Inactivation of fenitrothion on stored maize at different moisture contents

Biological activity of fenitrothion on stored maize at various moisture contents and at different times after application was measured by biological assay using adults of Tribolium castaneum (Herbst). Inactivation of actual residues over time was then determined after making the necessary allowance for chemical breakdown. At a given moisture content, the inactivation process was substantially completed during the first 6 weeks after application and loss of effectiveness from 6 weeks onwards resulted mainly from chemical breakdown. At a given time after application, residues were less active at higher moisture content (m.c). Differences in activity between moisture contents were apparent within a few hours of application and continued to increase for up to 3 days, with relatively little change thereafter during storage of 24 weeks. Thus after 24 weeks, residues on maize of 18% m.c. had an activity about 20% that of similarly-aged residues at 10% m.c. and 4% that of freshly-applied residues at 10% m.c. These results were in general accord with changes in the proportion of the residue which was collected from the kernels by a surface wash with methanol, this readily-extractable residue presumably representing the insecticide that may be picked up by insects.     

Absence of geographical structure of morphological variation in <Emphasis Type="Italic">Juniperus oxycedrus</Emphasis> L. subsp. <Emphasis Type="Italic">oxycedrus</Emphasis> in the Balkan Peninsula

We examined leaf and mature seed cone variation of Juniperus oxycedrus L. subsp. oxycedrus in 12 natural populations across the species range in the Balkan Peninsula. We measured 10 morphological traits from a minimum of 100 leaves in each of 190 individuals, and two morphological traits from 30–50 seed cones in each of 94 females. High phenotypic variation was found, but no geographical structure or cline across populations was detected for any of the studied traits. Mean values of comparable leaf and cone morphological traits did not differ considerably from values reported elsewhere. Gender dimorphism in leaf morphology was detected, but it was not distributed uniformly throughout the studied area. An ANOVA model with both nested and crossed effects revealed that the largest proportion of the total variation was, as expected, contained within populations, partly as among-tree variation (18–47%, depending on the trait) and partly as within-tree variation (33–77%), which was remarkably high. Gender dimorphism explained only 0–3% of the total variation. Differences among populations (2–23%) were significant for all studied traits except one; however, PCA showed no clear geographical differentiation of the studied populations. This lack of phylogeographical structure may be the consequence of repeatedly occurring colonisation-retreat scenarios and suggests the existence of several small refugial populations scattered over a large part of the Balkan Peninsula in the Pleistocene. Further research including palaeobotanical and molecular genetic studies will be needed to better understand the forces that shaped current variation patterns of J. oxycedrus L. subsp. oxycedrus in the Balkan Peninsula.     

The growth of swine bone marrow cells in the presence of heterologous colony stimulating factor: Characterization of the developing cell population

Conditioned medium prepared from the mouse fibroblast cell line L 929 which is known to produce colony-stimulating factor active on mouse bone marrow cells was also able to stimulate the growth of swine bone marrow cells in a liquid culture system. During the first 4 days of culture mononuclear phagocyte and granulocyte colonies developed. Prolonged cultured cells were classified belonging to the macrophage lineage by morphological and cytochemical criteria. These cells fulfill also functional characteristics for macrophages, like expression of Fc receptors, immune phagocytosis and production of prostaglandins. These bone marrow-derived macrophages could also be activated with LPS and lymphocyte-derived mediators.     

AHL signals induce rubrifacine production in a bruI mutant of Brenneria rubrifaciens

Several members of the bacterial genus Brenneria are pathogenic on different tree species. Cell-free extracts from the bacterial phytopathogens Brenneria rubrifaciens, B. salicis, and B. nigrifluens induced production of the red pigment rubrifacine in the B. rubrifaciens bruI insertional mutant Br-212. Analysis of the bruI locus identified an adjacent open reading frame, designated bruR, with homology to luxR. High-performance liquid chromatography and mass spectrometry analysis of ethyl acetate extracts from wild-type B. rubrifaciens and Escherichia coli expressing the bruI gene identified two acyl homoserine lactone (AHL) peaks, N-(3-oxohexanoyl)-homoserine lactone (3OC6HSL) and N-hexanoyl-homoserine lactone (C6HSL). Addition of synthetic 3OC6HSL and C6HSL at 10 μM to the bruI mutant, strain Br-212, induced rubrifacine production and the ability to elicit a hypersensitive reaction (HR) in tobacco leaves. Synthetic C6HSL was less effective at inducing pigment production than 3OC6HSL at 10 μM. The bruI mutant Br-212 did not produce detectable AHLs, indicating that C6HSL and 3OC6HSL are the major AHLs produced by this species. The AHLs N-heptanoyl-DL-homoserine lactone (C7HSL), N-octanoyl-DL-homoserine lactone (C8HSL), and N-(3-oxooctanoyl)-DL-homoserine lactone (3OC8HSL) also induced pigment production in Br-212 and restored its ability to elicit an HR in tobacco, suggesting that cross-talk with other bacterial species may be possible.     

