Authors:A. Aldaoude, A. Shoaib, E. Al-Shehadah, M. Rajeh, M. Jawhar and M.I.E. Arabi
Scald caused by Rhynchosporium secalis, is an economically important disease found worldwide. In order to profile genes and pathways responding to R. seclais infection, leaf transcriptomes before and after fungus inoculation in susceptible barley were compared using cDNA-AFLP technique. Transcriptional changes of 144 expressed sequence tags (ESTs) were observed, of which 18 have no previously described function. Functional annotation of the transcripts revealed a wide range of pathways including cell wall fortification, cytoskeleton construction and metabolic processes at different time points. Furthermore, the results of RT-PCR analysis on candidate genes, ABC transporters and lycine-specific demethylase were consistent with the cDNA-AFLP data in their expression patterns. Taken together, our data suggest that susceptible barley reprograms metabolic and biological processes to initiate a suitable response R. secalis infection.
Authors:N. A. Di Benedetto, M. Alfarano, M. N. Laus, R. Caporizzi, M. Soccio, C. Robbe, Z. Flagella and D. Pastore
Assessment of Antioxidant Capacity (AC) of foods is useful to consider cumulative/ synergistic action of all dietary antioxidants, thus providing a more integrated information than the simple sum of measurable antioxidants. Among the different AC assays, the QUENCHERABTS (QUick, Easy, New, CHEap and Reproducible) procedure is based on the direct reaction of ABTS•+ reagent with fine solid food particles without extraction of antioxidants. This assay is able to measure both soluble and insoluble antioxidants, that simultaneously come into contact with ABTS•+ molecules by either liquid–liquid or solid–liquid interactions, respectively. These interactions may change depending on the particle diameter. Usually, particles having 0.1–0.3 mm size are used. Here, AC was evaluated on whole flour (WF), derived from a mix of grains of ten durum wheat varieties, characterized by three different particle sizes: a smaller one, ≤0.2 mm (control, WF0.2), and two larger ones, ≤0.5 mm and ≤1 mm (WF0.5 and WF1, respectively). Moreover, a novel AC calculation procedure based on the slope value of the regression line of ABTS•+ response vs flour amount is presented in detail. The classical QUENCHERABTS procedure provided for WF0.2 an AC value of 42.0±2.7 μmol eq. Trolox/g d.w. A similar result was obtained for WF0.5 (38.3±0.9 μmol eq. Trolox/g d.w.), thus indicating that these large particles may be analyzed by the QUENCHERABTS assay provided that the “slope” calculation procedure is used. On the contrary, WF1 showed about half AC (20.3±0.2 μmol eq. Trolox/g d.w.), thus showing that very large particles cannot be used even adopting the “slope” calculation.
Survey of aphids on dicotyledonous herbaceous plants along the Hungarian highways on 33 sampling points revealed the presence of 14 aphid species on gymnosperm trees. The most frequent conifer species was: Pinus nigra J. F. Arnold 1785 (21 locations) followed by Pinus sylvestris L.1753, Picea abies (L.) H. Karst. (4 locations), Juniperus communis L. 1753 (3 locations) and Juniperus virginiana L. 1753 (1 location), Thuja occidentalis L.1753 (2 locations), Thuja plicata Donn ex D. Don (1 location).
Eulachnus agilis (Kaltenbach, 1843) was the most frequently collected aphid species on Pinus nigra, followed by Cinara brauni Börner, 1940, Cinara schimitscheki Börner, 1940, Eulachnus rileyi (Williams, 1911) and Cinara acutirostris Hille Ris Lambers, 1956. The less frequent Cinara species was Cinara piniphila (Ratzeburg, 1844) which is a new record for the Hungarian fauna. Pinus sylvestris accommodated three aphid species: Cinara intermedia Pašek, 1954 was the most frequent, followed by Cinara pinea (Mordvilko, 1895) and Eulachnus agilis. Picea abies accommodated Cinara piceae, Cinara pruinosa (Hartig, 1841), Cinara piceicola (Cholodkovsky, 1896) and Sacchiphantes abietis L. 1758. Juniperus communis and J. virginiana most frequently hosted Cinara juniperi (De Geer, 1773). Eulachnus agilis occurred once on Juniperus communis. A single aphid species Cinara tujafilina was found on Thuja occidentalis and Thuja plicata.
Authors:K. V. Kocheva, G. I. Georgiev, V. K. Kochev, K. Olšovská and M. Brestič
The potentials of an electrochemical and a physical technique for detection of physiological differences in three wheat cultivars under optimal growth conditions were outlined in the study. Electrolyte leakage kinetics was established by continuous measurements of conductivity of solutions in which leaf pieces were incubated for 24 hours. Impedance spectra were obtained from intact leaves at frequency range from 7 to 2010 Hz and 250 mV measuring voltage applied between two gold plated silicon substrates serving as electrodes. The obtained spectra were approximated by a model employing two ARC elements connected in series. Parameters of the previously described diffusion model based on time course conductivity measurements were inversely correlated with electrical impedance spectroscopy data, thus the genotype with highest ion leakage (cultivar Prelom) exhibited lowest impedance magnitude. It was concluded that the two methods were able not merely to distinguish the three studied cultivars but also to rank them in the same order based on their electrical properties.
Authors:A. Sarkar, R. C. Das, MD H. Rashid, M. Ali, M. S. Islam, T. Asaeda and Q. Wang
Isolates of Pestalozzia theae Saw. and Trichoderma spp. were collected from Bangladesh Tea Research Institute (BTRI) farm area, Bangladesh. The cultural morphology and antagonistic potentiality of Trichoderma spp. against grey blight pathogen Pestalozzia theae was studied for tea cultivation. The antagonistic potentiality of Trichoderma spp., against Pestalozzia theae showed maximum (inhibition 84.45±0.77%) after 72 hrs of inoculation under in vitro condition followed by 76.02±3.50% after 24 hrs of inoculation. This study revealed that Trichoderma strain was highly effective to control Pestalozzia theae, the causal agent of grey blight disease of tea.
Authors:Marijana Kosanić, Branislav Ranković and Tatjana Stanojković
In the present investigation the acetone extracts of three macroalgae, Cystoseira amentacea, Cystoseira barbata and Cystoseira compressa, were tested for antioxidant, antimicrobial and cytotoxic potential. As a result of the study, C. amentacea extract had more potent free radical scavenging activity (IC50 = 409.81 μg/mL) than C. barbata and C. compressa extracts. For reducing power, measured values of absorbance varied from 0.0352 to 0.8873. The IC50 values for superoxide anion scavenging activity for different extracts were 521.45–976.62 μg/mL. Total phenol and flavonoid contents in extracts were 39.96–81.28 μg PE/mg and 20.85–64.58 μg RE/mg respectively. Further, all three Cystoseira species exhibited a similar antimicrobial activity. The lowest MIC value (0.312 mg/mL) was shown in the extract obtained from C. compressa against Bacillus subtilis. Finally, extract of C. amentacea expressed the strongest cytotoxic activity toward tested cell lines with IC50 values ranging from 94.72 to 186.55 μg/mL. Based on these results, it can be stated that the tested macroalgae can be used as potential natural antioxidants and antimicrobial and cytotoxic agents.
In order to clarify the role of PlPMI3 resistance gene in sunflower differential lines D4 for differentiation the pathogenicity in Plasmopara halstedii (sunflower downy mildew), analyses were carried out in two groups including four pathotypes which overcome and do not overcome PlPMI3 (Pl gene has still not been mapped) resistance gene. Based on the reaction for the P. halstedii isolates to sunflower hybrids varying only in Pl resistance genes, there were no virulence differences for the two groups. Index of aggressiveness was calculated for pathogen isolates and revealed the presence of significant differences between isolates of races 304 and 314; however, there were no aggressiveness differences for 7xx races. Regarding the life-history trait and the genetic architecture of the pathogen: there were morphological and genetic variations for the four P. halstedii isolates without a correlation with pathogenic diversity. The importance of the PlPMI3 resistance gene to differentiate the pathogenicity in sunflower downy mildew was discussed.
