1 Swietenia macrophylla King (Meliaceae: Swietenioideae) provides one of the premier timbers of the world. The mahogany shoot borer Hypsipyla robusta Moore (Lepidoptera: Pyralidae) is an economically important pest of S. macrophylla throughout Asia, Africa and the Pacific. No viable method of controlling this pest is known. Previous observations have suggested that the presence of overhead shade may reduce attack by H. robusta, but this has not been investigated experimentally. This research was therefore designed to assess the influence of light availability on shoot-borer attack on S. macrophylla, by establishing seedlings under three different artificial shade regimes, then using these seedlings to test oviposition preference of adult moths, neonate larval survival and growth and development of shoot borer larvae. 2 Oviposition preference of shoot borer moths was tested on leaves from seedlings grown under artificial shade for 63 weeks. A significant difference in choice was recorded between treatments, with 27.4 AE 1.5 eggs laid under high shade and 87.1 AE 1.8 under low shade. 3 Neonate larval survival on early flushing leaflets of S. macrophylla did not differ significantly between shade treatments. Larval growth rate, estimated by measuring daily frass width, was significantly higher for those larvae fed on seedlings from the high and medium shade treatments (0.1 mm/day), than the low shade treatment (0.06 mm/day). In laboratory-reared larvae, the total mass of frass produced was significantly higher in the high shade treatment (0.4 g) than under the low shade treatment (0.2 g). 4 Longer tunnel lengths were bored by larvae in plants grown under high shade (12.0 AE 2.4 cm) than under low shade (7.07 AE 1.9 cm). However, pupal mass under low shade was 48% higher than that under the high shade treatment, suggesting that plants grown under high shade were of lower nutritional quality for shoot borer larvae. 5 These results indicate that shading of mahogany seedlings may reduce the incidence of shoot borer attack, by influencing both oviposition and larval development. The establishment of mahogany under suitable shade regimes may therefore provide a basis for controlling shoot borer attack using silvicultural approaches.

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We report here the genome sequences of two alphabaculoviruses of Helicoverpa spp. from Australia: AC53, used in the biopesticides ViVUS and ViVUS Max, and H25EA1, used in in vitro production studies.

Strength auditing of European honey bee (Apis mellifera Linnaeus, 1758 [Hymenoptera: Apidae]) colonies is critical for apiarists to manage colony health and meet pollination contracts conditions. Colony strength assessments used during pollination servicing in Australia typically use a frame-top cluster-count (Number of Frames) inspection. Sensing technology has potential to improve auditing processes, and commercial temperature sensors are widely available. We evaluate the use and placement of temperature sensing technology in colony strength assessment and identify key parameters linking temperature to colony strength. Custom-built temperature sensors measured hive temperature across the top of hive brood boxes. A linear mixed-effect model including harmonic sine and cosine curves representing diurnal temperature fluctuations in hives was used to compare Number of Frames with temperature sensor data. There was a significant effect of presence of bees on hive temperature and range: hives without bees recorded a 5.5°C lower mean temperature and greater temperature ranges than hives containing live bees. Hives without bees reach peak temperature earlier than hives with bees, regardless of colony strength. Sensor placement across the width of the hive was identified as an important factor when linking sensor data with colony strength. Data from sensors nearest to the hive geometric center were found to be more closely linked to colony strength. Furthermore, a one unit increase in Number of Frames was significantly associated with a mean temperature increase of 0.36°C. This demonstrates that statistical models that account for diurnal temperature patterns could be used to predict colony strength from temperature sensor data.

Complete genome sequences of two Australian isolates of H. armigera single nucleopolyhedrovirus (HaSNPV) and nine strains isolated by plaque selection in tissue culture identified multiple polymorphisms in tissue culture-derived strains compared to the consensus sequence of the parent isolate. Nine open reading frames (ORFs) in all tissue culture-derived strains contained changes in nucleotide sequences that resulted in changes in predicted amino acid sequence compared to the parent isolate. Of these, changes in predicted amino acid sequence of six ORFs were identical in all nine derived strains. Comparison of sequences and maximum likelihood estimation (MLE) of specific ORFs and whole genome sequences were used to compare the isolates and derived strains to published sequence data from other HaSNPV isolates. The Australian isolates and derived strains had greater sequence similarity to New World SNPV isolates from H. zea than to Old World isolates from H. armigera, but with characteristics associated with both. Three distinct geographic clusters within HaSNPV genome sequences were identified: Australia/Americas, Europe/Africa/India, and China. Comparison of sequences and fragmentation of ORFs suggest that geographic movement and passage in vitro result in distinct patterns of baculovirus strain selection and evolution.