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The pine processionary moth Thaumetopoea pityocampa Den. and Schiff. (Lep., Thaumetopoeidae) is one of the most harmful insect pests for pine species in Mediterranean countries including Turkey. Two Bacillus thuringiensis isolates obtained from T. pityocampa were identified and characterized in terms of crystal shape using electron microscopy, SDS-PAGE analysis, cry gene contents, H-serotype and insecticidal activity. Examination by a scanning electron microscope showed that Tp6 and Tp14 isolates have flat square and bipyramidal crystal shapes, respectively. PCR analysis showed that Tp6 contains cry3 gene and Tp14 isolate contains cry1 and cry2 genes. On the other hand, the presence of Cry3 and Cry1 proteins were confirmed by observation of approximately 65- and 130-kDa proteins by SDS-PAGE in Tp6 and Tp14 isolates, respectively. According to H-serotype results, these isolates were identified as Bacillus thuringiensis ssp. morrisoni (H8a8b). Toxicity tests were performed against six insect species belonging to Lepidoptera and Coleoptera. The highest insecticidal activity was 100% for Tp6 isolate on larvae of Agelastica alni and Leptinotarsa decemlineata and 100% for Tp14 isolate on larvae of Malacosoma neustria. Our results indicate that isolates Tp6 and Tp14 may be valuable biological control agents for various coleopteran and lepidopteran pests. [ABSTRACT FROM AUTHOR]

A broad survey of the fall webworm (Lepidoptera: Erebidae) populations in agricultural and forested areas in the Central Black Sea Region of Turkey led to the detection of a granulovirus (GV). Hyphantria cunea granulovirus (HycuGV)-Hc1 isolate was characterized and tested against third instar larvae of H. cunea. Electron microscopy confirmed typical GV morphology with ovoid granules of approximately 368 ±  16 nm × 201 ±  19 nm. Each granule contained a single rod-shaped virion with a mean size of 43 ± 12 nm × 250 ± 12 nm. The genome was analyzed by restriction endonuclease and estimated to be ∼112 kb. Partial sequencing of the granulin (gran), late expression factor-8 (lef-8) and late expression factor-9 (lef-9) genes also confirmed the identity of the virus as HycuGV. A phylogenetic analysis based on these conserved genes, HycuGV-Hc1 grouped together with the previous HycuGV isolate (A5-1) and Estigmene acrea granulovirus (EsacGV) isolate from the same family. The LC50 of HycuGV-Hc1 was 2.6 × 104 occlusion bodies (OBs/ml). Pot experiments, under field conditions, showed significant differences between virus treated and control groups. This is the first study to describe a novel Turkish HycuGV-Hc1 isolate, and preliminary data suggests that the virus has a significant potential as an effective biopesticide for control of H. cunea. [ABSTRACT FROM AUTHOR]

With the aim of developing better procedures for rearing the microtype tachinid fly Pales pavida (Meigen), we performed ecological studies in the laboratory using the natural host Mythimna separata (Walker), investigating larval development, mating behaviour, individual oviposition patterns and relationships between parasitisation and number of eggs ingested (NEI) per host. The host instar at the time of parasitoid egg ingestion significantly affected the development time of the immature parasitoid: development took longer when the hosts ingested eggs when at the fifth instar than at the sixth (last) instar. There was no difficulty obtaining mated females in the laboratory when day 0-1 female flies were kept with day 2-4 males. Mean lifetime fecundity was 5805 ± 568 eggs per female. Daily rates of oviposition by individual females varied widely; the greatest number of eggs laid in a day was exactly 1700. When the NEI by day 1 fifth instars or day 0 or 3 last instars was 1, 3, 6 or 10, the parasitisation percentage tended to increase with increasing NEI, although it did not differ significantly between NEI 6 and 10. Therefore, the percentage adult emergence per egg ingested decreased from NEI 6 to 10, particularly in the case of last instars. Using day 0 last instars, with six eggs ingested per host, should increase parasitisation rates and shorten the development time of the parasitoid for rearing. [ABSTRACT FROM AUTHOR]

In this study,Lymantria dispar disparlarvae, collected from three different localities in Turkey, were examined for the presence of inclusion bodies under phase contrast and electron microscopes. Inclusion bodies from infected larvae were subjected to polymerase chain reaction using the conserved primers forpolyhedrin(polh),late expression factor8 (lef-8) andlate expression factor9 (lef-9) genes. Sequence analysis confirmed that larvae collected from the three different localities contained multiple nucleopolyhedrosis viruses (MNPVs). These isolates were designated LdMNPV-T1, LdMNPV-T2 and LdMNPV-T3. Phylogenetic analyses of these isolates were performed using target genespolh,lef-8 andlef-9. Restriction endonuclease analysis of the three geographic isolates withEcoRI andPstI enzymes demonstrated some differences existed among the isolates. According to theEcoRI profile, the mean estimated size for the complete genome of each isolate (LdMNPV-T1, LdMNPV-T2 and LdMNPV-T3) was calculated to be approximately 170, 153 and 170 kb,respectively. Insecticidal activities of each isolate were tested onL. d. disparlarvae using four different viral concentrations between 103and 106 OBs/ml. Results showed that the mortalities for LdMNPV-T1, -T2 and -T3 ranged between 13–53%, 47–100% and 46–93%, respectively. The LC50and LC95values of LdMNPV-T2 were not significantly different from the respective corresponding values of the other two isolates. However, isolate LdMNPV-T2 killed larvae with a LC50value that was lower than the other two isolates. Our results suggested there are promising LdMNPV isolates in Turkey that can be used for microbial control ofL. d. disparlarvae. [ABSTRACT FROM AUTHOR]

