two different viruses were isolated from sugar beet growing areas in karaj, which caused mosaic symptoms. collected samples were classified in two different groups. the host range of the first group was confined to some species in chenopodiaceae and amaranthaceae families. the sap of infected plants reacted positively with beet mosaic virus antisera in ouchterlony double-diffusion test. electro...

Background: It is generally assumed that short-term population dynamics are too slow to be influenced by evolution. Question: Can evolution occurring within only weeks (four to five generations) impact concurrent population dynamics? Organism: Green peach aphid (Myzus persicae) growing on an undomesticated host (Hirschfeldia incana). Aphid clones were collected from a single wild population. Si...

The green peach aphid, Myzus persicae (Sulzer), is a major insect pest of many agronomic and horticultural crops and is distributed worldwide. Aphid management is often based on application of insecticides. However, the aphid is now resistant to many of these and much interest has recently developed in identification of novel alternative insecticides. Venom isolated from the red imported fire a...

Aphids are sap-sucking insects that mainly attack shoots and young leaves of peach trees and many other plant species; however, knowledge of the Brazilian aphid fauna is scant. The objective of this study was to identify aphid species collected in peach orchards (Prunus persica Batsch) and to determine their faunal indices for occurrence and dominance. The experiment was conducted from July 200...

functional response, as describing the rates of predation in different prey density, and determining the predator efficiency, is important in the regulation of prey populations. the functional response of male and female adult of lady beetle, hippodamia variegata, was studied at different densities of green peach aphid under laboratory conditions on canola brassica napus l. (cv. rgs003). nymphs...

The phloem provides a unique niche for several organisms. Aphids are a large group of Hemipteran insects that utilize stylets present in their mouthparts to pierce sieve elements and drink large volumes of phloem sap. In addition, many aphids also vector viral diseases. Myzus persicae, commonly known as the green peach aphid (GPA), is an important pest of a large variety of plants that includes...