A new entomopathogenic nematode species for Turkey, Heterorhabditis megidis Poinar, Jackson & Klein 1987 (Rhabditida: Heterorhabditidae)

During a survey on the occurrence of entomopathogenic nematodes (EPNs) in the Eastern Black Sea region of Turkey, a heterorhabditid species was isolated using the Galleria-baiting technique. Based on morphology and morphometrics, the isolate was identified as Heterorhabditis megidis. Sequences of the ITS region of its rDNA confirmed this identification. The species is recorded for the first time from Turkey. A more intensive survey to determine the distribution of this species, covering all parts of the Black Sea region of Turkey, is currently underway

Screening antibacterial activity of entomopathogenic bacteria isolated from pests of hazelnut

Demirbag, Zihni/0000-0001-5487-1977WOS: 000320373500004Thirty-seven entomopathogenic bacteria isolated from six common pests of hazelnut in the Black Sea Region of Turkey have been screened for their potential of antibacterial substance production against indicator bacteria by the agar spot assay and well diffusion assay. Results indicated that 13.5% of entomopathogenic bacteria, Pseudomonas fluorescens (Pf-Xd1), Bacillus polymyxa (Bp-Ar2), Bacillus thuringiensis (Bt-Bn1), Serratia marcescens (Sm-Mm3) and Pseudomonas flourescens (Pf-Aa4) isolated from pests of Xyleborus dispar, Anoplus roboris, Balaninus nucum, Melolontha melolontha and Agelastica alni, respectively, showed significant levels of inhibitor activities against indicator bacteria. Well diffusion assay showed that supernatants of Bp-Ar2, Bt-Bn1 and Sm-Mm3 have antibacterial activity, whereas Pf-Xd1 and Pf-Aa4 did not show any activity. Furthermore, the antibacterial activity of the substance produced by the Bp-Ar2 has a narrow spectrum, whereas those of Bt-Bn1 and Sm-Mm3 exhibit broad spectrum. The production of these antibacterial substances were similarly determined at early logarithmic phase in the growth cycle of three bacteria and continued until the beginning of the stationary phase as primer metabolite. In addition, optimal pH (at 7-9 forBt-Bn1 and 5-9 forSm-Mm3), medium (Muller Hinton broth forBt-Bn1 and Luria Bertani broth forSm-Mm3), temperature (25A degrees C for Bt-Bn1 and Sm-Mm3) and production time (24h forBt-Bn1 and 72h forSm-Mm3) of these substances were determined. Our results demonstrate that entomopathogenic bacteria are a potential source of antibacterial substances

Genetic variability of Beauveria bassiana and Metarhizium anisopliae var. anisopliae isolates obtained from the Eastern Black Sea region of Turkey

Beauveria bassiana (Balsamo) Vuillemin and Metarhizium anisopliae var. anisopliae (Metschnikoff) Sorokin are the most common entomopathogenic fungi used in microbial control programs all over the world. Assessments of the genetic variability of these 2 important species are useful for the development of effective biocontrol strategies and for evaluating the impact of artificial epizootics. In this study, the genetic diversity of 13 B. bassiana and 33 M. anisopliae var. anisopliae strains isolated from the hazelnut-growing region of Turkey was determined by using the amplified fragment length polymorphism (AFLP) and alpha- and beta-isoenzyme analyses. Cluster analysis of AFLP data clearly separated both B. bassiana and M. anisopliae var. anisopliae strains into 3 and 4 different groups, respectively. While alpha- and beta-esterase banding patterns clearly separated M. anisopliae var. anisopliae strains, it did not give enough information about B. bassiana strains. We also assessed the growing ability of all isolates at different temperatures (8, 16, 25, and 37 degrees C) and UV exposures (30 and 60 min), and virulence against Tenebrio molitor. These results indicated that there is a significant variability within the B. bassiana and M. anisopliae var. anisopliae populations in this region. Although the diversity of B. bassiana isolates is associated with geographic location, it is not associated with habitat type. There is also no association amongst B. bassiana isolates in terms of the ability to grow at different temperatures and UV exposures, or virulence against T molitor. The diversity of M. anisopliae var. anisopliae strains is neither associated with habitat type nor geographic location, and there is no association amongst M. anisopliae var. anisopliae strains in terms of the ability to grow at different temperatures (except for 16 degrees C) and UV exposure, or virulence against T. molitor. The data presented here might be useful for controlling some hazelnut pests in this region

