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Wheat (Triticum spp.) is highly susceptible to the root lesion nematode, Pratylenchus thornei, which causes excessive amounts of crop losses each year. In this research, we investigated the cumulative effect of the biocontrol agent Purpureocillium lilacinum (syn: Paecilomyces lilacinus) against P. thornei. Three doses of P. lilacinum (106, 107 and 108 conidia cultures mL-1) with one dose of 400 P. thornei individuals (adults and juveniles) mL-1 were applied in 100 cm3 soil under greenhouse conditions. The number of nematodes in the soil and root in addition to total nematode in soil+root were determined. Moreover, different plant parameters such as the plant height, plant fresh and dry weight, root fresh and dry weight were evaluated. Applications with the higher dose of bio-agents (100 cm3 P. thornei infested soil with 108 conidia culture of P. lilacinum mL-1) exhibited maximal enhancement in dry and fresh weight of shoot and reduced P. thornei population. As a consequence, P. lilacinum individually was highly effective in enhancing different plant parameters and suppressing P. thornei reproduction. Overall, present findings suggest that the exploitation of the biocontrol agent P. lilacinum could be helpful for effective management of the root lesion nematode P. thornei.

Bu çal ışmada Gönen (Bal ı kesir) ve Kızı lcahamam (Ankara) ilçelerinde çeltik (Oryza sativa L.) ekiliş alanları ndan al ınan 20 adet toprak örne ğ i incelenmiştir. Al ı nan örneklerden elde edilen bitki paraziti nematodlardan Pratylenchoides Wislow (Nematoda:Pratylenchidae) cinsine ait türlerin daimi preparatlar ı hazırlanarak, ölçüm ve teşhisleri yap ı lmışt ı r. Çal ışmada bu cinse ait P. utahensis Baldwin, Luc & Bell ve P. variabilis Sher olmak üzere 2 tür saptanm ış olup, bu türler Türkiye nematod faunas ı için yeni kay ı t niteli ğindedir. Bu türlerin morfolojik ve morfometrik özellikleri, görülen varyasyonlar, literatürde kay ıtl ı yay ı l ışı ve biyotoplar ı verilmiştir.

Entomopatojen nematodlar olarak Steinemema, Neosteinemema (Rhabditida: Stelnernematidae) ve Heterorhabditis (Rhabditida Heterorhabditidae ) cinslerine ait türler, böceklerle biyolojik mücadelede, diğer nematod gruplarına göre çok daha önemli bir yere sahiptir. Steinemema feltiae (Filipjev 1934) Woust, Mracek, Gerdin and Bedding, 1982 ülkemizde ilk kaydedilen entomopatojen nematod türüdür. Bu tür, Özer et al (1995) tarafından Rize' de tespit edilmiştir Bu çalışmada, Ankara Üniversitesi, Ziraat Fakültesi Kampüs alanından alınan toprak örnekleri içerisinden Heterorhabditis marelatus Liu and Berry 1996 (Rhabditida Heterorhabditidae) bulunmuştur Söz konusu türün erkek birey ve enfektif larvalarına ait morfolojik ve morfometrik özellikleri belirlenerek orijinal tanımı ile karşılaştırılmış, hayat çemberi kontrollü koşullarda takip edilmiş ve literatür kayıtlarına göre yayılış alanı ve konukçuları hakkında bilgi verilmiştir Çalışmada saptanan H marelatus Türkiye nematod faunası için yeni kayıt niteliğindedir.

İn this study, plant parasitic nematodes species of Tylenchida İn vvalnuts (Juglans regia L.) and chestnuts (Castanea sativa Miller) orchards in some provlnces of the Black Sea Region are examined. VVith this, totally 21 species were determined of which this species belonging to 17 genus of 7 families of Tylenchoidea, Dolichodoridea, Hoplolaimoidea, Criconematoidea, Hemicycliophoroidea, Anguinoidea superfamilies of Tylenchina, Criconematina, Hexatyllna (Tylenchina: Nematoda) suborder. İt vvas not met any literatüre record about nematodes on vvalnuts and chestnuts in Turkey, in the end of this study 14 plant parasitic nematodes İn walnuts and 10 plant parasitic nematodes in chestnuts vvere determined. Among them; Boleodorus (B.) acutus Thorne and Malek, Nagelus saifulmulukensis Maqbool and Shahina and Rotylenchus robustus (de Man) Filipjev are determined for the first time in the Nematoda fauna of Turkey.

