55 research outputs found

    Response of Contrasting Cocksfoot Varieties to Summer Moisture Availability in a Mediterranean Environment

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    The responsiveness to water availability in summer and the effect of summer drought were assessed in a Mediterranean environment on both temperate and Mediterranean cocksfoot (Dactylis glomerata L.) materials. Three consecutive evaluation phases were contemplated: i) under rainfed conditions from autumn to spring; ii) under contrasting moisture conditions in the following summer; and iii) under rainfed conditions in the subsequent autumn-spring season to assess the effect of the previous summer treatments. The ability to become summer dormant under conducive conditions, such as in Mediterranean germplasm, proved a plant pre-requisite for survival under drought. All the “summer-active”, temperate varieties did not survive drought stress. Mediterranean materials showed a facultative dormancy behaviour in that they responded to moisture availability in summer. There was evidence that selection for such responsiveness was effective, as shown by a variety selected from Mediterranean germplasm also considering this criterion. Forcing summer growth by preventing dormancy had little detrimental effect on subsequent autumn recovery of Mediterranean improved varieties but more evidence is required on this aspect

    Effectiveness of the GAEC cross compliance standard Protection of permanent pasture: prohibition to convert permanent pasture into arable crops in avoiding habitat deterioration

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    By the end of the 19th and beginning of the 20th century new developments in agricultural technology caused an intensification of the agricultural practices. Species adapted to the diversity of structures or resources of high naturalistic value farmlands, like permanent pasture, cannot survive under increasingly high intensity agricultural management. The Italian MD n.30125 dated 22/12/2009 (Standard 4.1) defines, among the measures for the protection of permanent pasture and avoidance the deterioration of habitats, the prohibition to convert permanent pasture into arable crops and to till with the exception of agricultural practices related to the renewal and/or thickening of the sward and to the drainage water management. Permanent pastures biodiversity performs key ecological services and if correctly assembled in time and space can lead to agroecosystems capable of sponsoring their own soil fertility, crop protection and productivity. The vegetative cover of permanent pasture prevents soil erosion, replenishes ground water and controls flooding by enhancing infiltration and reducing runoff. The changes of land use or some practices change insect community and vegetation diversity. Physical disturbance of the soil caused by tillage increases risk of erosion and reduces the recycling of nutrients and proper balance between organic matter, soil organism and plant diversity. Is necessary a habitat preservation policy because after a change, even a return to past management would not completely re-establish the complex structure of habitats

    A simple pressure assisted method for MicroED specimen preparation

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    Micro-crystal electron diffraction (MicroED) has shown great potential for structure determination of macromolecular crystals too small for X-ray diffraction. However, specimen preparation remains a major bottleneck. Here, we report a simple method for preparing MicroED specimens, named Preassis, in which excess liquid is removed through an EM grid with the assistance of pressure. We show the ice thicknesses can be controlled by tuning the pressure in combination with EM grids with appropriate carbon hole sizes. Importantly, Preassis can handle a wide range of protein crystals grown in various buffer conditions including those with high viscosity, as well as samples with low crystal concentrations. Preassis is a simple and universal method for MicroED specimen preparation, and will significantly broaden the applications of MicroED

    Coupling Lipid Nanoparticle Structure and Automated Single Particle Composition Analysis to Design Phospholipase Responsive Nanocarriers

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    Lipid nanoparticles (LNPs) are versatile structures with tunable physicochemical properties that are ideally suited as a platform for vaccine delivery and RNA therapeutics. A key barrier to LNP rational design is the inability to relate composition and structure to intracellular processing and function. Here we combine Single Particle Automated Raman Trapping Analysis (SPARTA®) with small angle scattering (SAXS / SANS) techniques to link LNP composition with internal structure and morphology and to monitor dynamic LNP - phospholipase D (PLD) interactions. Our analysis demonstrates that phospholipase D, a key intracellular trafficking mediator, can access the entire LNP lipid membrane to generate stable, anionic LNPs. PLD activity on vesicles with matched amounts of enzyme substrate was an order of magnitude lower, indicating that the LNP lipid membrane structure can be used to control enzyme interactions. This represents an opportunity to design enzyme-responsive LNP solutions for stimuli-responsive delivery and diseases where PLD is dysregulated

    Drought and high temperature resistance evaluation of Dactylis glomerata L

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    With the aim to identify cultivars characterized by high drought and temperature resistance and high water use efficiency a study was carried out on 1 accession (Jana) and 4 Sardinian ecotypes of orchard grass (Dactylis glomerata L.) (Bolotana, Bonorva, Bonnanaro, Platamona). To evaluate the adaptive responses of different D. glomerata ecotypes, two trials were carried out in order to evaluate drought resistance under rain proof shelter and controlled water supply, and to evaluate high temperature resistance in a greenhouse where high summer temperature (daily maximum temperature > 50 °C) were monitored. On December 2010 seeds were sown in seed benches at the beginning of March the plants were transplanted at the 5th leaf stage in 45 litres pots, utilized in the drought resistance trial, and in a container (25 x 0.8 m), utilized in the high temperature resistance trial. In drought resistance trial, two water regimes were applied: 1) Control, soil humidity was kept at the field capacity, 2) W1, pots water losses were reintegrated at 80%. Above ground plant biomass, net photosynthesis, transpiration rate, stomatal conductance, leaf relative water content (RWC) were monitored throughout both trials

    Coupling lipid nanoparticle structure and automated single particle composition analysis to design phospholipase responsive nanocarriers

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    Lipid nanoparticles (LNPs) are versatile structures with tunable physicochemical properties that are ideally suited as a platform for vaccine delivery and RNA therapeutics. A key barrier to LNP rational design is the inability to relate composition and structure to intracellular processing and function. Here we combine Single Particle Automated Raman Trapping Analysis (SPARTA®) with small angle scattering (SAXS / SANS) techniques to link LNP composition with internal structure and morphology and to monitor dynamic LNP - phospholipase D (PLD) interactions. Our analysis demonstrates that phospholipase D, a key intracellular trafficking mediator, can access the entire LNP lipid membrane to generate stable, anionic LNPs. PLD activity on vesicles with matched amounts of enzyme substrate was an order of magnitude lower, indicating that the LNP lipid membrane structure can be used to control enzyme interactions. This represents an opportunity to design enzyme-responsive LNP solutions for stimuli-responsive delivery and diseases where PLD is dysregulated
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