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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

Rearing density effects on premigrant traits of the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae)

Ferguson, Holly J. 20 September 2005 (has links)
Laboratory and field studies of the fall armyworm, <i>Spodoptera frugiperda</i>, were undertaken to determine if a high larval rearing density produces premigrant traits, and if these traits can be used as criteria for separating nonpremigrant from premigrant groups. An increase in larval rearing density significantly decreased pupal weight and forewing width in the laboratory but not in the field. The greatest differences in developmental time among laboratory density treatments were 0.6 d and 1.07 d for females and males, respectively, but differences were not considered biologically significant. Rearing density did not affect duration of pupal stage in the field-reared fall armyworms. An actograph was used to measure adult flight activity and was validated with videotape recordings of moths in actograph cages. Behaviors other than flying occurred; hence, computer-recorded counts were termed activity counts (one activity count was recorded each time a moth broke an infrared beam directed through a window in an actograph cage). Male moths showed a greater proportion of long-duration activity bouts (spells of activity), a significantly greater activity bout duration, and a generally greater magnitude of activity during peak periods than female moths. Generally, actograph activity was not significantly affected by rearing density. Both mated and unmated females exposed to males showed very little actograph activity, and most of the females mated when exposed to males, regardless of rearing density. An increase in rearing density in the laboratory significantly increased adult lipid reserves, but higher lipid reserves were not related to a higher activity potential. Although larval rearing density did not affect wing-loading values, the fall armyworm as a migrant species showed lower than theoretically expected wing-loading values. Because some premigrant traits were produced by increasing the rearing density and other premigrant traits and behaviors were not produced, it is inconclusive that premigrants were produced by these rearing methods. Based on these results and data taken from the literature, there is reason to believe that the fall armyworm does not have a separable premigrant phase, and that components of weather are more influential than larval density in initiating its migratory behavior. / Ph. D.

Pharmacokinetic mechanisms associated with cypermethrin toxicity and synergism in larval and adult Helicoverpa zea (Boddie), Spodoptera frugiperda (J.E. Smith), and Agrotis ipsilon (Hufnagle) (Family noctuidae) /

Usmani, Khawja Amin, January 1998 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaves [224]-254). Also available on the Internet.

Pharmacokinetic mechanisms associated with cypermethrin toxicity and synergism in larval and adult Helicoverpa zea (Boddie), Spodoptera frugiperda (J.E. Smith), and Agrotis ipsilon (Hufnagle) (Family noctuidae)

Usmani, Khawja Amin, January 1998 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaves [224]-254). Also available on the Internet.


AL-HUMIARI, AMIN ABDALLAH. January 1985 (has links)
The Fall Armyworm is a serious pest of many crops throughout most of the Western Hemisphere particularly those belonging to the family Gramineae. This pest is usually controlled by insecticides which, however, cause many health and environmental problems. Although a rich bank of sorgum germplasm occurs in Yemen, no effort has been made to identify the Yemeni cultivars which might express resistance to armyworm attack. There is very little information to show at what time of the growing season and at what planting stage the sorghum cultivars are most susceptible to armyworms. Therefore, eight Yemeni and two American sorghum cultivars were planted in Tucson, Arizona, during 1983 and 1984. The experimental design was a randomized complete block arranged in split-split plots with four replications. The main plots were the varieties, and subplots were two planting dates and two infestation times. The plants were artificially infested with laboratory reared, first instar larvae. Infestation consisted of five larvae per plant in 1983 and ten in 1984. Results demonstrate the 'IBB' and 'TURBA' received the least leaf damage and 'SGIRL-MR1' and 'ALBAIDA' received the most in 1983. However, during 1984, 'TURBA' and 'HAIDRAN' showed the greatest degree of resistance and 'SGIRL-MR1', 'AMRAN', 'ALMAHWIT', and 'ALBAIDA' the least.