Abstract Background The wheat stink bug, Aelia rostrata Boheman (Hemiptera: Pentatomidae), is one of the harmful insects that caused significant product losses in cereals due to outbreaks. Entomopathogenic nematodes (EPNs) are natural enemies of soil insect pests whose effects as a biocontrol agent against many harmful pests have been demonstrated by many laboratories and field/garden studies in the world. The present laboratory studies, using native EPNs [Steinernema carpocapsae (Black sea isolate), S. feltiae (isolate 09-31) (Aydin isolate) and Heterorhabditis bacteriophora (isolate 09-43) (Aydin isolate)] against the wheat stink bug adults, were carried out. Results In the application of EPNs to the soil in plastic cups, the highest mortality rates (75 and 70%) on wheat stink bug occurred at 200 IJs cm−2 concentration of S. carpocapsae isolate at 15 and 12 °C, respectively. In other tested nematode species, the highest insect mortality was observed at 200 IJs cm−2 concentration of S. feltiae and H. bacteriophora isolates, with mortality rates of 65–35% and 55–25%, at 15 and 12 °C, respectively. S. carpocapsae (Black sea isolate) was the most pathogenic among the three nematodes tested. Conclusions It was concluded that S. carpocapsae had the potential as a biocontrol agent against the wheat stink bug, A. rostrata. The applications of S. carpocapsae were the great potential for the management of the pest. Effective use of EPNs should be evaluated in integrated pest management strategies between other biological control agents. According to EPNs laboratory experiments results, field trials should be conducted in future studies.

Abstract Background The cotton leafworm, Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae), is an economic pest on various crops worldwide. Farmers generally used to apply chemical pesticides to control the pest. The bio-control potential of the entomopathogenic nematodes (EPNs) as alternatives to harmful synthetic pesticides was examined in this study. The study aimed to determine the efficacy of EPNs isolates against the different stages of larvae of the cotton leafworm S. littoralis and the effect of time on mortality rate under laboratory conditions. Results EPNs isolates were tested at 4 different concentrations (0, 250, 500 and 1000 IJs/ml) in 150 ml plastic containers on last instar larvae (sixth instar) of S. litorallis. Experiments for third, fourth and fifth instar larvae of S. litorallis were carried out in petri dishes at different concentrations (0, 50, 100 and 200 IJs/ml) at 25 °C temperature. Mortality rates of larvae were calculated at 3 different times (48, 72, 96 h) after inoculation. The high mortality rate of last instar larvae (98.81%) of S. littoralis was caused by Steinernema feltiae (Tokat-Emir), followed by S. carpocapsae (Tokat-Bakışlı05) (95.24%) and then H. bacteriophora (11 KG) with (90.47%) at the highest concentration (1000 IJ/ml). The highest mortality rate of fifth instar larvae was caused by S. feltiae (Tokat-Bakışlı05) and S. carpocapsae (Tokat-Emir) with (100%) and (92.12%). In addition, the highest mortality rate of the 4th instar larvae was determined S. feltiae (Tokat-Bakışlı05) and S. carpocapsae (Tokat-Emir) isolates (98.87%) and (97.74%), respectively. Additionally, the highest larval mortality rate in the third stage by S. feltiae (Tokat-Bakışlı05) and S. carpocapsae (Tokat-Emir) was (100%) and (97.74%) at the highest concentration. Mortality rates of larvae were calculated at 3 different times after inoculation. The highest mortality rate counted in all isolates was determined 96 and 72 h after inoculation of EPNs. Conclusions All indigenous EPN isolates were found to be effective at different rates against S. littoralis. The results showed that these nematode species could be used against S. littoralis biological control programs.

