ABSTRACT Data collected in 2002 and 2003 on Alfalfa mosaic virus and Cucumber mosaic virus incidences of infection in commercial snap bean fields in New York State were used to develop relationships between disease incidence (p(low)) and sample size while accounting for the inherent spatial aggregation of infected plants observed with these two viruses. For a plan consisting of 300 sampled plan...

Despite evidence for biological control in North America, outbreaks of the invasive soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), continue to occur on soybean (Glycine max L. Merr.). Our objectives were to determine whether natural enemies delay aphid establishment and limit subsequent population growth and whether biological control can be improved by altering the within-fiel...

Growing concerns about the environmental consequences of chemically based pest control strategies have precipitated a call for the development of integrated, ecologically based pest management programs. Carabid or ground beetles (Coleoptera:Carabidae) are an important group of natural enemies of common agricultural pests such as aphids, slugs, and other beetles. Alfalfa (Medicago sativa L.) is ...

Medicago truncatula is attacked by a broad range of insect herbivores including sieve-element feeders, cell content feeders, and chewing insects. In M. truncatula, genetic resistance against insects has to date been identified only against aphids: single dominant resistance genes have been identified conferring resistance against the pea aphid, bluegreen aphid, and spotted alfalfa aphid. Aphids...

Populations of the most abundant alfalfa aphids, Acyrthosiphon pisum and Therioaphis trifolii, have periodic fluctuations, many factors affect their dynamics. In present study, we examined impact daily air temperatures on abundance two aphids in field conditions. The numbers these were documented at locations a representative growing area Serbia during three-year study. Based records aphid whol...

In the present study, field surveys were conducted to detect potential associational susceptibility of crop plants (potato, alfalfa and maize) caused by Canadian goldenrod, Solidago canadensis (L.), one most common invasive weeds in Central Eastern Europe, via plant associated virus vectoring aphids. Assessments made two major agricultural land types: crops grown under high input vs. low-input ...

Facultative bacterial endosymbionts can play an important role in the evolutionary trajectory of their hosts. Aphids (Hemiptera: Aphididae) are infected with a wide variety of facultative endosymbionts that can confer ecologically relevant traits, which in turn may drive microevolutionary processes in a dynamic selective environment. However, relatively little is known about how symbiont divers...

in this study, the biological effects of sugar beet leaf saponins on spotted alfalfa aphid was evaluated using thin layer chromatography. after saponin extraction from the leaf, three saponin concentrations together with a diet lacking saponin (control) were fed to aphids in five replications. the aphids’ survival and fertility were evaluated and analysed. results not only showed fertility impa...