Genome sizes were measured and determined for the karyotypes of nine species of aphid parasitoids in the genus Aphelinus Dalman,1820. Large differences in genome size and karyotype were found between Aphelinus species, which is surprising given the similarity in their morphology and life history. Genome sizes estimated from flow cytometry were larger for species in the Aphelinus mali (Haldeman,...

abstract in a laboratory study the effect of three insecticides (pirimicarb, pymetrozine and spinosad) was evaluated on aphelinus mali a parasitoid of woolly apple aphid. to investigate the contact effect, adults were caged for 16 hours in petri-dishes containing apple leaves sprayed with each insecticide. to determine the oral toxicity in the same period of time, other petri-dishes containing ...

A multilateral approach that includes both biotic and climatic data was developed to detect the main variables that affect the ecology and population dynamics of woolly apple aphid Eriosoma lanigerum (Hausmann). Crawlers migrated up and down the trunk mainly from spring to autumn and horizontal migration through the canopy was observed from May to August. Winter temperatures did not kill the ca...

Diversifying agroecosystems through habitat management inside or outside production fields can provide alternative hosts and/or prey for natural enemies. In semi-natural habitats, parasitoids may find host-plant complexes (HPC) that could allow their development when pest are scarce in the field. However, morphological and physiological differences between targeted HPCs affect preference fitnes...

Aphelinus mali (Haldeman) (Hymenoptera: Aphelinidae) is an effective natural enemy used in China to control the woolly apple aphid (Eriosoma lanigerum [Hausmann]) (WAA). Population of A. mali in China falls into two distinct genetic clades (Shandong clades and Liaoning clades). In the present results, the developmental threshold temperature of the Shandong clade (9.82 ± 1.44 °C) was lower than ...

Woolly apple aphid, Eriosoma lanigerum (Hausmann), has become a pest of increasing importance in Washington apple orchards in the past decade. The increase in aphid outbreaks appears to be associated with changes in pesticide programs and disruption of biological control. We sampled woolly apple aphid colonies in central Washington apple orchards for natural enemies of this pest from 2006 to 2...