Abstract Background Entomopathogenic nematodes (EPNs) have more important role in biological control of economic insect pests. The effect of native EPNs on adults of the lucerne beetle, Gonioctena fornicata (Brüggemann, 1873) (Coleoptera: Chrysomelidae), and the alfalfa weevil, Hypera postica (Gyllenhal, 1813) (Coleoptera: Curculionidae), which are important alfalfa pests in Turkey and around the world, was investigated. Results Dose-mortality assays were carried out with 5 isolates [Steinernema carpocapsae (Weiser, 1955) (Nematoda: Steinernematidae) (Black sea isolate), S. feltiae Filipjev, 1934 (isolate 09-31), Heterorhabditis bacteriophora Poinar, 1976 (Nematoda: Heterorhabditidae) (isolate 09-43), H. bacteriophora Tokat-Songut, and S. carpocapsae Tokat-Ulas] using doses of 500, 1000, and 2000 IJs ml−1 under the laboratory conditions. Studies showed that all isolates had an effect 90% and more at 2000 IJs ml−1 and at the end of 112 h [except, H. bacteriophora (isolate 09-43) and H. bacteriophora Tokat-Songut isolates against H. postica]. In addition, LT30, LT50, and LT90 values at 1000 IJs ml−1 were determined. Conclusions According to the results, G. fornicata adults were susceptible to all isolates tested in the study and H. postica adults were susceptible to the isolates S. carpocapsae (Black sea isolate), S. feltiae (isolate 09-31), and S. carpocapsae Tokat-Ulas. This is the first study conducted in Turkey for the virulence of EPNs against G. fornicata and H. postica.

Efficacy of three Turkish isolates of the entomopathogenic nematodes; Steinernema carpocapsae, S. feltiae and Heterorhabditis bacteriophora were evaluated against the great spruce bark beetle Dendroctonus micans (Kugelann) (Coleoptera: Scolytidae) larvae under laboratory conditions. Optimum nematode application rate and temperature were determined. The experiments were conducted testing the concentrations of 100, 500 and 1000 infective juveniles (IJs) at 10, 15 and 25°C. Temperature and nematode concentration had significant effects on D. micans larval mortality. Generally, S. feltiae and H. bacteriophora species displayed mortality increase in parallel with rising temperature and number of applied IJs. At 25°C and 1000 IJs concentration, larval mortality attained 98.04 and 94.04% for S. feltiae and H. bacteriophora, respectively, while S. carpocapsae did not exhibit more than 40% mortality at any of the temperatures and/or the concentrations applied. At 25°C, infected cadaver application showed 94.04, 86.93 and 38.84% mortality for S. feltiae, H. bacteriophora and S. carpocapsae, respectively. [ABSTRACT FROM AUTHOR]

Turkish isolates of the entomopathogenic nematodes, Steinernema feltiae (Filipjev), S. carpocapsae (Weiser) and Heterorhabditis bacteriophora Poinar (EPNs) (Rhabditida: Steinernematidae and Heterorhabditidae) were isolated and tested against the black cherry aphid (BCA), Myzus cerasi (F.) (Hemiptera: Aphididae) adults. Three concentrations [25, 50 and 100 of infective juveniles (IJs) 0.2 ml-1 per adult insect] at two different temperatures (15 and 25 °C) were tested under laboratory conditions. Mortality rate was recorded after 96 h. At 15 °C, mortality rate did not exceed 50% in BCA adults, 96 h post application. At this temperature, S. feltiae was the effective species, but as the temperature increased to (25 °C), its effect didn't increase significantly. At 25 °C, H. bacteriophora caused mortality higher than 50% at the intermediate and the highest nematode concentrations (50 and 100 IJs). S. carpocapsae showed the lowest effect at both temperatures. These results suggested that EPNs might be used for the control of BCA after evaluating under field conditions. [ABSTRACT FROM AUTHOR]