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Ontogenetic changes in swimming performance of a freshwater calanoid copepod
No full textMost studies of copepod swimming have focused on marine adults. Here we studied in detail the changes in morpho-kinematics properties of swimming throughout the entire life cycle of a freshwater calanoid copepod, Sinodiaptomus sarsi, to provide information on the adaptive significance of metamorphosis. We investigated how the swimming speed of nauplii (N1 to N6) and copepodites (C1 to C6) changes with body size and shape, the size and number of limbs involved in movement, and with the stroke frequency and angular amplitude of the limbs using high-speed video filming. The speed of routine swimming in nauplii decreased during growth due to a disproportionate increase in body size relative to the length of the appendages. All three pairs of appendages were used by nauplii only during escape jumps reaching a frequency and relative speed of 240 Hz and 100 body lengths per second, respectively. Copepodites swimming speed increased with body size and the number of thoracic swimming legs and reached up to 300 body lengths per second during escape jumps. Our comparative kinematic analysis showed that nauplii and copepodites represent two different morpho-kinematic types of locomotion organization, well adapted to their body size and the corresponding hydrodynamic swimming regim
Resilienza al cambiamento climatico: risposta fisiologica e qualitativa di nuove varietà di mirtillo allo stress idrico
No full textValorization of refined lignin fractions as green promoters in photochemical Atom Transfer Radical Addition reactions
Get PDFHerein, we report a novel green photochemical procedure for the direct functionalization of terminal olefins with radical precursors promoted by technical lignin architectures. Spruce Kraft lignin was initially subjected to solvent refining to achieve fractions presenting a controlled molecular weight and fully characterized structural features. The obtained fractions were then tested as photoinitiators for organic transformations under visible light irradiation. The results demonstrated that a low molecular weight refined lignin, namely, L-EtOAc, was able to successfully promote relevant photoinduced radical reactions, providing several densely functionalized alkyl halides (14 examples, up to 98% yield). Mechanistic investigations were also performed to understand the role of lignin architecture in the reaction pathway. This work proposes an innovative role for lignin in organic chemistry, laying the basis for a brand-new field for the valorization of cheap technical lignocellulosic byproducts, while opening new exciting scenarios concerning green photochemical processes
Parasite diversity in grey wolves (Canis lupus) from Tuscany, central Italy: a copromicroscopical investigation
Get PDFParasite monitoring is considered an important issue for wildlife conservation as well as for veterinary and public health. In Italy, data on endoparasites of the grey wolf (Canis lupus) are still limited. A copro-microscopical study was performed to investigate endoparasites of grey wolf communities in three Apennine natural reserves and a hilly area in northern Tuscany, central Italy. A total of 66 fresh faecal samples were collected and examined using the Mini-FLOTAC technique with a high-density flotation solution. Apparent prevalence and 95% confidence intervals (CI) were estimated for each parasite taxon, while true parasite prevalence rates were assessed for individual wolves identified after molecular analyses in one of the three natural areas (Apuan Alps Regional Park, AARP). Overall, a high prevalence of endoparasites was estimated (92.4%, 95% CI 83.2-97.5), and most samples were found positive for respiratory capillariids (81.8%), i.e., Eucoleus boehmi (66.7%) and Eucoleus aerophilus (31.8%), Sarcocystis spp. (36.4%) and hookworms (21.2%). Physaloptera spp. (7.6%), Toxocara canis (1.5%), Spirocerca lupi (1.5%) Crenosoma vulpis (1.5%), Angiostrongylus vasorum (1.5%), Opistorchis felineus (3%), Alaria alata (1.5%), Taeniids (12.1 %), and Cystoisospora spp. (6.1%) were also identified. Dicrocoelium dendriticum eggs and Demodex spp. mites were detected in few samples. No significant differences emerged between faecal and population prevalence for any of the parasite species identified in AARP. Findings from this study add new information on grey wolf endoparasite infections in Italy and confirm the high prevalence of respiratory capillariids circulating among wild canids in Europe. Our results highlight the important role grey wolves may play in the transmission of these capillariid species between wild and domestic canids as well as of potentially zoonotic parasites in examined areas. Moreover, some endoparasites identified in this study may negatively affect the health of infected wolves
Evaluation of foliar application of 1,3-β-glucan in grapevine: nutritional and vegetative aspects