Authors:P. Milanez-Almeida, T. Ulas, M. Pasztoi, S. Glage, K. Schughart, M. B. Lutz, J. L. Schultze and J. Huehn
Influenza A virus (IAV) infection causes an acute respiratory disease characterized by a strong inflammatory immune response and severe immunopathology. Proinflammatory mechanisms are well described in the murine IAV infection model, but less is known about the mechanisms leading to the resolution of inflammation. Here, we analyzed the contribution of CD11b+Ly6C++Ly6G− cells to this process. An accumulation of CD11b+Ly6C++Ly6G− cells within the lungs was observed during the course of IAV infection. Phenotypic characterization of these CD11b+Ly6C++Ly6G− cells by flow cytometry and RNA-Seq revealed an activated phenotype showing both pro- and anti-inflammatory features, including the expression of inducible nitric oxide synthase (iNOS) by a fraction of cells in an IFN-γ-dependent manner. Moreover, CD11b+Ly6C++Ly6G− cells isolated from lungs of IAV-infected animals displayed suppressive activity when tested in vitro, and iNOS inhibitors could abrogate this suppressive activity. Collectively, our data suggest that during IAV infection, CD11b+Ly6C++Ly6G− cells acquire immunoregulatory function, which might contribute to the prevention of pathology during this life-threatening disease.
Authors:Zong-Sheng Yuan, Fang Liu and Guo-Fang Zhang
Endophytic phosphorus- and potassium-solubilizing bacteria were screened from the root, rhizome, stem, and leaves of Moso Bamboo, and their diversity was analyzed using their 16S rDNA sequences. Twenty endophytic phosphorus and potassium-solubilizing bacteria were screened from 82 bamboo plants, among which the CT-B09-2, WYS-A01-1 and JL-B06 had higher activities in decomposing organophosphates. The three species showed a decomposition diameter/colony diameter (D/d) of 5.05, 4.19 and 2.95, respectively, and a solubilizing activity of 81.77 mg/L, 77.85 mg/L and 63.69 mg/L, respectively. JL-B06, WYS-A01-1 and CT-B09-2 had higher activities in decomposing inorganic phosphorus, with a decomposition diameter/colony diameter (D/d) of 2.34, 2.12 and 1.82, respectively, and a solubilizing activity of 30.58 mg/L, 38.89 mg/L and 48.35 mg/L, respectively. CT-B21, WYS-A03-1 and JL-B06 had higher activities in decomposing potassium, with a decomposition diameter/colony diameter (D/d) of 3.37, 4.84 and 4.33, respectively, and a solubilizing activity of 2.81 mg/L, 2.54 mg/L and 2.46 mg/L, respectively. The 16S rDNA sequence analysis showed that the 20 phosphorus- and potassium-solubilizing bacteria belong to 14 species from 10 genera, and mainly consist of Alcaligenes spp., Enterobacter spp. and Bacillus spp. Our results demonstrate the abundant diversity of endophytic phosphorus- and potassiumsolubilizing bacteria in Moso Bamboo.
Authors:Wesam I. A. Saber, Khalid M. Ghoneem, Abdulaziz A. Al-Askar, Younes M. Rashad, Abeer A. Ali and Ehsan M. Rashad
Stem canker and black scurf of potato, caused by Rhizoctonia solani, can be serious diseases causing an economically significant damage. Biocontrol activity of Bacillus subtilis ATCC 11774 against the Rhizoctonia diseases of potato was investigated in this study. Chitinase enzyme was optimally produced by B. subtilis under batch fermentation conditions similar to those of the potato-growing soil. The maximum chitinase was obtained at initial pH 8 and 30 °C. In vitro, the lytic action of the B. subtilis chitinase was detected releasing 355 μg GlcNAc ml−1 from the cell wall extract of R. solani and suggesting the presence of various chitinase enzymes in the bacterial filtrate. In dual culture test, the antagonistic behavior of B. subtilis resulted in the inhibition of the radial growth of R. solani by 48.1% after 4 days. Moreover, the extracted B. subtilis chitinase reduced the growth of R. solani by 42.3% when incorporated with the PDA plates. Under greenhouse conditions, application of a bacterial suspension of B. subtilis at 109 cell mL−1 significantly reduced the disease incidence of stem canker and black scurf to 22.3 and 30%, respectively. In addition, it significantly improved some biochemical parameters, growth and tubers yield. Our findings indicate two points; firstly, B. subtilis possesses a good biocontrol activity against Rhizoctonia diseases of potato, secondly, the harmonization and suitability of the soil conditions to the growth and activity of B. subtilis guaranteed a high controlling capacity against the target pathogen.
Authors:S. Tahmasebi, B. Heidari, H. Pakniyat and A. Dadkhodaie
The 1BL/1RS wheat-rye translocations had been used in wheat breeding programs worldwide. The objective of this study was to determine the effect of the 1BL/1RS translocation in SeriM82 /Babax recombinant population. 167 lines of this population were assayed under well-irrigated, terminal drought, heat and a combination of heat and drought stress conditions in two years. 5S rDNA and Iag95 markers were used to differentiate genotypes with or without the1BL/1RS translocation. Presence of 1BL/1RS translocation reduced grain yield (YLD), grain per spike (GSP) and grain per m2 (GM2). QTLs in 1 BL/1RS segments indicated increased thousand-grain weight (TGW), chlorophyll content, spikelet per spike (SPLS), spike compactness (SCOM) and awn length (AWL) but reduced YLD, GSP and GM2. The 1BL/1RS carrying lines’ response varied between assayed environments. Plants of drought trials were more affected by 1BL/1RS compared to others. Differences in the effects of 1BL/1RS and QTLs suggest that gene expression at translocation loci is restricted to specific environmental conditions. In general, the 1BL/1RS translocation could not be a suitable source of genetic diversity for enhancing grain yield under heat and drought stresses.
Though the interplay of grazing intensity and the availability of resources is a key driver in grassland composition, very few studies focused on trait changes after abandonment along productivity gradients. Through a comparative approach, we aimed to assess the context-dependent effects of long-term grazing cessation on functional composition and diversity in sub-Mediterranean grasslands. We hypothesized that variability of topography, soil and vegetation structure on a fine scale drives the trait-based dynamics after long-term abandonment, also influencing the patterns of functional diversity. On a calcareous mountain ridge of central Italy, we collected data on species cover and traits, site characteristics, soil depth and vegetation structure in 0.5 m × 0.5 m plots located in extensively grazed pastures and in grasslands abandoned since the early 1970s. We analysed patterns of species and traits in relation to environmental variables and management type, and trends in functional diversity (FD, Rao’s quadratic entropy) along a productivity gradient. We found that grazing cessation reduced the overall FD and that the direction of species and trait response after long-term grazing cessation were affected, on a fine scale, by the soil depth / productivity gradient. In dryer conditions, species and functional responses were less affected by abandonment, and were devoted to resistance to both stress and disturbance. In abandoned pastures we detected a significant decrease in FD with increasing productivity, leading to a shift from functional strategies devoted to grazing avoidance and tolerance to those devoted to competition for light and resource acquisition. This trend was related to the filtering effect of coarse tall grasses, which spread in highly productive conditions. In grazed grasslands, we detected an overall increasing trend of FD with increasing productivity, confirming the key role of extensive grazing in maintaining high levels of FD.
A survey was conducted to study the species of Asilidae (Diptera, Brachycera) in Fars province, southern Iran during year 2012. A total of 12 species belonging to 12 genera and 6 subfamilies Apocleinae, Asilinae, Dasypogoninae, Leptogastrinae, Ommatiinae and Stenopogoninae were collected and identified. Among them, Tolmerus paganus Becker, 1923 is recorded for the first time in Iran. Additionally one subfamily, two genera and four species are recorded for the first time from Fars province. Distributional data for each species are given. An updated list of all known species of Asilidae from Fars province is also included.
New data on distribution of 11 torymid wasp species (Hymenoptera, Chalcidoidea, Torymidae) from Fars province in South-Western Iran are provided. The genus Eridontomerus Crawford, 1907 and four species Adontomerus nesterovi Zerova, 1985, E. biroi Ruschka, 1923, Monodontomerus rugulosus Thomson, 1876 and Podagrion gibbum Bernard, 1938 are new records for Iran. Available data for each species and brief notes on host(s) and geographical distribution are also given.
Whiteflies (Hemiptera: Aleyrodidae) are some of the most potentially detrimental pests for agricultural crops and the ornamental plant industry in Iran. The present paper deals with the faunistic survey of whiteflies in two provinces of Iran, Khorasan and Semnan. During the survey a total of 16 species from 12 genera were collected and identified. Distribution data are given for the species.
