What works in conservation? Using expert assessment of summarised evidence to identify practices that enhance natural pest control in agriculture

This paper documents an exercise to synthesize and assess the best available scientific knowledge on the effectiveness of different farm practices at enhancing natural pest regulation in agriculture. It demonstrates a novel combination of three approaches to evidence synthesis—systematic literature search, collated synopsis and evidence assessment using an expert panel. These approaches follow a logical sequence moving from a large volume of disparate evidence to a simple, easily understandable answer for use in policy or practice. The example of natural pest regulation in agriculture was selected as a case study within two independent science-policy interface projects, one European and one British. A third funder, a private business, supported the final stage to translate the synthesized findings into a useful, simplified output for agronomists. As a whole, the case study showcases how a network of scientific knowledge holders and knowledge users can work together to improve the use of science in policy and practice. The process identified five practices with good evidence of a benefit to natural pest regulation, with the most beneficial being ‘Combine trap and repellent crops in a push–pull system’. It highlights knowledge gaps, or potential research priorities, by showing practices considered important by stakeholders for which there is not enough evidence to make an assessment of effects on natural pest regulation, including ‘Alter the timing of pesticide application.’ Finally, the process identifies several important practices where the volume of evidence of effects on natural pest regulation was too large (>300 experimental studies) to be summarised with the resources available, and for which focused systematic reviews may be the best approach. These very well studied practices include ‘Reduce tillage’ and ‘Plant more than one crop per field’.     

Release of arachidonic acid from human endometrial cells in culture mediated by calcium ionophore (A23187) or fluoride.

Primary cultures of endometrial glands and stromal cells were labelled with [14C]-arachidonic acid for 4 h before exposure to either the calcium ionophore, A23187 (which activates phospholipase A2 (PLA2) by increasing intracellular calcium concentrations) or sodium fluoride (which activates a G-protein). Calcium ionophore (0.5-50 mumol/l) stimulated a dose- and time-dependent release of arachidonic acid from endometrial glands. Incubation with ionophore (10 mumol/l) for 1 h released 22% of the incorporated arachidonic acid. There was a corresponding decrease in phospholipids and no loss from triglycerides. Stromal cells were unresponsive to ionophore. Fluoride (10 mmol/l) stimulated a release of arachidonic acid from stromal cells and endometrial glands (6.5% of the total arachidonic acid incorporated). In stromal cells, arachidonic acid was released from triglycerides in Day-1 cultures and from phospholipids in Day-2 cultures. In both Day-1 and Day-2 cultures of endometrial glands, arachidonic acid was released from phospholipids, but not from triglycerides. Among the phospholipids, phosphatidylcholine was always the major source of arachidonic acid. Arachidonic acid release from endometrial glands and stromal cells may be mediated by activation of PLA2 (or phospholipase C) via a G-protein, but in glands calcium ionophore may have a direct effect on PLA2. The response to calcium ionophore may reflect the differences in calcium requirements of the two endometrial PLA2 isoenzymes.     

Complete Genome Sequence of Hepatitis E Virus from Rabbits in the United States

Hepatitis E virus (HEV) is a single-strand positive-sense RNA virus in the family Hepeviridae. The disease caused by HEV, hepatitis E, is an important public health problem in developing countries of Asia and Africa and is also endemic in many industrialized countries, including the United States. HEV has been identified from several other animal species in addition to humans, including the pig, chicken, mongoose, deer, rabbit, ferret, bat, and fish. Here we report the complete genome sequence of the first strain of HEV from rabbits in the United States. Sequence and phylogenetic analyses revealed that the U.S. rabbit HEV is a distant member of the zoonotic genotype 3 HEV, thus raising a concern for potential zoonotic human infection. A unique 90-nucleotide insertion within the X domain of the ORF1 was identified in the rabbit HEV, and this insertion may play a role in the species tropism of HEV.