The responses of leaf litter invertebrates to environmental gradients along road edges in subtropical island forests

Knowledge of how roads affect forest biodiversity can be improved by measuring the responses of indicator species to complex environmental gradients caused by these infrastructures. We studied litter invertebrate species responses to road edges in laurel and pine forests in Tenerife, Canary Islands. We sampled invertebrates from litter and assessed the environmental variation related to road proximity. We also assessed the effect of relevant environmental predictors on a diverse array of potential indicator species. We applied canonical ordination and non-parametric regression (Lowess) to classify invertebrate species responses to roads and their associated gradients. Three types of responses to road edge proximity were defined for the most common invertebrate taxa: edge-preferring or edge specialists, interior-preferring or edge-avoiders, and edge-indifferent or neutral species. Those species appearing most frequently and with higher population density between 1 and 20 m from the edge (commonly peaking at 10 m from the road) were categorized as edge-preferring. We classified taxa attaining peak population densities at or beyond 60 m from the edge (and most commonly 100 m) as interior species. Edge-neutral species were those without an evident pattern of stabilization in abundance along the gradient and with peaks in abundance at varying distance intervals. These edge litter communities contain a high native and endemic diversity but also a significant density of alien fauna. The specific patterns of penetration of road edge effects on invertebrate species should be seen as having a pervasive and cumulative impact considering the exceptionally large number of roads in these forests and the high population densities of alien invertebrates. Future management plans for forest conservation on the Canary Islands should include the highly altered but valuable litter communities along road edges.     

Detection of Gibellina cerealis infection on winter common wheat in Ukraine

Journal of Plant Diseases and Protection - False eyespot disease caused by Gibellina cerealis (Pass.) Pass. was first detected in Ukraine during field inspections of wheat canopies in...     

Effect of annealing from traditional nixtamalisation process on the microstructural,thermal, and rheological properties of starch and quality of pozole

Eleven maize landraces were evaluated for pozole quality. The microstructural, thermal and rheological properties of annealed starch granules determine most of the quality of pozole. Annealed starch in traditional nixtamalisation has an important role in increasing gelatinisation onset (To), peak (Tp) and final (Tf) temperatures; peak, setback and final viscosity as well as the stability of the starch granule, all of which significantly affect pozole quality. Annealed starch in Cacahuacintle nixtamal (pozole end-use) increased temperatures To, Tp and Tf by >5.2, >3.8 and >4.1 °C respectively, and narrowed the range Tf − To from 13.78 to 12.62 °C. The enthalpy was reduced from 6.76 to 5.85 J/g, while the nixtamal starch in tortilla maize landraces presented fewer annealing effects. The annealing effect in nixtamal starch seems to stabilize the starch granules and avoid their collapse, compared to native starch, as shown by the X-ray diffraction peak intensity and pattern that is similar to unprocessed maize. Starch in nixtamal changes from Type A to Type V pattern in pozole. Kernel physical parameters, although important, affected the quality to a lesser extent, with the exception of the flotation index. Cacahuacintle maize landrace showed the best quality and yield as well as a short pozole cooking time.     

Influence of Fucoidans on Hemostatic System

Three structurally different fucoidans from the brown seaweeds Saccharina latissima (SL), Fucus vesiculosus (FV), and Cladosiphon okamuranus (CO), two chemically modified fucoidans with a higher degree of sulfation (SL-S, CO-S), and a synthetic totally sulfated octasaccharide (OS), related to fucoidans, were assessed on anticoagulant and antithrombotic activities in different in vitro experiments. The effects were shown to depend on the structural features of the compounds tested. Native fucoidan SL with a degree of sulfation (DS) of 1.3 was found to be the most active sample, fucoidan FV (DS 0.9) demonstrated moderate activity, while the polysaccharide CO (DS 0.4) was inactive in all performed experiments, even at high concentrations. Additional introduction of sulfate groups into fucoidan SL slightly decreased the anticoagulant effect of SL-S, while sulfation of CO, giving rise to the preparation CO-S, increased the activity dramatically. The high level of anticoagulant activity of polysaccharides SL, SL-S, and CO-S was explained by their ability to form ternary complexes with ATIII-Xa and ATIII-IIa, as well as to bind directly to thrombin. Synthetic per-O-sulfated octasaccharide OS showed moderate anticoagulant effect, determined mainly by the interaction of OS with the factor Xa in the presence of ATIII. Comparable tendencies were observed in the antithrombotic properties of the compounds tested.     

Occurrence and distribution study of residues from pesticides applied under controlled conditions in the field during rice processing

The results of an experiment to study the occurrence and distribution of pesticide residues during rice cropping and processing are reported. Four herbicides, nine fungicides, and two insecticides (azoxystrobin, byspiribac-sodium, carbendazim, clomazone, difenoconazole, epoxiconazole, isoprothiolane, kresoxim-methyl, propanil, quinclorac, tebuconazole, thiamethoxam, tricyclazole, trifloxystrobin, λ-cyhalotrin) were applied to an isolated rice-crop plot under controlled conditions, during the 2009-2010 cropping season in Uruguay. Paddy rice was harvested and industrially processed to brown rice, white rice, and rice bran, which were analyzed for pesticide residues using the original QuEChERS methodology and its citrate variation by LC-MS/MS and GC-MS. The distribution of pesticide residues was uneven among the different matrices. Ten different pesticide residues were found in paddy rice, seven in brown rice, and eight in rice bran. The highest concentrations were detected in paddy rice. These results provide information regarding the fate of pesticides in the rice food chain and its safety for consumers.     

