BACKGROUND RNA interference (RNAi) is a powerful method to inhibit gene expression in a sequence specific manner. RESULTS Here, we described the development of RNAi by micro-injection of double-stranded RNA (dsRNA) in the pea aphid Acyrthosiphon pisum. Injection of dsRNA into whole aphid body induced the silencing of two marker genes with different expression patterns: the ubiquitously expres...

Pea aphids represent a complex genetic system that could be used for QTL analysis, genetic diversity and population genetics studies. Here, we described the development of first microsatellite repeat database of the pea aphid (APMicroDB), accessible at "http://deepaklab.com/aphidmicrodb". We identified 3,40,233 SSRs using MIcroSAtellite (MISA) tool that was distributed in 14,067 (out of 23,924)...

A major goal in evolutionary biology is to uncover the genetic basis of adaptation. Divergent selection exerted on ecological traits may result in adaptive population differentiation and reproductive isolation and affect differentially the level of genetic divergence along the genome. Genome-wide scan of large sets of individuals from multiple populations is a powerful approach to identify loci...

Previously we identified anterior localization of hunchback (Aphb) mRNA in oocytes and early embryos of the parthenogenetic and viviparous pea aphid Acyrthosiphon pisum, suggesting that the breaking of anterior asymmetry in the oocytes leads to the formation of the anterior axis in embryos. In order to study posterior development in the asexual pea aphid, we cloned and analysed the developmenta...

Soybean Dwarf Virus (SbDV) is an important plant pathogen, causing economic losses in soybean. In North America, indigenous strains of SbDV mainly infect clover, with occasional outbreaks in soybean. To evaluate the risk of a US clover strain of SbDV adapting to other plant hosts, the clover isolate SbDV-MD6 was serially transmitted to pea and soybean by aphid vectors. Sequence analysis of SbDV...

Aphids possess several facultative bacterial symbionts that have important effects on their hosts' biology. These have been most closely studied in the pea aphid (Acyrthosiphon pisum), a species that feeds on multiple host plants. Whether secondary symbionts influence host plant utilization is unclear. We report the fitness consequences of introducing different strains of the symbiont Hamiltone...

Pea enation mosaic virus (PEMV)--a plant RNA virus transmitted exclusively by aphids--causes disease in multiple food crops. However, the aphid-virus interactions required for disease transmission are poorly understood. For virus transmission, PEMV binds to a heavily glycosylated receptor aminopeptidase N in the pea aphid gut and is transcytosed across the gut epithelium into the aphid body cav...

Alfalfa (Medicago sativa) stem elongation is strongly reduced by a pea aphid (Acyrthosiphon pisum Harris) infestation. As pea aphid is a phloem feeder that does not transmit virus or toxins, assimilate withdrawal is generally considered as the main mechanism responsible for growth reduction. Using a kinematic analysis, we investigated the spatial distributions of relative elemental growth rates...

the distribution pattern of pest population is one of the factors not only effects on sampling program and data analysis method, but also can be used to measure the density of pests and their natural enemies. thus, the spatial distribution pattern of the pea aphid, acyrthosiphon pisum harris (hem.: aphididae) and its two major predators, hippodamia variegata goeze (col.: coccinellidae) and cocc...