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Made available in DSpace on 2022-05-01T13:11:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-01-01 Immature endoparasitoids develop inside their hosts. Consequently, endoparasitoids need to circumvent the action of the immune system and reprogram the physiology of their hosts to develop successfully. For this, parasitoids release host regulation-related molecules into their host’s hemolymph produced by the parasitoid itself or expressed in specific host cells infected by parasitoid symbiotic viruses. In addition to their roles in host regulation, these molecules may also present biotechnological potentials, such as for insecticidal purposes in crop protection. We performed a survey for the biotechnological potential of compounds present in the hemolymph serum with and without circulating cell contents of Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae) parasitized by Cotesia flavipes Cameron (Hymenoptera: Braconidae) as insecticides in feeding assays. Hemolymph serum from D. saccharalis larvae at 6 days after the start of the parasitism with and without circulating cell contents were collected and spread over artificial diet or over sugarcane leaves for feeding assays with D. saccharalis neonates. Hemolymph serum with or without circulating cell contents from non-parasitized D. saccharalis larvae at the same age were used as controls. Subsequently, hemolymph serum plus circulating cell contents was fractioned using molecular filters and fractions with different molecular weight range were used for feeding assays with D. saccharalis neonates. Feeding larvae with leaf disks amended with hemolymph serum plus circulating cell contents from parasitized hosts resulted in an increase of ca. 30% in the mortality of D. saccharalis neonates. After fractioning hemolymph serum plus circulating cell contents, feeding assays with the >100 or 3–10 kDa fractions did not result in the previously observed increase in larval mortality, but resulted in a reduction of leaf consumption by neonates. Finally, we selected a parasitism-specific protein band observed in the hemolymph >100 kDa fraction for mass spectrometry identification. This parasitism-specific protein was similar to hymenopteran apolipophorins-I. We conclude that there is an insecticidal potential in the hemolymph serum plus circulating cell contents of D. saccharalis larvae parasitized by C. flavipes and further investigations will be performed to identify, characterize, and uncover the biotechnological application of these molecules. School of Agricultural and Veterinarian Science São Paulo State University (UNESP), 14.884-900, SP University of Franca (UNIFRAN), 14.870-370, SP School of Agricultural and Veterinarian Science São Paulo State University (UNESP), 14.884-900, SP

Made available in DSpace on 2021-06-25T10:56:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-06-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Several secondary metabolites are associated with plant resistance against herbivores. Cassava genotypes present a wide variety of metabolites with insecticidal potential, but little is known about the identity of these compounds. The present work was conducted for the identification of insecticidal molecules present in cassava genotypes. To this purpose, we firstly evaluated the development of the generalist herbivore Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae) fed with leaves from six cassava genotypes (IAC-14, IAC-90, IAC-12, IAC-Caapora, Baianinha and MEcu 72). Following bioassays, we measured the levels of two anti-herbivory related groups of compounds (phenolics and steroidal saponins) in all genotypes using colorimetric methods. The metabolic fingerprinting (GC–MS) of three contrasting cassava genotypes selected by their biological interferences over S. frugiperda was performed. The most unsuitable nutritional indices were observed for larvae fed with MEcu 72. Lower reproductive indices were observed for adults in which larval stages were fed with Baianinha or MEcu 72. Steroidal saponin content was similar in all genotypes, but phenolic content was 25% higher in MEcu 72. GC–MS metabolite fingerprinting of MEcu 72, Baianinha and IAC-Caapora resulted in the annotation of 53 metabolites in which 20 presented different relative abundance among the evaluated genotypes. Molecules such as myo-inositol-2-monophosphate, p-coumaric acid, chlorogenic acid, p-hydroxybenzoic acid, octadecadienoic acid and n-hexacosane were more abundant in MEcu 72 or Baianinha than in IAC-Caapora. The possible roles of these molecules in the development of S. frugiperda are discussed. School of Agricultural and Veterinarian Sciences São Paulo State University (UNESP) Institute of Biosciences São Paulo State University (UNESP) Institute of Chemistry São Paulo State University (UNESP) Departamento de Ciências da Produção Agrícola Setor de Fitossanidade Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Via de Acesso Prof. Paulo Donato Castellane s/n School of Agricultural and Veterinarian Sciences São Paulo State University (UNESP) Institute of Biosciences São Paulo State University (UNESP) Institute of Chemistry São Paulo State University (UNESP) Departamento de Ciências da Produção Agrícola Setor de Fitossanidade Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Via de Acesso Prof. Paulo Donato Castellane s/n CAPES: Finance Code 001

Made available in DSpace on 2019-10-06T17:12:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-09-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Biological control using entomopathogens and natural enemies is an ecofriendly method for pest management in agriculture. Biological control agents often can be simultaneously employed and compatibility between agents may improve pest suppression. We investigated the influence of the entomopathogen Bacillus thuringiensis (Bt) on the immune system of the sugarcane borer Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) to determine if such changes impact parasitization by Cotesia flavipes Cameron, 1891 (Hymenoptera: Braconidae). The immune response of surviving D. saccharalis larvae fed with an LC25 dosage of a Bt-based biopesticide (Dipel®) was analyzed (total hemocyte count, hemocyte adhesion, and activities of phenoloxidase and lysozyme). Furthermore, the suitability of surviving Bt-fed larvae as hosts for C. flavipes was assessed by measuring parasitoid attributes such as number and size of teratocytes, weight of pupae, length of adult female tibia and number of emerged adults. Total hemocyte count, but not hemocyte adhesion, total protein content and phenoloxidase activity increased in the hemolymph of non-parasitized Bt-fed larvae (Bt-NP) compared to control larvae (NBt-NP). Lysozyme activity increased only after parasitization without Bt exposure (NBt-P). After parasitization, the immunological parameters activated in Bt-NP larvae decreased to levels at or below those observed in control larvae, showing that C. flavipes can regulate the activated immune response of Bt-fed larvae. The development of C. flavipes was not impaired in Bt-fed larval hosts (Bt-P); no changes were observed for teratocyte size, weight of pupal mass, length of hind tibia and number of adults emerged. São Paulo State University (Unesp) School of Agricultural and Veterinarian Sciences São Paulo State University (Unesp) School of Agricultural and Veterinarian Sciences

Made available in DSpace on 2018-12-11T17:32:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-05-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The giant cicada, Quesada gigas (Olivier) (Hemiptera: Cicadidae), is an important coffee pest and information about the behavior and reproduction of this species, e.g. emergence, senescence and ovarian maturation status, can be valuable to understand giant cicada ecology and to improve the use of a sound trap as a control method. A great number of Q. gigas adult males and females was captured using a sound trap and a protandrous type of emergence possibly associated with chorus centers formation was observed. All giant cicadas collected until 14–15 days after the beginning of male emergence (DAME) had immature ovaries at two different years of evaluation. On the other hand, the majority of cicadas collected from 20 until 48 DAME had mature ovaries with visible chorionated oocytes. Despite the use of the sound trap to collect insects for ecological studies, we believe that next generations of Q. gigas can be reduced by using this sound trap to hinder the formation of giant cicada chorus centers, to reduce male availability to copulate with females and to reduce the number of females to oviposit in coffee plants. School of Agricultural and Veterinarian Sciences São Paulo State University (Unesp) Departamento de Fitossanidade, Via de Acesso Prof. Paulo Donato Castellane s/n School of Agricultural and Veterinarian Sciences São Paulo State University (Unesp) FAPESP: 14/06137-0