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Öğe THE CHEMICAL COMPOSITION OF CYCLOTRICHIUM ORIGANIFOLIUM ESSENTIAL OIL AND ITS INSECTICIDAL ACTIVITY AGAINST FOUR STORED-PRODUCT INSECT PESTS(Publ House Bulgarian Acad Sci, 2019) Karabörklü, Salih; Azizoğlu, Uğur; Yılmaz, Semih; Ayvaz, Abdurrahman; Akdeniz, MehmetStored-product insect pests, Acanthoscelides obtectus, Tribolium castaneum, Ephestia kuehniella and Plodia interpunctella cause serious problems all over the world and cause significant losses in agricultural crops every year. In the present study, the essential oil from Cyclotrichium origanifolium (La bill.) Manden. & Scheng. (Labiatae) was extracted, chemically characterized and tested on these insect pests. Essential oil yield was estimated to be 0.95% (v/w) with major components being pulegone (74.60%) and menthone (16.61%). Limonene (1.12%) and isopulegone (1.09%) followed the major components. Significant insecticidal activity was achieved by treating the insect pests with the essential oil. Complete mortality was obtained on A. obtectus and T. castaneum adults at the 40 mu l L-1 air concentration during 24 h exposure period. More pronounced effect was observed on the adults of E. kuehniella and P. interpunctella. Nearly complete mortality was obtained at the 8 mu l L-1 air concentration. The results indicated that C. origanifolium essential oil displayed promising effects in controlling stored-product insect pests.Öğe Cloning and expression of cry2Aa from native Bacillus thuringiensis strain SY49-1 and its insecticidal activity against Culex pipiens (Diptera: Culicidae)(Academic Press Ltd- Elsevier Science Ltd, 2017) Yılmaz, Semih; Azizoğlu, Uğur; Ayvaz, Abdurrahman; Temizgül, Rıdvan; Atcıyurt, Zehra Büşra; Karabörklü, SalihBacillus thuringiensis (Berliner) (Bt) is well known for having toxicity against pest insects because of their ability to form endospores and broad-range activity of their parasporal inclusions. In this study, a new member of cry2A gene from previously characterized native B. thuringiensis SY49-1 strain was cloned, expressed and used for its activity against Culex pipiens (Diptera: Culicidae) larvae. The sequence analysis of the cloned cry2A gene revealed that it encodes a polypeptide of 633 as residues with 99% identity to Cry2Aa protein with expected molecular weight of 70.7 kDa. Bacillus thuringiensis delta-endotoxin nomenclature committee designed our sequence as Cry2Aa18 being a new member of Bt toxins. Bioassays against last instar larvae of C pipiens indicated that Cry2Aa18 has considerable toxicity with LC50 of 630 jig ml(-1). In order to prevent the spread of infectious diseases mediated by C. pipiens, this newly characterized cry2Aa18 gene could constitute as an important biological control tool for controlling mosquito larvae living in freshwater systems and can be used as a good alternative for minimizing the use of chemicals. (C) 2017 Elsevier Ltd. All rights reserved.Öğe Effects of Bacillus thuringiensis subsp kurstaki HD1 spore-crystal mixture on the adults of egg parasitoid Trichogramma evanescens (Hymenoptera: Trichogrammatidae)(Taylor & Francis Ltd, 2015) Azizoğlu, Uğur; Yılmaz, Semih; Ayvaz, Abdurrahman; Karabörklü, SalihIn the present study, the potential hazard of Bacillus thuringiensis (Bt) kurstaki HD1 spore-crystal mixture (spore/-endotoxin) on parasitization performance and longevity of female egg parasitoid Trichogramma evanescens Westwood was evaluated. For this purpose, Bt kurstaki HD1 was incubated at 30 degrees C in T3 medium at 200 rpm for seven days. Lyophilized spore-crystal mixture (5000 mu g mL(-1)) was mixed with 50% honey solution and supplied to 0-24 h old T. evanescens adults as a nutrient to ensure the ingestion of the toxins by the parasitoids. The results indicated that spore-crystal mixture of Bacillus thuringiensis subsp. kurstaki (Btk) HD1 did not induce considerable decrease in parasitization performance and longevity of T. evanescens adults. Thus, it can be concluded that Btk HD1 products can safely be used together with egg parasitoid T. evanescens in integrated pest management system to compensate the deficiency of each control tactic alone.