Evaluation of the Influence of Multiple Environmental Factors on the Biodegradation of Dibenzofuran, Phenanthrene, and Pyrene by a Bacterial Consortium Using an Orthogonal Experimental Design

For a bioremediation process to be effective, we suggest to perform preliminary studies in laboratory to describe and characterize physicochemical and biological parameters (type and concentration of nutrients, type and number of microorganisms, temperature) of the environment concerned. We consider that these studies should be done by taking into account the simultaneous interaction between different factors. By knowing the response capacity to pollutants, it is possible to select and modify the right treatment conditions to enhance bioremediation.     

Phoretic dispersal of the entomopathogenic nematode Heterorhabditis amazonensis by the beetle Calosoma granulatum

Entomopathogenic nematodes (EPN) have limited ability to travel and need to adopt alternative strategies to reach hosts that are far away. They can attach themselves to an organism that acts only as a dispersal agent to transport the EPN to places that they cannot reach by themselves. The larval and adult stages of Calosoma granulatum (Coleoptera: Carabidae) beetle are important predators of caterpillars that live in the soil of Brazilian agricultural systems. The nematode Heterorhabditis amazonensis (Rhabditida: Heterorhabditidae) is a native of Brazil and plays a major role in the control of Spodoptera frugiperda (Lepidoptera: Noctuidae) caterpillars. This study assessed the ability of C. granulatum to carry and disperse H. amazonensis. The experimental arenas consisted of two types of containers with substrate connected by a plastic tube through which the insects could move freely. Only one of the containers received infective juveniles (IJ) and the other was used as the test container. We first used C. granulatum larvae and adults to evaluate the influence of different concentrations of IJs on phoretic behavior. Then different distances traveled by the adult beetle were tested to measure their effect on IJ transport. The results showed that C. granulatum is a good phoretic dispersal agent and the transport of IJs by the larvae is less influenced than transport by the adult, by a change in the IJ concentration. The distance traveled by the adult influences the number of EPN carried and the detection of phoresy even at greater distances (40 cm) indicates that C. granulatum is capable of transporting the EPN for distances greater than those evaluated.     

Evaluation of partial root-zone drying for potential field use as a deficit irrigation technique in commercial vineyards according to two different pipeline layouts

The use of partial root-drying (PRD) irrigation implies doubling pipelines instead of using a conventional single pipeline. However, pipelines can be spaced a short distance apart (e.g. 1 m) along the vine row (“D” layout) or joined with cable ties and laid as a single pipeline (“S” layout). Pipelines in “S” configuration are laid under the vine row, and in “D” at both sides of the vine row. These two different layouts can change the wetted soil zone and affect grapevine response to irrigation. The focus of this study was therefore on establishing the role of pipeline layout in vine-grape (cv. ‘Tempranillo’) response under semi-arid conditions in which PRD is managed as a deficit irrigation technique. Six irrigation treatments were applied, which resulted from the combination of Control (C, full irrigation), PRD and seasonal sustained deficit irrigation (SSDI), and “S” and “D” pipeline layouts. SSDI and PRD were irrigated to 50% C throughout the irrigation season, and C irrigation was scheduled according to a crop water balance technique. Midday stem water potential (Ψ_stem) and leaf conductance (g_l) indicated that, on the whole, PRD treatments had a slightly higher water status than SSDI treatments, but a substantially lower status than C treatments. Use of the “D” pipeline layout significantly reduced Ψ_stem in both PRD and SSDI treatments and in some instances for Control conditions, too. Berry yield, vine intercepted radiation, leaf abscisic acid (ABA) and g_l were highly correlated with Ψ_stem. Differences in water status between PRD-S and SSDI-S, according to a sub-surface irrigation test, seemed to be more related to changes in soil evaporation losses and irrigation efficiency than to any intrinsic PRD effect. PRD-S accounted for water savings equivalent to 10% according to the ratio between applied water and grape production for the SSDI-S treatment, whereas PRD-D berry yield was not significantly different from that associated with the SSDI-S treatment. In conclusion, under the growing conditions of this experiment, PRD-S offered the possibility of slightly improving water conservation when irrigation was applied to the soil surface.     

The role of weather and density dependence on population dynamics of Alpine‐dwelling red deer

The dynamics of red deer Cervus elaphus populations has been investigated across different environmental conditions, with the notable exception of the European Alps. Although the population dynamics of mountain‐dwelling ungulates is typically influenced by the interaction between winter severity and density, the increase of temperatures and the reduction of snowpack occurring on the Alps since the 1980s may be expected to alter this pattern, especially in populations dwelling at medium ‐ low elevations. Taking advantage of a 29‐year time series of spring count data, we explored the role of weather stochasticity and density dependence on growth rate and vital rates (mortality and weaning success), and the density‐dependent variation in body mass in a red deer population of the Italian Alps. The interaction between increasing values of density and snow depth exerted negative and positive effects on growth and mortality rates, respectively, while weaning success was negatively affected by increasing values of density, female‐biased sex ratio and snow depth. Body mass of males and females of different age classes declined as population size increased. Our data support the role of winter severity and density dependence as key components of red deer population dynamics, and provide insight into the species' ecology on the European Alps. Despite the recent decline of snowpack on the Alpine Region, the negative impacts of winter severity and population abundance on growth rrate (possibly mediated by the density‐dependent decline in body mass) confirms the importance of overwinter mortality in affecting the population dynamics of Alpine‐dwelling red deer.