Bird cherry-oat aphid, (Rhopalosiphum padi /L./ (Hemi-ptera, Aphididae), is a holocyclic host-alternating species in temperate climates between wooden bird cherry, Prunus padus L. (Rosaceae) (winter, primary host) and grasses (summer, secondary hosts). In the spring, the aphid hatches from the winter eggs on P. padus and two wingless generations are developed before appearance of winged spring ...

Detailed investigation of virus replication is facilitated by the construction of a full-length infectious clone of the viral genome. To date, this has not been achieved for members of the family Dicistroviridae. Here we demonstrate the construction of a baculovirus that expresses a dicistrovirus that is infectious in its natural host. We inserted a full-length cDNA clone of the genomic RNA of ...

Rhopalosiphum padi virus (RhPV) (family Dicistroviridae; genus Cripavirus) is an icosahedral aphid virus with a 10kb positive-sense RNA genome. To study the molecular biology of RhPV, identification of a cell line that supports replication of the virus is essential. We screened nine cell lines derived from species within the Lepidoptera, Diptera and Hemiptera for susceptibility to RhPV followin...

Pathogens and parasites can induce changes in host or vector behavior that enhance their transmission. In plant systems, such effects are largely restricted to vectors, because they are mobile and may exhibit preferences dependent upon plant host infection status. Here we report the first evidence that acquisition of a plant virus directly alters host selection behavior by its insect vector. We...

Rhopalosiphum padi L. causes significant damage to winter wheat (Triticum aestivum L.), even without obvious aboveground symptoms of injury. Our objectives were to develop a juvenile-plant bioassay for bird cherry-oat aphid (BCOA) resistance that allows rapid phenotypic differentiation. Central features of the bioassay include root and shoot weight measurements of 3-week-old seedlings produced ...

In agricultural ecosystems, arthropod herbivores and fungal pathogens are likely to colonise the same plant and may therefore affect each other directly or indirectly. The fungus that causes powdery mildew (Blumeria graminis tritici) and cereal aphids are important pests of wheat but interactions between them have seldom been investigated. We studied the effects of powdery mildew of wheat on tw...

The toxicity effect of Concanavalin A (Canavalia ensiformis lectin, ConA) to bird cherry-oat aphid, Rhopalosiphum padi L. (Hemiptera: Aphididae), was investigated in the laboratory by using artificial diets containing ConA concentrations. Bird cherry-oat aphid performance was affected by the presence of Con A in artificial diets. The lectin added into the liquid diet increased the prereproducti...

The bird cherry-oat aphid (Rhopalosiphum padi), an important pest of cereal crops, not only directly sucks sap from plants, but also transmits a number of plant viruses, collectively the yellow dwarf viruses (YDVs). For quantifying changes in gene expression in vector aphids, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) is a touchstone method, but the selection and val...

A bicistronic baculovirus expression vector and fluorescent protein-based assays were used to identify the sequences that possess internal translation activity in baculovirus-infected insect cells. We demonstrated that the 5' untranslated region (5'UTR; 473 nucleotides) of Perina nuda virus (PnV) and the 5'UTR (579 nucleotides) of Rhopalosiphum padi virus (RhPV), but not the IRES sequence of Cr...

We show how a climatic niche model can be used to describe the potential geographic distribution of a pest species with variable life-history, and illustrate how to estimate biogeographic pest threats that vary across space. The models were used to explore factors that affect pest risk (irrigation and presences of host plant). A combination of current distribution records and published experime...