Authors:J. Palazzini, V. Fumero, N. Yerkovich, G. Barros, M. Cuniberti and S. Chulze
Fusarium graminearum (Schwabe) is reported as the main causal agent of Fusarium head blight in Argentina. The disease causes great losses in humid and semi-humid regions of the world, reducing grain yield and quality. During 2012/13 harvest season, a severe epidemic occurred in Argentina. The aims of this work were to determine the F. graminearum incidence and deoxynivalenol accumulation in wheat grain and flour samples obtained from two of the main wheat growing regions from Argentina. Levels of the pathogen and deoxynivalenol content were correlated in heads, grains and flour. Out of 69 wheat grain samples, 55 (79.7%) showed deoxynivalenol levels between 0.4 and 8.5 μg/kg. Fusarium graminearum was the main species isolated, the isolation frequency ranged from 30 to 52% of the total grains analyzed. Correlations were observed between deoxynivalenol content, % of F. graminearum infection, presence of the pathogen in heads, grain and flour.
Authors:N. Passricha, R. Batra, R. K Behl and V. K Sikka
A stock of disomic chromosome substitution (DCS) lines having specific chromosome of wheat variety C591 substituted in the background of rest of Chinese spring chromosomes, were used to analyze grain yield components as a function of enzyme activity of ADP–glucose pyrophosphorylase (AGPase), a starch biosynthesis enzyme in wheat grains. Associations between yield characteristics, grain growth rate (GGR) and AGPase enzyme activity of DCS lines suggested a major involvement of chromosome 3A, 4B, 7D and 2D in a temperature dependent manner. Assessment of AGPase assay at different developmental stages such as 14, 21, 28 days post anthesis (DPA) embodied that gene(s) for this enzyme are present on specific chromosomes and operate at different stages of grain development. The DCS line with 7D chromosome has a major contribution in determining the grain starch content. In this line, AGPase enzyme activity was highest at 21 DPA and was the most crucial determinant in its high GGR. Line 4B performed well at only early stage (14 DPA) suggesting that line 4B AGPase requires a lower temperature range for activation as compared to 7D line. Line 3A had substantially reduced (40%) test weights revealing the presence of few down-regulatory elements on chromosome 3A to reduce the activity of AGPase. The DCS line 2D showed higher test weights and grain number than all other lines ascribed to a consistent AGPase activity along with an efficient mechanism for translocation of photosynthates from source to sink. The chromosome 2D shows positive relation with yield attributes therefore, it can be employed to improve wheat productivity via analytical breeding programme.
Synthesis of flavonoid compounds in plants is associated with their response to environmental stress; however, the way in which the transcription of the relevant structural genes is regulated in stressed plants is still obscure. Transcription of the ‘early’ flavonoid synthesis genes Chi-1 and F3h-1 in the wheat coleoptile was investigated by quantitative real-time PCR in seedlings exposed to 100 mM or 200 mM NaCl. Under mild stress, transcript abundance of both Chi-1 and F3h-1 was increased significantly after six days of exposure. Under severe stress, the level of transcription was the same or even lower than that seen in nonstressed seedlings. In non-stressed conditions, the transcription patterns of Chi-1 and F3h-1 were quite distinct from one another, whereas under stress they became similar. An observed alteration in structural genes regulation mode under stress conditions may optimize flavonoid biosynthesis pathway to produce protective compounds with maximum efficiency.
Authors:G. Bacaro, S. Maccherini, A. Chiarucci, A. Jentsch, D. Rocchini, D. Torri, M. Gioria, E. Tordoni, S. Martellos, A. Altobelli, R. Otto, C. G. Escudero, S. Fernández-Lugo, J. M. Fernández-Palacios and J. R. Arévalo
Invasion by alien plant species may be rapid and aggressive, causing erosion of local biodiversity. This is particularly true for islands, where natural and anthropogenic corridors promote the rapid spread of invasive plants. Although evidence shows that corridors may facilitate plant invasions, the question of how their importance in the spread of alien species varies along environmental gradients deserves more attention. Here, we addressed this issue by examining diversity patterns (species richness of endemic, native and alien species) along and across roads, along an elevation gradient from sea-level up to 2050 m a.s.l. in Tenerife (Canary Islands, Spain), at multiple spatial scales. Species richness was assessed using a multi-scale sampling design consisting of 59 T-transects of 150 m × 2 m, along three major roads each placed over the whole elevation gradient. Each transect was composed of three sections of five plots each: Section 1 was located on the road edges, Section 2 at intermediate distance, and Section 3 far from the road edge, the latter representing the “native community” less affected by road-specific disturbance. The effect of elevation and distance from roadsides was evaluated for the three groups of species (endemic, native and alien species), using parametric and non-parametric regression analyses as well as additive diversity partitioning. Differences among roads explained the majority of the variation in alien species richness and composition. Patterns in alien species richness were also affected by elevation, with a decline in richness with increasing elevation and no alien species recorded at high elevations. Elevation was the most important factor determining patterns in endemic and native species. These findings confirm that climate filtering reflected in varying patterns along elevational gradients is an important determinant of the richness of alien species (which are not adapted to high elevations), while anthropogenic pressures may explain the richness of alien species at low elevation.
Authors:G. Brownstein, C. Johns, A. Fletcher, D. Pritchard and P. D. Erskine
Ecotones, representing the transition zones between species or communities, have been suggested as focal points for detecting early shifts in vegetation composition due to anthropogenic impact. Here we examined if changes in ecotone location or properties can be used as reliable indicators of hydrological change in temperate wetland communities. We examined 38 woodland-wetland-woodland transitions, distributed across four sites with different anthropogenic disturbance histories and hydrological traits. We tested whether: 1) the ecotones are associated with environmental gradients, and 2) the location or properties of these ecotones change with disturbance history. Well-defined ecotones were associated with steep gradients in soil depth and soil moisture. Most ecotones showed a change in vegetation from hydrophytic to dryland species. There was also some evidence that in highly disturbed sites the link between ecotones and environmental gradients was less apparent. By sampling across boundaries we can better understand the factors controlling the distribution of species. This allows us to make better predictions about the impacts of anthropogenic change in wetland communities. By investigating the transitions between different vegetation communities we were able to highlight key indicators that could be used to monitor these ecologically sensitive and diverse wetland communities.
Sweet sorghum (Sorghum bicolor L. Moench cv. Róna) is a widely grown sugar crop that is used for bioenergy production. Since sorghum shows increased sensitivity to nutrient deficiency, the objective of this study was to reach an appropriate Cu level in plant tissues using various concentrations of Cu and ethylenediaminetetraacetic acid (EDTA) in order to enhance the photosynthetic activity and biomass production of plants. Copper accumulation increased in the root and stem of plants irrigated for 12 weeks with 0.1 μM CuCl2 both in the presence and absence of 300 μM EDTA and as a consequence, the plant-available Cu concentration in the soil extracts was lower at harvest. Although the copper content of leaves slightly increased, the transport of Fe and Mn, the microelements participating in light reactions of photosynthesis was negatively affected. In spite of this, 0.1 μM CuCl2 alone and with 200 or 300 μM EDTA enhanced the maximal CO2 assimilation rate (Amax) as a function of photon flux density (PPFD) and increased soluble sugar content in all plant parts. The dry mass of plants especially that of stems increased very significantly after 0.1 μM CuCl2 + 300 μM EDTA treatment. These results show that non-toxic concentration of copper in combination with suitable concentration of EDTA can enhance photosynthesis, biomass production, sugar content and the total copper accumulation in the shoot of sweet sorghum plants.
The effects of stand structure, tree species composition, proportion of habitat types and land use history on breeding bird assemblages in temperate mixed forests in Western Hungary were studied. The species richness, the abundance and the composition of the whole breeding bird assemblage and of some groups formed on the basis of nesting site and rarity were examined. Stand structural variables had the highest impact on the breeding bird assemblage, while tree species composition, the varying proportion of vegetation types and land use history had no significant effect. In the case of the species richness, the abundance and the composition of the whole assemblage, the most important variables were the mean diameter of trees, the vegetation cover of the forest floor and the dead wood volume. The explained variance in the linear models of different groups varied between 20% and 60%, and the relative importance of these three variables also differed considerably. These results indicate that forest management may considerably influence the diversity and the composition of birds, as all the structural elements affecting birds deeply depend on it. Within the shelterwood management system, the elongation of the rotation and regeneration periods, and the relatively high proportion of retention tree groups after harvest could contribute to the conservation of forest birds. Our results also showed that for the forest bird communities, both the prevalence of big trees and the presence of a dense understory layer are important. Management regimes which apply continuous forest cover might be more appropriate for providing these structural elements simultaneously on small spatial scales, and for the maintenance of a more diverse bird community, thus healthier forest ecosystems.
