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Use of chemical pesticides in agriculture harms humans, non-target organisms and environments, and causes increase resistance against chemicals. In order to develop an effective bio-pesticide against coleopterans, particularly against Agelastica alni (Coleoptera: Chrysomelidae) which is one of the serious pests of alder leaf and hazelnut, we tested the insecticidal effect of 21 Bacillus isolates against the larvae and adults of the pest. Bacillus thuringiensis var. tenebrionis-Xd3 (Btt-Xd3) showed the highest insecticidal effect based on screening tests. For toxin protein production and high sporulation of Xd3, the most suitable medium, pH and temperature conditions were determined as nutrient broth medium enriched with salts, pH 7 and 30 °C, respectively. Sporulated Btt-Xd3 in nutrient broth medium enriched with salts transferred to fermentation medium containing soybean flour, glucose and salts. After fermentation, the mixture was dried in a spray dryer, and spore count of the powder product was determined as 1.6 × 10 c.f.u. g. Moisture content, suspensibility and wettability of the formulation were determined as 8.3, 86% and 21 s, respectively. Lethal concentrations (LC) of formulated Btt-Xd3 were determined as 0.15 × 10 c.f.u. ml for larvae at laboratory conditions. LC values were also determined as 0.45 × 10 c.f.u. ml at the field condition on larval stage. Our results showed that a new bio-pesticide developed from B. thuringiensis tenebrionis (Xd3) (Btt-Xd3) may be valuable as a biological control agent for coleopteran pests.

Entomopathogenic fungi are promising microbial agents for agricultural pests, especially piercing-sucking insects. In this study, eight indigenous fungal isolates including four isolates of Metarhizium brunneum and four isolates of Beauveria bassiana were tested on Orosanga japonica Melichar (Hemiptera: Ricaniidae) in order to find an effective control agent that can be utilised for the development of oil-based fungal mycoinsecticides. In the screening test using 1 Â 10 7 spores ml À1 concentration, KTU-24 (B. bassiana) and KTU-51 (M. brunneum) had the highest lethal activity against nymphs and adults of the target pest. Also, at the highest concentration (10 9 spores ml À1 ), KTU-24 showed 92.33 and 94.88% mortality on nymphs and adults at the dose-response tests, respectively, and the KTU-51 isolate showed 100% mortality on both stages of O. japonica under laboratory conditions. With these results, KTU-24 and KTU-51 isolates were used to develop biopesticides. While the mass production of B. bassiana was carried out with liquid-state fermentation, solid-state fermentation was used for mass production of M. brunneum. Spores of both isolates were formulated in oil, and products were named as RICANICIDAL Bbas-TR61 and RICANICIDAL Met-TR61, respectively. Formulations caused over 97% mortality against nymphs and adults of O. japonica under field conditions and both formulations showed higher efficacy than commercial mycoinsecticides at 10 8 spores/ml concentration 20 days after treatment. The currents study shows that both mycoinsecticide formulations are highly promising for management of O. japonica.

Outbreaks of lesser spruce sawfly, Pristiphora abietina (Christ) (Hymenoptera: Tenthredinidae), on conifers regularly occur in Turkey and other European countries. Chemical pesticides have been used to contain outbreaks, but those may damage the forest and disturb natural enemies. To minimize the use of chemical pesticides in the management of this forest pest, we identified the entomopathogenic fungi (EPF) that naturally occur on P. abietina and tested their efficacy against the pest under laboratory and semi‐field conditions. Using morphological and molecular techniques, 13 EPF isolates were obtained from the pest and identified as Beauveria bassiana (Bals.‐Criv.) Vuill., Beauveria pseudobassiana S.A. Rehner & Humber, and Lecanicillium muscarium (Petch.) Zare & W. Gams. A laboratory screening test at 106 conidia ml−1 showed that all isolates caused 59‐100% mortality after 14 days. Further experiments were performed with the three most effective isolates, all belonging to B. bassiana. For these isolates, an increase in conidia dose increased pest mortality. Also, the ability of horizontal transmission in the pest population was shown. All three isolates were effective in killing P. abietina on spruce under semi‐field conditions. These data will contribute to the development of an integrated pest management program for P. abietina based on microbial biological control.