Efficacy of native entomopathogenic nematodes from Turkey against the alder leaf beetle, Agelastica alni L. (Coleoptera: Chrysomelidae), under laboratory conditions

Abstract The alder leaf beetle, Agelastica alni L. (Coleoptera: Chrysomelidae), is one of the most defoliator pests of oak and alder trees. In the present study, the efficacies of three native strains of entomopathogenic nematodes, Heterorhabditis bacteriophora (ZET35), Steinernema feltiae (ZET31), and Steinernema websteri (AS-1), were tested against pre-pupae and adults of A. alni. Experiments were conducted by four concentrations under laboratory conditions in 2015. Four different temperature regimes were tested at concentration of 1000 infective juveniles (IJs)/ml under laboratory conditions. It was observed that pre-pupae were more sensitive than adults in all tests. Based on screening tests, S. websteri was the most effective isolate on both pre-pupae and adults of A. alni at concentration of 1000 IJs/ml with 79.17 and 71.11% mortality, respectively. It caused the highest mortality values at all temperatures, except for 30 °C against pre-pupae and adults. Results of the present study suggested that S. websteri and H. bacteriophora had significant potentials against A. alni

Isolation, characterization and virulence of entomopathogenic fungi from Gryllotalpa gryllotalpa (Orthoptera: Gryllotalpidae)

WOS: 000374579300005Mole crickets are significant pests of turf, vegetable and some tree seedlings worldwide, and it is costly to control them. In this study, we obtained 15 fungal isolates from Gryllotalpa gryllotalpa L. (Orthoptera: Gryllotalpidae) and compared the efficacy of these isolates against this pest with the aim of identifying their biocontrol potential. The fungal isolates were identified based on their morphological and molecular characteristics, using ITS, EF1-alpha, Bloc, RPB1, RPB2 and beta-Tubulin gene sequencing. Consequently, the isolates were identified as Beauveria bassiana (Balsamo) Vuillemin (Gg-1), Clonostachys sp. (Gg-2, Gg-3, Gg-5, Gg-6, Gg-8 and Gg-13), Bionectria sp. (Gg-4), Metarhizium anisopliae (Metschnikoff) Sorokin (Gg-7, Gg-12 and Gg-14), Clonostachys rogersoniana (Schroers) (Gg-9 and Gg-15), Myriodontium sp. (Gg-10) and Myriodontium keratinophilum (Samson and Polon.) (Gg-11). These isolates caused mortalities ranging from 0 to 87 %, with the most virulent fungus being M. anisopliae Gg-12, which caused 87 % mortality within 15 days post inoculation using a conidial concentration of 1 x 10(7) conidia ml(-1). Concentration-response test was conducted to determine the LC50 value of M. anisopliae Gg-12, and it was calculated as 1.069 x 10(6) conidia ml(-1). As a result, M. anisopliae Gg-12 can be further investigated in terms of controlling mole crickets.Karadeniz Technical University, Scientific Research Projects DivisionKaradeniz Teknik University [KTU 8625]We would like to thank Dr. Richard Humber for his kind help with the morphological characterization of fungi, and to acknowledge with gratitude the input and insight of Tariq M. Butt for developing the discussion section and providing recommendations for this manuscript. Also, we would like to thank Ozkan Gorgulu for his advice on statistical analysis. This study was supported by Karadeniz Technical University, Scientific Research Projects Division (Project Number: KTU 8625)

Genome sequence analysis of a Helicoverpa armigera single nucleopolyhedrovirus (HearNPV-TR) isolated from Heliothis peltigera in Turkey.

