Evaluation of chlorfenapyr for control of the bed bug,Cimex lectularius L.

BACKGROUND: The presence of bed bug populations resistant to pyrethroids demands the development of new control tactics, including the use of insecticides with new modes of action. Insecticides that disrupt oxidative phosphorylation in insect mitochondria can be an option. Laboratory assays were used to measure the toxicity of chlorfenapyr to susceptible strains and two strains highly resistant to pyrethroids. The effectiveness of two chlorfenapyr‐based formulations was compared, and behavioral responses of bed bugs to dry residues of aerosol sprays were evaluated. RESULTS: Chlorfenapyr was effective against all bed bug strains, killing them at a similar rate, regardless of their susceptibility status to pyrethroids. Dry residues aged for 4 months were as toxic as fresh dry residues. The aerosol formulation had contact activity and caused faster mortality than a water‐based formulation. Bed bugs did not avoid resting on surfaces treated with aerosol. CONCLUSION: Chlorfenapyr is an option for controlling pyrethroid‐resistant bed bugs. While it does not cause quick knockdown, its long residual activity and no avoidance behavior of bed bugs to dry residues appear to make this insecticide suitable for bed bug control. A faster insecticidal effect is obtained with the aerosol formulation, suggesting greater bioavailablity of the toxicant. Copyright © 2010 Society of Chemical Industry     

All three classes of CpG ODNs up-regulate IP-10 gene in pigs

The analysis of CpG ODN induced innate immune responses in different animal species has shown substantial similarities and differences in levels and types of induced cytokines profile. The objectives of these studies were to identify innate immune biomarkers activated by three classes of CpG ODNs in pigs. For this purpose, we investigated the kinetics of innate immune responses in immune cells from pigs following in vitro and in vivo stimulation with CpG ODNs. The mRNA expression of cytokine and chemokine genes were assayed by SYBR^@ green based quantitative real time PCR. A-class CpG ODN induced significant but transient levels of IFN-γ, IL-12 (P40), IL-6, IL-4 and TNF-α mRNA, C-class CpG ODN induced significant level of IFN-γ, IFN-α and IL-12 mRNA and the lowest level of IL-4 (Th-2 type) mRNA. A very low level of some cytokines stimulation was observed by GC ODNs. It is noteworthy, that IL-12 (P35) mRNA was significantly stimulated by B-class GpC ODN 7909. Interestingly, all classes of CpG ODNs induced significant level of IP-10 at 12 h post stimulation. These in vitro and in vivo observations suggest that interferon-γ inducible protein 10 (IP-10) may be a reliable biomarker for immune activity induced by CpG ODNs in pigs.     

Metabolism of Sucrose in Apples I.

The volatile oil contents of dried leaves of Majorana hortensis, Melissa officinalis, Ocimum basilicum, Origanum vulgare, Salvia officinalis and Thymus vulgaris reached maximum values in summer. Different harvest dates are required in order to obtain the highest yields of dried leaves ha^-1, the highest levels of volatile oil in the dried leaves, and the highest yields of volatile oil ha^-1. The upper parts of balm, oregano and sage plants yielded the most dried leaves, but the lower parts showed the highest levels of volatile oil in the dried leaves.     

Identification of novel Cryptosporidium genotypes in kangaroos from Western Australia

A total of 763 faecal samples were collected from western grey kangaroos (Macropus fuliginosus) in Western Australia and screened for the presence of Cryptosporidium by PCR at the 18S ribosomal RNA (rRNA) locus. Samples that were positive at the 18S locus were also amplified at the actin locus. The overall prevalence was 9.3% (71/763). At the 18S rRNA locus, sequences were obtained for 28 of the 71 positives. Sequence analysis identified four species; Cryptosporidium fayeri in seven isolates, Cryptosporidium marcopodum in four isolates, Cryptosporidium xiaoi in six isolates and a novel genotype (kangaroo genotype I) in eleven isolates. Analysis at the actin locus confirmed the genetic distinctness of the novel genotype. The results of the present study indicate that in addition to C. fayeri and C. marcopodum, kangaroos may be capable of being infected with a wider range of Cryptosporidium species and genotypes including livestock species such as C. xiaoi. The novel genotype identified in the kangaroos most likely represents a cryptic species that requires further analyses to confirm its species status.     