No full textThe biostimulant ValenaTM Flow (VF), the unique source of 1,3-β-glucan (ßG) material derived from Kemin’s microalgae Euglena gracilis, known to elicit plant defense responses was tested in young vines in a greenhouse during the 2022-2023 period. The aim of the trial was focused on the evaluation of different doses of the product (32% 1,3-β-glucan, 2% zinc) sprayed by foliar application. Substances like 1,3- β-glucan are viewed as pathogen-associated molecular patterns by pattern recognition receptors present naturally in plant cells, meaning that its presence can be mistaken for pathogens by the plant, increasing a way to fight off potential pathogens, even if no real attack exists, enhancing the nutritional uptake favorable to plant growth. Three different treatments, replicated three times (6 plants/repetition), were compared in 2022: treated only with water (Water), 0.60 L ha-1 VF (224 ppm ßG), and 2 L ha-1 VF (748 ppm ßG). In 2023, two lower doses of the product – 0.15 and 0.30 L ha-1 VF (56 and 112 ppm ßG) – were added, reaching five different theses, and 90 vines. In both years of trial, vegetative and productive behavior were investigated, dividing plants into different organs (leaves, fine and coarse roots, shoots, and annual wood). Regarding mineral nutritional aspects, in both years, the contents in leaves, roots, shoots, and wood were analyzed. The effect of the biostimulant modified the color of the vegetation and the biomass produced by the plants. The epigeal organs showed similar growth to the untreated control, but significant increases of root biomass were observed with the use of the biostimulant. In 2023, the effect was evident proportionally to the dosage of the biostimulant applied, until 224 ppm ßG, decreasing when the highest dose was used. Significant increases of N, P, K, Ca, Mg, S, Fe, Mn, and B contents were recorded when the biostimulant was applied to the plant
Diverging trends in plant phenology and productivity across European mountains in a warming world
Get PDFGlobal warming is affecting phenology and productivity of terrestrial ecosystems, with large implications for carbon cycling. However, how plant phenological trends are shifting in climatically heterogenous mountains, and how these trends affect ecosystem productivity remains unclear. Using moderate resolution satellite data (500 m), we analyzed differences in phenological trends and productivity between vegetation types and along elevation in Europe’s major mountain ranges between 2001 and 2023. End-of-season shifts outpaced start-of-season changes in broadleaved forests (+0.15 vs. -0.05 d y−1), while patterns in natural grasslands were opposite (+0.03 vs. -0.23 d y−1). The magnitude of these shifts varied significantly with elevation: grassland spring phenology consistently advanced more at high than at low elevations, while broadleaved forest spring phenology exhibited mountain range-specific elevation responses—advancing more at low than at high elevations in the Alps and in the Carpathians, but not in the Pyrenees and in the Scandinavian Mountains. Autumn phenology of broadleaved forests showed greater delays at high than at low elevations, likely due to spring and summer droughts. Climate anomalies, calculated as Z-scores across the 23-year time-series, predicted phenological anomalies well (max R2 = 0.51), although trends in climate over 23 years and phenological variables were related only weakly (max R2 = 0.27), suggesting that plants adjusted to long-term differently than to short-term climate change. Growing season length (GSL) was strongly coupled with productivity (max R2 = 0.60), especially in “cold-limited” vegetation. Nonetheless, temporal trends in GSL and productivity were not related (R2 < 0.03). In the last 23 years, GSL significantly increased in only 22 % of forest and 16 % of grassland pixels, but productivity in 20 % of forest and 53 % of grassland pixels. Our results suggested that factors beyond GSL affect ecosystem productivity, indicating that longer growing seasons will not necessarily translate into increasing productivity across European mountain
A multi‐century meteo‐hydrological analysis in the Italian Alps: daily streamflow (1862–2022) at different time scales
Get PDFIn this paper, the second longest time series of daily hydrometric levels and streamflow for an Italian river, Adige, in the Italian Alps, also one of the longest worldwide and unpublished so far, is reconstructed and analyzed. Daily streamflow prior to 1923, when the official mean daily discharge was first published, is estimated based on daily water levels collected since January 1862, cross-section geometry, discharge, and surface velocity measurements at the hydrometric station of Trento. The main objective of this paper is the identification, attribution, and quantification of the impact of natural and anthropic factors on changes in streamflow in a mountain region with marked orographic and climatic gradients. The resulting 161-year-long time series, until December 2022, for this 9763 km2 catchment is firstly analyzed in search of trends and their statistical significance, spectral properties at different time scales and periods, changes