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The entomopathogenic nematodes Steinernema weiseri, S. feltiae, S. carpocapsae and two strains of Heterorhabditis bacteriophora, isolated from Turkish soils, were evaluated against larvae of the Mediterranean fruit fly (medfly) Ceratitis capitata in plastic cups under laboratory conditions with sandy loam soil and 10% moisture level. At a rate of 100 infective juveniles (IJs)/cm 2 , the last instar larvae of C. capitata were susceptible to the entomopathogenic nematodes: the S. feltiae 09-31 strain recovered from Aydin provided 78% mortality, whereas S. weiseri and S. carpocapsae killed 50% and 56% of the larvae, respectively. Both strains of H. bacteriophora species caused less than 50% mortality. Except for S. feltiae, the majority of infected medflies died as prepupae or pupae within the puparia. More than 90% larval mortality was recorded at 200 and 400 IJs/cm 2 for S. feltiae. None of the nematode isolates infected the medfly pupae within the puparia. In pot experiments containing soil, S. feltiae caused 96% and 97% mortality at 100 and 200 IJs/cm 2 , respectively. In pot experiments with grass present, more than 94% mortality was obtained in the presence of grass roots.

Natural products have been proven to be important starting points for the development of new drugs. Bacteria in the genera Photorhabdus and Xenorhabdus produce antimicrobial compounds as secondary metabolites to compete with other organisms. Our study is the first comprehensive study screening the anti-protozoal activity of supernatants containing secondary metabolites produced by 5 Photorhabdus and 22 Xenorhabdus species against human parasitic protozoa, Acanthamoeba castellanii, Entamoeba histolytica, Trichomonas vaginalis, Leishmania tropica and Trypanosoma cruzi, and the identification of novel bioactive antiprotozoal compounds using the easyPACId approach (easy Promoter Activated Compound Identification) method. Though not in all species, both bacterial genera produce antiprotozoal compounds effective on human pathogenic protozoa. The promoter exchange mutants revealed that antiprotozoal bioactive compounds produced by Xenorhabdus bacteria were fabclavines, xenocoumacins, xenorhabdins and PAX peptides. Among the bacteria assessed, only P. namnaoensis appears to have acquired amoebicidal property which is effective on E. histolytica trophozoites. These discovered antiprotozoal compounds might serve as starting points for the development of alternative and novel pharmaceutical agents against human parasitic protozoa in the future.

Bursaphelenchus debrae n. sp. was cultured from dauer juveniles recovered from the poison sac of a female sweat bee, Halictus brunnescens from Ankara, Turkey, in June 2004. The new species appears to be most similar to B. kevini and B. anatolius based upon the synapomorphies of their associations with soil-dwelling halictid bees, morphological features such as four lateral incisures, male caudal papillae arrangement, spicule morphology, female tail shape and ratio a, and molecular analysis of sequences of the D2/D3 expansion segments of the large subunit (LSU) rDNA and partial mitochondrial DNA COI (mtCOI). In addition to significant molecular sequence differences in LSU and COI consistent with separate species status, B. debrae n. sp. can be differentiated from both B. kevini and B. anatolius by differences in the host halictid bee species with which they are phoretically associated, rostrum shape and size, and presence of a unique protuberance on the ventral aspect of the spicules. The nematode is mycophagous and can be cultured in the laboratory at 23 • C on Monilinia fructicola growing on lactic acid-treated, 5% glycerin-supplemented potato dextrose agar (LGPDA).