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. Ciche3, J.R. Ragains2, and R.A. Butcher1. 1Department of Chemistry, University of Florida, Gainesville, FL, 32611; 2Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803; and 3Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, 48824. Entomopathogenic nematodes survive inside the soil as stress-resistant infective juveniles (IJs) that seek out and infect insect hosts. Upon sensing internal host cues, the IJs regurgitate bacterial pathogens from their gut that in the end kill the host. Inside the host, the nematode develops into a reproductive adult and multiplies until unknown cues trigger the accumulation of IJs. Right here, we show that the entomopathogenic nematode Heterorhabditis bacteriophora utilizes a pheromone to handle IJ development. The pheromone, which probably increases in concentration at larger nematode densities, prevents IJ recovery towards the J4 stage, allowing IJs to amass late inside the infection procedure. Making use of activity-guided fractionation and NMR-based structure elucidation, we recognize the chemical structure in the pheromone. The pheromone is structurally connected towards the dauer pheromone ascarosides that the free-living nematode Caenorhabditis elegans utilizes to control its improvement. On the other hand, none on the C. elegans ascarosides are helpful in H. bacteriophora, suggesting that there’s a high degree of species specificity. Our report could be the initial to show that ascarosides are crucial regulators of development inside a parasitic nematode species. INCIDENCE OF PEACH TREE Brief LIFE Enhanced BY FOLIAR NICKEL APPLICATION. Nyczepir, Andrew P. and B.W. Wood. USDA-ARS, SE Fruit Tree Nut Study Laboratory, 21 Dunbar Road, Byron, GA 31008. Peach tree short life (PTSL) is reportedly brought on by a predisposition of trees to bacterial canker (Pseudomonas syringae pv. syringae van Hall), cold injury, or possibly a mixture of both, which is the consequence of root feeding by the ring nematode, Mesocriconema xenoplax. Specific micronutrients like nickel (Ni) are powerful in managing plant illnesses caused by fungi, bacteria, or nematodes (Meloidogyne sp) and are also critical mineral elements. The ability of postplant nickel (Ni) foliar application to suppress M. xenoplax population density and thereby prolong survival of peach trees on a PTSL site was investigated from 2004-2011. Plots consisted of three KYTH-105 custom synthesis therapies: i) Ni [foliar applied]; ii) methyl bromide fumigation (MBr); and iii) an untreated handle. Peach trees (`Dixiland’ on Nemaguard rootstock) have been planted into all plots in March 2005 and also the foliar Ni therapy was applied 3 instances in 2005 and 2006. Nickel did not detectably suppress M. xenoplax populations as compared to MBr fumigation. The effectiveness of MBr fumigation, as measured by M. xenoplax population density, collapsed 27 months just after orchard establishment. Trees receiving many foliar Ni applications at 0.45 g 21 more than two years, whilst exposed to M. xenoplax, exhibited higher (P 0.01) PTSL mortality than trees increasing in untreated or MBr fumigated plots. These outcomes recommend that foliar applications of Ni to peach trees, increasing on a PTSL website, can disrupt tree metabolic/physiological processes adequate to raise incidence of PTSL tree mortality and should hence be utilised with caution in commercial orchards. NEMATICIDES EFFECTS ON MELOIDOGYNE INCOGNITA AND ROTYLENCHULUS RENIFORMIS IN COTTON FIELDS WITH VARIABLE SOIL TEXTURE. Overstreet, Charles1, E.C.