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Metcalfa pruinosa (Say) is one of the important harmful insect species of the coastal areas of Eastern Black Sea Region. This insect poses a danger by feeding on the juices of hundreds of plants in the region. This study was designed to create a fight strategy against M.pruinosa, which has posed an intense danger in Artvin - Kemalpasa in recent years, and the effect of Spruzit Neu and Dipel biopesticides on the nymphs and adults of the insect was investigated, and the applicability of these biopesticides was revealed. The study was conducted in the summer season of 2016 when the nymphs and adults of the insect are abundant in the region. In in vitro conditions, the Spruzit Neu (Pyrethrum) and Dipel DF (Bacillu thuringiensis) biopesticides were sprayed at different doses (DiPel® DF BT 100gr / 100lt, Dipel® DF BT 300gr / 100lt, Dipel® DF BT 500gr / 100lt ve Spruzit® Neu) on the nymphs and adults of the insect. The adults and nymphs were checked with 2-day intervals, and the results were assessed according to the One-Way Variance Analysis (ANOVA) and the Duncan Test. It was determined that the most effective applications for the nymphs were Dipel DF 300gr/100lt and 500gr/100lt. It was also determined that the most effective applications for the adult individuals were Spruzit Neu 600ml/100lt and Dipel DF 500gr/100lt doses. The highest death rates in the nymphs were determined in Spruzit Neu 600ml/100lt dose as 72,5%; and in Dipel DF dose as 80%. These rates were determined in Pyrethrum 600 ml/100lt dose as 78%, and in Dipel DF 500 gr/100lt dose as 75%. As a conclusion, it was determined that both biopesticides are influential on the nymphs and adults of M.pruinosa. However, it was also determined that the fight will be more influential in the nymph period of the insect.

Submitted by HELVIO CAMPOY COSTA JUNIOR null (helviocampoy@hotmail.com) on 2018-01-24T20:17:31Z No. of bitstreams: 1 Dissertação_Helvio_Campoy_Costa_Junior.pdf: 901555 bytes, checksum: c6e5d61c52e8062ad3355807212bd08a (MD5) Approved for entry into archive by Karina Gimenes Fernandes null (karinagi@fcav.unesp.br) on 2018-01-26T10:44:07Z (GMT) No. of bitstreams: 1 costajunior_hc_me_jabo.pdf: 901532 bytes, checksum: 2d8a2d766da611d354e51bed9eacd12d (MD5) Made available in DSpace on 2018-01-26T10:44:07Z (GMT). No. of bitstreams: 1 costajunior_hc_me_jabo.pdf: 901532 bytes, checksum: 2d8a2d766da611d354e51bed9eacd12d (MD5) Previous issue date: 2017-11-30 O objetivo desta pesquisa foi avaliar o efeito subletal causado pelo bioinseticida Dipel em lagartas de Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae). Bacillus thuringiensis (Bt) é um entomopatógeno amplamente utilizado no controle de pragas, porém pouco se sabe sobre seus efeitos em concentrações subletais, que podem ocorrer em campo devido à diferença na distribuição da calda de aplicação ao longo do dossel das culturas ou diferenças na concentração da expressão de toxinas Bt em tecidos de plantas geneticamente modificada. Neste estudo foi utilizado o bioinseticida Dipel na formulação SC, nas concentrações de 3,67 x 106; 6,85 x 106; 6,85 x 107; 1,37 x 108 e 6,85 X 108 esporos.mL-1, além do tratamento controle, no qual recebeu aplicação de apenas água deionizada para instalação do bioensaio para estimativa das concentrações subletais. Para cada concentração foram utilizadas dezesseis lagartas e três repeticões. A análise de Probit, foi utilizada para estimar as concentrações letais; CL10, CL15, CL20 e CL25, que são consideradas concentrações subletais por apresentarem mortalidade abaixo de 25%. Posteriormente, foi instalado outro bioensaio para avaliar alguns parâmetros biológicos, tais como: período de duração da fase larval, peso de indivíduos na fase larval, peso de indivíduos na fase de pupa e razão sexual. Em todas as concentrações foi observado um aumento significativo no período larval, com destaque para CL25 que apresentou o maior período, chegando a mais de 36 dias. Também foram observadas diferenças significativas no peso de lagartas, peso de pupas. Apenas a concentração CL10 não apresentou diferença significativa em relação ao tratamento controle no parâmetro peso de pupas. Concentrações subletais de Bt são capazes de interferir no desenvolvimento de indivíduos de H. armigera, podendo contribuir para reduzir os prejuízos causados por essa praga. The objective of this research was to evaluate the sublethal effect caused by Dipel bioinsecticide on Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) caterpillars. Bacillus thuringiensis (Bt) is an entomopathogen widely used in pest control, but little is known about its effects on sublethal concentrations, which may occur in the field due to the difference in distribution of the application along the canopy of the crops or differences in concentration expression of Bt toxins in genetically modified plant tissues. In this study, the Dipel bioinsecticide was used in the SC formulation, at concentrations of 3.67 x 106; 6.85 x 106; 6.85 x 107; 1.37 x 108 and 6.85 X 108 spores.mL-1, in addition to the control treatment, in which it received application of only deionized water to install the bioassay to estimate the sublethal concentrations. Sixteen caterpillars and three replicates were used for each concentration. Probit analysis was used to estimate lethal concentrations; LC10, LC15, LC20 and LC25, which are considered sublethal concentrations because they present a mortality below 25%. Later, another bioassay was installed to evaluate some biological parameters, such as: duration period of the larval phase, weight of individuals in the larval stage, weight of individuals in the pupal phase and sexual ratio. All the concentrations showed a significant increase in the larval period, with highlight to LC25 that presented the longest period, reaching more than 36 days. There were also significant differences in the weight of caterpillars and pupal weight. Only LC10 concentration showed no significant difference in relation to the control treatment in the pupae weight parameter. Sublethal Bt concentrations are capable of interfering in the development of H. armigera individuals, and may contribute to reduce the damage caused by this pest.