Authors:P. A. S. Theophilus, M. J. Victoria, K. M. Socarras, K. R. Filush, K. Gupta, D. F. Luecke and E. Sapi
Lyme disease is a tick-borne multisystemic disease caused by Borrelia burgdorferi. Administering antibiotics is the primary treatment for this disease; however, relapse often occurs when antibiotic treatment is discontinued. The reason for relapse remains unknown, but recent studies suggested the possibilities of the presence of antibiotic resistant Borrelia persister cells and biofilms.
In this study, we evaluated the effectiveness of whole leaf Stevia extract against B. burgdorferi spirochetes, persisters, and biofilm forms in vitro. The susceptibility of the different forms was evaluated by various quantitative techniques in addition to different microscopy methods. The effectiveness of Stevia was compared to doxycycline, cefoperazone, daptomycin, and their combinations. Our results demonstrated that Stevia had significant effect in eliminating B. burgdorferi spirochetes and persisters. Subculture experiments with Stevia and antibiotics treated cells were established for 7 and 14 days yielding, no and 10% viable cells, respectively compared to the above-mentioned antibiotics and antibiotic combination. When Stevia and the three antibiotics were tested against attached biofilms, Stevia significantly reduced B. burgdorferi forms. Results from this study suggest that a natural product such as Stevia leaf extract could be considered as an effective agent against B. burgdorferi.
Authors:J. L. Zhao, L. Zou, L. Y. Zhong, L. X. Peng, P. L. Ying, M. L. Tan and G. Zhao
This study was to examine the effects of four fungal polysaccharides, namely exo-polysaccharide (EPS), water-extracted mycelia polysaccharide (WPS), sodium hydroxideextracted mycelia polysaccharide (SPS), and hydrochloric-extracted mycelia polysaccharide (APS) obtained from the endophytic fungus Bionectra pityrodes Fat6, on the sprout growth and flavonoids production of Fagopyrum tataricum. Without obvious changes in the appearance of the sprouts, the exogenous polysaccharide elicitors notably stimulated the sprout growth and functional metabolites accumulation, and the stimulation effect was mainly depended on the polysaccharide species along with its treatment dose. With application of 150 mg/l of EPS, 150 mg/l of WPS and 200 mg/l of SPS, the total rutin and quercetin yield of buckwheat sprouts was effectively increased to 49.18 mg/(100 sprouts), 50.54 mg/(100 sprouts), and 52.27 mg/(100 sprouts), respectively. That was about 1.57- to 1.66-fold in comparison with the control culture of 31.40 mg/(100 sprouts). Moreover, the present study revealed the accumulation of bioactive flavonoids resulted from the stimulation of the phenylpropanoid pathway by fungal polysaccharide treatments. It could be an efficient strategy for improving the nutritional and functional quality of tartary buckwheat sprouts applied with specific fungal elicitors.
Authors:S. A. Colecchia, P. De Vita and M. Rinaldi
A 2-year conservation agriculture experiment was conducted in Southern Italy on durum wheat continuous cropping. Aim of the research was to assess the durum wheat productivity and grain quality in reduced soil tillage systems, according to conservation agriculture principles. The interactions among experimental treatments and climate revealed a close relationship among grain yield, grain quality and wheat growth conditions. Specifically, conventional tillage (CT, plowing and 2 disc harrowing) showed in the 2-year period higher grain production than reduced tillage treatments, minimum (MT, 1 disc harrowing) and No tillage (NT), especially for good crop water availability (3.29 t ha–1 of grain yield in CT, 2.67 in MT and 2.54 in NT). The amount of rainfall (above the average in both years) and its distribution in the growing seasons (more regular in the first year) strongly influenced wheat-grain quality indices (11.97% of protein content in the first year and 9.82% in the second one). Also, the wheat quality resulted more sensitive to the “Year × Tillage” interaction, with differences among tillages more evident in the second year and favourable to NT and MT. Spectral vegetation indexes (NDVI and TVI) measurements at flowering, have been shown to be useful to support farmers in N-late application for improving grain wheat quality. From this experiment carried out during the conversion period and in wet years, wheat managed with CT resulted in higher grain yield and quality, while only test weight showed a significant “Year × Tillage” interaction. Further indications emerged on the need to supply additional (10–20%) seed amount at sowing and crop nitrogen fertilizer in the first transition years in reduced tillage systems compared to conventional ones.
Authors:N. Pržulj, M. Mirosavljević, P. Čanak, M. Zorić and J. Boćanski
Unpredictable environmental conditions lead to occurrence of large genotype by environment (G × E) interaction. It reduces the correlation between genotypic and phenotypic values and complicates selection of superior genotypes. The objective of this study was to estimate genotype by year (G × Y) interaction using AMMI model, to identify spring barley genotypes with stable and high yield performance and to observe association of different meteorological variables with tested growing seasons. The trials with 15 spring barley genotypes were conducted during seven years (1999–2005) at the location of Rimski Šančevi. The results showed that the influence of year (Y), genotype (G) and G × Y interaction on barley grain yield were significant (p < 0.01). Meteorological variables varied significantly from year to year and Y explained the highest percent of treatment variation (81%). The first three IPCA were significant and explained 83% of interaction variation. According to this study, it could be concluded that AMMI analysis provided an enhanced understanding of G × Y interaction in barley multi-years trials. Among the tested genotypes, LAV and NS 477 could be separated as highest yielding genotypes, however LAV could be recommended for further breeding program and large-scale production due to its stable and high yielding performance. It also provided better insight in specific association between spring barley grain yield and meteorological variables.
Authors:N. Yu, R. Laurenz, L. Siler, P. K. W. Ng, E. Souza and J. M. Lewis
White wheat is, categorically, more susceptible to pre-harvest sprouting (PHS) than red wheat. Physiological maturity (PM), defined as when the seeds reach their maximum dry weight, is a critical time before harvesting. The objective of this study was to determine a reference level of α-amylase activity and the corresponding Falling Number (FN) value near the time of PM of selected red and white cultivars in the absence of PHS inducing conditions. Twenty-four soft winter wheat genotypes (12 red and 12 white) adapted to Michigan with varying historic levels of susceptibility to PHS were planted in an α-lattice design in two locations from 2008 to 2010. Spikes were collected three days before PM, at PM, and three days post PM. Samples were freeze-dried, threshed, milled and evaluated for α-amylase activity and FN value using high throughput method. Within genotype, clear trends were observed in the reduction of α-amylase activity and the increase of FN value during the physiological maturation. A nonlinear relationship between α-amylase activity and FN value was fit with an r2 of 0.801. Significant differences were observed for genotype for both α-amylase activity and FN value for all collection time points. No significant differences were found between red and white wheat, categorically, at any of the three time-points in the absence of PHS. The evaluation results provide a critical reference prior to induction of PHS. The α-amylase activity and FN tests show different advantages in analyzing PHS samples as the relationship between α-amylase activity and FN value is not linear over wide-ranging results.
Authors:Agata Dukaczewska, Roberto Tedesco and Oliver Liesenfeld
Ocular toxoplasmosis is a vision-threatening disease and the major cause of posterior uveitis worldwide. In spite of the continuing global burden of ocular toxoplasmosis, many critical aspects of disease including the therapeutic approach to ocular toxoplasmosis are still under debate. To assist in addressing many aspects of the disease, numerous experimental models of ocular toxoplasmosis have been established. In this article, we present an overview on in vitro, ex vivo, and in vivo models of ocular toxoplasmosis available to date.
Experimental studies on ocular toxoplasmosis have recently focused on mice. However, the majority of murine models established so far are based on intraperitoneal and intraocular infection with Toxoplasma gondii. We therefore also present results obtained in an in vivo model using peroral infection of C57BL/6 and NMRI mice that reflects the natural route of infection and mimics the disease course in humans. While advances have been made in ex vivo model systems or larger animals to investigate specific aspects of ocular toxoplasmosis, laboratory mice continue to be the experimental model of choice for the investigation of ocular toxoplasmosis.
