Transmission of Megatrypanum Trypanosomes to Cervus dama by Tabanidae1

Four fallow deer, Cervus dama, became infected with Trypanosoma (Megatrypanum) sp. by oral application of triturated guts from tabanids collected in an area with deer but without any cattle; four control calves remained negative. Upon challenge with triturated guts from tabanids from an area with pastured cattle, the four calves became infected with Trypanosoma (M.) theileri. The prepatent period in deer was five days or less. Haematopota spp. and Tabanus spp. were identified as vectors of the deer trypanosomes. It is concluded that the trypanosomes of C. dama belong to a Megatrypanum species that is not identical with T. theileri.     

Physical mapping of three fruit ripening genes：Endopolygalacturonase,ACC oxidase and ACC synthase from apple（Malus x domestica） in an apple rootstock A106（Malus sieboldii

The apple rootstock,A106(Malus sieboldii),had 17 bivalents in pollen mother cells at meiotic metaphase 1,and 17 chromosomes in a haploid pollen cell.Karyotypes were prepared from root-tip cells with 2n=34 chromosomes,Seven out of 82 karyotypes(8.5%) showed one pari of satellites at the end of the short arm of chromosome 3.C-bands were shown on 6 pairs of chromosomes 2,4,6,8,14,and 16 near the telomeric regions of short arms.Probes for three ripening-related genes from Malus x domestica:endopolygalacturonase(EPG,0.6kb),ACC oxidase(1.2kb),and ACC synthase(2kb)were hybridized in situ to metaphase chromosomes of A106.Hybridization sites for the EPG gene were observed on the long arm of chromosome 14 in 15 out of 16 replicate spreads and proximal to the centromere of chromosomes 6 and 11.For the ACC oxidase gene,hylridization sites were observed in the telomeric region of the short arm of chromosomes 5 and 11 in 87% and 81% of 16 spreads respectively,proxiaml to the centromere of chromosome 1 in 81% of the spreads,and on the long arm of chromosome 13 in 50% of the spreads. Physical mapping of three fruit ripening genes in an apple rootstock A106.Twenty five spreads were studied for the ACC synthase gene and hybridization sites were observed in the telomeric region of the short arm of chromosome 12 in 96% of the spreads.chromosomes 9 and 10 in 76% of the spreads,and chromosome 17 in 56% of the spreads.     

The cytokineplast: purified, stable, and functional motile machinery from human blood polymorphonuclear leukocytes

We examined the formation of motile, chemotactically active, anucleate fragments from human blood polymorphonuclear leukocytes (PMN, granulocytes), induced by the brief application of heat. These granule-poor fragments are former protopods (leading fronts, lamellipodia) that become uncoupled from the main body of the cell and leave it, at first with a connecting filament that breaks and seals itself. The usual random orientation of such filaments can be controlled by preorientation of cells in a gradient of the chemotactic peptide, N-formylmethionylleucylphenylalanine (F-Met-Leu-Phe) (2x10(-9) M- 1x10(-8)). Cytochalsin B, 2.5-5 μg/ml, prevents fragment formation; colchicine, 10(-5) M, does not. In scanning electron micrographs, fragments are ruffled and the cell body rounded up and rather smooth. In transmission electron micrographs, fragments contain microfilaments but lack centrioles and microtubules. Like intact cells, both bound and free fragments can respond chemotactically to an erythrocyte destroyed by laser microirradiation (necrotaxis); the free, anucleate fragments may do so repeatedly, even after having been held overnight at ambient temperatures. We propse the name cytokineplast for the result of this self-purification of motile apparatus. The exodus of the motile machinery from the granulocyte requires anchoring of the bulk of the cell to glass and uncoupling, which may involve heat-induced dysfunction of the centrosome. In ultrastructural studies of the centrosomal region after heat, centriolar structure remains intact, but pericentriolar osmiophilic material appears condensed, and microtubules are sparse. These changes are found in all three blood cell types examined: PMN, eosinophil, and monocyte. Of these, the first two make fragments under our conditions; the more sluggish monocyte does not. Uncoupling is further linked to centrosomal dysfunction by the observation that colchicines-treated granulocytes (10(-5)M, to destroy the centrosome’s efferent arm) make fragments after less heat than controls. If motive force and orientation are specified mainly from the organelle-excluding leading front, then endoplasmic streaming in PMN is a catch-up phenomenon, and microtubules do not provide the vector of locomotion but rather stabilize and orient the “baggage” (nucleus, granuloplasm)—i.e., they prevent fishtailing. Moreover, constraints emanating from the centrosome may now be extended to include, maintenance of the motile machinery as an integral part of the cell.     