Effects of Buxus chinensis extract, Bacillus thuringiensis and nuclear polyhedrosis virus (NPV) mixture on certain biological aspects of Spodoptera littoralis were studied against the 2nd and 4th larval instars of S. littoralis. The mixture of the three compounds was the most toxic against the 2nd and 4th instar larvae, where it caused high percentage of mortality, while B. thuringiensis (Dipel 2x) and nuclear polyhedrosis virus (NPV) mixture induced a slight effect against the 2nd and 4th instars. Regarding the ethanolic extract of Buxus chinensis leaves, it was more effective than B. thuringiensis (Dipel 2x) or nuclear polyhedrosis virus (NPV) in respect of pupal mortality and larval , pupal and adult duration. This plant extract also reduced the fecundity and fertility of females emerged from the treated larvae of S. littoralis.

Submitted by NILSON VELOSO BEZERRA null (nbezerra@yahoo.com) on 2016-07-01T21:32:28Z No. of bitstreams: 1 REPOSITÓRIO 3.pdf: 1649773 bytes, checksum: bbd9ec85d56b05b1d027d90e58cddbaa (MD5) Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-07-04T12:46:34Z (GMT) No. of bitstreams: 1 bezerra_nv_dr_jabo_par.pdf: 1054249 bytes, checksum: 0cfa07638ddafda983e59ecbdc48c0c9 (MD5) Made available in DSpace on 2016-07-04T12:46:34Z (GMT). No. of bitstreams: 1 bezerra_nv_dr_jabo_par.pdf: 1054249 bytes, checksum: 0cfa07638ddafda983e59ecbdc48c0c9 (MD5) Previous issue date: 2016-06-02 Objetivou-se avaliar a ação do Bacillus thuringiensis var. kurstaki (Berliner) no epitélio do intestino médio de lagartas de Brassolis sophorae L. (Linnaeus). O trabalho foi realizado no período de janeiro a novembro de 2015 no Laboratório de Entomologia Agrícola Aplicada da Universidade Federal Rural da Amazônia (UFRA), Belém-PA. As lagartas foram coletadas na plantação de palma de óleo da empresa Companhia Reais Agroindustriais, pertencente ao Grupo AGROPALMA, localizada no km 70 da Rodovia PA-150, Município de Tailândia, Pará (Latitude: 2⁰ 38’ S. Longitude: 48⁰ 13’ W. Gr.). Aplicou-se formulação comercial Dipel® de B. thuringiensis var. kurstaki por meio de imersão de folhas de palma de óleo, previamente lavadas em água destilada e secas em temperatura ambiente, as quais foram incorporadas à dieta fornecida às lagartas de terceiro instar de B. sophorae mantidas em recipientes plásticos. A aplicação do bioinseticida por meio da imersão das folhas de palma de óleo mostrou-se eficiente no controle de lagartas, atingindo níveis de 100% de mortalidade em todas as concentrações utilizadas (0,25; 0,5; 0,75 e 1,00 L/ha) variando para menos o tempo de efetividade de acordo com o aumento da concentração. Sintomas de infecção pelo B. thuringiensis foram identificados nas lagartas e confirmadas através da observação microscópica de alterações morfológicas e formação de vacúolos no citoplasma das células epiteliais do intestino médio das lagartas. A utilização do Dipel® nessas concentrações ocasionou efeito citotóxico local, produzindo histólise no intestino médio de lagartas de B. sophorae, levando, provavelmente, ao