Biostimulation as a process aiding tebuconazole degradation in soil

Purpose

The purpose of this study was to compare effects of two biostimulating substances (compost and bird droppings) on the proliferation of microorganisms, enzymatic activity, and resistance of spring barley in soil exposed to tebuconazole fungicide. Both biostimulating substances were also assessed for their efficacy in tebuconazole degradation in soil.

Materials and methods

A pot vegetation experiment was performed with soil belonging to the Eutric Cambisols to test the effect of tebuconazole on the biological activity of soil. Its adverse effect on the biological properties of soil was minimized through the use of biostimulating substances (compost and bird droppings), the effect of which was expressed with the IF_C/BD index. The RCh index was used to determine the effect of tebuconazole on the proliferation of soil microorganisms and enzymes, the BA₂₁ index was used to express soil fertility based on the activity of soil enzymes, whereas the RS index—to express the resistance of spring barley to the administered doses of tebuconazole. Finally, analyses were conducted to determine the efficacy of soil amendment with biostimulating substances in tebuconazole degradation.

Results and discussion

Study results demonstrate that tebuconazole caused significant changes in the proliferation of the tested groups of microorganisms, in the activity of soil enzymes, and in spring barley yield. It was especially noticeable in pots in which the soil was exposed to its highest dose, i.e., 2.499 mg kg^?1. Soil supplementation with bird droppings had a positive effect on the development of soil microorganisms and on the enzymatic activity in the soil. In turn, compost addition to soil exerted various effects on the biological properties of soil. Both biostimulating substances failed to improve spring barley yield. Tebuconazole degradation was more intense in the soil fertilized with bird droppings than with compost.

Conclusions

Results of this study suggest that tebuconazole can affect the stability and health status of soil ecosystems by modifying their biological properties. The high sensitivity of soil microorganisms and enzymes to stress conditions makes them reliable environmental bioindicators. The strive for eliminating the adverse impact of fungicides on soil microbiome through the use of appropriate remediation methods, like, e.g., biostimulation, is of greater concern from the ecological perspective.

     

Species selection maintains self-incompatibility

Identifying traits that affect rates of speciation and extinction and, hence, explain differences in species diversity among clades is a major goal of evolutionary biology. Detecting such traits is especially difficult when they undergo frequent transitions between states. Self-incompatibility, the ability of hermaphrodites to enforce outcrossing, is frequently lost in flowering plants, enabling self-fertilization. We show, however, that in the nightshade plant family (Solanaceae), species with functional self-incompatibility diversify at a significantly higher rate than those without it. The apparent short-term advantages of potentially self-fertilizing individuals are therefore offset by strong species selection, which favors obligate outcrossing.     

Examining heterogeneity in the diagnostic accuracy of culture and PCR for Salmonella spp. in swine: a systematic review/meta-regression approach

The accuracy of bacterial culture and PCR for Salmonella in swine was examined through systematic review of existing primary research in this field. A replicable search was conducted in 10 electronic databases. All steps of the review were conducted by two reviewers: to identify relevant publications, to assess their methodological soundness and reporting, and to extract raw data or reported test accuracy estimates. Meta-analyses and meta-regression were performed: to evaluate pooled estimates of test sensitivity (Se) and specificity (Sp), to identify variables explaining the variation in reported test estimates, and to evaluate the association between these variables and reported test Se and Sp. Twenty-nine studies were included in the review. Unique test evaluations reported in these 29 studies were categorized according to the type of test comparison: culture versus culture (n = 134 test evaluations) and PCR versus culture (n = 21). We identified significant heterogeneity among evaluations for each test category. For culture, more heterogeneity was caused by differences in individual test protocols (52%) than overall differences between studies (16%). Enrichment temperature, study population, agar and enrichment type were significantly associated with variation in culture Se. Furthermore, interaction between enrichment temperature and enrichment type was detected. For PCR, most of the heterogeneity was caused by overall differences between studies (65-70%); sample type and study size were associated with variation in reported PCR Se and Sp. The overall methodological soundness and/or reporting of primary studies included in this review were poor, with variable use of reference standards, and consistent lack of the use or reporting of blinding, randomization and subject (sample) selection criteria. Consequently, the food safety and veterinary public health research community should formally consider ways for standardizing the conduct and reporting of this type of research.     