Authors:Dóra Rédei, Norbert Kúsz, Máté Szabó, Gyula Pinke, István Zupkó and Judit Hohmann
The present work is the first phytochemical investigation of Euphorbia davidii Subils. After multistep separation process, three flavonoid glycosides were obtained from the ethyl acetate soluble fraction of the methanol extract of the whole plant. The structures of the isolated compounds were determined as kaempferol 3-O-rhamnoside, myricetin 3-O-rhamnoside, and quercetin 3-O-rhamnoside. Aqueous and organic extracts of the plant were screened in vitro for antiproliferative activity against HeLa (cervix epithelial adenocarcinoma), A431 (skin epidermoid carcinoma), A2780 (ovarian carcinoma) and MCF7 (breast epithelial adenocarcinoma) cells, using the MTT assay. n-Hexane and chloroform extracts demonstrated moderately dose-dependent cell growth inhibitory activity against all four cell lines.
Calculating a sample unit × trait matrix provides a flexible first step in analyzing the relationships between species traits and explanatory variables. This matrix is obtained by multiplying a sample unit × species matrix by a species × trait matrix, but the content of the resulting matrix depends on whether and how traits are standardized and whether or not the multiplication is followed by a weighted averaging step. To maximize versatility of the SU × trait matrix, including comparability among traits, and usability with a wide range of distance measures, we recommend first standardizing traits by min-to-max, then calculating abundance-weighted trait averages in each sample unit.
Authors:V. Muthusamy, F. Hossain, N. Thirunavukkarasu, S. Saha, P. K. Agrawal, S. K. Guleria and H. S. Gupta
Carotenoids play vital role in growth and development of human beings. Yellow maize kernel contains carotenoids that possess provitamin A and antioxidant activity. Multilocation based analyses of 105 maize inbreds of indigenous and exotic origin revealed wide genetic variation for lutein (0.2–11.3 μg/g), zeaxanthin (0.2–20.0 μg/g) and β-carotene (0.0–15.0 μg/g). For β-cryptoxanthin, low variation (0.1–3.3 μg/g) was observed. Carotenoids were quite stable over environments that played minor role in causing variation. The heritability (>90%) and genetic advance (>75%) were high for all the carotenoid components. Zeaxanthin showed positive correlation with lutein and β-cryptoxanthin, while β-carotene, the major provitamin A carotenoid, did not show correlation with other carotenoids. Kernel colour was positively correlated with lutein (0.25), zeaxanthin (0.47) and β-cryptoxanthin (0.44), but not with β-carotene (0.04). This suggested that visual selection based on kernel colour will be misleading in selecting provitamin A-rich genotypes. Inbreds with provitamin A and non-provitamin A carotenoids identified in the present study will help in development of biofortified maize hybrids.
Authors:Bettina Eck-Varanka, Nóra Kováts, Katalin Hubai, Gábor Paulovits, Árpád Ferincz and Eszter Horváth
A wide range of aquatic plants have been proven to release allelochemicals, of them phenolics and tannin are considered rather widely distributed. Tannins, however, have been demonstrated to have genotoxic capacity. In our study genotoxic potential of Lythrum salicaria L. (Purple Loosestrife, family Lythraceae) was assessed by the mussel micronucleus test, using Unio pictorum. In parallel, total and hydrolysable tannin contents were determined. Results clearly show that the extract had a high hydrolysable tannin content and significant mutagenic effect. As L. salicaria has been long used in traditional medicine for chronic diarrhoea, dysentery, leucorrhoea and blood-spitting, genotoxic potential of the plant should be evaluated not only with regard to potential effects in the aquatic ecosystem, but also assessing its safe use as a medicinal herb.
The behavioral basis for habitat selection has been intensively studied, but comparatively little attention has been paid to how the resultant species assemblages are formed or affected. Further, how habitat quality interacts with behavior during habitat selection needs greater exploration. We sought to identify some of the behavioral interactions influencing the development of bird assemblages in agricultural habitats, which we consider a structurally simple model system. We performed point counts in non-cultivated meadows, intensive agriculture, and non-intensive agriculture areas in the 2011 and 2012 breeding seasons in which we particularly focussed on Bobolink (Dolichonyx oryzivorus), Eastern Meadowlark (Sturnella magna), Field Sparrow (Spizella pusilla), Grasshopper Sparrow (Ammodramus savannarum), Savannah Sparrow (Passerculus sandwichensis), and Vesper Sparrow (Pooecetus gramineus). Using presence-absence matrices and EcoSim software on 2011 census data, we determined where competition was likely to occur, and which species were competing. In 2012, we experimentally tested these relationships by introducing artificial competitors onto sites. We implemented a before-after control-impact study by comparing presence-absence data from 2011 to 2012 and using multinomial logistic regression. We found grassland bird assemblages are structured by interspecific competition or attraction. The experimental introduction of Grasshopper Sparrows resulted in several presence/absence changes, which differed based on habitat quality, by conspecifics and four heterospecifics (especially Bobolinks). We speculate that the response to competitors is actually determined by the relative quality of each habitat type for each species.
Authors:Cosme Alvarado-Esquivel, Luis Francisco Sánchez-Anguiano, Jesús Hernández-Tinoco, Emilio Arreola-Cháidez, Juan López, Karla Itzel Salcido-Meraz, Sergio Estrada-Martínez, José Antonio Navarrete-Flores, Alma Rosa Pérez-Álamos, Marcia Hernández-Ochoa, Elizabeth Rábago-Sánchez and Oliver Liesenfeld
Through an age- and sex-matched case-control study, we sought to determine whether female sex workers have an increased risk of Toxoplasma gondii exposure and to determine the sociodemographic, work, clinical, and behavioral characteristics of these workers associated with T. gondii exposure. Female workers (n = 136) and controls (n = 272) were examined with enzyme-linked immunoassays (EIA) for the presence of anti-Toxoplasma IgG and IgM antibodies. IgM positive sera were additionally tested with enzyme linked-fluorescence immunoassay (ELFA). Anti-T. gondii IgG antibodies were found in 21 (15.44%) of 136 cases and in 10 (3.67%) of 272 controls (OR = 4.05; 95% CI: 1.84–8.89; P = 0.0001). Anti-T. gondii IgG levels higher than 150 IU/ml were found in 13 (9.6%) of 136 cases and in 8 (2.9%) of 272 controls (P = 0.007). Anti-T. gondii IgM antibodies were found in two cases and in six controls by EIA, but all were negative by ELFA. T. gondii seropositivity was associated with being born out of Durango State (OR = 10.47; 95% CI: 2.9–36.8; P < 0.01), injuries during sex work (OR = 6.30; 95% CI: 1.1–33.7; P = 0.03), and soil contact (OR = 4.11; 95% CI: 1.2–14.0; P = 0.02). This is the first report of an association of T. gondii infection and female sex workers.
In the present study, we examined the effect of shrub encroachment in temperate semi-natural grasslands on plant species diversity. We tested the hypothesis that an initial shrub encroachment leads to enhanced habitat heterogeneity and thereby to a higher diversity. In a calcareous grassland near Göttingen (Germany) we analysed the effect of shrub encroachment on the species richness in 30, 100 m2 plots each with 10 subplots of 1m2 size. The 30 main plots belonged to six different shrub encroachment classes. A descriptive correlative gradient analysis of shrub invaded grasslands and their species number of flowering plants was performed. Within the 30 plots of different shrub encroachment a total of 203 plant species were recorded. The mean α1-diversity (level of subplots), mean α2-diversity (level of plots) as well as the α3-diversity (level of shrub encroachment classes) have their highest values at medium shrub invaded sites. This finding is in line with our hypothesis of a hump-back relation between shrub encroachment and species richness, and can be explained by the increased habitat heterogeneity. However, Detrended Correspondence Analysis (DCA) emphasized the importance of the present vegetation composition for species richness. The dominance of highly competitive, clonal-growing grass species is accompanied by low diversity swards with a lower facilitation of shrub establishment. Species accumulation curves highlight the benefit of shrub encroachment for γ-(landscape-) diversity. This result emphasises the importance of habitat heterogeneity for biodiversity and, therefore, nature conservation.