funcionamento anormal desse tecido, alterando a secreção de enzimas, a absorção dos nutrientes e a renovação celular e consequentemente a morte. This study aimed to evaluate the action of Bacillus thuringiensis var. kurstaki (Berliner) in the midgut epithelium crawler Brassolis sophorae L. (Linnaeus). The work was carried out from January to November 2015 in Applied Agricultural Entomology Laboratory of the Federal Rural University of Amazonia (UFRA), Belém-PA. Larvae were collected in the oil palm plantation company Royal Agroindustrial company belonging to AGROPALMA Group, located at kilometer 70 of Highway PA-150, City of Thailand, Pará (Latitude: 2⁰ 38 'S. Longitude: 48⁰ 13' W. Gr.). applied Dipel® commercial formulation of B. thuringiensis var. kurstaki by dipping palm leaf oil, previously washed with distilled water and dried in room temperature water, which were incorporated into the diet fed to third instar larvae of B. sophorae kept in plastic containers. The application of the biopesticide by immersing the oil palm leaves was efficient in the control of caterpillars, reaching levels of 100% mortality in all used concentrations (0.25, 0.5, 0.75 and 1, 00 L / ha) for less time varying effectiveness according to the concentration. Symptoms of infection with B. thuringiensis were identified in the caterpillars and confirmed by microscopic observation of morphological changes and vacuole formation in the cytoplasm of epithelial midgut cells of caterpillars. The use of these concentrations resulted Dipel® location cytotoxic effect, producing histolysis in the midgut of track B. sophorae leading probably abnormal operating this tissue, altering enzyme secretion, absorption of nutrients and cellular renewal and thus the death.

Diet choice tests were conducted to examine the effects of Bacillus thuringiensisBerliner on larval feeding behavior of Dipel-resistant and susceptible strains of European corn borer, Ostrinia nubilalis(Hubner). Larvae (first through fourth instars) were presented an untreated standard diet and three diets incorporating different concentrations of a commercial formulation of B. thuringiensis ,D ipel ES TM . Significantly higher proportions of susceptible and resistant larvae were found on the control diet compared to the proportions recorded on any of the Dipel-treated diets. Soon after release (0.5 to 3 h), the occurrence of larvae on each of the diets was similar across different instars. The number of first and second instars on the control diet increased steadily over 72 h after release, when 43 to 75% of larvae were found on the control diet. The proportion of third and fourth instars on the control diet also increased initially, with an equilibrium occurring 12 to 24 h later when 30 to 40% of larvae were found on the control diet. Both strains appeared to avoid the Dipel-treated diets and their responses were similar over different Dipel concentrations. The Dipel-resistant strain showed higher ability to avoid the treated diets than the susceptible strain.

