Sustainable use of insect resistance in crops require insect resistance management plans that may include a refuge to limit the spread of virulence to this resistance. However, without a loss of fitness associated with virulence, a refuge may not prevent virulence from becoming fixed within a population of parthenogenetically reproducing insects like aphids. Aphid-resistance in soybeans (i.e., ...

Three DNA regions (ITS 1, LSU rRNA and GPD) of isolates from the insectpathogenic fungus genus Entomophthora originating from different fly (Diptera) and aphid (Hemiptera) host taxa were sequenced. The results documented a large genetic diversity among the fly-pathogenic Entomophthora and only minor differences among aphid-pathogenic Entomophthora. The evolutionary time of divergence of the fly...

The soybean aphid, Aphis glycines Matsumura, is one of the most important economic pests affecting soybean production in Wisconsin and neighboring states. Since its discovery in 2000, the soybean aphid has become established in the North Central Region and presents a potential threat to the soybean industry. Insecticides are available for control of the soybean aphid, but are an additional prod...

The soybean aphid (Aphis glycines Matsumura) is native to China and Japan, and was a new pest in Iowa in 2000. Aphid numbers were high in the 2001, but in 2002 and 2003, aphids appeared to be less of a problem. This small, yellow aphid has distinct black cornicles (“tailpipes”) on the tip of the abdomen and develops colonies on soybean plants as winged and wingless forms. Aphids feed through pi...

The impacts of infestation by the green peach aphid (Myzus persicae) on sweetpotato whitefly (Bemisia tabaci) settling on tomato were determined in seven separate experiments with whole plants and with detached leaves through manipulation of four factors: durations of aphid infestation, density of aphids, intervals between aphid removal after different durations of infestation and the time of w...

In 2013, the sugarcane aphid, Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae), a new invasive pest of sorghum species in North America, was confirmed on sorghum in 4 states and 38 counties in the United States. In 2015, the aphid was reported on sorghum in 17 states and over 400 counties as well as all sorghum-producing regions in Mexico. Ability to overwinter on living annual and perenni...

Mustard (Brassica juncea L.) production in India suffers from aphid, Lipaphis erysimi (Kaltenbach), infestation considerably. Role of weather on the incidence and development of mustard aphids was assessed from experimental data from six north Indian locations. Aphid appearance and population build up was found to be regulated by temperature and time to attain peak population was relatively sho...

Soybean aphid is an economic pest of soybean in North America. Currently, management of soybean aphid is achieved through the use of foliar- and seed-applied insecticides. However, natural enemies play an important role in regulating soybean aphid populations, and may be adversely affected by insecticides. The effects of imidacloprid and thiamethoxam seed treatments on the soybean aphid parasit...

Since the introduction of the soybean aphid, Aphis glycines Matsumura, to the soybean growing regions of the United States, the soybean aphid has caused considerable economic damage and yield loss to soybean growers. The objectives of this research were to evaluate selected genotypes for resistance to the soybean aphid and characterize transcriptional changes in response to aphid feeding to bet...

Aphids (superfamily Aphidoidea) contain eubacterial endosymbionts localized within specialized cells (mycetocytes). The endosymbionts are essential for the survival of the aphid hosts. Sequence analyses of the 16S rRNAs from endosymbionts of 11 aphid species from seven tribes and four families have indicated that the endosymbionts are monophyletic. Furthermore, phylogenetic relationships within...