Authors:X. J. Li, X. G. Hu, T. Z. Hu, G. Li, Z. G. Ru, L. L. Zhang and Y. M. Lang
Thinopyrum ponticum is particularly a valuable source of genes for wheat improvement. A novel wheat-Th. ponticum addition line, 1–27, was identified using cytology, SSR, ESTSSR, EST-STS and PCR-based landmark unique gene (PLUG) markers in this study. Cytological studies showed that 1–27 contained 44 chromosomes and formed 22 bivalents at meiotic metaphase I. Genomic in situ hybridization (GISH) analysis indicated that two chromosomes from Th. ponticum had been introduced into 1–27 and that these two chromosomes could form a bivalent in wheat background. Such results demonstrated that 1–27 was a disomic addition line with 42 wheat chromosomes and a pair of Th. ponticum chromosomes. One SSR marker (BARC235), one EST-STS marker (MAG3284) and 8 PLUG markers (TNAC1210, TNAC1787, TNAC1803, TNAC1805, TNAC1806, TNAC1821, TNAC1867 and TNAC1957), which were all from wheat chromosome group 7, produced the specific band in Th. ponticum and 1–27, indicating that the introduced Th. ponticum chromosomes belonging to the group 7 of wheat. Sequence analysis on specific bands from Th. ponticum and 1–27 amplified using the PLUG marker TNAC1867 further confirmed this result. The 1–27 addition line was also observed to be high resistant to powdery mildew though it is not clear if the resistance of 1–27 inherited from Th. ponticum. This study provided some useful information for effective exploitation of the source of genetic variability in wheat breeding.
Authors:N. Kumar, Nitin Kumar, A. Shukla, S. C. Shankhdhar and D. Shankhdhar
Global warming is rising as a serious concern affecting agricultural production worldwide. Rice is a staple food crop and the threshold temperature for its pollination is 35 °C. A rise in temperature above this value can cause pollen sterility and may severely affect fertilization. Therefore, a study emphasizing the rise in temperature with respect to pollen viability was conducted with eleven rice genotypes during kharif seasons of 2010 and 2011 in indigenous field conditions. Increasing mean temperature by 12 °C at full flowering was found to severely affect the spikelet attributes of the crop. All genotypes showed spikelet sterility above 90% during both seasons. The study indicated that increased temperature may limit rice yield by affecting spikelet fertility and grain filling. The net reduction in grain yield was 30.4% and 27.6% in 2010 and 2011, respectively. A clear reduction in pollen size under high temperature was shown by scanning electron microscopy.
Authors:Dragana Jakovljević, Sava Vasić, Milan Stanković, Ljiljana Čomić and Marina Topuzović
The antioxidant, antimicrobial activity, total phenolic content and flavonoid concentration of Seseli rigidum Waldst. et Kit. were evaluated. Five different extracts of the aboveground plant parts were obtained by extraction with distilled water, methanol, acetone, ethyl acetate and petroleum ether. Total phenols were determined using the Folin-Ciocalteu’s reagent, with the highest values obtained in the acetone extract (102.13 mg GAE/g). The concentration of flavonoids, determined by using a spectrophotometric method with aluminum chloride and expressed in terms of rutin equivalent, was also highest in the acetone extracts (291.58 mg RUE/g). The antioxidant activity was determined in vitro using DPPH reagent. The greatest antioxidant activity was expressed in the aqueous extract (46.15 μg/ml). In vitro antimicrobial activities were determined using a microdilution analysis method; minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) were determined. Methanolic extract had the greatest influence on bacilli (MIC at 0.0391 mg/ml), but the best antimicrobial effect had acetone and ethyl acetate extracts considering their broad impact on bacteria. According to our research, S. rigidum can be regarded as promising candidate for natural plant source with high value of biological compounds.
Authors:A. Guillaumet, J. Bowman, D. Thornton and D. L. Murray
Previous studies have suggested that the attenuation of Canada lynx (Lynx canadensis) cyclic dynamics with decreasing latitude may be the consequence of a reduced specialization on the lynx’s primary prey, snowshoe hares (Lepus americanus). However, intraguild competitive interactions remain largely unexplored in situations where the temporal dynamics of food resources is pronounced, and lynx populations in the south of their distribution may be negatively affected by interspecific competition with other carnivores. In this paper, we used spectral analysis of fur harvest data collected at the state (US) and province (Canada) level to explore the spatial gradient of cyclic dynamics in lynx. Although some patterns were consistent with the ‘diet specialization’ hypothesis, we found that temporal variance of cycling propensity peaked at mid-latitudes, where transient, non-cyclic periods, coexisted with regular 10-year cycles. In these mid-latitude zones, non-cyclic periods did not coincide with loss of snowshoe hare cycling as demonstrated by historical records, and were not more frequent in recent decades as could be expected under a ‘climatic forcing’ scenario. Instead, we show that non-cyclic periods tended to coincide with periods of high coyote (Canis latrans) abundance and periods when coyotes apparently tracked snowshoe hare abundance as suggested by significant 10-year cycles lagging one or two years behind hare peaks. We used landscape-scale (trapline) fur harvest returns from five provinces in Canada to further probe the importance of interspecific competition in Canada lynx population dynamics. Accounting for coyote distribution and abundance did not bring additional explanatory and predictive power to models based solely on environmental and autecological predictors, suggesting that competition with coyote is not a force driving population abundance and cyclicity among lynx. We discuss the possible factors behind the apparent lack of consistency across spatial scales and recommend that further studies examine species interactions at a smaller (local) scale.
Authors:Zihan Jiang, Keming Ma, M. Anand and Yuxin Zhang
Abiotic and biotic factors have the potential to alter herb communities, however, few studies consider feedback between them. This study explores how variation of species interaction and climatic conditions associated with changes in altitude affect herb community composition. We sampled accumulated temperatures of growth duration (June-November) (ATGD), maximum summer temperatures (MST) and herb community composition (herb height, abundance, richness) on non-gaps and forest-gaps site across an elevational gradient. A significant negative relationship was detected between MST and herb richness. The temperature of non-gaps was cooler than that of forest gaps, and overstory cover positively correlated with herb abundance. However, the ATGD exhibited a negative relationship with overstory cover, in that overstory cover decreased with ATGD. We suggested that temperature has a profound effect on height and richness of herb communities, while the overstory cover is moderating the effect of temperature on herb community structure and influence the abundance of herb community. Conversely, decreases in ATGD weakened the relative importance of overstory cover. We concluded that the interaction of temperature and overstory cover shapes the morphology, abundance and richness of herb communities.
A faunistic survey of leaf beetles (Chrysomelidae) was accomplished in Tehran, Alborz and Qazvin provinces of Iran, during 2012 and 2013. In total, 30 species belong to five subfamilies (Chrysomelinae, Cryptocephalinae, Galerucinae, Cassidinae and Criocerinae) and 22 genera were identified.
Authors:G. Bonanomi, M. Capodilupo, G. Incerti, S. Mazzoleni and F. Scala
The consequences of decline in biodiversity for ecosystem functioning is a major concern in soil ecology. Recent research efforts have been mostly focused on terrestrial plants, while, despite their importance in ecosystems, little is known about soil microbial communities. This work aims at investigating the effects of fungal and bacterial species richness on the dynamics of leaf litter decomposition. Synthetic microbial communities with species richness ranging from 1 to 64 were assembled in laboratory microcosms and used in three factorial experiments of decomposition. Thereafter, the functionality of the different microcosms was determined by measuring their capability to decompose materials with different chemical properties, including two species of litter (Quercus ilex L. and Hedera helix L.), cellulose strips and woody sticks. Incubation was done in microcosms at two temperatures (12°C and 24°C) for 120 days. The number of microbial species inoculated in the microcosms positively affected decomposition rates of Q. ilex and H. helix litters, while relationships found for cellulose and wood were not statistically significant. Diversity effect was greater at higher incubation temperature. We found lower variability of decay rates in microcosms with higher inoculated species richness of microbial communities. Our study pointed out that the relationships between inoculum microbial diversity and litter decomposition is dependent on temperature and litter quality. Therefore, the loss of microbial species may adversely affects ecosystem functionality under specific environmental conditions.
The land mollusc faunas of three forest areas of Tuscany (central Italy) were sampled to test the effect of geographical and environmental factors on the structure of biodiversity. A total of 60 sites were surveyed in the years 2009-2011, recording species richness and abundance of snails in 400 m2 plots randomly selected in beech and oak woods. Sampling strategy relied on a combination of visual search and litter analysis. Environmental variables (topsoil pH and altitude) and UTM coordinates were recorded to detect relationships with species richness and number of individuals per plot. Abundance data were analyzed using non-metric multidimensional scaling and canonical correspondence analysis; faunal similarity within and between areas was computed by the Bray Curtis index and snail assemblages of the two forest types were compared. A total of 55 species were recorded, with low values of local richness and abundance per site compared to other forest sites in central and northern Europe. Total richness was similar in the three areas, but composition and local richness varied significantly between them. Geographical factors explained the highest percentage of variance, while habitat type, altitude and pH only accounted for a minor part. Internal similarity was greater than between-area similarity in two out of three areas. Beech forests had richer and more heterogeneous faunas, but lower levels of abundance than oak woods. The results are discussed in terms of historical biogeography and local environmental conditions, and compared with those from similar surveys across Europe.
