Metatranscriptomics and Pyrosequencing Facilitate Discovery of Potential Viral Natural Enemies of the Invasive Caribbean Crazy Ant, Nylanderia pubens

BACKGROUND: Nylanderia pubens (Forel) is an invasive ant species that in recent years has developed into a serious nuisance problem in the Caribbean and United States. A rapidly expanding range, explosive localized population growth, and control difficulties have elevated this ant to pest status. Professional entomologists and the pest control industry in the United States are urgently trying to understand its biology and develop effective control methods. Currently, no known biological-based control agents are available for use in controlling N. pubens. METHODOLOGY AND PRINCIPAL FINDINGS: Metagenomics and pyrosequencing techniques were employed to examine the transcriptome of field-collected N. pubens colonies in an effort to identify virus infections with potential to serve as control agents against this pest ant. Pyrosequencing (454-platform) of a non-normalized N. pubens expression library generated 1,306,177 raw sequence reads comprising 450 Mbp. Assembly resulted in generation of 59,017 non-redundant sequences, including 27,348 contigs and 31,669 singlets. BLAST analysis of these non-redundant sequences identified 51 of potential viral origin. Additional analyses winnowed this list of potential viruses to three that appear to replicate in N. pubens. CONCLUSIONS: Pyrosequencing the transcriptome of field-collected samples of N. pubens has identified at least three sequences that are likely of viral origin and, in which, N. pubens serves as host. In addition, the N. pubens transcriptome provides a genetic resource for the scientific community which is especially important at this early stage of developing a knowledgebase for this new pest

Evaluation of a lateral flow immunoassay for field identification of Solenopsis invicta (Hymenoptera: Formicidae) in Australia

In an effort to improve surveillance capacity for the exotic red imported fire ant, Solenopsis invicta, a lateral flow immunoassay (LFA) was recently evaluated by Biosecurity Queensland staff in Australia. The purpose of the research was to assess the ability of the fire ant LFA to discriminate S. invicta from ants found in Australia and to conduct the first field evaluation of the test. In addition to S. invicta, 36 species of ants, collected mainly from Queensland, were evaluated by the LFA, including species from the Dolichoderinae (n = 7), Formicinae (n = 13), Myrmeciinae (n = 1), Myrmicinae (n = 11), Ponerinae (n = 3) and Pseudomyrmicinae (n = 1) subfamilies. The fire ant LFA test correctly identified S. invicta in every instance. No cross reactivity was observed in the other ant species. Field tests by staff previously unfamiliar with the test resulted in suggestions for improving ant collection and manipulation. The fire ant LFA appears to be suitable for use in Australia for rapid confirmation of potential new detections of S. invicta

Macrodinychus mites as parasitoids of invasive ants: an overlooked parasitic association

International audienc

In situ observation of self-assembled hydrocarbon Fischer–Tropsch products on a cobalt catalyst

Fischer-Tropsch synthesis is a heterogeneous catalytic reaction that creates approximately 2% of the world's fuel. It involves the synthesis of linear hydrocarbon molecules from a gaseous mixture of carbon monoxide and hydrogen at high pressures (from a few to tens of bars) and high temperatures (200-350 €...°C). To gain further insight into the fundamental mechanisms of this industrial process, we have used a purpose-built scanning tunnelling microscope to monitor a cobalt model catalyst under reaction conditions. We show that, after 30 €...minutes of reaction, the terraces of the cobalt catalyst are covered by parallel arrays of stripes. We propose that the stripes are formed by the self-assembly of linear hydrocarbon product molecules. Surprisingly, the width of the stripes corresponds to molecules that are 14 or 15 carbon atoms long. We introduce a simple model that explains the accumulation of such long molecules by describing their monomer-by-monomer synthesis and explicitly accounting for their thermal desorption