According to the present research trend and legislative framework of the major world regions fostering the development and use of low-risk biocidal and plant protection products for Integrated Pest Management, the discovery of new entomopathogenic bacterial species and isolates bearing insecticidal traits against novel targets is needed in the near future. In this study, the oral insecticidal activity of bacteria isolated from septicaemicGalleria mellonellalarvae was assessed against different insect pests of agricultural, forest and medical-veterinary importance, including Lepidoptera (Lymantria disparandMalacosoma neustria) and Diptera (Musca domesticaandCeratitis capitata). This led to the identification of new entomopathogenic bacterial isolates belonging to different species includingAlcaligenes aquatilis, Alcaligenes faecalis, Enterococcus mundtii, Pseudomonas protegens, Serratia nematodiphila, Serratia marcescensandStenotrophomonas maltophilia. The majority of these isolates were toxic to gypsy mothL. disparand, more moderately, to lackey mothM. neustrialarvae. Variable degrees of virulence were observed on fly species. While the insecticidal action of some of these species was previously observed, we report for the first time the insecticidal properties of specific strains against a wider target range. [ABSTRACT FROM PUBLISHER]

A biopesticide with a mixture of entomopathogenic microbial agents was studied for improvements in efficacy. Recently developed liquid fermentation techniques were used to produce blastospores ofBeauveria bassiana(Balsamo) Vuillemin strain GHA (Bb), which were mixed with traditional fermentation ofBacillus thuringiensisBerlinerkurstaki(Bt) spores and crystals. Based on a dosage response bioassay usingTrichoplusia ni(Hübner) neonates exposed to treated leaf disks, the LC50values were determined to be 3.85 × 107spores mL−1for the unformulatedBtand 3.58 × 107blastospores mL−1for the unformulatedBb. Using the same bioassay conditions, mixtures ofBt:Bbat ratios of 1:0, 0.75:0.25. 0.5:0.5, 0.25:0.75, and 0:1 indicated that the greatest mortality was caused by the 0.5:0.5 mixture ratio of the microbial agents. Based on these results, the 0.5:0.5 mixture was formulated as a dry powder by spray drying and applied to field-grown cabbage for comparison with commercialBtandBbproducts. Overall, the mixed agent treatment caused equal or greater mortality of exposed insects when compared with commercial products. The insecticidal interaction was determined to be synergistic when combining these two microbial agents into a single product, providing greater mortality of target insects. Assuming similar fermentation costs, the combined treatment could provide improved efficacy without increasing production costs. These benefits support the concept of formulating mixed microbial agents as an environmentally friendly pest control tool. [ABSTRACT FROM PUBLISHER]

We determined the virulence ofBeauveria bassiana,Metarhizium anisopliae,Isaria fumosoroseusandLecanicilium lecaniiagainst larvae ofChilo suppressalisWalker by bioassay and evaluated several enzymatic and non-enzymatic components. LC50values of the entomopathogenic fungi revealed 90, 32, 45,000, 4600, 42,000 and 1,540,000 spores/larva for isolates BB1–BB3 ofB. bassiana,I. fumosoroseus,M. anisopliaeandL. lecanii, respectively. Isolate BB3 andI. fumosoroseushad the highest amounts of total protein and hydrophobin and isolates BB3 andM. anisopliaeshowed the highest activities of lipases and chitinases. In case of proteases, the highest activities were observed for Pr1 of BB1 and Pr2 ofL. lecanii. The highest general esterase activities were obtained inI. fumosoroseusand BB1 when 1-naphtyl acetate and 2-naphtyl acetate were used as substrates. The highest activity of glutathioneS-transferase (GST) was observed inI. fumosoroseusby using both reagents but BB1 demonstrated the highest activities of alkaline phosphatase and acid phosphatase. Clustering of the fungi using biochemical enzymes revealed BB2 and BB3 as a separate group of entomopathogenic fungi. In another group,I. fumosoroseusandL. lecaniihad the most similarity and were separated from BB1 andM. anisopliae. The fungi exhibited different virulence on larvae ofC. suppressalisby producing adhering protein and extracellular enzymes. Overall, results of the bioassays and clustering based on enzymatic activities revealed that isolate BB2 was the most effective fungus against larvae ofC. suppressalis. [ABSTRACT FROM PUBLISHER]