Efeito do silício aplicado no solo e em pulverização foliar na incidência da lagarta do cartucho na cultura do milho

Silva, Anne Caroline Arruda e [UNESP] 07 August 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-08-07Bitstream added on 2014-06-13T18:35:01Z : No. of bitstreams: 1 silva_aca_me_botfca.pdf: 486573 bytes, checksum: 7da2829da43c73fb9381ae790a958b36 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Atualmente diversos estudos têm sido desenvolvidos sobre a utilização dos silicatos na adubação de plantas e embora ainda não conclusivos, seu emprego tem sido intensificado em algumas regiões agrícolas do país. No entanto, como o silício não é considerado um nutriente essencial de plantas, uma das principais justificativas para seu emprego na agricultura tem sido o incremento da resistência a pragas e doenças. Dessa forma, foram instalados dois experimentos seguindo o delineamento experimental de blocos ao acaso para verificar o efeito do silício sobre a lagarta-do-cartucho do milho em condições de campo. O primeiro experimento foi composto por 10 tratamentos e 4 repetições, com parcelas de 10 linhas de 10 m e visou verificar o efeito de uma formulação comercial contendo 25% de óxido de silício (12% de Si solúvel) e 15% de óxido de potássio, desenvolvida para aplicação através da pulverização foliar. Os tratamentos no primeiro experimento consistiram da aplicação da formulação silicatada nas concentrações 2, 4 e 8 mL/L, em pulverização aos 15, aos 15 e 30 e aos 15, 30 e 45 dias após a germinação das plantas. O segundo experimento contou com 7 tratamentos e 4 repetições, com parcelas de 7 linhas de 10 m e visou verificar o efeito de uma formulação comercial constituída por escória de siderurgia, aplicada no sulco de semeadura, nas doses de 400 e 800 kg/ha, na semeadura, só na cobertura, e na semeadura e cobertura. Nos dois experimentos avaliou-se a incidência da lagarta-do-cartucho do milho aos 15, 30, 45 e 60 dias após a germinação e os respectivos danos através de uma escala de notas. Também foram avaliados os parâmetros vegetativos indicadores do desenvolvimento como, altura da planta; número de folhas vivas; data do fechamento do cartucho e data do lançamento do pendão e o número de espigas produzido. Finalmente foi a avaliada... / At present several studies about the use of silicates on plant fertilization have been developed, and although there is nothing conclusive regarding it, their use has been intensified in some Brazilian agricultural regions. However, since silicon is not considered an essential plant nutrient, the main reason for its use in agriculture has been the increase in the plant resistance to pests and diseases. This way, two experiments were carried out to verify the effect of silicon on fall armyworm in field corn. The first experiment used a randomized block design with 10 treatments and 4 replicates and with plots of ten 10 m rows to verify the effect of a commercial formula containing 25% of silicon oxide (12% of soluble Si) and 15% of potassium oxide, developed for foliar application. The treatment on the first experiment consisted of the silicate formula at concentration of 2,4 and 8 mL/L, sprayed at 15 days, at 15 and 30 and at 15, 30 and 45 days after plant germination. The second experiment also used a randomized block design with 7 treatment and 4 replications, and with plots of seven 10m rows, to verify the effect of a commercial formula composed by silicate slag applied in the soil, with dosages of 400 and 800 kg/ha, in the sowing, only in coverage and both. The incidence of fall armyworm was evaluated at 15, 30 45 and 60 days after the germination and its respective damage through a grade scale in both experiments. Vegetation development indicator parameters were also evaluated as: plant height; number of living leaves; date of the flowering; number of corncobs. The production was finally evaluated by weighing the corncobs and grain/plant. The data obtained indicated that silicon did not interfere neither on the plant vegetable development nor in the occurrence of fall armyworm. It did not interfere neither on the damage caused by this pest, nor on the number of and grains produced.

Efeitos de proteinas Cry e vip nos parâmetros biológicos de populações de Spodoptera frugiperda (Smith, 1797) e injúrias nas plantas de milho por Lepidópteros / Effect of Cry and vip proteins in the biology of populations of Spodoptera frugiperda (Smith, 1797), and on injuries in maize plants caused by Lepidópteros