The effect of Dipel 4L in artificial diet on feeding behavior, occurrence on a specific diet, and growth of corn earworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), was assessed in short-term tests. Third-, fourth-, and fifth-stage laboratory-reared and feral corn earworm larvae were evaluated. Arenas used for each assay included a non-Dipel diet, Dipel-containing diet, and a combination of the two diets. Larval activity was observed immediately after exposure to diet and at 6 and 18 h for third instars and at 6, 8, and 24 h for fourth and fifth instars, respectively. Feral and laboratory-reared third, fourth, and feral fifth instars avoided Dipel-treated diet when more suitable food was available. Third and fourth instars consistently preferred non-Dipel-containing diet when presented a choice of foods. Corn earworm growth was delayed when larvae were subjected to Dipel-treated diet in choice and no-choice assays compared with larvae provided untreated diet. Larvae presented a choice of diets grew more rapidly than those presented Dipel-treated diets in no choice arenas. Larval feeding frequency and weight gain were superior when larvae were supplied untreated diet than when restricted solely to a Dipel-treated diet. Larvae presented a choice of diets spent more time feeding and fed more frequently on untreated diet than Dipel-treated food. These data indicate that corn earworm presented a choice of Bacillus thuringiensis (Bt) and non-Bt diets may have an increased probability of completing development compared with those restricted to Bt-laced sources.

A field strain of pink bollworm Pectinophora gossypiella (Saund.) collected from Sharquia Governorate, Egypt was exposed to the selection pressure of the for-mulation of Bacillus thuringiensis subsp. Kurstaki, Dipel 2x under laboratory condi-tions. Resistance ratio attained 16-fold based on the susceptible strain after 14 gen-erations of selection. Study the response of Dipel 2x resistant strain to some insecti-cides indicated that there is no cross resistance to the conventional insecticides, es-fenvalerate, chlorpyriphos and thiodicarb or the bioinsecticides Ecotech and Agerin. These data may be emphasizing the possibility of rotation the Dipel 2x with these insecticides in pest control program of pink bollworm to manage resistance to Bt products.

Dipel-resistant and -susceptible strains of Ostrinia nubilalis (Hubner) were evaluated for larval mortality and growth inhibition when fed diets containing individual Bacillus thuringiensis protoxins. Resistance ratios for four of the protoxins in Dipel (Cry1Aa, Cry1Ab, Cry1Ac, and Cry2Aa) were 170-, 205-, 524-, and >640-fold, respectively, considerably higher than the 47-fold resistance to Dipel. The Dipel-resistant strain was 36-fold resistant to Cry1Ba, a protoxin not present in Dipel. Another non-Dipel protoxin, Cry1Ca, did not cause significant mortality for either resistant or susceptible larvae with doses as high as 1.0 mg/ml. In an evaluation of larval growth inhibition, resistance to Cry1Aa, Cry1Ab, Cry1Ac, and Cry1Ba was significant at concentrations of 0.054 and 0.162 μg/ml. However, growth inhibition with Cry2Aa was not significant at either dose. These data provide information on the spectrum of resistance and cross-resistance to individual Cry protoxins in this strain.