The study of coloration and antibacterial efficiency of corona activated dyed polyamide and polyester fabrics loaded with Ag nanoparticles

The aim of this study was to examine the influence of dyeing on antibacterial efficiency of corona activated polyamide and polyester fabrics loaded with colloidal Ag nanoparticles as well as the influence of the presence of Ag nanoparticles on the color change of dyed fabrics. C.I. Acid Green 25 and C.I. Disperse Blue 3 were used for dyeing of polyamide fabrics and C.I. disperse violet 8 for polyester fabrics. The color change of polyamide fabrics depends on the dye type, which was generally lower compared to polyester fabrics. Antibacterial efficiency of Ag loaded fabrics was tested against Gram-positive bacterium Staphylococcus aureus and Gram-negative bacterium Escherichia coli. Corona activated polyester and polyamide fabrics showed excellent antibacterial efficiency independently of order of dyeing and Ag loading. The morphology of fibers loaded with Ag nanoparticles was assessed by SEM and atomic absorption spectroscopy for elemental analysis.     

Application of artificial neural network (ANN) for prediction of fabrics’ extensibility

In the field of clothing technology, prediction of the fabric properties is very important because the fabric is the basic element of every clothing item. Knowing the fabric properties it is possible to predict fabrics’ behaviour during process of clothing manufacturing (in phase of cutting, sewing and ironing) as well as clothing items’ behaviour during usage. According to the fabrics’ characteristics and model design it is possible to predict appearances of the clothing items and their draping which can be presented with many computer simulations. In this paper extensibility of the fabric which appears during a small forces loading on the fabrics are investigated. Loading of small forces on the fabric appears in each phases of clothing manufacturing processes and during usage of clothing items. Investigations are managed on 50 fabrics which are weaving in twill weave and 100 % wool. The basic characteristics of fabric (density of warp and weft, mass per unit area, thickness) are defined according appropriate standard methods and tensile properties in the warp and weft directions are measured using KES-FB1 measuring system. Using an artificial neural network (ANN) prediction of extensibility properties of the fabrics are done, results are compared with experimental values and deviations are determined. ANN is an adaptive system that changes its structure based on external or internal information that flows through the network during the learning phase. They can be used to model complex relationships between inputs and outputs or to find patterns in data. Based on the implemented investigations, minimal deviations between experimental and predicted values are obtained and can be concluded that ANN can be used for prediction of the fabrics properties.     

Chestnut blight fungus in Croatia: diversity of vegetative compatibility types,mating types and genetic variability of associated Cryphonectria hypovirus 1

In order to improve understanding of its diversity, 338 isolates of Cryphonectria parasitica, the causal agent of chestnut blight, were sampled from 10 chestnut populations throughout chestnut‐growing coastal and continental areas of Croatia. Eighteen vegetative compatibility (VC) types were identified. The VC type EU‐1 was the most widespread, comprising 42·9% of the isolates, followed by EU‐2 (21%) and EU‐12 (14·2%). In respect to the occurrence of the main VC types, the C. parasitica populations in Croatia combined features of both northwestern and southeastern European populations. Perithecia and mating‐type ratios of approximately 1 : 1 were found in all populations, suggesting that sexual reproduction of the fungus is common in Croatia. Natural hypovirulence was also evident in all populations, with incidence of hypovirus‐infected isolates ranging from 12·7% in Istria‐Buje to 66·6% in the continental part of the country. A total of 36 hypovirus‐infected isolates sampled throughout Croatia were analysed in ORF‐A and ORF‐B by RT‐PCR/RFLP analysis. All viral isolates belonged to the Italian subtype of Cryphonectria hypovirus 1 (CHV‐1) and were closely related to the isolates found in other European countries. The RFLP patterns found were also identical or similar to the patterns of three isolates collected in Croatia 22 years ago, suggesting a slow evolution of the hypovirus.     

Significant breeding properties of inbred maize lines as the basis for creating new,higher yielding hybrids

Data are given on the dynamics of water loss from grain of elite maize lines during ripening and on their photosynthetic-fluorescence properties based on the effects and nature of structural and functional changes in thylakoid membranes and chemical structures of grain tissues.     

