The multicolored Asian ladybeetle, Harmonia axyridis Pallas (Coleoptera: Coccinellidae), was introduced into Western Europe in the late 1990s. Since the late 2000s, this species has been commonly considered one of the most abundant aphid predators in most Western European countries. In spite of the large amount of research on H. axyridis, information concerning its relative abundance in agroeco...

in order to evaluate the response of russian knapweed seeds to cardinal temperatures a factorial experiment was conducted base on completely randomized design with 3 replications. russian knapweed seeds (collected from irrigated and rainfed wheat fields), and germination temperatures (constant temperatures of 10, 15, 20, 25, 30 and 35° c) were used as first and second levels of the experiment. ...

The Russian wheat aphid (RWA), Diuraphis noxia (Kurdjumov), is one of the main pests small-grain cereal crops, including bread wheat, Triticum aestivum (Poaceae). In a series glasshouse experiments, we evaluated systemic effect endophytic Beauveria bassiana strain PPRI 7598 on D. biotype RWASA1 using three South African cultivars, Gariep, Molopo, and Kariega. objectives study were: (a) to deter...

Clonal populations of the aphid, Schizaphis graminum, have been separated into biotypes based on host preference and their ability to overcome resistance genes in wheat. Recently, several biotypes were found to differ in their ability to transmit one or more of the viruses that cause barley yellow dwarf disease in grain crops, and vector competence was linked to host preference. The genetics of...

Clonal populations of the aphid, Schizaphis graminum, have been separated into biotypes based on host preference and their ability to overcome resistance genes in wheat. Recently, several biotypes were found to differ in their ability to transmit one or more of the viruses that cause barley yellow dwarf disease in grain crops, and vector competence was linked to host preference. The genetics of...