The survival of KS-SC DiPel-resistant and -susceptible European corn borer, Ostrinia nubilalis (Hubner), was evaluated on different tissues from corn, Zea mays L., hybrids, including a nontransgenic and two transgenic corn plants (events MON810 and Bt11) expressing high doses of Bacillus thuringiensis (Bt) Cry1Ab. The survival of Bt-resistant and -susceptible third instars was similar after a 5-d exposure to transgenic plant tissues. Survivors eventually died when returned to Bt corn tissues, but many were able to continue development when transferred to non-Bt corn tissues. Survival of resistant and susceptible larvae also was evaluated in bioassays with dilutions of leaf extracts from the three corn hybrids incorporated in an artificial diet. In these assays, survival was significantly higher for resistant O. nubilalis neonates at three of the five dilutions compared with the susceptible strain, but the resistance ratio was only 2.2- and 2.4-fold for MON810 and Bt11, respectively. The data demonstrate that Bt-resistant and unselected control O. nubilalis larvae were similar in susceptibility to MON810 and Bt11 event corn hybrids. Although we were unable to evaluate the Cry1Ab protein that larvae were exposed to in the transgenic tissue because of company restrictions, Cry1Ab protoxin produced in Escherichia coli was incubated with extracts from non-Bt corn leaves to simulate the in planta effect on the transgenic protein. Cry1Ab protoxin was hydrolyzed rapidly by enzymes in the corn extract into peptide fragments with molecular masses ranging from 132 to 74 kDa, and eventually 58 kDa. Overall, these data suggest that plant enzymes hydrolyze transgenic toxin to one that is functionally activated. Therefore, resistant insect populations with reduced proteinase activity do not seem to pose a threat to the efficacy of commercial MON810 and Bt11 corn hybrids.

The Kansas Dipel-resistant and susceptible European corn borer, Ostrinia nubilalis (Hübner), were evaluated in the greenhouse on different Bt transgenic events expressed in corn hybrids. There were important differences in the resistance offered by the different Bt event corn hybrids. Hybrid comparison tests indicate that these Dipel-resistant first-instar European corn borer were not able to survive to adulthood on whorl-stage MON810, Bt11, or 176 Bt event corn plants. Third instars did not survive to adulthood on whorl-stage MON810 or Bt11 event corn plants but a small number of fifth instars were found on whorl-stage DBT418 plants infested with Dipel-resistant larvae. First and third instars of these Dipel-resistant European corn borers caused more leaf-feeding damage and more tunneling on whorl-stage Bt-corn plants than did the Dipel-susceptible European corn borers. However, in the single Bt corn hybrid test, there was no survival of the Dipel-resistant European corn borers on DK580BtX or MAX454 Bt plants 35 to 42 d after they had been infested with first instars. These results demonstrate that the current Kansas selection of Dipel-resistant European corn borer strain cannot establish reproducing populations in the tested Bt corn lines and hybrids.

The efficacy of neem kernel cake powder water extract (NKCP-WE) and Dipel 2x (Bacillus thuringiensis var. kurstakt) in controlling the diamondback moth (DBM), Plutella xylostella Linn. (Lepidoptera: Yponomeutidae), on cabbage was evaluated in screenhouse experiments. All concentrations of NKCP-WE tested were larvicidal and plants treated with 25 and 50 g/l NKCP-WE retained larvicidal activity for up to 2 weeks after application. The efficacy of 25 and 50 g/l NKCP-WE and 0.5 g/l Dipel 2x was compared by observing DBM development on the treated plants and yields of those plants. Dipel 2x-treated plants had less DBM larval infestation than the neem-treated plants but the latter treatment gave better yield. The implications of these observations are discussed.

Frequency domain terahertz (THz) spectroscopy was used to study DiPel® PRO DF, a commercial insecticide containing 54% Bacillus thuringiensis subsp. kurstaki. The mixture contains Bt spores as well as Bt protein toxins. Microscopic imaging revealed that DiPel® is composed of millimeter scale coarse particles and SEM photos indicate Bt spores are in these particles. The substantial attenuation from transmission measurements suggested strong signal scattering since the dimensions of particles (~1 mm-400 μm) are close to the THz wavelengths (~750-250 μm). Alternatively, periscope reflection measurements were carried out and a 917 GHz absorbance signature was observed. This is explained by the Mie theory that a portion of absorption is accompanied with scattering. Resonant absorption can be excited as long as internal vibration exists within particles. Therefore, absorption can be detected by the reflectivity measurements. To prove this hypothesis, Bt spores were separated from the large DiPel® coarse particles and their presence was again confirmed with microscopy. A transmission scan of the extracted spore samples was then repeated. The 917 GHz absorbance signature was present and consistent with transmissions on culture-grown, freshly harvested Bt spore samples.