Crosariol Netto, Jacob [UNESP] 31 January 2017 (has links)
Submitted by JACOB CROSARIOL NETTO Crosariol Netto (jacob_netto@hotmail.com) on 2017-02-24T21:47:39Z No. of bitstreams: 1 Tese_Jacob_Crosariol_Netto.pdf: 1461716 bytes, checksum: 8e775579f98ce9756ce677febd37324b (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-03-06T17:33:34Z (GMT) No. of bitstreams: 1 crosariolnetto_j_dr_jabo.pdf: 1461716 bytes, checksum: 8e775579f98ce9756ce677febd37324b (MD5) / Made available in DSpace on 2017-03-06T17:33:34Z (GMT). No. of bitstreams: 1 crosariolnetto_j_dr_jabo.pdf: 1461716 bytes, checksum: 8e775579f98ce9756ce677febd37324b (MD5) Previous issue date: 2017-01-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The fall armyworm Spodoptera frugiperda is the major pest of corn in tropical and subtropical regions in the American Continent. Among the most used methods to control this pest in Brazil, it highlights the use of genetically modified plants from the insertion of a Bacillus thuringiensis gene that confers to the plant the expression of proteins with insecticidal actions. However, after two or three years these technologies reduce the degree of suppression of larvae, mainly due to the continuous and inadequate use of the technology. The objective of this work was to study in field conditions, the behavior of Bt corn hybrids against lepidopteran attacks as S. frugiperda and Helicoverpa zea in four corn-producing regions of São Paulo State, as well as to study in laboratory conditions the comparative biology of populations of S. frugiperda collected in these regions. Field experiments were carried out during the second corn season in 2014 in the regions of Médio Paranapanema, Centro Norte, Noroeste and Norte of São Paulo State where were used 25 corn cultivars with the expression of different insecticidal proteins. To the comparative biology study, the larvae were collected in the four regions of the state, the larvae were sent to Integrated Pest Management Laboratory of FCAV-Unesp where the experiments were carried out with leaves of corn hybrids of different technologies. The results of field experiments demonstrate that the insecticidal protein VIP3Aa20 presents a high level of suppression on the populations of S. frugiperda and H. zea, in addition, the corn hybrids that express the insecticidal protein Cry1F were the most susceptible against the attack of these two pests. Through the results obtained from the experiments of comparative biology, it was verified that the insecticidal protein VIP3Aa20 provided 100% of mortality of larvae from the four regions. The hybrid with expression of the proteins Cry1A.105 + Cry2Ab2 + Cry1F was the one that provided low viability of S. frugiperda larvae coming from the four regions of the São Paulo State. The hybrid that expresses the insecticidal protein Cry1F provided low levels of suppression as well as low adverse effects in the development of S. frugiperda coming from the four regions of the state, indicating that the populations present in these four regions are resistant to the action of this insecticidal protein. / A lagarta do cartucho Spodoptera frugiperda é a principal praga da cultura do milho nas regiões tropicais e subtropicais do continente americano. Dentre os métodos mais utilizados para o controle desta praga no Brasil, destaca-se o uso de plantas geneticamente modificadas a partir da inserção de um gene da bactéria Bacillus thuringiensis que confere a planta a expressão de proteínas com ações inseticidas. No entanto, durante dois ou três anos estas tecnologias reduziram o grau de supressão às lagartas, principalmente pelo uso continuo e inadequado da tecnologia. O objetivo deste trabalho foi estudar em condições de campo, o comportamento de híbridos de milho Bt frente ao ataque de lepidópteros, como a S. frugiperda e Helicoverpa zea, em quatro regiões produtoras de milho do estado de São Paulo, bem como estudar em condições de laboratório a biologia comparada de populações de S. frugiperda coletadas nestas regiões. Os experimentos de campo foram realizados no período da segunda safra de milho, no ano de 2014, nas regiões do Médio Paranapanema, Centro Norte, Noroeste e Norte do estado de São Paulo, onde foram utilizados 25 cultivares de milho com expressão de diferentes proteínas inseticidas. Para o estudo de biologia comparada foi realizada a coleta de lagartas nas quatro regiões do estado, as lagartas foram enviadas ao laboratório de Manejo Integrado de Pragas da FCAV-Unesp onde foram realizados os experimentos com folhas de híbridos de milho de diferentes tecnologias. Os resultados dos experimentos realizados a campo demonstram que a proteína inseticida VIP3Aa20 apresenta alto nível de supressão sobre as populações de S. frugiperda e Helicoverpa zea, além disso, os híbridos de milho que expressam a proteína inseticida Cry1F foram os mais suscetíveis frente ao ataque destas duas pragas. Através dos resultados obtidos para os experimentos de biologia comparada, constatou-se que a proteína inseticida VIP3Aa20 proporcionou 100% de mortalidade das lagartas oriundas das quatro regiões. O híbrido com expressão das proteínas Cry1A.105 + Cry2Ab2 + Cry1F foi o que proporcionou menor viabilidade de lagartas de S. frugiperda oriundas das quatro regiões do estado. O híbrido que expressa a proteína inseticida Cry1F proporcionou baixos níveis de supressão além de baixos efeitos adversos no desenvolvimento de S. frugiperda oriundas das quatro regiões do estado, indicando que as populações presentes nestas quatro regiões se encontram resistentes a ação desta proteína inseticida.