in the monthly regime prior to and after the constructions of reservoirs. The observed −1.0 mm year−1 slope of the annual streamflow linear trendline is statistically significant and indicates a decline of −1.4% per decade of available streamflow in the river, similar to the one observed in nearby basins. The spectral analysis conducted with the wavelet transform indicates that a sudden change of spectral properties and trends of daily streamflow occurred inside the pre- and post-reservoir construction period and can be explained also as a result of a more environment-oriented legislation. A wavelet coherence spectrum between streamflow and teleconnection indices indicates the existence of a significant coherence with the Atlantic Multidecadal Oscillation only. The comparison with estimated actual reference evapotranspiration losses and temperature points out that the observed temperature increase is not sufficient to explain the observed hydrological losses, being precipitation almost constant over the observation period. The observed increase of 86 mm of hydrological losses over the last century is explained in terms of water withdrawals for agricultural, civil, and industrial needs (38 mm), enhanced evapotranspiration due to temperature increase (30 mm), expanded artificial lakes' surface (1 mm), the residual of 17 mm being attributed to land-use changes with afforestatio
First results of UV light produced by an autonomous rover to control the main apple diseases
No full textAn autonomous rover prototype equipped with UVC light panels — developed to protect vineyards from grapevine diseases — was tested for its effectiveness against major apple diseases in a field trial conducted in Trentino (Northern Italy). In the growing season 2024, trials were carried out in three organic apple orchards with different varieties. The autonomous prototype was used either to supplement or completely replace conventional plant protection treatments. The orchards featured a narrow fruit-wall training system for Opal and Inored Story varieties, and a spindle training system for Golden Delicious. Row spacing was 2.6 meters across all sites. No chemical treatments were applied to the Opal and Inored Story, as they are scab-resistant cultivars. In the case of Inored Story, an untreated control plot (receiving neither chemical nor UV treatment) was also included to assess the prototype’s effectiveness against powdery mildew. A different strategy was applied to Golden Delicious, a variety highly susceptible to apple scab. Here, the experimental treatments included: a standard chemical strategy, a combination of low chemical input and low UV dosage, a high UV dosage, and an untreated control. UV dosage was set by adjusting the rover’s speed rather than the intensity of the UV light. The first treatment took place in late March, when conditions began to favour primary scab infections, and the trial concluded in early June. After three treatments, the prototype experienced a mechanical failure and was out of service for four days. It was subsequently repaired and remained operational for the remainder of the trial. Efficacy was assessed using pseudo-replications to enable statistical analysis. Visual inspections were also conducted to check for any negative side effects on vegetation and fruit. Results showed no significant differences between the low and high UV dosages in controlling powdery mildew on Opal (Figure 1), as well as between UV-treated and untreated plots of Inored Story (Figure 2). Due to the rainy spring in 2024, apple scab infection in the untreated Golden Delicious plots was particularly severe (Figure 3), with widespread secondary infections emerging by June. Across all treatment strategies, nearly 100% of shoots in Golden Delicious plots were infected by scab. The average percentage of infected leaves showed significant differences among treatments (χ2 [3]=9.994; p=0.0186). The KruskalWallis test indicated a significant trend when the chemical standard was excluded from the analysis (χ2 [2]=6.140; p=0.0468). Similarly, the average fruit infection rate was clearly lower in the standard chemical treatment compared to the untreated control, while both UV-based treatments were less effective than the standard. Importantly, no negative side effects were observed on either the leaves or the fruit of each variety. The effects of UV radiation on the control of powdery mildew, by employing different radiation doses, should be further investigated. Given the environmental conditions during the trial — particularly favourable to the development of apple scab — the preliminary results of this study seem promising. Additional field trials, carried out throughout the entire growing season, will be necessary to further evaluate the efficacy of UV light on apple diseases and to understand how this technology could partially replace or complement conventional plant protection strategies. The use of UV light and autonomous equipment could be considered as part of precision crop protection strategies aimed at developing low input approaches for apple orchard