One hundred two Corynebacterium diphtheriae strains (93 of the gravis biotype and nine of the mitis biotype) isolated from clinical cases during the Belarus diphtheria epidemic were characterized by biotyping, toxigenicity testing by the Elek test and an indirect hemagglutination assay, phage typing, and ribotyping. The gravis biotype strains were characterized as high and medium toxin producer...

Rectal swabs (feacal) samples were collected from 518 sheep across Sokoto state and processed for Campylobacter organisms. Of a total of 518 samples, 93(18.0%) yielded Campylobacter organisms. The Campylobacter species isolated in this study were Campylobacter jejuni, Campylobacter coli, Campylobacter lari and Campylobacter upsaliensis. The most frequently isolated Campylobacter species was C. ...

A possible influence of low growth temperature on the photochemical activity of isolated mesophyll chloroplasts was studied in three biotypes of kochia [Kochia scoparia (L.) Schrad.] that showed either double resistance to both atrazine and acetolactate synthase (ALS) inhibitors (Bubny biotype), resistance to ALS inhibitors but not to atrazine (Jihlava biotype), or sensitivity to both types of ...

The Russian wheat aphid, Diuraphis noxia, an invasive phytotoxic pest of wheat, Triticum aestivum, and barley, Hordeum vulgare, causes huge economic losses in Africa, South America, and North America. Most acceptable and ecologically beneficial aphid management strategies include selection and breeding of D. noxia-resistant varieties, and numerous D. noxia resistance genes have been identified ...

BACKGROUND & OBJECTIVES Factor causing the elimination of the classical biotype of Vibrio cholerae O1, and its replacement by the El Tor biotype causing the 7 th cholera pandemic are unclear. Possible ability of the El Tor strains to adapt better than the classical strains to undefined environmental forces have been largely implicated for the change. Here we describe an environmental bacterioph...

It is known that plant viruses can change the performance of their vectors. However, there have been no reports on whether or how a semipersistent plant virus manipulates the feeding behaviors of its whitefly vectors. Cucurbit chlorotic yellows virus (CCYV) (genus Crinivirus, family Closteroviridae) is an emergent plant virus in many Asian countries and is transmitted specifically by B and Q bi...

Twenty-three Hessian fly, Mayetiola destructor (Say), populations collected in the southeastern (Alabama and Mississippi), midwestern (Indiana), and northwestern (Idaho and Washington) United States from 1995 to 1999 were evaluated for biotype composition based on response to Hessian fly resistance genes H3, H5, H6, and H7H8 in wheat, Triticum aestivum L. Biotypes L and O, combined, made up at ...

Rigid ryegrass (Lolium rigidum) is one of the most troublesome weeds in different crops in the Mediterranean region. A rigid ryegrass biotype from an olive grove in Jaén province (Andalusía, southern Spain), potentially resistant to glyphosate (RG), was tested for its resistance level through dose-response assays using a susceptible biotype (SG). To test the hypothesis of a non-target-site-base...

Vibrio cholerae biotype eltor serotype Ogawa cultures infected with temperate bacteriophage from lysogens of biotype eltor serotype Hikojima yielded types with altered agglutination reactions.

We previously reported that a velvetleaf (Abutilon theophrasti Medic) biotype found in Maryland was resistant to atrazine because of an enhanced capacity to detoxify the herbicide via glutathione conjugation (JW Gronwald, Andersen RN, Yee C [1989J Pestk Blochem Physiol 34: 149-163). The biochemical basis for the enhanced atrazine conjugation capacity in this biotype was examined. Glutathione le...