Öğe Expression of cry1Ab gene from a novel Bacillus thuringiensis strain SY49-1 active on pest insects(Soc Brasileira Microbiologia, 2016) Azizoğlu, Uğur; Ayvaz, Abdurrahman; Yılmaz, Semih; Karabörklü, Salih; Temizgül, RıdvanIn this study, the cry1Ab gene of previously characterized and Lepidoptera-, Diptera-, and Coleoptera-active Bacillus thuringiensis SY49-1 strain was cloned, expressed and individually tested on Ephestia kuehniella (Lepidoptera: Pyralidae) and Plodia interpunctella (Lepidoptera: Pyralidae) larvae. pET-cry1Ab plasmids were constructed by ligating the crylAb into pET28a (+) expression vector. Constructed plasmids were transferred to an Escherichia coli BL21 (DE3) strain rendered competent with CaCl2. Isopropyl beta-D-1-thiogalactopyranoside was used to induce the expression of cry1Ab in E. coli BL21(DE3), and consequently, similar to 130 kDa of Cry1Ab was obtained. Bioassay results indicated that recombinant Cry1Ab at a dose of 1000 mu g g(-1) caused 40% and 64% mortality on P. interpunctella and E. kuehniella larvae, respectively. However, the mortality rates of Bt SY49-1 strains' spore-crystal mixture at the same dose were observed to be 70% on P. interpunctella and 90% on E. kuehniella larvae. The results indicated that crylAb may be considered as a good candidate in transgenic crop production and as an alternative biocontrol agent in controlling stored product moths. (C) 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. This is an open access article under the CC BY-NC-ND licenseÖğe FUNGI ASSOCIATED WITH FREE-LIVING SOIL NEMATODES IN TURKEY(Inst Bioloska Istrazivanja Sinisa Stankovic, 2015) Karabörklü, Salih; Ayvaz, Abdurrahman; Yılmaz, Semih; Azizoğlu, UğurFree-living soil nematodes have successfully adapted world-wide to nearly all soil types from the highest to the lowest of elevations. In the current study, nematodes were isolated from soil samples and fungi associated with these free-living soil nematodes were determined. Large subunit (LSU) rDNAs of nematode-associated fungi were amplified and sequenced to construct phylogenetic trees. Nematode-associated fungi were observed in six nematode strains belonging to Acrobeloides, Steinernema and Cephalobus genera in different habitats. Malassezia and Cladosporium fungal strains indicated an association with Acrobeloides and Cephalobus nematodes, while Alternaria strains demonstrated an association with the Steinernema strain. Interactions between fungi and free-living nematodes in soil are discussed. We suggest that nematodes act as vectors for fungi.Öğe Molecular characterization of the chitinase genes of native Bacillus thuringiensis isolates and their antagonistic activity against three important phytopathogenic fungi(Springer, 2021) Azizoglu, Zehra Busra; Yilmaz, Semih; Azizoglu, Ugur; Karaborklu, Salih; Temizgul, Ridvan; Ayvaz, AbdurrahmanBacillus spp. can promote the growth of plants and reduce plant disease incidence or severity by triggering induced systemic resistance to plant pathogens. In addition, bacteria of this genus are chitinase enzyme producers. Chitinase inhibits the growth of fungi by breaking down the chitin-containing cell wall of plant pathogenic fungi. In this study, 270 native Bacillus spp., isolated from various habitats in Kayseri and Adana, Turkey, were screened by PCR for the chitinase gene and 66 of them were found to have this gene. Nine Bacillus thuringiensis (Bt) isolates showing high insecticidal activity against insect pests in our previous studies were selected from 66 isolates containing the chitinase gene. Chitinases with different molecular weights ranging from similar to 40 to 113 kDa were determined by SDS-PAGE. To determine the antagonistic effects against plant pathogenic fungi (Fusarium oxysporum f.sp. niveum, Verticillium dahliae and Aspergillus niger), a dual culture assay was used with nine native and two standard strains of Bt, and radial growth inhibition was calculated as a percentage. Of all the tested isolates, SY33.3 showed the strongest antagonistic activity and thus, can be used as an effective biological control agent against plant pathogenic fungi.