Cap-independent internal initiation of translation occurs on a number of viral and cellular mRNAs and is directed by internal ribosome entry site (IRES) elements. Rhopalosiphum padi virus (RhPV) is a member of the Dicistroviridae. These viruses have single-stranded, positive-sense RNA genomes that contain two open reading frames, both preceded by IRES elements. Previously, the activity of the R...

Crop protection is an integral part of establishing food security, by protecting the yield potential of crops. Cereal aphids cause yield losses by direct damage and transmission of viruses. Some wild relatives of wheat show resistance to aphids but the mechanisms remain unresolved. In order to elucidate the location of the partial resistance to the bird cherry-oat aphid, Rhopalosiphum padi, in ...

Aphidius transcaspicus Telenga, a mealy plum aphid (Hyalopterus pruni Geoffroy) parasitoid from the Mediterranean, was recently introduced into Hawaii for control of invasive aphids. Under laboratory conditions the parasitoid successfully attacked several important aphid pests in Hawaii, including the melon aphid Aphis gossypii Glover, the banana aphid Pentalonia nigronervosa (Coquerel), the gr...

Plant material and aphid species 8 RNA extraction and measurements of RNA concentration with Nano-Drop 9 RT-PCR and agarose gel electrophoresis 10 Real-Time PCR 11 Bioinformatics: searching for sequences, sequence alignment 13 Results 15 Expression of callose synthase 15 Callose synthase expression analysis with RT-PCR 17 Callose synthase expression analysis with Real-Time PCR 20 Expression of ...

The new species Rhopalosiphum chusqueae Pérez Hidalgo & Villalobos Muller, is described from apterous viviparous females caught on Chusquea tomentosa in Cerro de la Muerte (Costa Rica). The identity of the species is supported both by the morphological features and by a molecular phylogenetic analysis based on a fragment of the mitochondrial DNA containing the 5' region of the cytochrome c oxid...

The presence of an endophytic fungus, Acremonium coenophialum, in tall fescue (Festuca arundinacea) deterred aphid feeding by Rhopalosiphum padi and Schizaphis graminum. Both species of aphid were unable to survive when confined to endophyte-infected tall fescue plants. Feeding deterrents and toxic factors to R. padi and Oncopeltus fasciatus, large milkweed bug, were primarily associated with a...

Dominance hierarchy, the dominance ranking of members in a community, is determined by relative population fitness coexisting species. Climate change can shift hierarchies depending on how species respond to changing climate, but ecological mechanisms underlying such shifts remain largely unknown. Specifically, hierarchy under climate have rarely been linked eco-evolutionary responses thermal e...

We present a preliminary attempt at applying an Allometric Trophic Network (ATN) model to single-season population data from agricultural fields. We describe the population dynamics of Rhopalosiphum padi, an aphid pest species, using predator-prey interactions that depend on the relative body masses of species in the food web. Using simple statistical assumptions, we formulate an inverse proble...