RESUMEN
According to their nutritional value, their ability to adapt to the various environmental conditions, and their versatility, cereals are among the most cultivated plants in the world. However, the ongoing climate changes subject crops to important environmental stress that for some varieties leads to high production losses. Therefore, the selection of species and varieties that are more versatile and adaptable to different environmental conditions can be important. However, the characteristics of some cereals are not completely known; this is a priority before aiming to improve their cultivation. The aim of this study is to characterize select species that are potentially suitable for local environmental conditions and that possess nutritional value. The elemental composition was assessed in different cereal species grown following intensive and organic agriculture practices. Six species were grown for this study with techniques of intensive agriculture: Triticum monococcum L., Triticum dicoccum L., Triticum aestivum L., variety Verna, Triticum durum Desf., variety Senatore Cappelli, Triticum durum Desf., variety Claudio, and Avena strigosa Schreb.; four of these were also grown following organic procedures: Triticum monococcum L., Triticum dicoccum L., Triticum aestivum L., variety Verna, and Triticum durum Desf., variety Senatore Cappelli. The study considered twenty elements, including major nutrients (Ca, K, Mg, P, and S), seven micronutrients (B, Cu, Fe, Mn, Mo, Se, and Zn), and trace elements with toxic properties (Al, Ba, Cd, Cr, Na, Rb, Sc, and Sr) that can be accumulated at the seed level. The results highlight the differences in the element concentrations in the cereal seeds in relation to the genus and species; the highest concentrations of the major nutrients appeared in T. monococcum; the concentrations were 6.9, 2.09, 7.2, and 2.9 mg/g for K, Mg, P, and S, respectively. The highest concentrations of certain micronutrients, B, Ca, Mo, and Se (16, 785, 3.69, and 0.34 µg/g), were in A. strigosa. There is also evidence that the element content can be affected by the adopted cultivation procedure; however, the effects of the growing procedure can be significantly different when different species are considered. T. monococcum, grown by an organic procedure, presented lower concentrations of the major nutrients, while it demonstrated a modest increase in the micronutrients in the T. durum variety organic S. Cappelli, and the production procedure did not affect the elemental composition of the T. aestivum variety Verna. The survey also highlights that the studied species and the growing procedure affected the capacity to accumulate and translocate trace hazardous elements for human health at the seed level.
Asunto(s)
Grano Comestible , Triticum , Grano Comestible/química , Triticum/química , Agricultura Orgánica , Valor Nutritivo , Oligoelementos/análisis , Productos Agrícolas/química , Productos Agrícolas/crecimiento & desarrolloRESUMEN
BACKGROUND AND AIMS: The structure of plant communities, which is based on species abundance ratios, is closely linked to ecosystem functionality. Seed germination niche plays a major role in shaping plant communities, although it has often been neglected when explaining species coexistence. The aim of this work is to link the seed germination niche to community ecology, investigating how functional seed traits contribute to species coexistence. METHODS: Species selection was based on a database of 504 vegetation surveys from the Veneto coast (Italy). Through cluster analysis we identified the foredune community and selected all of its 19 plant species. By using the 'Phi coefficient' and frequency values, species were pooled in different categories (foundation species, accidental species of the semi-fixed dune and aliens), then the 19 species were grouped according to their germination responses to temperature and photoperiod through cluster analyses. For each germination cluster, we investigated germination trends against temperature and photoperiod by using generalized linear mixed models. KEY RESULTS: We identified four germination strategies: (1) high germination under all tested conditions ('high-germinating'); (2) high germination at warm temperatures in the dark ('dark warm-cued'); (3) high germination at warm temperatures in the light ('light warm-cued'); and (4) low germination, regardless of conditions ('low-germinating'). Foredune foundation species showed a narrow germination niche, being 'low-germinating' or 'dark warm-cued'. Annual species of semi-fixed dunes were 'high-germinating', while alien species were the only members of the 'light warm-cued' cluster. CONCLUSIONS: Our research suggests that different categories of species have dissimilar seed germination niches, which contributes to explaining their coexistence. Climatic events, such as rising temperature, could alter germination patterns, favouring seed regeneration of certain categories (i.e. alien and semi-fixed dune species) at the expense of others (i.e. foundation species, pivotal to ecosystem functioning), and hence potentially altering the plant community structure.
Asunto(s)
Ecosistema , Germinación , Italia , Semillas , TemperaturaRESUMEN
Invasive alien plants are a major threat to biodiversity and they contribute to the unfavourable conservation status of habitats of interest to the European Community. In order to favour implementation of European Union Regulation no. 1143/2014 on invasive alien species, the Italian Society of Vegetation Science carried out a large survey led by a task force of 49 contributors with expertise in vegetation across all the Italian administrative regions. The survey summed up the knowledge on impact mechanisms of invasive alien plants in Italy and their outcomes on plant communities and the EU habitats of Community Interest, in accordance with Directive no. 92/43/EEC. The survey covered 241 alien plant species reported as having deleterious ecological impacts. The data collected illustrate the current state of the art, highlight the main gaps in knowledge, and suggest topics to be further investigated. In particular, the survey underlined competition as being the main mechanism of ecological impact on plant communities and Natura 2000 habitats. Of the 241 species, only Ailanthus altissima was found to exert an ecological impact on plant communities and Natura 2000 habitats in all Italian regions; while a further 20 species impact up to ten out of the 20 Italian administrative regions. Our data indicate that 84 out of 132 Natura 2000 Habitats (64%) are subjected to some degree of impact by invasive alien plants. Freshwater habitats and natural and semi-natural grassland formations were impacted by the highest number of alien species, followed by coastal sand dunes and inland dunes, and forests. Although not exhaustive, this research is the first example of nationwide evaluation of the ecological impacts of invasive alien plants on plant communities and Natura 2000 Habitats.
