the intracellular protozoan MPX in Scottish mussels, Mytilus edulis Linnaeus, 1758

Ciliates have been reported as pathogens of many species of economically important bivalves. Mussel protozoan X (MPX), is an uncharacterised intracellular ciliate of mussels and has been widely reported in Mytilus spp. around the world. In order to characterise this ciliate, Mytilus edulis samples were collected from a site on the West coast of Scotland, and four different fixatives for histological examination were tested. Fresh preparations of mussel digestive glands were also examined by laser scanning confocal microscopy. Intracellular ciliates were prepared by laser capture microdissection and partial sequences of small subunit ribosomal RNA gene and of large subunit ribosomal RNA gene were generated, using Phyllopharyngea primers. Methacarn solution proved to be the best fixative for both histological and molecular characterisation. The morphological and molecular investigations confirmed that this ciliate belongs to the class Phyllopharyngea, order Rhynchodida. However, this organism does not belong to any known family, genus or species, therefore, a new description is necessary, following further morphological analyses. Most mussel samples containing MPX displayed mild to moderate infections, with no signs of necrosis or haemocytic response, although a single sample displayed a severe infection (∼103 ciliates per section). The localisation of this ciliate in tissues other than the digestive gland, the presence of necrosis in infected tissue of the most severely infected mussel and the binary fission of this ciliate have been observed here for the first time. We also report the first observation of the live ciliate isolated from tissue. Although MPX remains of unknown significance to the mussel industry, tools and protocols described here will be useful in further characterising these and other ciliates (subclass Rhynchodia) known as pathogens for bivalves

Characterisation of the intracellular protozoan MPX in Scottish mussels, Mytilus edulis Linnaeus, 1758

Ciliates have been reported as pathogens of many species of economically important bivalves. Mussel protozoan X (MPX), is an uncharacterised intracellular ciliate of mussels and has been widely reported in Mytilus spp. around the world. In order to characterise this ciliate, Mytilus edulis samples were collected from a site on the West coast of Scotland, and four different fixatives for histological examination were tested. Fresh preparations of mussel digestive glands were also examined by laser scanning confocal microscopy. Intracellular ciliates were prepared by laser capture microdissection and partial sequences of small subunit ribosomal RNA gene and of large subunit ribosomal RNA gene were generated, using Phyllopharyngea primers. Methacarn solution proved to be the best fixative for both histological and molecular characterisation. The morphological and molecular investigations confirmed that this ciliate belongs to the class Phyllopharyngea, order Rhynchodida. However, this organism does not belong to any known family, genus or species, therefore, a new description is necessary, following further morphological analyses. Most mussel samples containing MPX displayed mild to moderate infections, with no signs of necrosis or haemocytic response, although a single sample displayed a severe infection (∼103 ciliates per section). The localisation of this ciliate in tissues other than the digestive gland, the presence of necrosis in infected tissue of the most severely infected mussel and the binary fission of this ciliate have been observed here for the first time. We also report the first observation of the live ciliate isolated from tissue. Although MPX remains of unknown significance to the mussel industry, tools and protocols described here will be useful in further characterising these and other ciliates (subclass Rhynchodia) known as pathogens for bivalves.REF Compliant by Deposit in Stirling's Repositor

LCA study of oleaginous bioenergy chains in a Mediterranean environment

This paper reports outcomes of life cycle assessments (LCAs) of three different oleaginous bioenergy chains (oilseed rape, Ethiopian mustard and cardoon) under Southern Europe conditions. Accurate data on field practices previously collected during a three-year study at two sites were used. The vegetable oil produced by oleaginous seeds was used for power generation in medium-speed diesel engines while the crop residues were used in steam power plants. For each bioenergy chain, the environmental impact related to cultivation, transportation of agricultural products and industrial conversion for power generation was evaluated by calculating cumulative energy demand, acidification potential and global warming potential. For all three bioenergy chains, the results of the LCA study show a considerable saving of primary energy (from 70 to 86 GJ·ha−1) and greenhouse gas emissions (from 4.1 to 5.2 t CO2·ha−1) in comparison to power generation from fossil fuels, although the acidification potential of these bioenergy chains may be twice that of conventional power generation. In addition, the study highlights that land use changes due to the cultivation of the abovementioned crops reduce soil organic content and therefore worsen and increase greenhouse gas emissions for all three bioenergy chains. The study also demonstrates that the exploitation of crop residues for energy production greatly contributes to managing environmental impact of the three bioenergy chains

