Engineered expression of the invertebrate‐specific scorpion toxin AaHIT reduces adult longevity and female fecundity in the diamondback moth Plutella xylostella

Background: Previous Genetic Pest Management (GPM) systems in diamondback moth (DBM) have relied on expressing lethal proteins (‘effectors’) that are ‘cell‐autonomous’ i.e. do not leave the cell they are expressed in. To increase the flexibility of future GPM systems in DBM, we aimed to assess the use of a non cell‐autonomous, invertebrate‐specific, neurotoxic effector – the scorpion toxin AaHIT. This AaHIT effector was designed to be secreted by expressing cells, potentially leading to effects on distant cells, specifically neuromuscular junctions. Results: Expression of AaHIT caused a ‘shaking/quivering’ phenotype which could be repressed by provision of an antidote (tetracycline); a phenotype consistent with the AaHIT mode‐of‐action. This effect was more pronounced when AaHIT expression was driven by the Hr5/ie1 promoter (82.44% of males, 65.14% of females) rather than Op/ie2 (57.35% of males, 48.39% of females). Contrary to expectations, the shaking phenotype and observed fitness costs were limited to adults where they caused severe reductions in mean longevity (‐81%) and median female fecundity (‐93%). qPCR of AaHIT expression patterns and analysis of piggyBac‐mediated transgene insertion sites suggest that restriction of observed effects to the adult stages may be due to influence of local genomic environment on the tetO‐AaHIT transgene. Conclusion: We have demonstrated the feasibility of using non cell‐autonomous effectors within a GPM context for the first time in the Lepidoptera, one of the most economically damaging orders of insects. These findings provide a framework for extending this system to other pest Lepidoptera and to other secreted effectors

The BAYSOFI Campaign - Measurements Carried out during the Total Solar Eclipse of August 11, 1999

The total solar eclipse of August 11, 1999 provided a unique opportunity to observe the input of fast day-night and night-day transitions, under high solar elevation around noon, on the earth-atmosphere-biosphere system. Within the interdisciplinary field campaign BAYSOFI, measurements of radiation, boundary layer micrometeorology and photochemistry, photosynthesis and transpiration were carried out at Freising-Weihenstephan and several locations nearby focusing on short-term effects of the eclipse. Although the overall grosswetterlage on August 11 was not favourable for viewing the eclipse, with clouds covering most of central Europe, observational conditions at Weihenstephan were fair due to a large hole in the cloud layer which appeared just half hour before totality lasting for more than one hour. Thus significant effects of the eclipse on radiation, photolysis rates, OH, the temperature, wind, turbulence structure and stratification, ozone and CO2 fluxes, photosynthesis, transpiration and sap flow of trees could be observed which are reported and discussed in the following sequence of papers