Species of Xenorhabdus and Photorhabdus bacteria form mutualistic associations with Steinernema and Heterorhabditis nematodes, respectively and serve as model systems for studying microbe-animal symbioses. Here, we profiled gene expression of Xenorhabdus koppenhoeferi during their symbiotic persistence in the newly formed infective juveniles of the host nematode Steinernema scarabaei through th...

The vertical migration of N. carpocapsae infective juveniles applied to the soil surface or introduced 14 cm below the soil surface was studied in four different soil types (pure silica sand, coarse sandy loam, silty clay loam, and clay). The percentage of juveniles able to migrate and infect wax moth pupae placed in the soil decreased as the percentage of clay and silt increased. Most nematode...

Depolanmış ürün zararlıları, tarım ürünlerin depolama sürecinde hasat sonrası ciddi kayıplara neden olan en önemli biyotik faktörlerden biridir. Bu zararlılar ile mücadele amacıyla yıllardır yaygınlıkla pestisitler kullanılmaktadır. Ancak pestisitlerin ve ne olduğu kalıntıların hedef dışı organizmalar üzerinde oluşturduğu toksik etkiler bilinmektedir. nedenle, alanlarında biyolojik mücadelede y...

during conduction a survey of entomopathogenic nematodes throughout arasbaran forests and rangelands, north west of iran in 2007-2008, an entomopathogenic nematode was isolated using galleria baiting method from soil samples collected from rangelands, near chichakloo, varzeghan, east azarbaijan. it was identified as steinernema kraussei (steiner, 1923) travassos, 1927 based on morphology and mo...

Evolution of resistance by pests can reduce the efficacy oftransgenic crops that produce insecticidal toxins from the bacterium Bacillus thuringiensis Berliner (Bt). In conjunction with refuges of non-Bt host plants, fitness costs can delay the evolution of resistance. Furthermore, fitness costs often vary with ecological conditions, suggesting that agricultural landscapes can be manipulated to...

Mortality of larval, pupal, and adult western cherry fruit fly, Rhagoletis indifferens (Tephritidae) exposed to the steinernematid nematodes Steinernema carpocapsae, Steinernema feltiae, and Steinernema intermedium, was determined in the laboratory and field. Larvae were the most susceptible stage, with mortality in the three nematode treatments ranging from 62 to 100%. S. carpocapsae and S. fe...

There is considerable evidence that both plant diversity and plant identity can influence the level of predation and predator abundance aboveground. However, how the level of predation in the soil and the abundance of predatory soil fauna are related to plant diversity and identity remains largely unknown. In a biodiversity field experiment, we examined the effects of plant diversity and identi...

An insertion between iscA and hscB of the Xenorhabdus nematophila iscRSUA-hscBA-fdx locus, predicted to encode Fe-S assembly machinery, prevented colonization of Steinernema carpocapsae nematodes. The insertion disrupted cotranscription of iscA and hscB, but did not reduce hscBA expression, suggesting that X. nematophila requires coordinated expression of the isc-hsc-fdx locus for colonization.

Vol. XLI (February 2004), 101–115 101 *Rajdeep Grewal is Assistant Professor of Marketing, Smeal College of Business, Pennsylvania State University (e-mail: [email protected]). Raj Mehta is Associate Professor of Marketing (e-mail: [email protected]), and Frank R. Kardes is Professor of Marketing (e-mail: frank. [email protected]), College of Business Administration, University of Cincinnati. This resear...

Entomopathogenic nematodes (EPNs) can be highly effective biocontrol agents, but their efficacy can be reduced due to exposure to environmental stress such as from ultraviolet (UV) radiation. Our objectives were to 1) compare UV tolerance among a broad array of EPN species, and 2) investigate the relationship between reduced nematode viability (after exposure to UV) and virulence. Nematodes exp...