Authors:G. Amori, V. Castigliani, O. Locasciulli and L. Luiselli
The role and importance of interspecific competition for rodent communities have been much debated issues, with some early authors suggesting that these are important, and several recent articles suggesting the contrary. In this paper, we studied, for 14 years at a mountainous locality in central Italy, the coexistence dynamics of a two-species system (Apodemus flavicollis, Myodes glareolus) within a 1.44 ha trapping grid, by Capture-Mark-Recapture. Overall, we captured over 1000 rodents during the study period, with annual abundance ranging 2-7 individuals × ha−1. However, the density of the two species varied substantially across years and between sectors of the study plot. Thus, the distributions of the two species on the scale of the study grid were not related to one another. Density of a given species did not affect the percentage of lactating females in either A. flavicollis or M. glareolus. Individual traps differed in their rate of capture such that about 40% of traps were associated more with a particular species. Considering the spatial distribution of traps, we determined that three areas were associated with high probability of capture for only one of the two study species, two of these areas being associated to A. flavicollis and one to M. glareolus. Our analyses suggest that interspecific competition may be present at the local micro-scale, as explained by the fact that in the great majority of the cases in which a given trap was highly successful in capturing one species, it was also very unsuccessful in capturing the other species. However, manipulation experiments are needed to confirm that suggestion.
Authors:M. R. Simón, F. M. Ayala, M. V. Moreno, U. Lohwasser and A. Börner
Tan spot, caused by the fungus Pyrenophora tritici-repentis (Died.) Drechs is an important foliar disease of wheat (Triticum aestivum L.). From a set of phenotypically and molecularly characterized set of Argentinean isolates, two isolates H0019 and H0120 which do not correspond to known races of the pathogen were selected. Segregation for resistance among a set of recombinant inbred lines bred from the cross ‘W7984’ × cv. ‘Opata 85’ was used to identify the basis for resistance at the seedling stage, against those fungal isolates (H0019 and H0120), across three independent environments. On the basis of the mean performance across all three environments, a QTL against chlorosis located on the 6AS and linked to the RFLP locus Xksuh4c was significant for both isolates (with a LOD of 3.76 for isolate H0019 and 5.87 for H0120).
Authors:Khadiga G. Adham, Manal H. Farhood, Maha H. Daghestani, Nadia A. Aleisa, Ahlam A. Alkhalifa, Maha H. El Amin, Promy Virk, Mai A. Al-Obeid and Eman M. H. Al-Humaidhi
One of the common causes of iron overload is excessive iron intake in cases of iron-poor anemia, where iron saccharate complex (ISC) is routinely used to optimize erythropoiesis. However, non-standardized ISC administration could entail the risk of iron overload. To induce iron overload, Wistar rats were intraperitoneally injected with subacute (0.2 mg kg−1) and subchronic (0.1 mg kg−1) overdoses of ISC for 2 and 4 weeks, respectively. Iron status was displayed by an increase in transferrin saturation (up to 332%) and serum and liver iron burden (up to 19.3 μmol L−1 and 13.2 μmol g−1 wet tissue, respectively) together with a drop in total and unsaturated iron binding capacities “TIBC, UIBC” as surrogate markers of transferrin activity. Iron-induced leukocytosis (up to 140%), along with the decline in serum transferrin markers (up to 43%), respectively, mark positive and negative acute phase reactions. Chemical stress was demonstrated by a significant rise (p > 0.05) in indices of the hemogram (erythrocytes, hemoglobin, hematocrit, leukocytes) and stress metabolites [corticosterone (CORT) and lactate]. Yet, potential causes of the unexpected decline in serum activities of ALT, AST and LDH (p > 0.05) might include decreased hepatocellular enzyme production and/or inhibition or reduction of the enzyme activities. The current findings highlight the toxic role of elevated serum and liver iron in initiating erythropoiesis and acute phase reactions, modifying iron status and animal organ function, changing energy metabolism and bringing about accelerated glycolysis and impaired lactate clearance supposedly by decreasing anaerobic threshold and causing premature entering to the anaerobic system.
Authors:Mohamed A. K. Shaddad, Gaber K. Abd El-Baki, Mostafa Doaa and Rafat Al-Shimaa
Two broad bean cultivars (Vicia faba CV Nobaria3 and Vicia faba CV Sakha3) were obtained from Mallwi Agriculture Research Center, El Minia Governorate, Egypt. The seeds were divided into two groups, the first group soaked with distilled water, while the second group were soaked with 3 mM KNO3, respectively, for 4 hours. Seeds were sown and left to grow for 3 weeks then treated with different concentrations of NaCl (0.0, 40, 80, 120 and 160 mM) by top irrigation, then they left to grow further for 65 days from sowing. Plant samples were collected for some measurements: leaf area, plant height, root length, fresh and dry weight, photosynthetic pigments, carotenoids, soluble sugars, soluble proteins, total free amino acids, esterase enzyme, as well as MDA (malondialdehyde) content. Salinity reduced both fresh and dry weight in two broad bean cultivars, this reduction were more pronounced in Sakha3 than Nobaria3. Seed pre-soaking with KNO3 resulted in enhancement of fresh and dry weight production in both cultivars especially at 40 mM NaCl. Photosynthetic pigments were substantially affected by salt treatment while the carotenoids were increased, seed pre-soaking with KNO3 improved these components. The soluble sugars, amino acids as well as soluble proteins showed various responses with increasing salinity in the cultivars, seed pre-soaking with KNO3 has improved these parameters to some extent. The shoots of two cultivars exhibited significant accumulation of MDA, compared to roots exposed to the highest salinity levels. Pre-soaking seeds with KNO3 did not improve MDA in shoots but enhanced it in roots, however, in most cases still lower than the absolute control. The assessment of the esterase isozyme profiles on 7.5% native polyacrylamide gel revealed the presence of 13 isoforms in two faba bean plants in response to KNO3 pre-soaking and treatments with different concentrations of NaCl.
A new species Nenteria lii sp. n. is described on the basis of adults and deutonymphs collected in bamboo (Phyllostachys sp.) leaf litters in Xinxiang (Henan Province, China). The new species is very similar to the species Nenteria japonensis Hiramatsu, 1979, but the apical process of the female genital shield rounded and smooth in the new taxon, but serrate in the previously described Japanese species. A new key to the Eastern-Palearctic Nenteria species is given. A list of the collected bamboo leaf litter associated mites is presented.
Two new species of eriophyoid mite, Aceria bendeguzin. sp., associated with Alcea rosea (Malvaceae) and Acaralox hungarorumn. sp. from Agrimonia eupatoria (Rosaceae), are described and illustrated from Hungary. Morphological differences distinguishing these species from other malvaceous and rosaceous inhabiting congeners are discussed.
Wheat cultivation is of great significance in North-western plains of India and the crop was hitherto considered as almost free from serious insect attack. Recently, Pink stem borer (PSB), Sesamia inferens Walker (Lepidoptera: Noctuidae) has emerged as a new pest and is likely to pose serious threat to the successful cultivation of wheat in the North-western plains of India under largely adopted rice-wheat cropping system. Because of the paucity of data on the developmental biology of PSB on wheat crop regarding this emerging problem of insect damage, studies were initiated on biology of PSB under field as well as screenhouse conditions during seasons of 2010–2011 and 2011–2012. This is the first report on biology of PSB on wheat which indicated that the pest was able to survive well/build up populations on wheat and able to complete its life cycle. It laid eggs either at the base of wheat plant near to soil level or on soil-surface or in the left over stubble of rice plants. Eggs hatched within 7.40±0.08 days and the mean larval duration was 68.52±1.55 days. In the course of development, it passed through 8 larval instars and pupation took place near or within the left over rice stubble. Pupal period was 36.05±0.36 days in male while 37.78±0.17 days in female. The survival of adult moths was 5.31±0.26 days in male while 6.61±0.26 days in female. The mean fecundity was 118.38±11.93 eggs and 89.15 per cent of eggs hatched. The total life cycle took 116.92±2.17 and 119.95±2.05 days in males and females, respectively.
