Anti-Oxidant Activities,Chemical Attributes and Fruit Yield of Peach Cultivars as Influenced by Foliar Application of Ascorbic Acid

Peach fruit is enriched with natural antioxidants but oxidation caused by biotic and abiotic stresses, reduce these antioxidants and consequently effect the quality and yield of the fruit. Therefore, an experiment was conducted to investigate the role of ascorbic acid to sustain the natural antioxidant activity, improve the fruit quality and yield of peach cultivars (Early Grand and Florida King). The peach cultivars, Early Grand and Florida King were tested against four levels of ascorbic acid (200, 400, 600 and 800?ppm) and compared with control as water spray. The foliar application of ascorbic acid significantly influenced anti-oxidant activity and physico-chemical attributes of peach cultivars. However, the foliar application of ascorbic acid @ 800?ppm significantly increased the fruit weight, fruit yield, fruit firmness, total soluble solids, titratable acidity, antioxidant activity of fruit peel, with least percent infected fruits and fruit juice pH as compared to the rest of the treatments. Similarly, significant variation was recorded for peach cultivars regarding anti-oxidant activity and various physico-chemical attributes. The maximum fruit weight, fruit yield, fruit firmness, total soluble solids, titratable acidity and TSS/TA ratio were noted in fruit of cultivar Florida King. On other side the foliar treated fruit of peach cultivar Early Grand had the highest percent infected fruits, fruit juice pH and antioxidant activity of fruit peel. It is concluded from the significant findings of present research that the peach cultivar Florida King performed better in terms of maximum fruit yield, whereas the cultivar Early Grand produced better quality fruits with high anti-oxidant activity when treated with 800?ppm of ascorbic acid as foliar spray.     

Assessment of Heavy Metal Pollution in the Sediments of the River Pra and Its Tributaries

An investigative study was conducted to determine the heavy metal pollution in the sediment in the Pra Basin of Ghana from 27 sampling points during the dry and wet seasons using the geo-accumulation index (Igeo), enrichment factor (EF), and pollution load index (PLI). Sediments were acid digested and analyzed for the following selected metals: arsenic (As), lead (Pb), cadmium (Cd), zinc (Zn), manganese (Mn), total chromium (Cr), nickel (Ni), and iron (Fe) using the dual atomizer and hydride generator atomic absorption spectrophotometer (model ASC-7000 No A309654, Shimadzu, Japan). The metal concentrations (mg kg^?1) in the sediments were as follows: As (0.175)?<?Cd (3.206)?<?Ni (79.927)?<?Zn (118.323)?<?Cr (216.708)?<?Mn (234.742)?<?Pb (335.381)?<?Fe (1354.513) in the dry season and As (0.002)?<?Cd (7.279)?<?Ni (72.663)?<?Zn (35.622)?<?Pb (135.863)?<?Cr (167.604)?<?Mn (183.904)?<?Fe (1138.551) for the wet season. The EF which is an indication of whether metal concentrations are due to anthropogenic activities shows enrichment at all site for the metals Cr, Pb, and Cd in the wet seasons. However, only 4 out of the 27 sites showed Ni enrichment in the wet season. Contrary to the wet season, only Pb and Cr recorded enrichment at all sites during the dry season. Fifteen out of the 27 sites recorded Cd enrichment and 24 out of the 27 sites recorded Ni enriched during the dry season. None of the sites were enriched with Fe, As, Zn, and Mn in either the dry or wet seasons. For both dry and wet seasons, the pollution load index for all the sites except one was at the background levels which is a sign of non-deterioration of the sites studied. In the wet season, the calculated Igeo reveals that the study area is not contaminated with respect to As, Zn, Fe, and Mn; uncontaminated to moderately contaminated with Cd; moderately contaminated with Cr; uncontaminated to moderately to heavily contaminated with Ni; and moderately to heavily contaminated with Pb. The dry season Igeo results reveal non-contamination of the study area with respect to As, Fe, and Mn; uncontaminated to moderately contaminated with Zn; moderately contaminated with Cr; uncontaminated to heavily contaminated with Cd; uncontaminated to extremely contaminated with Ni; and moderately to extremely contaminated with Pb. The high levels of Cd, Pb, and Cr in all the sites are due to unregulated illegal mining activities occurring in and around the study area. It is hoped that this study will prompt the basin management board to improve their management strategies in controlling unregulated illegal mining in the basin sediments.     

High levels of genetic differentiation between Wolbachia-infected and non-infected populations of Folsomia candida (Collembola, Isotomidae)

The Gram-negative -Proteobacterium Wolbachia pipientis has been described as an obligate endosymbiont in many arthropod species, where it induces a variety of reproductive alterations, including parthenogenesis. Recently, this microorganism has also been detected in the parthenogenetic collembolan Folsomia candida. Here, we confirm the occurrence of the endosymbiont also in two Italian parthenogenetic populations of F. candida using ultrastructural (electron microscopy) and molecular (PCR screening on two bacterial genes) evidence. The strain isolated in the Italian populations has almost-identical gene sequences compared to that previously isolated in other populations of F. candida. In addition, we discovered a population of Folsomia cf. candida, which showed the presence of both males and females. This population is not infected by Wolbachia. A screening of two mitochondrial genes (COI and COII) showed that the bisexual population has high levels of genetic divergence in comparison with the parthenogenetic ones, even suggesting the possibility that it belongs to a different species. Furthermore, the remarkably high levels of genetic divergence between the two parthenogenetic populations suggests a possible influence of Wolbachia on inducing such differentiation, and, in the long term, speciation.     