Resistencia al aplastamiento en madera de álamo para uniones mecánicas de diámetro 5 mm

El eeglamento argentino de estructuras de madera CIRSOC 601 propone valores de resistencia al aplastamiento en función de la gravedad anhidra y el diámetro del perno. Estos valores tienen su origen en la norma americana NDS 2005. El Suplemento 4 del citado reglamento considera que la resistencia al aplastamiento para diámetros menores a 6,35 mm es independiente de la dirección de las fibras y del diámetro del perno. Para diámetros mayores a 6,35 mm, relaciona la resistencia al aplastamiento perpendicular a la fibra con el diámetro de la clavija y considera que la resistencia al aplastamiento en la dirección paralela a la fibra es independiente de dicho parámetro. Resulta necesario verificar estos valores para maderas argentinas, en particular para las provenientes de bosques implantados. En este trabajo se determinaron los valores de resistencia al aplastamiento para madera de Álamo, Populus deltoides clones ‘Australiano 129/60’ y “Stoneville 67" procedente de bosques implantados en la localidad de Morse, al Noroeste de la Provincia de Buenos Aires, Argentina, y se analizó la correlación entre la resistencia al aplastamiento y la densidad anhidra. Se efectuaron 98 ensayos de acuerdo a las prescripciones de la norma UNE-EN 383:2007, 64 en la dirección paralela a las fibras y 34 en dirección perpendicular, se utilizaron pernos rígidos de 5 mm. Los resultados obtenidos muestran que la resistencia en la dirección paralela es ligeramente superior (7 %) a la obtenida para la dirección perpendicular, 24,8 N/mm2 versus 23,0 N/mm2. Los valores experimentales son inferiores a los propuestos por el CIRSOC 601, en un 5 % para la dirección paralela y en un 17 % para la dirección perpendicularFil: Zorrilla, Lautaro. Argentina. Universidad Nacional del Noroeste.Fil: Lombardo, Gianluca. Argentina. Universidad Nacional del Noroeste.Fil: Carboni, Francisco. Argentina. Universidad Nacional del Noroeste.Fil: Cichero, Renso. Argentina. Universidad Nacional del Noroeste

Modeling high-resolution climate change impacts on wheat and maize in Italy

Abstract The Mediterranean basin has been identified as a prominent hotspot of climate change, with expected negative impacts on crop productivity, among others. Given the primary role that agriculture has to sustain cultural values, economic opportunities, and food security, it is crucial to identify specific risks in agriculture due to climate change, which can address more effective adaptation strategies and policies to cope with climate change. This study aims to evaluate the high-resolution impacts of climate change on the length of the growing cycle and yield of durum wheat, common wheat, and maize in Italy by using the CERES-Wheat and CERES-Maize crop models implemented in the Decision Support System for Agrotechnology Transfer (DSSAT) software. A digital platform (GIS-DSSAT) was developed to couple crop simulation models with dynamically downscaled climate projections at high resolution for Italy, which can better represent the Italian landscape complexity and the spatial distribution of different pedological and crop management features, providing more detailed information on the expected impacts on crops respect to previous studies at a coarser resolution. The projections have been extended for two climate change scenarios and accounting for uncertainty, either considering or not the potential direct effects of increasing atmospheric CO2 concentrations ([CO2]). Results show that climate change may affect Italian cereal production in the medium to long term periods. Maize is the main affected crop, with yield reductions homogeneously distributed from North to South Italy. Wheat yield is expected to decrease mainly in southern Italy, while northern Italy may benefit from higher precipitation regimes. Higher levels of atmospheric CO2 concentrations may partially offset the negative impact posed by climate change and increase the benefits in the northern regions, especially for common and durum wheat