A laboratory study on the short-term zonal oscillations of the trochid Monodonta turbinata (Born) (Mollusca: Gastropoda)

Zonal oscillations of Monodonta turbinata (Born) were monitored with an actographic device which precluded clustering behaviour. Unfed snails maintained their cyclic pattern of behaviour for up to 8 days under a light-dark cycle which simulated the natural one. Under constant conditions of light or dark, however, the snails ceased migration and occupied a zonal position typical of day and night, respectively. Experiments in diffuse light and with light from below the floor of the experimental tank showed that the downward migration of M. turbinata in the daytime depends on positive geotaxis combined with negative phototaxis whilst the upward migration at night depends on a negative geotaxis. This mechanism is similar to that described in other littoral molluscs. There was no evidence of an endogenous control of rhythmic zonal activity.     

La componente lipidica dell'essudato stigmatico di Citrus limon (L.) Burm

Abstract

The lipidic component of Citrus limon (L.) Burm. stigmatic exudate. Chromatographic methods (Gas Chromatography and Thin Layer Chromatography) were used to investigate the lipids present in the stigmatic secretion of Citrus limon.

12 fatty acids, ranging from C 12 to C 24, were identified; they form 7 classes of different lipids, 3 of them having unsaturated components.     

In vitro evaluation of native entomopathogenic fungi and neem (Azadiractha indica) extracts on Spodoptera frugiperda

The control of Spodoptera frugiperda is based on synthetic insecticides, so some alternatives are the use of entomopathogenic fungi (EF) and neem extract. The objective of the study was to evaluate in vitro effectiveness of native EF and neem extracts on S. frugiperda larvae. Six EF were identified by DNA sequencing of ITS regions from three EF (Fusarium solani, Metarrhizium robertsii, Nigrospora spherica and Penicillium citrinum). They were evaluated in concentrations of 1 × 10⁸ spores/ mL. In addition, a second bioassay was carried out evaluating only F. solani, M. robertsii and N. sphaerica and the addition of vegetable oil. On the other hand, extraction of secondary metabolites from neem seed (Azadirachta indica) was carried out by performing, mass (g) and solvent volume (mL ethanol and water) combinations, which were subjected to microwaves and ultrasound. Subsequently, these extracts were evaluated in concentrations of 3%, 4% and 5%. A survival analysis was performed for each of the bioassays. With respect to the results of the first bioassay, F. solani obtained a probability of survival of 0.476 on the seventh day, while in the second bioassay, M. robertsii obtained 0.488 survival probability. This suggests that the expected percentage of larvae that stay alive on the sixth day is 48.8%. However, in the evaluation of the neem extract the combination 1:12/70% to 4% caused 84% mortality of larvae. The use of native HE and neem extracts has potential for the control of S. frugiperda.     

Pelagic seabird flight patterns are consistent with a reliance on olfactory maps for oceanic navigation

Homing studies have provided tantalizing evidence that the remarkable ability of shearwaters (Procellariiformes) to pinpoint their breeding colony after crossing vast expanses of featureless open ocean can be attributed to their assembling cognitive maps of wind-borne odours but crucially, it has not been tested whether olfactory cues are actually used as a system for navigation. Obtaining statistically important samples of wild birds for use in experimental approaches is, however, impossible because of invasive sensory manipulation. Using an innovative non-invasive approach, we provide strong evidence that shearwaters rely on olfactory cues for oceanic navigation. We tested for compliance with olfactory-cued navigation in the flight patterns of 210 shearwaters of three species (Cory''s shearwaters, Calonectris borealis, North Atlantic Ocean, Scopoli''s shearwaters, C. diomedea Mediterranean Sea, and Cape Verde shearwaters, C. edwardsii, Central Atlantic Ocean) tagged with high-resolution GPS loggers during both incubation and chick rearing. We found that most (69%) birds displayed exponentially truncated scale-free (Lévy-flight like) displacements, which we show are consistent with olfactory-cued navigation in the presence of atmospheric turbulence. Our analysis provides the strongest evidence yet for cognitive odour map navigation in wild birds. Thus, we may reconcile two highly disputed questions in movement ecology, by mechanistically connecting Lévy displacements and olfactory navigation. Our approach can be applied to any species which can be tracked at sufficient spatial resolution, using a GPS logger.     