Öğe Mosquitocidal Potential of Native Bacillus thuringiensis Strain SY49-1 against Disease Vector, Culex pipiens (Diptera: Culicidae)(Malaysian Soc Parasitology Tropical Medicine, 2017) Azizoğlu, Uğur; Yılmaz, Semih; Ayvaz, Abdurrahman; Karabörklü, Salih; Atcıyurt, Zehra BüşraMosquitoes are regarded as troublesome organisms worldwide due to their parasitic and pathogenic aspect causing malaria, yellow fever, dengue, West Nile and filariasis. Bacillus thuringiensis (Bt) products have effectively been used for decades in controlling the mosquito mediated diseases and also decreasing the chemical input into the environment. In the present study, biocontrol potential of previously characterized Bt SY49-1 strain was investigated on Culex pipiens larvae. Fourth instars of C. pipiens were subjected to spore/delta-endotoxins (50, 100, 250 and 500 mu g mL(-1)) of Bt SY49-1 strain, carrying cry genes active against Lepidoptera, Diptera, Coleoptera and Nematodes. The spore/delta-endotoxin mixture caused 100% mortality on the larvae at the dose of 500 mu g mL(-1). PCR results indicated that Bt SY49-1 harbors Lepidopter-Dipter specific cry2A gene as well as Lepidopter specific cry1Ab, cry1Aa/Ad, cry1C, cry9A, cry9C, Lepidopter-Dipter-Coleopter specific cry1B, and Nematode specific cry5 gene. Results indicated the potential usage of Bt SY49-1 in preventing the breeding of C. pipiens and the spread of diseases resulting therefrom.Öğe Native entomopathogenic nematodes isolated from Turkey and their effectiveness on pine processionary moth, Thaumetopoea wilkinsoni Tams(Taylor & Francis Ltd, 2015) Karabörklü, Salih; Ayvaz, Abdurrahman; Yılmaz, Semih; Azizoğlu, Uğur; Akbulut, MikailTwo native entomopathogenic nematodes were isolated from soil samples in Eastern Mediterranean region of Turkey and characterized based on 28S rDNA region. BLASTN homology and phylogenetic analysis of SK17 and SK-71 isolates indicated 98% and 99% identity to Steinernema affine and Steinernema feltiae, respectively. The results were constructed by neighbour-joining and bootstrap tree methods. Efficacy of S. affine (SK-17 strain) and S. feltiae (SK-71 strain) was tested against the larvae of pine processionary moth, Thaumetopoea wilkinsoni Tams, and remarkable mortality rates were obtained. Both strains caused complete mortality upon application of 500 IJs in foliar tests. However, the same strains caused 30% and 33% mortality at 80 IJs/cm(2) in soil applications. It was concluded that these native strains could be considered as potential biocontrol agents for reducing the damage caused by T. wilkinsoni larvae.Öğe PHYLOGENETIC RELATIONSHIPS OF INSECT-ASSOCIATED FREE-LIVING RHABDITID NEMATODES FROM EASTERN MEDITERRANEAN REGION OF TURKEY(Corvinus Univ Budapest, 2016) Azizoğlu, Uğur; Karabörklü, Salih; Ayvaz, Abdurrahman; Yılmaz, SemihFree-living nematodes play an important role in nutrient cycling. The study was designed to characterize insect-associated free-living soil nematodes in Rhabditida order from Eastern Mediterranean region of Turkey using their 28S rDNA sequences and phylogenetic analysis. A total of 105 soil samples were taken from different habitats. Galleria baiting technique was used to obtain free-living nematodes. The nematodes were harvested from cadavers of last instar Galleria mellonella larvaeafter trapping process. Free-living soil nematodes were detected in 14 soil samples (13.3%). PCR products obtained from 28S rDNA of isolates were sequenced and phylogenetic trees created. BLASTN homology searches and phylogenetic tree results constructed by Neighbour Joining and Bootstrap Tree methods. Results showed that these insect-associated isolates were determined as species belonging to Rhabditidae (Rhabditis terricola and Mesorhabditis sp.), Chambersiellidae (Macrolaimus sp.) and Cephalobidae (Cephalobus sp., Pseudacrobeles sp. and Acrobeloides sp.) families in Rhabditida. Free-living nematodes interact with many arthropods and other invertebrate species. These interactions are also important for their use in biological control program. In this study, these interactions between free-living nematode-insect,-arthropod and-invertebrate are discussed.