Possibilità produttive di alcune varietà di soia: risultati di un triennio di esperienze condotte in Sardegna

During 1975-76-77, 25 soybeans varieties belonging to different groups of maturity were compared. Experiments - carried out in two different pedoclimatic environments - pointed out the importance of the choice of variety both for production purposes and with reference to harvest time. In the trial carried in the Northern Sardinia, on a calcareous soil, the following varieties showed to be the most productive: «Hodyson» (46.2 q/ha), «Amsoy 71» (45.2 q/ha), «Wells» (43.2 q/ha), « Beeson» (42.9 q/ha), «Corsoy» (42.1 q/ha) and «Williams» (41.5 q/ha). On the contrary, on clayish soils the above varieties were slightly productive, while other ones («Semmes», «Rillito», «Davis»), which gave yields of about 30 q/ha, resulted to be too late. Further trials are required to detect cultivars which, both for the bioiogica1 cycle span and for the yields may be successfully cultivated in southern pedoclimatic environments similar to those where experiments were carried out. Nel corso degli anni 1975-76-77 sono state confrontate 25 varietà di soia appartenenti a differenti classi di maturazione. Le esperienze, condotte in due differenti ambienti pedoclimatici, hanno evidenziato l'importanza della scelta varietale sia ai fini produttivi che con riferimento all'epoca di raccolta. Nella prova condotta nella Sardegna settentrionale, su terreno di origine calcareo, sono risultate più produttive le varietà «Hodgson» (46,2 q/ha), «Amsoy 71» (45,2 q/ha), «Wells» (43,2 q/ha), «Beeson» (42,9 q/ha), «Corsoy» (42,1 q/ha) e «Williams» (41,5 q/ha). Su terreni argillosi dell'Oristanese, invece, le stesse varietà hanno mostrato scarse attitudini produttive, mentre altre («Semmes», «Rillito», «Davis»), che hanno fornito rese intorno a 30 q/ha, sono risultate troppo tardive. Si ritengono pertanto necessarie ulteriori prove agronomiche tendenti all'individuazione di cultivar che, sia per lunghezza del ciclo biologico che per le rese unitarie, possano essere inserite con successo in ambienti pedoclimatici meridionali del tipo di quelli sede delle prove

Reconstructing eruptive source parameters from tephra deposit: a numerical study of medium-sized explosive eruptions at Etna volcano

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Phytotoxic metabolites produced by fungi involvedin cork oak decline

Diplodia corticola, anamorph of Botryosphaeria corticola Phillips, Alves et Luque, and Biscognauxia mediterranea (De Not.) O. Kuntze (= Hypoxylon mediterraneum) have often been associated with serious decline phenomena, which have been affecting the cork oak forest in Italy and other Mediterranean countries for several years. Diplodia corticola is widespread in Sardinian oak forests, and can affect plants of different ages, inducing symptoms which include dieback, cankers and vascular necrosis. These studies may provide information which could be useful for understanding the chemistry and the biology governing the relationship between these fungi and their hosts. Further studies should aim to also evaluate the ecological role of these substances

Diplofuranones A and B, two further new 4-monosubstituted 2(3<i>H</i>)-dihydrofuranones produced by <i>Diplodia corticola</i>, a fungus pathogen of cork oak

Two new 4-monosubstituted 2(3H)-dihydrofuranones, named diplofuranones A and B, were isolated from liquid cultures of Diplodia corticola, a plant pathogenic fungus causing a canker disease of cork oak (Quercus suber L.). The same fungus also produces several metabolites such as the diplopyrone, the (3S,4R)-trans- and the (3R,4R)-cis-4-hydroxymellein, the sapinofuranone B and its (S,S)-enantiomer, the well known sphaeropsidins A-C, and the diplobifuranylones A and B. The diplofuranones A and B were characterised, using spectroscopic (essentially NMR and MS techniques) methods, as the 4-[(1E,3E)-5-hydroxyhexadienyl]butan-4-olide and its corresponding 3,4-dihydro side chain derivative. The stereochemistry of the stereogenic secondary hydroxylated carbon of the side chain of diplofuranone A was determined by application of Mosher’s method and proved to be R. Diplofuranone A tested at 0.2 mg mL-1 on non-host plant did not show phytotoxic activity

Possibilità produttive di erbai e cereali autunno-vernini in ambienti marginali dell'alta collina sarda

Over the 3 years from 1975 to 1979, yielding capacity of some annual forage crops and winter cereals was tested on marginal lands of the Sardinian hills. Triticale achieved the best results among these cereals both in direct winter use and doughy stage maturation harvesting. The vetch and oats association ensures the best spring production. An association of ray grass andcrimson clover seems interesting because of these plants facility in self seeding

Possibilità produttive dei prati monofiti di graminacee in ambiente mediterraneo

Over the four years from 1973 to 1977 the productive capacity of 20 grasses was tested on calcareous soils of northern Sardinia. The tall fescue «Maris Djebel» and «Manade» were the most productive achiving 46 and 44 t/ha of DM over the quadriennium, about half of which in autunn-winter period. The cocks-foot «Floreal» achieved good results especially with regard to the best hay production. The perennial ryegrass and Toowoomba canarygrass which had been decimated at the beginning of the third year showed poor adaptability. The Swiss ryegrass « Manava» gave good results in the first biennium (24 t/ha of DM) but later the yield was reduced because of difficulty in self-seeding

Electric-field-dependent empirical potentials for molecules and crystals: a first application to flexible water molecule adsorbed in zeolites