Immunization of chickens with Salmonella enterica subspecies enterica serovar Enteritidis pathogenicity island-2 proteins

Several structural components of the type III secretion systems (T3SS) encoded by Salmonella pathogenicity island (SPI)-1 and SPI-2 are exposed to the host's immune system prior to/during the infection/invasion process, making them potential vaccine candidates. In this study we evaluated whether chickens vaccinated with SPI-2 T3SS components could mount a significant humoral immune response (as measured by serum IgG titres) and whether these antibodies could be transferred to progeny (as measured by egg yolk IgG titres), and whether vaccinates and progeny of vaccinates could be protected against challenge with SE. The results of our studies show that vaccinated chickens do produce high levels of SPI-2 T3SS specific serum IgG that they are able to transfer to their progeny. It was demonstrated that vaccinates and progeny of vaccinates had lower overall countable recovered Salmonella enterica subspecies enterica serovar Enteritidis (SE) per bird in most situations.     

Riverine Flux of Metals from Historically Mined Orefields in England and Wales

Water, Air, &; Soil Pollution - The flux of metals at the tidal limits of major rivers are an important metric of freshwater contaminant transfer to marine habitats, reported in Northeast...     

Air pollution injury of potato in Michigan

A disorder of Michigan potatoes tentatively called speckle leaf is associated, in part, with air pollution injury. The disease is characterized by reduced yields following early vine maturity, premature vine death, and yellowing of the lower leaves. Necrotic spots developed on the upper surface of leaves, followed by bronzing, and upward leaf rolling. Severely affected leaves became chlorotic and remained attached to the stem. Potato plants were grown in two plastic houses through which was blown either ambient field air or ambient air filtered through activated charcoal. Plants grown in the plastic house receiving ambient air developed symptoms similar to nearby field plants. Plants grew normally in filtered ambient air and remained free of speckle leaf and air pollution injury symptoms. The potato varieties Haig, Norchip, and Superior were most sensitive, Sebago was intermediate, and Kennebec and Katahdin were most tolerant. Tobacco plants in ambient non-filtered air developed symptoms typical of ozone injury. Bean leaves became bronzed with brown necrotic flecks on both surfaces, and severely affected leaves dropped. Neither tobacco nor bean was affected in the filtered air.     

Summer cover crop impacts on soil percolation and nitrogen leaching from a winter corn field

The impacts of a leguminous summer cover crop (sunn hemp; Crotalaria juncea) on nitrogen leaching from a corn (Zea mays L.) field was evaluated by direct measurements of soil water content and nitrogen balance components, complemented by direct and inverse modeling as an exploratory tool to better understand water flow and nitrogen balances in the soil. Water and nitrogen inputs and outputs were measured during winter corn production in an experimental field located in the south Miami-Dade basin in southern Florida (USA). Data from the last two seasons (2001-2002 and 2002-2003) of a 4-year study are presented. The field was divided into six 0.13 ha plots. One-half of the plots were rotated with sunn hemp (CC plots) during the summer while the remaining plots were kept fallow (NC plots). Sweet corn management was uniform on all plots and followed grower recommended practices. A numerical model (WAVE) for describing water and agrochemical movement in the soil was used to simulate water and nitrogen balances in both types of plots during the corn seasons. The hydrodynamic component of WAVE was calibrated with soil water data collected continuously at three depths, which resulted in accurate soil water content predictions (coefficients of efficiency of 0.85 and 0.91 for CC and NC plots, respectively). Measured components of the nitrogen balance (corn yields, estimated nitrogen uptake, and soil organic nitrogen) were used to positively assess the quality of the nitrogen simulation results. Results of the modeled water balance indicate that using sunn hemp as a cover crop improved the soil physical conditions (increase in soil water retention) and subsequently enhanced actual crop evapotranspiration and reduced soil drainage. However, nitrogen simulation results suggest that, although corn nitrogen uptake and yields were slightly higher in the CC plots than in the NC plots, there were net increases of soil N content that resulted in increased N leaching to the shallow aquifer. Therefore, the use of sunn hemp as cover crop should be coupled with reductions in N fertilizer applied to the winter crop to account for the net increase in soil N content.