World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) guidelines for evaluating the efficacy of ectoparasiticides against biting and nuisance flies on ruminants

These guidelines have been prepared to assist in the planning, conduct and interpretation of studies for the assessment of the efficacy of ectoparasiticides (excluding repellents) against the biting and nuisance dipteran flies of ruminants. Information is provided on the selection of animals, dose determination and dose confirmation studies, field studies, record keeping and result interpretation. These guidelines advocate the use of pen facilities for dose determination and dose confirmation studies. These guidelines also are intended to assist investigators on how to conduct specific studies, to provide specific information for registration authorities involved in the decision-making process, to assist in the approval and registration of new ectoparasiticides, and to facilitate the worldwide adoption of standard procedures.     

Tracer Dyes Food Green No. 4 and Food Blue No. 3 in Antibiotic and Chemotherapeutic Preparations for Intramammary Application Iv

Comparison has been made between Food Green No. 4 and Food Blue No. 3 as tracer dyes for indirect detection of the drugs in milk after intramammary application of a number of commonly used preparations containing antibiotics and chemotherapeutic agents.The tracer dyes had no effect on the stability of the preparations containing penicillin, penicillin ester, and sulphonamide (I, II, III, V and VI) ; after six months’ storage at room temperature, 75 to 100 per cent of the drugs could be recovered. The Oxytetracycline content in preparation IV recovered by 70 to 100 per cent after two months. There were great differences in the irritating effect of the various preparations, as determined by the cell counts of the milk, but the addition of tracer dye did not alter this effect. A direct relationship was demonstrated between concentrations of, on the one hand, tracer dye and, on the other hand, penicillin (preparations I, II, and III), Oxytetracycline (preparation IV) and sulphonamide (preparations V and VI) in milk from ten treated cows.In all quarter samples tracer dye could be demonstrated for just as long as the drugs, and often one or two milkings longer. Thus the experiments confirm the great certainty with which triphenylmethane dyes can reveal indirectly the presence of very small residues of antibiotics and sulphonamides in the milk after intramammary infusion.     

Determinants of yield in a non-timber forest product: Copaifera oleoresin in Amazonian extractive reserves

Developing sustainable extractive industries in otherwise intact tropical forest regions requires a sound understanding of the production potential of key resource populations. The oleoresin extracted from Copaifera trees is an economically important non-timber forest product harvested throughout the lowland Amazon basin. We studied oleoresin extraction from four species of Copaifera trees with known harvest histories within two contiguous extractive reserves in western Brazilian Amazonia. We conducted a large-scale experimental harvest of 179 previously unharvested Copaifera trees, in both seasonally flooded (várzea) and adjacent unflooded (terra firme) forests. The likelihood of trees yielding any oleoresin was principally determined by their species identity: C. multijuga was the only species to regularly yield oleoresin (70% of trees). Yield volumes varied both amongst species and forest types: C. multijuga (restricted to terra firme forest) had the highest mean yield of 505 ml, whilst C. guyanensis produced higher volumes of oleoresin in várzea (139 ml) than terra firme (15 ml) forest. Intraspecific differences were driven mainly by tree size. To assess extraction sustainability, we reharvested a sample of C. multijuga trees and compared the oleoresin production of 24 conspecific trees that had been initially harvested one year previously with that of 17 trees initially harvested three years previously. Reharvested trees produced just 35% of the oleoresin volume compared to that when originally drilled, but this response was not affected by the time interval between consecutive harvests. We demonstrate that, within a population of Copaifera, both morphological and environmental factors restrict total productivity; consideration of these factors should inform sustainable management practises. We additionally raise methodological considerations that may improve the comparability of studies.     

The influence of urbanisation on diversity and trait composition of birds

We analysed the effect of the urban matrix, the urban space surrounding distinct habitat patches, on bird communities. In doing so we assessed the impact of urbanisation beyond the effect of habitat loss. We used a set of 54 wasteland sites of early successional stages that were scattered over the entire urban area of Berlin, Germany. Sites were similar to each other in habitat structure but differed in their surroundings, the urban matrix. Thus, our study design allows to investigate associations between birds and the urban matrix. Our measures for urbanisation are human population density and degree of sealing within 50 to 2,000 m buffer zones surrounding each wasteland site. Along the urbanisation gradients we calculated three measures of bird communities: alpha diversity, beta diversity, and trait profile of the entire bird community regarding food, life-history, and behavioural traits. Alpha diversity did not change significantly along the gradients of urbanisation. However, beta diversity increased along the urbanisation gradients with urbanisation at the local scale (50 m) but decreased at the landscape scale (200 and 2,000 m). Fourth-corner analysis of relationships between urbanisation and species traits showed trait shifts: adult survival rate increased with human population density and densities of birds that are more often reported to show innovative behaviour increased with both human population density and degree of sealing. We conclude that the influence of the urban matrix contributes to the homogenisation of the avifauna by filtering certain species traits and promoting others.