A general method to include electric-field-dependent terms in empirical potential functions representing interatomic interactions is proposed. It is applied to derive an intramolecular potential model for the water molecule able to reproduce the effects of an electric field on its geometry and dynamics: to enlarge the HOH angle, to increase slightly the OH bond lengths, to red-shift the stretching vibrational frequencies, and to blue-shift slightly the bending mode frequency. These effects have been detected experimentally for water adsorbed in zeolites and have been confirmed by quantum mechanical calculations. The electric-field-dependent intramolecular potential model for water has been combined with a newly refined intermolecular potential for bulk water and with new potentials representing cation–water and aluminosilicate–water interactions in order to simulate, by classical molecular dynamics (MD) technique, the behavior of water adsorbed in zeolites. The performances of the model have been checked by a MD simulation of liquid water at room temperature, by the structural and vibrational properties of the water dimer, and by test MD calculations on a hydrated natural zeolite (natrolite). The results are encouraging, and the simulations will be extended to study the behavior of water adsorbed in other zeolites, including diffusion and some aspects of ion exchange processes

Grain size distribution uncertainty quantification in volcanic ash dispersal and deposition from weak plumes

We present the results of uncertainty quantification and sensitivity analysis applied to volcanic ash dispersal from weak plumes with focus on the uncertainties associated to the original grain size distribution of the mixture. The Lagrangian particle model Lagrangian Particles Advection Code is used to simulate the transport of inertial particles under the action of realistic atmospheric conditions. The particle motion equations are derived by expressing the particle acceleration as the sum of forces acting along its trajectory, with the drag force calculated as a function of particle diameter, density, shape, and Reynolds number. Simulations are representative of a weak plume event of Mount Etna (Italy) and aimed at quantifying the effect on the dispersal process of the uncertainty in the mean and standard deviation of a lognormal function describing the initial grain size distribution and in particle sphericity. In order to analyze the sensitivity of particle dispersal to these uncertain variables with a reasonable number of simulations, response surfaces in the parameter space are built by using the generalized polynomial chaos expansion technique. The mean diameter and standard deviation of particle size distribution, and their probability density functions, at various distances from the source, both airborne and on ground, are quantified. Results highlight that uncertainty ranges in these quantities are drastically reduced with distance from source, making them largely dependent just on the location. Moreover, at a given distance from source, the distribution is mostly controlled by particle sphericity, particularly on the ground, whereas in air also mean diameter and sorting play a main role

Water use and crop coefficients in sprinkler irrigated rice

Field experiments were carried out during the years 2002, 2004, 2005 and 2006 to analyze water-soil-atmosphere interactions in sprinkler irrigated rice. The research was carried out in Sardinia (39° 59' N; 8° 40' E, at altitude 15 m). The cultivars used in the experiments, respectively in 2002 and in 2004-2005-2006, were Irat 212 and Eurosis. In each year cultivars were subjected to the same crop management. Irrigation was applied since the emergence with the sprinkler method, taking into account the loss of water from 'Class A' pan evaporation. Soil water content was monitored at 0.10 m intervals until l.00-m depth using a 'Diviner 2000' (Sentek). In 2002 seven irrigation scheduling treatments were compared. In 2004, 2005, 2006 irrigation treatments provided for optimal soil water conditions during the growing season. In 2002 the results highlighted: 1) 0-0.20 m depth was the most important layer for crop water uptake and the best correlated layer with rice rough yield; 2) the positive relationship between yield and water supply was significant until 6500 m3 ha-1 of water applied. Further seasonal irrigation volumes did not increase significantly yield. In 2004, 2005 and 2006 the analysis of the soil water balance at different crop phenological stages allowed to estimate crop coefficients (Kc) using the Penman-Monteith equation and the 'Class A' pan evaporation (Kcev). Kc varied over the three-year period on average from 0.90 to l.07 and 0.97, respectively for the emergence-end of tillering, end of tillering-heading and heading-maturing periods, while crop coefficients as a ratio between maximum crop evapotranspiration (ETc) and Epan, Kcev ranged from 0.78 to 0.92 and 0.81 for the same time perio

The epiphytic transcriptome of Podosphaera fusca and its predicted secretome

Comunicación presentada en formato panel en la sesión "Large-scale (omics) approaches"The cucurbit powdery mildew fungus Podosphaera fusca, is a major limiting factor for cucurbit production worldwide. Despite its agronomic and economic importance, very little is known about fundamental aspects of P. fusca biology such as obligate biotrophy and pathogenesis. In order to design novel and more durable control strategies, genomic information of P. fusca is needed. In this work we aimed to analyse the epiphytic transcriptome of P. fusca as starting point. Total RNA was isolated from mycelia and conidia, and the corresponding cDNA library was sequenced using a 454 GS FLX platform. Annotation data was acquired for 62.6% of the assembled sequences, identifying 9,713 putative genes with different orthologues. In the transcript data set, the most represented protein functions were those involved in gene expression, protein metabolism, regulation of biological process and organelle organization. Our analysis also confirmed the existence of “missing ascomycete core genes” (MACGs) found in other powdery mildew species. After analysis of the pool of fungal secreted proteins, 118 putative secreted proteins were identified, including 35 “candidate secreted effector proteins” (CSEPs) specific for P. fusca. In order to validate the in silico assembly, the expression profile of some CSEPs was analysed, which was consequent with a canonical effector expression pattern, with a maximum of expression at the beginning of the infection process 24-48 h after inoculation. Our data open the genomics era of this very important cucurbit pathogen.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Plan Nacional Plan I+D+I del antiguo Ministerio de Ciencia e Innovación (AGL2010-21848-CO2-01), cofinanciado con fondos FEDER (UE)