Characterisation of energy-dependent efflux of imazalil and fenarimol in isolates of Penicillium italicum with a low,medium and high degree of resistance to DMI-fungicides

Differential accumulation of [¹⁴C]imazalil and [¹⁴C]fenarimol by germlings of wild-type and DMI-resistant isolates ofPenicillium italicum was studied at various pH values. At pH 7 and 8 the low-resistant isolate E_300–3 accumulated 22% and 35%, respectively, less imazalil than the wild-type isolate W₅. Imazalil accumulation at pH 5 and 6 was similar. Isolate E_300–3 also accumulated less fenarimol as compared with the wild-type isolate. This difference was much more obvious than for imazalil and was observed at all pH values tested. Differences in accumulation of both imazalil and fenarimol between low (E_300–3), medium (H₁₇) and high resistant (I₃₃) isolates were not observed. These results suggest that decreased accumulation of DMIs is responsible for a low level of resistance only and that additional mechanisms of resistance might operate in isolates with a medium and high degree of resistance. With all isolates fenarimol accumulation was energy-dependent. This was not obvious for imazalil.The wild-type and DMI-resistant isolates had a similar plasma membrane potential as determined with the probe [¹⁴C]tetraphenylphosphonium bromide ([¹⁴C]TPP⁺). Various test compounds, among which ATPase inhibitors, ionophoric antibiotics and calmodulin antagonists, affected the accumulation of [¹⁴C]TPP⁺, [¹⁴C]imazalil and [¹⁴C]fenarimol. No obvious correlation between the effects of the test compounds on accumulation levels of the fungicides and [¹⁴C]TPP⁺ could be observed. These results indicate that the plasma membrane potential does not mediate the efflux of DMI fungicides byP. italicum.     

Genetic diversity and differentiation of sea trout (<Emphasis Type="Italic">Salmo trutta</Emphasis>) populations in Lithuanian rivers assessed by microsatellite DNA variation

The genetic diversity and differentiation of sea trout were studied in three river basins in Lithuania: Akmena-Dane, Bartuva, and Nemunas. A total of 282 individuals were genotyped at eight microsatellite loci. A similar level of genetic diversity was found in all of the populations studied: mean allelic richness ranged from 3.64 to 5.03, and average expected heterozygosity ranged from 0.588 to 0.721. Significant genetic divergence was observed among the different river basins as well as between populations within the drainages. All pairwise F _ST values were highly significant, ranging from 0.027 to 0.197. The analysis of molecular variance showed rather weak hierarchical population structuring within the Nemunas basin, which may be explained by extensive gene flow among different river basins or, alternatively, reflect the influence of artificial breeding. Information on genetic diversity and differentiation of the Lithuanian sea trout populations will be useful for future management decisions.     

Optimisation of larval culture of the mussel <Emphasis Type="Italic">Mytilus</Emphasis><Emphasis Type="Italic">edulis</Emphasis> (L.)

The blue mussel Mytilus edulis is a commercially important species whose fishery and culture generally relies on natural spat collection. Hatchery-production could provide an alternative source of seed, enabling reliable expansion of the industry. Mussel spawning and larval rearing trials were carried out to optimise elements of hatchery production. Culturing fertilised eggs at low density (20–200 eggs cm⁻²) rather than high density (400–720 eggs cm⁻²) significantly improved the quality of first veliger larvae and differences in this improvement were evident between the eggs from different females (maternal effects). Veliger larval growth at 17 or 21°C was significantly faster than growth at 14°C. Feeding veliger larvae an identical total ration either daily or at 2–3 day intervals did not significantly affect their growth. Different microalgal diets (1: Isochrysis sp. (clone T-ISO), 2: Chaetoceros calcitrans forma pumilus, 3: C. muelleri, 4: mixed Isochrysis sp. (clone T-ISO) and C. calcitrans f. pumilus, and 5: mixed Isochrysis sp. (clone T-ISO) and C. muelleri) were tested on veliger larval growth and mixed diets outperformed single-species diets.     

Preparation and properties of antibacterial Poly(vinyl alcohol) nanofibers by nanoparticles

Poly(vinyl alcohol) (PVA)/Ag-zeolite nanofiber webs were prepared with different concentrations of Ag-zeolite nanoparticles by the electrospinning technique. Scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), transmission electron microscopy (TEM), Fourier transform-infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Instron, and antibacterial activities analysis were utilized to characterize the morphology and properties of the PVA/Ag-zeolite nanofiber webs. The study results showed that the polymer concentration, applied voltages and tip-to-collector distances were the main factors influencing the morphology of the electrospun nanofiber webs. The introduction of Ag-zeolite nanoparticles improved the mechanical properties and thermal stability of the PVA nanofiber webs. TEM data demonstrated that the Ag-zeolite nanoparticles were well distributed within the nanofiber. FTIR revealed a possible interaction between the PVA matrix and the Ag-zeolite nanoparticles. These fibers showed an antibacterial efficacy of 99.8 % and over against Staphylococcus aureus and Klebsiella pneumoniae at Ag-zeolite concentrations of 1 % and over, because of the presence of the silver nanoparticles in the zeolite.     

Isolation and characterization of Avenin-like protein type-B from durum wheat

Proteomic techniques were applied for the investigation of “avenin-like protein type-B” in tetraploid wheat. Protein was extracted from endosperm, according to a classical chromatographic procedure and its identity confirmed by liquid chromatography-tandem mass spectrometry analysis. The characterization of avenin-like protein type-B was in good agreement with the gene-derived sequence, with the exception of glutamine as N-terminus. The presence in the glutenin extract and the high number of cysteine residues suggested that avenin-like protein type-B is integrated into gluten polymers via inter-chain disulphide bonds. This raises the question of whether the protein could play a role in determining the functional properties of gluten.