An Evaluation of the Effectiveness of Sorbents in the Remediation of Soil Contaminated with Zinc

Zinc exerts negative effects on soil and contributing to the degradation of soil ecosystems. New solutions for restoring healthy soil activity are therefore needed. The aim of this study was to evaluate the effectiveness of sorbents in the biological remediation of soil contaminated with zinc. A pot experiment was conducted on loamy sand. The tested plant was maize (Zea mays). Soil was contaminated with zinc chloride doses of 0, 100, 300, and 900 mg Zn²⁺ kg^?1 DM soil (dry matter of soil). Alginate, biochar, sepiolite, calcined halloysite, and a molecular sieve were added to soil in amounts corresponding to 2.5% of soil weight to minimize zinc’s potentially toxic effects on the biological properties of soil. The application of zinc stimulated the proliferation of all analyzed microbial groups. Zinc exerted negative effects on the ecophysiological diversity (EP) of fungi and the activity of dehydrogenases, catalase, and acid phosphatase. The applied sorbents modified the microbiological and biochemical properties of soil. In zinc-contaminated soil, alginate, biochar, and molecular sieve increased the counts of organotrophic, oligotrophic, and actinobacteria. Sorbents were not highly effective in promoting fungal growth and exerted varied effects on the activity of soil enzymes. The molecular sieve stimulated the activity of all soil enzymes, excluding β-glucosidase. Alginate minimized the negative influence of zinc on dehydrogenases and acid phosphatase, and biochar—on catalase, sepiolite, and calcined halloysite —on acid phosphatase. By modifying the biological properties of soil, the tested sorbents contributed to an increase in maize yields and a decrease in zinc uptake by maize plants.     

Examining the Effects of the Destroying Ammunition,Mines and Explosive Devices on the Presence of Heavy Metals in Soil of Open Detonation Pit; Part 2: Determination of Heavy Metal Fractions

As a result of the destruction of ammunition, mines, and explosive devices by the method of open detonation, the increased concentration of heavy metals is often recorded in the soil of military polygons, which is a serious ecological problem. However, in order to determine the potential risk of such locations to the environment, it is necessary to determine, in addition to the total content, the forms in which the metals are present. In this paper, a sequential extraction method was used to analyze the six fractions of five heavy metals (cadmium, lead, nickel, copper, and zinc) in the soil of the polygon for destruction of ammunition, mines, and explosive devices. Samples were collected from the place of direct detonation (so-called pits) and from the edge of the pit. The aim of this research is determination of metal speciation in order to obtain a better insight in their mobility and risk arising from this. The results showed that heavy metals are predominantly present in the residual, oxide, and organic fractions. Cd and Cu were also significantly present in the mobile fractions due to conducted activities on the polygon. To assess the potential environmental risk of soil, the risk assessment code (RAC) and individual (ICF) and global (GCF) contamination factors were used. According to the RAC, the mobility and bioavailability of the analyzed heavy metals decreases in the following order: Cd?>?Cu?>?Zn?>?Pb?>?Ni. ICF results show low to moderate risk, while GCF results show low risk in terms of heavy metal contamination in the examined area.     

Effects of early leaf removal on grape yield,chemical characteristics,and antioxidant activity of grape variety Cabernet Sauvignon and wine from eastern Croatia

The aim of this study was to determine the impact of two different treatments of early defoliation performed before blooming on: grape yield, chemical parameters, polyphenols content, and antioxidant activity of grape and red wine cv. Cabernet Sauvignon from the vineyard located in Ilok, the eastern continental region of Croatia. Two different treatments of leaf removal (LR) were performed: removal of 3 leafs (T1) and 6 leafs (T2) before blooming, together with control (no leaf removal) (T3) during two years (2013 and 2014). Crop yield and average cluster weights per vine were determined. Density, pH and titratable acidity were measured in must, while the total phenols, total anthocyanins and antioxidant activity were measured in the extract of grape skin and produced wine. The analysis of individual anthocyanins in wine was performed by HPLC method. T2 treatment significantly lowered the crop yield and the average cluster weights, and increased total phenols, total anthocyanins, antioxidant activity and most abundant individual anthocyanins in wine. Defoliation did not affect the other chemical parameters in must, grape skin extract and wine. Vintage year is statistically the most significant source of variability for density of must, antioxidant activity in grape skin extract, as well as pH and titratable acidity in wine. This study has showed that the early leaf removal treatment in eastern continental part of Croatia could be used for the production of smaller quantity of high quality Cabernet Sauvignon red wine abundant with anthocyanins.