The entire genome of Helicoverpa armigera single nucleopolyhedrovirus (HearNPV-TR) was sequenced, and compared to genomes of other existing isolates. HearNPV-TR genome is 130.691 base pairs with a 38.9% G+C content and has 137 open reading frames (ORFs) of ≥ 150 nucleotides. Five homologous repeated sequences (hrs) and two baculovirus repeated ORFs (bro-a and bro-b) were identified. Phylogenetic analysis showed that HearNPV-TR is closer to HaSNPV-C1, HaSNPV-G4, HaSNPV-AU and HasNPV. However, there are significant differences in hr3, hr5 regions and in bro-a gene. Pairwise Kimura-2 parameter analysis of 38 core genes sequences of HearNPV-TR and other Helicoverpa NPVs showed that the genetic distances for these sequences were below 0.015 substitutions/site. Genomic differences as revealed by restriction profiles indicated that hr3, hr5 regions and bro-a gene may play a role in the virulence of HearNPV-TR

Investigating internal bacteria of Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) larvae and some Bacillus strains as biocontrol agents

WOS: 000328624300012Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) is one of the most destructive pests of several vegetables and fruits worldwide. In spite of various control methods, this pest has still continued to cause significant damage. In this study, the culturable bacterial flora of S. littoralis was determined. New isolates from S. littoralis, as well as 12 different Bacillus isolates belong to 5 species that were previously isolated from different pests, were tested on S. littoralis larvae. In total, 9 bacteria were characterized based on their morphological, biochemical, physiological, and molecular characteristics. The bacterial flora of S. littoralis was determined as Flavobacterium sp. (SL1), Klebsiella pneumonia (SL2), Enterobacter sp. (SL3), Enterobacter sp. (SL4), Klebsiella sp. (SL5), Serratia marcescens (SL6), Pseudomonas aeruginosa (SL7), Acinetobacter baumannii (SL8), and Staphylococcus sp. (SL9). The insecticidal activity tests were performed on the third-instar larvae of S. littoralis. SL1 and SL5 from S. littoralis caused the highest mortalities with 67% and 77%, respectively. Among previously isolated Bacillus isolates, Bacillus thuringiensis subsp. kurstaki (MnD) and B. thuringiensis subsp. kurstaki (BnBt) were found to be the most effective, causing 100% mortality within 10 days after treatment. A concentration-response test was conducted with these isolates and it was found that the isolate MnD was more effective than BnBt. Therefore, further bioassay experiments were conducted with the isolate MnD and results were discussed with respect to the biocontrol potential of the bacterial isolates

Determination of fungal pathogens of Hypera postica (Gyllenhall) (Coleoptera: Curculionidae): isolation, characterization, and susceptibility

WOS: 000436823500002Background: Fungal pathogens of Hypera postica (Gyllenhall) (Coleoptera: Curculionidae) were collected from the vicinities of Adana and Igdir in Turkey. The pathogenicity of the fungal isolates against the pest were investigated. According to morphologic (colony morphology, spore shape) and molecular (sequences of ITS1-5.8S ITS2 region and EF1-a, Bloc, and RPB1 genes) characterizations, the isolates were identified as Beauveria bassiana (HpI-2, HpI-6, HpI-7, HpI-10, HpA-3, HpA-4, HpA-5) and Beauveria pseudobassiana (HpI-4). All these strains were isolated from H. postica for the first time. In order to determine pathogenesis of all isolates on the target pest, bioassays were conducted against larvae and adults, as screening of (1 x 10(7) conidia/ml) and dose-response (1 x 10(5), 1x10(6), 1 x 10(7), 1x10(8), conidia/ml), under laboratory conditions. The fungal isolates, closely related to each other, yielded significantly varied mortalities on larvae and adults. H. postica larvae were found more susceptible than adults to the fungal isolates in all tests. The highest mortality rates (100 and 98%) for larvae and adults, respectively, were obtained by B. bassiana strain HpA-5 within 14 days at 1 x 10(8) conidia/ml concentration. The median lethal concentration (LD50) of HpA-5 required to kill the larvae and adults of H. postica at concentrations of 2.37 x 10(4) and 1.4 x 10(5) conidia/ml, respectively. These results are promising; therefore, the B. bassiana strain HpA-5 can potentially be used against H. postica