A series of bioassays were conducted to determine the relative toxicities and residual activities of insecticides labeled for use in blueberry (Vaccinium corymbosum L.) on natural enemies, to identify products with low toxicity or short duration effects on biological control agents. In total, 14 insecticides were evaluated using treated petri dishes and four commercially available natural enemi...

In surveys of apple-production areas east of the Cascade Mountains of Washington, broadleaf plantain, Plantago major Linnaeus (Plantaginaceae) was common throughout while narrowleaf plantain, P. lanceolata Linnaeus, was most common south of Orondo, Douglas County (47.7u latitude). Rosy apple aphid was the most common aphid on these two herbaceous plants; however, colonies were scarce, on only 1...

To assess biological control as a management tool for the cotton aphid, Aphis gossypii Glover (Homoptera: Aphididae), the efficacy of Aphidius colemani Viereck (Hymenoptera: Braconidae) for suppression of A. gossypii in greenhouse-grown chrysanthemums, Dendranthema grandiflora (Tzvelev), was compared with a pesticide standard, imidacloprid (Marathon 1% G) and an untreated check. No significant ...

Parasitoids are among the most important natural enemies of insects in many environments. Acyrthosiphon pisum, the pea aphid, is a common pest of the leguminous crops in temperate regions. Pea aphids are frequently attacked by a range of endoparasitic wasps, including the common aphidiine, Aphidius ervi. Immunity to parasitoid attack is thought to involve secondary symbiotic bacteria, the prese...

Aphids commonly harbor bacterial facultative symbionts that have a variety of effects upon their aphid hosts, including defense against hymenopteran parasitoids and fungal pathogens. The soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is infected with the symbiont Arsenophonus sp., which has an unknown role in its aphid host. Our research goals were to document the infection fre...

Planting Bt cotton in China since 1997 has led to important changes in the natural enemy communities occurring in cotton, however their specific effect on suppressing the cotton aphids (being notorious in conventional cotton ecosystem) has not been fully documented yet. We observed strong evidence for top-down control of the aphid population, e.g. the control efficiency of natural enemies on co...

Edward B. Mondor,* Michelle N. Tremblay and Richard L. Lindroth Department of Entomology, University of Wisconsin, Madison, WI 53706, USA *Correspondence: E-mail: [email protected] Abstract Organisms often exhibit transgenerational phenotypic changes in response to an increased risk of parasitism or predation. Shifts in global atmospheric composition could modify these phenotypic effec...

It has been hypothesized that the success of a biological control introduction is, in part, dependent on the ability of the control agent to become established in its new environment or to its new population of hosts through local adaptation. Despite this, few studies have investigated the influence of the recent coevolutionary history of pest species and natural enemies on the efficacy of biol...