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European June beetle, Amphimallon solstitiale Linnaeus, 1758 (Coleoptera: Scarabaeidae) is one of the most important soilborne pests in many parts of Turkey and the world. Entomopathogenic fungi are important microbial control agents that can be used to control soilborne pests, and it is desirable to obtain them from local insect populations. The study was conducted at Karadeniz Technical University, Faculty of Science, Microbiology Laboratory in 2017. In this study, fungal pathogens of A. solstitiale were investigated to find an effective microbial control agent. Fungi were isolated from infected larvae and morphological-molecular characterization of the isolates showed that all isolates were Metarhizium flavoviride Gams & Roszypal (Deuteromycotina: Hyphomycetes). Using phylogenetic analysis and pathogenicity tests, the isolates were found to be different genotypes of M. flavoviride. All isolates gave more than 80% mortality at a concentration of 10 6 conidia/ml, with one isolate (As2) causing 96% mortality. Therefore, dose-mortality experiments were conducted with As2, and the median lethal concentration was determined to be 3.87 x 10 3 conidia/ml. This study demonstrated that M. flavoviride As2 is an effective microbial control agent that can be used for biological control of A. solstitiale.

IntroductionCorn is the largest grown cereal crop in the world with doubled grain yield per unit area compared to wheat and barley. Although corn production holds second place in Mediterranean agricultural production, there has been a sharp decline in this value due to infestation by the Mediterranean corn borer (Özcan, 2009). The Mediterranean corn borer, Sesamia nonagrioides (Lefebvre) (Lepidoptera: Noctuidae), is a major multivoltine pest of maize in Mediterranean countries (Tsitsipis, 1988;Alexandri and Tsitsipis, 1990). S. nonagrioides is a polyphagous species with a fairly wide range of host plants, including corn, sorghum, millet, rice, sugar cane, grasses, melon, asparagus, palms, and banana (Uygun and Kayapınar, 1993;Sannino et al., 2004). The population levels of this species, which has considerable potential to establish itself in an area and become abundant, may therefore depend on the abundance of these hosts (Eizaguirre and Fantinou, 2012). If insecticides are not applied, losses could rise to 100% in late and second crop production (Alexandri and Tsitsipis, 1990).Application of chemical insecticides against this harmful insect is recommended 2-3 times per growing season. However, yield losses could rise to 30% during seasons with severe insect outbreaks, even after 4-5 insecticide applications (Özcan, 2009). As well as causing significant maize crop losses, the insects reduce the nitrogen/protein content of grain by tunneling into the stem and cobs, where they are likely to interfere with the uptake of plant nutrients (Bayram, 2003). Furthermore, mycotoxigenic fungi associated with the pest often invade wound sites and can greatly depreciate the crop value (Avantaggiato et al., 2003). Although several control methods have been previously applied to this pest, damage is still pervasive. Chemical insecticides have been frequently used against it. While chemicals decrease pest population, they cause major threats to the environment and human health. Mechanical, cultural, and biological Abstract: Sesamia nonagrioides (Lep.: Noctuidae) is one of the most serious pests of corn in Turkey and other Mediterranean countries. Although various cultural, chemical, and biological methods are used to control this pest, its damage still continues in all Mediterranean countries. In this study, to find an effective bacterium that can be used as a biocontrol agent against S. nonagrioides, we isolated 15 bacteria from S. nonagrioides larvae and evaluated the larvicidal potency of all isolates on the pest. According to their morphological, physiological, biochemical, and molecular properties, the isolates were identified as Achromobacter insolitus (Sn1), Morganella morganii (Sn2), Klebsiella pneumoniae (Sn3), Citrobacter freundii (Sn4), Arthrobacter protophormiae (Sn5), Chryseobacterium indologenes (Sn6), Bacillus thuringiensis (Sn7), Bacillus safensis (Sn8), Bacillus thuringiensis (Sn9), Bacillus thuringiensis (Sn10), Klebsiella pneumoniae (Sn11), Staphylococcus sciuri (Sn12), Enterobacter kobei (Sn13), Serratia marce...