Mercury-resistant bacterial strains Pseudomonas and Psychrobacter spp. isolated from sediments of Orbetello Lagoon (Italy) and their possible use in bioremediation processes

This study was aimed to isolate Hg-resistant bacteria from contaminated sediments of the Orbetello Lagoon in Italy and to assess their possible use as biofilms in bioremediation processes. Enrichment cultures prepared from contaminated sediments in the presence of 0.05 mM of mercury and under aerobic conditions allowed the isolation of five heterotrophic bacterial strains. 16S rDNA gene sequencing assigned the isolated strains to the genera Pseudomonas and Psychrobacter. For the first time mercury-resistant bacterial strains belonging to the genus Psychrobacter were evidenced. Minimum inhibitory concentrations in the presence of HgCl₂ and of CH₃HgCl showed high levels of resistance. EC50 values for the isolated bacterial strains in the presence of HgCl₂ and of CH₃HgCl confirmed the adaptation to the metal. Hg-resistant strains ORHg1, ORHg4 and ORHg5 showed the capacity to volatilize inorganic and organic mercury to elemental mercury, and formed biofilms on pumice particles, and were shown to play a role in the removal of mercury from sediment leachates. This study reports isolation and characterization of new Hg-resistant bacterial strains and provides novel insight into their possible use in bioremediation processes of mercury polluted sediments.     

Organophosphate-resistant forms of acetylcholinesterases in two scallops--the Antarctic Adamussium colbecki and the Mediterranean Pecten jacobaeus

We describe the acetylcholinesterase polymorphisms of two bivalve molluscs, Adamussium colbecki and Pecten jacobaeus. The research was aimed to point out differences in the expression of pesticide-resistant acetylcholinesterase forms in organisms living in different ecosystems such as the Ross Sea (Antarctica) and the Mediterranean Sea. In A. colbecki, distinct acetylcholinesterase molecular forms were purified and characterized from spontaneously soluble, low-salt-soluble and low-salt-Triton extracts from adductor muscle and gills. They consist of two non-amphiphilic acetylcholinesterases (G(2), G(4)) and an amphiphilic-phosphatidylinositol-membrane-anchored form (G(2)); a further amphiphilic-low-salt-soluble G(2) acetylcholinesterase was found only in adductor muscle. In the corresponding tissues of P. jacobaeus, we found a non-amphiphilic G(4) and an amphiphilic G(2) acetylcholinesterase; amphiphilic-low-salt-soluble acetylcholinesterases (G(2)) are completely lacking. Such results are related with differences in cell membrane lipid compositions. In both scallops, all non-amphiphilic AChEs are resistant to used pesticides. Differently, the adductor muscle amphiphilic forms are resistant to carbamate eserine and organophosphate diisopropylfluorophosphate, but sensitive to organophoshate azamethiphos. In the gills of P. jacobaeus, amphiphilic G(2) forms are sensitive to all three pesticides, while the corresponding forms of A. colbecki are sensitive to eserine and diisopropylfluorophosphate, but resistant to azamethiphos. Results indicate that organophosphate and/or carbamate resistant AChE forms are present in species living in far different and far away environments. The possibility that these AChE forms could have ensued from a common origin and have been spread globally by migration is discussed.     

Nocturnal line transect sampling of wild boar (Sus scrofa) in a Mediterranean forest: long-term comparison with capture–mark–resight population estimates

Although accurate estimates of wild boar (Sus scrofa) populations are crucial for any effective resource management or pest control programme, this species is well-known to be difficult to monitor. We conducted a 10-year study in a fenced Mediterranean forest (Rome, Italy) to evaluate nocturnal line transect sampling performances. We focused on its accuracy in monitoring changes in density, which was independently estimated by capture–mark–resight (CMR) performed on counts at feeding sites. We carried out night surveys in the autumn of 2001–2010, using portable infrared cameras to detect animals. We sampled on foot to cover the whole study area and the different habitat types evenly. However, to ensure safe working conditions during night and to limit disturbance, we placed transects along paths and forest roads. Therefore, we investigated the potential impact of our convenience sampling on the detection process, using radiolocations of wild boars to assess their distribution with respect to selected transects. We found that our survey design should not have biased our estimates and that densities and coefficients of variations from line transect sampling were consistent with CMR results. Although labour-intensive, we believe that our approach can improve wild boar monitoring effectively, even in concealing habitats, providing decision makers with accurate estimates (and quantified confidence limits) which can help to develop the most appropriate management programme. Moreover, the current low price of new-generation infrared cameras can also increase strongly the cost-effectiveness of this method.