We examined the physiological and biochemical responses of resistant ('Halt' and 'Prairie Red') and susceptible ('TAM 107') wheat, Triticum aestivum L., to injury by the Russian wheat aphid, Diuraphis noxia (Mordvilko). Photosynthetic capacity was evaluated by measuring assimilation/internal CO2 (A/Ci) curves, chlorophyll fluorescence, chlorophyll, and nonstructural carbohydrate content. Total ...

The Russian wheat aphid, Diuraphis noxia (Mordvilko) (Homoptera: Aphididae), has been a major economic pest of small grains in the western United States since its introduction in 1986. Recently, a new Russian wheat aphid biotype was discovered in southeastern Colorado that damaged previously resistant wheat, Triticum aestivum L. Biotype development jeopardizes the durability of plant resistance...

The abundance and distribution of microsatellites, or simple sequence repeats (SSRs) were explored in the expressed sequence tag (EST) and genomic sequences of the pea aphid, Acyrthosiphon pisum (Harris), and the green peach aphid, Myzus persicae (Sulzer). A total of 108 newly developed, together with 40 published, SSR markers were investigated for their cross-species transferability among six ...

The invasion of ecological systems by nonindigenous species is now recognized as a growing global problem that imposes significant economic and ecological damages. In the United States alone, the total costs of nonindigenous species have been estimated to be at least $137 billion per year (Pimentel et al.). Approximately one-fourth of the value of the country’s agricultural output is lost to no...

The Russian wheat aphid, Diuraphis noxia (Kurdjumov) (Hemiptera: Aphididae), is a serious wheat, Triticum aestivum L., and barley, Hordeum vulgare L., pest throughout the small grain-producing areas in the western United States. The virulency and classiÞcation of recently described Russian wheat aphid biotypes 1Ð7 (RWA1Ð7) were clariÞed using 24 plant differentials. These seven biotypes had bee...

in this study, the effects of two metarhizium anisopliae isolates, originally obtained from red palm weevil (rhynchophorus ferrugineus) and a beetle (parandra caspica), on adults of russian wheat aphid diuraphis noxia were studied under laboratory coditions. after a determination of the minimum & maximum concentrations, the adults were treated with conidial concentrations of 1×103 to 1×106 coni...

Elicitors are molecules which can induce the activation of plant defence responses. Elicitor activity of intercellular wash fluid from Russian wheat aphid, Diuraphis noxia (Mordvilko) infested resistant (cv Tugela DN), and susceptible (cv Tugela), wheat (Triticum aestivum L.), was investigated. Known Russian wheat aphid resistance related responses such as peroxidase and beta-1,3-glucanase acti...

The effects of feeding by the Russian wheat aphid (RWA), Diuraphis noxia Mordvilko and the Bird cherry-oat aphid (BCA), Rhopalosiphum padi L on the transport capacity of barleyHordeum vulgare L leaves were investigated and compared with a view to relating these effects to the visible symptoms shown by the respective infested plants. RWAcauses extensive chlorosis and necrosis on an infested plan...