21 research outputs found
TRY plant trait database â enhanced coverage and open access
Plant traitsâthe morphological, anatomical, physiological, biochemical and phenological characteristics of plantsâdetermine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of traitâbased plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traitsâalmost complete coverage for âplant growth formâ. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and traitâenvironmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives
Spatial and genetic analysis of a flag shoot subpopulation of Erysiphe necator in italy
Erysiphe necator overwinters both as ascospores in cleistothecia and as mycelium in dormant buds of grapevines. Shoots developing from infected buds early in the growing season are covered with dense mycelium and are known as \u201cflag shoots\u201d. Combining epidemiological and
Cortesi et al. Phytopathology, page 2
genetic analyses, the objective of this study was to analyze the spatial and genetic structure of a flag shoot subpopulation of E. necator, as a way to assess the contribution of flag shoots as primary inoculum and to determine if the flag shoot subpopulations are clonal, with only one mating type. One vineyard in Tuscany, Italy, was surveyed intensively for flag shoots for eight years; isolations of E. necator were made from flag shoots for five years. We observed distinct disease foci developing around flag shoots early in epidemics, demonstrating a steep dispersal gradient of conidia and the importance of flag shoots as primary inoculum sources. Flag shoots were spatially aggregated within and between years, most likely as a result of short-distance dispersal of conidia from flags early in the season when dormant buds for the next year\u2019s shoots are formed and are susceptible to infection. The two mating types were found in 1:1 ratios in this flag shoot subpopulations. Genotypic diversity, based on ISSR markers, was high in all years, with only two haplotypes occurring twice, and subpopulations were genetically differentiated between years. Similarities between haplotypes were not spatially autocorrelated. One multilocus analysis of population structure is consistent with the hypothesis of random mating, but another is not. These results are not consistent with expectations for either a strictly clonal or strictly randomly mating flag shoot subpopulation. Instead, the hypothesis that the flag shoot subpopulation of E. necator may reproduce both clonally and sexually needs further testing
Innervation of the paralyzed laryngeal muscles by phrenic motoneurons : a quantitative study by light and electron microscopy
In the cat, inspiratory opening of the paralyzed glottis recovered after unilateral or bilateral reinnervation of the posterior cricoarytenoid (PCA) muscles by phrenic axons. The morphometric analysis of the regenerated recurrent laryngeal nerves (RLNs), showed that proliferation was abundant; 4 months after the nerve anastomosis, more than 500 myelinated axonal branches repopulated the RLNs. The mean diameter of motor axons (3.5 to 5.0 microns) was lower than in normal phrenic and RLN (8 to 10 microns), and the mean internode length was about half that of the normal RLN. Histochemical examination of the PCA muscle revealed that muscle fiber composition (44% type I and 56% type II muscle fiber) was fairly similar to that of normal PCA. The contraction time of the reinnervated muscles was as long as 60 msec at the time of movement recovery, but it shortened to 25 to 30 msec when the reinnervation time increased. These anatomical and functional results support the choice of the phrenic nerve for laryngeal reinnervation
Multimedialita' e nuove forme di didattica. Statistici ed esperti a confronto
Consiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7, Rome / CNR - Consiglio Nazionale delle RichercheSIGLEITItal