Cyst nematodes hatch in higher numbers in response to unknown signaling compounds in host-specific root exudates. We prepared root MedChemExpress SIS3 diffusates from tobacco or eastern black nightshade roots by soaking 8 g of root in 400 ml distilled water for two hrs. Diffusates had been filtered and frozen until use. Full-strength or 1:10 and 1:one hundred dilutions of diffusates have been percolated though 100 cm3 pasteurized sandy loam soil or soil amended with biochar (Agrichar, Very best Energies, Inc., Madison WI) at prices of 1 or ten biochar by volume. Collected diffusates have been then added to five or six replicate hatch chambers each and every containing 15 cysts of Globodera tabacum along with the numbers of hatched juveniles counted more than time. The experiment was conducted twice with equivalent final results. Juvenile hatch from cysts exposed to diffusates leached by way of biochar-amended soil was substantially lowered in comparison with diffusates leached through non-amended soil (P=0.002). Each 1 and 10 biochar amendments were helpful in lowering juvenile hatch from full-strength root diffusate to levels similar to water alone or the 100-fold dilution of your root diffusate handle, which weren’t different. Biochar may well adsorb host-specific hatch signaling compounds, disrupting G. tabacum host recognition and subsequent hatch stimulation. ENTOMOPATHOGENIC SYMBIOSIS OF CAENORHABDITIS BRIGGSAE KT0001 AND SERRATIA SP. SCBI: Evaluation OF FITNESS. Lancaster, Jeremiah D., B. Mohammad, and E. Abebe. Division of Biology, Elizabeth City State University, 1704 Weeksville Road, Elizabeth City, NC, 27909. Substantial research effort has advanced our understanding of Caenorhabditis as a model system, but its all-natural association with bacteria remains unexplored in an ecological context. Explored associations vary vastly from mutualistic to parasitic. Serratia marcescens has been shown to be pathogenic to Caenorhabditis using a fitness cost. The current isolation of an entomopathogenic Caenorhabditis briggsae KT0001/S. marcescens SCBI association in the wild has permitted us to examine under laboratory situations regardless of whether such an association poses a serious cost to Caenorhabditis as previously surmised for other Serratia. A fecundity table of Caenorhabditis briggsae KT0001 fed on S. marcescens SCBI and also the control fed on E. coli OP50 is presented. We identified no important distinction in survivorship or total fecundity in between the S. marcescens SCBI fed and E. coli OP50 fed Caenorhabditis briggsae KT0001. Only the mean onset of reproduction was474 Journal of Nematology, Volume 44, No. four, December 2012 drastically diverse between the two groups with E. coli fed C. briggsae maturing earlier (2.12 days) than those fed on Serratia (2.42 days). S. marcescens SCBI is probably not pathogenic to C. briggsae KT0001 indicating that the entomopathogenicity reported for this association is valuable for each the nematode and bacteria. In light of the fact that hitherto conducted experimental tests conform to widely held view that Serratia are pathogenic to Caenorhabditis, the absence of a fitness cost for C. briggsae we report right here may well indicate that this entomopathogenic association is non-transientsuggesting nematode/bacterial associations inside the wild could differ drastically. Consequently, broad generalizations about nematode/ bacterial associations need to be interpreted with care. EFFECTS OF ENVIRONMENTAL Factors On the SEX DIFFERENTIATION OF SOUTHERN ROOT-KNOT NEMTAODE (MELOIDOGYNE INCOGNITA).