The effect of sunlight radiation, rainfall and droplet spectra of sprays on per -sistence of a Bacillus thuringiensis subspp. kurstaki (Btk) formulation, DiPel®76AF, was examined after application onto spruce [Picea glauca (Moench) Voss] foliage. The investigation consisted of three studies: (i) Study 1: a laboratory microcosm study to examine the photostability of DiPel 76AF deposits on foliage after different periods of exposure to two radiation intensities, (ii) Study II: a laboratory microcosm study to examine the rainfastness of foliar deposits after exposure to different amounts of rainfall consisting of two separate droplet spectra, and (iii) Study Ill: a field microcosm study to investigate the influence of two different droplet spectra of DiPel 76AF sprays on foliar persistence of Btk under natural weathering conditions. In all studies, persistence of Btk was investigated both by bioassay [using spruce budworm (Choristoneura fumiferana Clemens)] and total protein assay. The findings of Study I indicated that bioactivity of foliar deposits decreased with increasing duration of exposure to radiation, and with increasing radiation intensity. The half-life (DT 50 , the exposure period required for 50% of the initial bioactivity to disappear) was 5.1 d for the low intensity, and 3.9 d for the higher intensity. In contrast with the bioassay results, the total protein levels [determined by the bicinchoninic acid (BCA) method] showed no decrease with increasing duration of exposure, or with increasing radiation intensity. The findings of Study II indicated that bioactivity of foliar deposits decreased with increasing cumulative rainfall. A new term, RF 50 [the amount of rain (in mm) required to washoff 50% of the initial deposit], was introduced to understand the relationship between rainfall intensity and reduction in bioactivity. When the same amount of rain was applied in different droplet sizes, the RF 50 value was high (5.2 mm) for the small rain droplets, and was low (2.9 mm) for the large rain droplets. Similar to the bioassay results, the total protein concentrations (determined by the BCA method) decreased with increasing amount of rain and with increasing rainfall intensity. The RF 50 value (obtained using ng protein /cm 2 ) was 5.4 mm for the small rain droplets, and was 3.4 mm for the large rain droplets. The field microcosm study indicated that when DiPel 76AF was applied in small droplets (D V.5 of 65 μm), the persistence of bioactivity was ca 8.0 d, whereas when it was applied in large droplets (D V.5 of 130 μm) it was ca 11 d. Bioactivity decreased with time after spray, and the DT 50 was 1.98 d for the spray of small droplets, and 2.87 d for that of large droplets. Similar to the bioactivity, the total protein concentrations also decreased with time after spray, and the DT 50 values for the small and large droplet spectra were 3.45 and 6.07 d respectively.

Bioassays with MVP, a genetically engineered form of a toxin of Bacillus thuringiensis subsp. kurstaki, demonstrated that a plateau in concentration response depended on the temperature and time when mortality was assessed. The presence of a plateau did not indicate resistance in diamondback moth, Plutella xylostella (L.). Comparisons of LC50S at 25 degrees C indicated that MVP acted more slowly than a conventional B. thuringiensis subsp. kurstaki formulation (Dipel 2X). However, LT50S of the preparations at a given concentration did not vary substantially. At 28 degrees C, responses were approximately equal over time. To avoid artifacts in analyses of concentration-response data, we recommend that bioassays be designed carefully to account for subtle differences in the behavior of genetically engineered versus conventional preparations of B. thuringiensis.