Asunto(s)
Ecosistema , Especies Introducidas , Biodiversidad , Italia , PlantasRESUMEN
Agricultural diversification and high-quality products deriving from sustainable crops such as hemp can represent a solution to revitalize marginal areas and reverse land abandonment. This study aimed at comparing four different hemp cultivars (Carmagnola Selezionata, "CS"; Futura 75, "FUT"; Felina 32, "FEL"; Secuieni Jubileu, "JUB") to provide information to select the best suited cultivar for cultivation in mountain marginal areas and for specific end-use applications. Hemp cultivars were cultivated in a single experimental field to compare their ecological and agronomic behavior (duration of life cycle phases, plant size and biomass allocation, and plant resource-use strategies). Through metabolomic analysis of both vegetative and reproductive parts of the plants we tested the presence of substances of nutraceutical interest and traced seed nutritional profile. The four cultivars had different ecological and agronomic behavior, and nutritional profile. We found several compounds with potential pharmaceutical and nutraceutical values in all parts of the plant (leaves, inflorescences, and stems). JUB resulted the most suitable for seed production while CS showed the highest content of bioactive compounds in flowers and leaves. FUT, showed the best suitability for multi-purpose cultivation, while FEL seemed to be not appropriate for the cultivation in mountain area. The multi-disciplinary approach we adopted was effective in distinguish across hemp cultivars and provided information to farmers for the selection of the best hemp cultivar to select. Hemp had a high potential for cultivation in marginal lands, demonstrating to be an economic resource due to its multi-purpose use and to the possibility to generate high-added values products. Our results could serve as a stimulus for the reintroduction of this culture in the study area and in other similar environments.
Asunto(s)
Cannabis , Flores , Inflorescencia , Suplementos Dietéticos , Hojas de la PlantaRESUMEN
Within-species variation is a key component of biodiversity and linking it to climatic gradients may significantly improve our understanding of ecological processes. High variability can be expected in plant traits, but it is unclear to which extent it varies across populations under different climatic conditions. Here, we investigated seed trait variability and its environmental dependency across a latitudinal gradient of two widely distributed dune-engineering species (Thinopyrum junceum and Calamagrostis arenaria). Seed germination responses against temperature and seed mass were compared within and among six populations exposed to a gradient of temperature and precipitation regimes (Spiekeroog, DE; Bordeaux, FR; Valencia, ES; Cagliari, IT, Rome, IT; Venice, IT). Seed germination showed opposite trends in response to temperature experienced during emergence in both species: with some expectation, in populations exposed to severe winters, seed germination was warm-cued, whereas in populations from warm sites with dry summer, seed germination was cold-cued. In C. arenaria, variability in seed germination responses disappeared once the seed coat was incised. Seed mass from sites with low precipitation was smaller than that from sites with higher precipitation and was better explained by rainfall continentality than by aridity in summer. Within-population variability in seed germination accounted for 5 to 54%, while for seed mass it was lower than 40%. Seed trait variability can be considerable both within- and among-populations even at broad spatial scale. The variability may be hardly predictable since it only partially correlated with the analyzed climatic variables, and with expectation based on the climatic features of the seed site of origin. Considering seed traits variability in the analysis of ecological processes at both within- and among-population levels may help elucidate unclear patterns of species dynamics, thereby contributing to plan adequate measures to counteract biodiversity loss.
RESUMEN
The monitoring of biodiversity has mainly focused on the species level. However, researchers and land managers are making increasing use of complementary assessment tools that address higher levels of biological organization, i.e. communities, habitats and ecosystems. Recently, a variety of frameworks have been proposed for assessing the conservation status of communities or ecosystems. Among the various criteria proposed, all the protocols suggest considering (i) spatial aspects (range and area), and (ii) qualitative aspects of specific structures and functions. However, changes to ecological function are difficult to quantify and many protocols end up by using qualitative criteria. The aim of this work was to test the efficacy of some plant community attributes for the detection of vegetation quality in sand dune plant communities. We chose plant community attributes that either help to distinguish a habitat from others (diagnostic components) or play a significant role in habitat function and persistence over time. We used a diachronic approach by contrasting up-to-date vegetation data with data from previous studies carried out within the same areas. Changes in species composition were detected through detrended correspondence analyses (detrended correspondence analyses), Multi-Response Permutation Procedures and Indicator Species Analysis, while structural changes were analyzed by comparing species richness, total species cover, ecological groups of species and growth forms through null models. Ecological groups such as native focal species and aliens, and growth forms proved their efficacy in discriminating between habitat types and in describing their changes over time. The approach used in this study may provide an instrument for the assessment of plant community quality that can be applied to other coastal ecosystems.