Authors:L. Chen, Y. Tian, S. Chen and O. Liesenfeld
Rapid and accurate diagnosis of influenza is important for patient management and infection control. We determined the performance of the cobas® Influenza A/B assay, a rapid automated nucleic acid assay performed on the cobas® Liat System for qualitative detection of influenza A and influenza B from nasopharyngeal (NP) swab specimens. Retrospective frozen and prospectively collected NP swabs from patients with signs and symptoms of influenza collected in universal transport medium (UTM) were tested at multiple sites including CLIA-waived sites using the cobas® Influenza A/B assay. Results were compared to the Prodesse ProFlu+ assay and to viral culture. Compared to the Prodesse ProFlu+ Assay, sensitivities of the cobas® Influenza A/B assay for influenza A and B were 97.7 and 98.6%, respectively; specificity was 99.2 and 99.4%. Compared to viral culture, the cobas® Influenza A/B assay showed sensitivities of 97.5 and 96.9% for influenza virus A and B, respectively; specificities were 97.9% for both viruses. Polymerase chain reaction (PCR)/sequencing showed that the majority of viral culture negative but cobas® Influenza A/B positive results were true positive results, indicating that the cobas® Influenza A/B assay has higher sensitivity compared to viral culture.
In conclusion, the excellent accuracy, rapid time to result, and remarkable ease of use make the cobas® Influenza A/B nucleic acid assay for use on the cobas® Liat System a highly suitable point-of-care solution for the management of patients with suspected influenza A and B infection.
Authors:M. Belahmar, F. Elkfel, M. Mihoub, S. Abdewahab, M. Mateille and S. Sellami
Surveys were conducted during 2010–2013 in olive growing areas of south and north of Algeria to identify plant parasitic nematodes associated with this crop. Sixteen genera of plant-parasitic nematodes were identified. Among them four are considered as having economic importance for olive. Among these the endoparasites Pratylenchus spp. were detected in the majority of the sampled areas and were the most frequent. Meloidogyne spp. were also present in some areas. Helicotylenchus spp. were present with a high frequency in almost all surveyed sites. Among the ectoparasites, only Xiphinema spp. have potential to damage olive. Other nematodes of less importance were poorly represented. Nematode densities varied according to taxa identified and areas surveyed. Excepted Pratylenchus spp. and Helicotylenchus spp., the others taxa are reported for the first time on olive in Algeria.
Authors:U. Erben, N. N. Pawlowski, M. M. Heimesaat, C. Loddenkemper, K. Doerfel, S. Spieckermann, B. Siegmund and A. A. Kühl
Targeting human CD2 with the monoclonal antibody (mAb) CB.219 reduces intestinal inflammation in a colitis model where T cells carry human CD2. Here, we asked whether this mAb has adverse effects on infection control.
Mice expressing human CD2 on T cells (huCD2tg) were orally infected with Toxoplasma (T.) gondii and treated with the human CD2-specific mAb CB.219 in a preventive setting. The intestinal T. gondii loads in CB.219 treated mice did not differ from the control group. Histologically, huCD2tg mice showed moderate ileal inflammation that did not change with CB.219 treatment. In the ileum, CB.219 treatment reduced the protein levels of interferon-γ, transforming growth factor β and interleukin-6, whereas interleukin- 18 mRNA was slightly increased. The infiltration of neutrophils, macrophages, and T cells into the ileum was unaffected by CB.219 treatment. However, CB.219 treatment decreased the numbers of forkhead box P3+ regulatory T cells (Treg) in ileum and liver of huCD2tg mice. This was confirmed in vitro using human peripheral blood mononuclear cells.
Taken together, targeting CD2+ T cells by the human CD2 mAb CB.219 does not prevent beneficial immune reactions necessary for pathogen control. Further experiments will address gut specificity, underlying mechanisms, and general applicability of CB.219 treatment.
Authors:J. Traba, M. B. Morales, C. P. Carmona and M. Paula Delgado
Niche theory predicts that coexisting species will partition resources to limit the effects of interspecific competition. We examined microhabitat partitioning in six sets of steppe birds associated to agroecosystems in central Spain (female and male Great Bustards Otis tarda, female and male Little Bustards Tetrax tetrax, Red-legged Partridges Alectoris rufa and Eurasian Stone-curlews Burhinus oedicnemus) to estimate realized niche breadth, overlap and segregation. Principal Components Analysis on data from used and random microhabitat locations produced two axes we retained for analysis related with two key factors: cover-visibility and food availability. Non-parametric kernel density functions were calculated for each of the PCA axes and species (or sexes), and niche overlap estimated as the area shared between species’ density functions. Null models were run to evaluate overlap significance. In analyses of microhabitat selection by the six sets of birds, 13 out of 15 pairs had significant resource partitioning and niche segregation, except for the pairs partridge and female Great Bustard and the two sexes of Great Bustard. Eurasian Stone-curlew showed wider trophic niche breadth, although segregated from the other species, probably because of its higher invertebrate requirements. Great and Little Bustards segregated in both niche axes, selecting microhabitat according to their body size. Accessibility to food resources and shelter seems to be similar for partridges and female Great Bustards, overlapping in their selection, which may indicate the existence of segregation in other niche factors (e.g., feeding habits). Great Bustard males showed niche overlap with females. Little Bustard males showed feeding microhabitat selection patterns similar to those of females, although they preferred more open microhabitats to meet their sexual display requirements. The entire assemblage had significantly less overlap than expected by chance, suggesting that differential microhabitat selection and realized niche partitioning may explain coexistence in steppe bird communities. Our results suggest that the maintenance of different microhabitat structure should be a priority in the management of agricultural environments.
The most important viral pathogens of the cultivated potato are Potato virus X (PVX) and Potato virus Y (PVY), which can reduce potato production up to 80%. Thus resistance breeding is one of the major goals of plant breeders. Wild potato species are good sources of resistance (R) genes. The resistant plants respond to viral infection with hypersensitive reaction (HR) or extreme resistance (ER). HR is accompanied by programmed cell death, while ER localizes the virus at the primary infection site and limits virus replication without visible symptoms. While HR is generally strain-specific, ER can act against a broad spectrum of viral pathogens. This review aims to describe the molecular mechanisms of resistance against PVX and PVY in potato.
Authors:Edit Horváth, Krisztina Bela, Csaba Papdi, Ágnes Gallé, László Szabados, Irma Tari and Jolán Csiszár
Arabidopsis thaliana contains 54 soluble glutathione transferases (GSTs, EC 220.127.116.11), which are thought to play major roles in oxidative stress responses, but little is known about the function of individual isoenzymes. The role of AtGST phi 9 (GSTF9) in the salt- and salicylic acid response was investigated using 2-week-old Atgstf9 and wild type (Wt) plants. Atgstf9 mutants accumulated more ascorbic acid (AsA) and glutathione (GSH) and had decreased glutathione peroxidase (GPOX) activity under control conditions. Treatment of 2-week-old seedlings with 10−7 M salicylic acid (SA) for 48 h resulted in elevated H2O2 level and enhanced GST activity in Atgstf9 plants, 10−5 M SA treatment enhanced the malondialdehyde and dehydroascorbate contents compared to Wt. 50 and 150 mM NaCl increased the GST activity, AsA and GSH accumulation in Atgstf9 seedlings more pronounced than in Wt plants. We found that the Atgstf9 mutants had altered redox homeostasis under control and stress conditions, in which elevated AsA and GSH levels and modified GST and GPOX activities may play significant role. The half-cell potential values calculated from the concentration of GSH and GSSG indicate that this GST isoenzyme has an important role in the salt stress response.
Authors:Marie E. Alutis, Ursula Grundmann, André Fischer, Ulrike Hagen, Anja A. Kühl, Ulf B. Göbel, Stefan Bereswill and Markus M. Heimesaat
Matrix metalloproteinases (MMP)-2 and -9 (also referred to gelatinases-A and -B, respectively) are upregulated in the inflamed gut of mice and men. We recently demonstrated that synthetic gelatinase blockage reduced large intestinal pro-inflammatory immune responses and apoptosis following murine Campylobacter (C.) jejuni infection. In order to address which gelatinase mediates C. jejuni-induced immune responses, gnotobiotic MMP-2−/−, MMP-9−/−, and wildtype (WT) mice were generated by broadspectrum antibiotic treatment and perorally infected with C. jejuni strain 81-176. The pathogen stably colonized the murine intestinal tract irrespective of the genotype but did not translocate to extra-intestinal compartments. At days 8 and 14 postinfection (p.i.), less pronounced colonic histopathological changes were observed in infected MMP-2−/− mice, less distinct epithelial apoptosis, but more epithelial proliferation in bo