The nutritive value of two cereal aphid species, Schizaphis graminum and Rhopalosiphum padi, for Hippodamia convergens development was compared as pureand mixed-species diets and as suboptimum and ad libitum quantities. Comparisons were based on the following daily aphid quantities and combinations: 4 mg R. padi, 4 mg S. graminum, 3:1 mg mixture of R. padi and S. graminum, 2:2 mg mixture of R. ...

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...

Holocyclic clones of the aphid Rhopalosiphum padi (L.) reproduce by cyclic parthenogenesis, whereas anholocyclic individuals are obligate parthenogens. Mitochondrial DNA and (mtDNA) and random amplified polymorphic DNA markers in R. padi as well as plasmid DNA markers of its bacterial endosymbiont, Buchnera aphidicola, were examined to determine the extent of genetic divergence between clones w...

The impacts of aqueous extracts from different parts (root, stem, leaf and fruit) of bitter apple Citrullus colocynthis (Cucurbitales: Cucurbitaceae), with five different concentrations, on controlling the bird cherry-oat aphid, Rhopalosiphum padi (L.) (Homoptera: Aphididae) were investigated under laboratory conditions. Results showed that the effects of the aqueous extracts from different par...

We applied DNA sequence analysis to Rhopalosiphum aphids, which we had previously characterised by random amplified polymorphic DNA (RAPD) PCR. By comparing two gene sequences, we confirmed that Rhopalosiphum sp. T was a species previously undescribed from New Zealand. Significant differences were also observed between a DNA sequence from New Zealand R. near insertum and a European R. insertum ...

In cereal cropping systems of the Pacific Northwestern United States (PNW), climate change is projected to increase the frequency of drought during summer months, which could increase water stress for crop plants. Yet, it remains uncertain how interactions between herbivore species are affected by drought stress. Here, interactions between two cereal aphids present in PNW cereal systems, Metopo...

The furanoeremophilanes 6 beta-angeloyloxy-1,10-dehydrofuranoeremophilan-9-one (1), 6 beta-hydroxy-1,10-dehydrofuranoeremophilan-9-one (2) and 6 beta-propionyloxy-1,10-dehydrofuranoeremophilan-9-one (3) were isolated from Senecio otites, their structures elucidated by spectral analyses, and their insecticidal and phytotoxic properties evaluated. Compounds 1-3 proved to be effective aphid antife...

The bird cherry-oat aphid, Rhopalosiphum padi (L.), is one of the most abundant aphid pests of cereals and has a global distribution. Next-generation sequencing (NGS) is a rapid and efficient method for developing molecular markers. However, transcriptomic and genomic resources of R. padi have not been investigated. In this study, we used transcriptome information obtained by RNA-Seq to develop...