The development of a baculovirus expression system for the production of Helicoverpa armigera stunt virus capsids for use in the encapsidation of foreign molecules

Mosisili, Kekeletso Mpho Thakane January 2003 (has links)
The capsid protein of Helicoverpa armigera stunt virus (HaSV) a T=4 insect virus was expressed in Spodoptera frugiperda 9 cells using a baculovirus vector. When the insect cells were infected at a high MOl the expressed coat protein assembled into virus-like particles (VLPs) that spontaneously underwent maturation and were morphologically indistinguishable from wild-type HaSV. The VLPs were electron dense when viewed under EM and encapsidated their coat protein mRNA. When Sf9 cells were infected at a low multiplicity of infection (MOl) the expressed capsid protein assembled into procapsids that did not spontaneously undergo maturation. These procapsids underwent autoproteolytic maturation cleavage when they were treated with an acidic buffer. The procapsids were used in the encapsidation of a FITC labelled peptide. The peptide encapsidating VLPs showed an increase in their buoyant density that was not collaborated by an increase in the concentration of the FITC labelled peptide detected when these samples were compared to control samples with similar buoyant densities.

Liberação de linhagens de Trichogramma pretiosum para controle biológico de Spodoptera frugiperda na cultura do milho / Liberation of Trichogramma pretiosum strains for biological control of Spodoptera frugiperda in the field corn

Cordeiro, Ederval Silva 27 September 2006 (has links)
Made available in DSpace on 2017-07-10T17:37:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-09-27 / The objectives of this work were: to identify lineages of Trichogramma which occur naturally in eggs of Spodoptera frugiperda, in the West of Paran?; to select, under laboratory conditions, about eggs of the alternative host Anagasta kuehniella (Zeller), the lineage with the highest potential of parasitism and to evaluate the efficency of the selected line to control S. frugiperda in field conditions. Collections were realized in commercial, conventional and organic crops in properties in the West of Paran?. The collected lineages in the field were named (E1, E3, L3) and after, identified as T. pretiosum. The biology of the collected lineages in the field and the line (L2) breeded massively under laboratory conditions in Anagasta kuehniella eggs, were realized in temperature of 25?2 ?C; 70 ? 10% R.U. and 14 h. photophase. After the line selection through the analysis of biological parameters, two liberation experiments were performed in field conditions. On experiment 1, 100 thousand parasitoids per hectare were liberated and evaluated weekly, evaluating the plants which sufferd or not, the fall armyworm attack, observing the leaf damages, as scrape and perforation. On experiment 2, 200 thousand parasitoids per hectare were liberated and evaluated weekly, observing the same damages caused by Spodoptera related on the previous experiment. L2 was selected, due to this line large number of parasited eggs and larger number of females presented, when compared to males for later use in the field. In general, the conclusion is that in both experiments (1 and 2), there was significant reduction of the number of the damaged plants by S. frugiperda in treated areas with T. pretiosum / Os objetivos deste trabalho foram: identificar linhagens de Trichogramma que ocorrem naturalmente em ovos de Spodoptera frugiperda, na região Oeste do estado do Paraná; selecionar em laboratório, sobre ovos do hospedeiro alternativo Anagasta kuehniella (Zeller), a linhagem com o maior potencial de parasitismo e avaliar a eficiência a campo da linhagem selecionada no controle de S. frugiperda. Para isso foram realizadas coletas em plantações comerciais, convencionais e orgânicas em propriedades da região Oeste do Paraná. As linhagens coletadas a campo foram denominadas de (E1, E3, L6) e posteriormente identificadas como T. pretiosum. Foi realizada a biologia das linhagens coletadas a campo e também da linhagem (L2) criada massalmente em laboratório em ovos de Anagasta kuehniella em temperatura de 25±2 ºC; 70 ± 10% U.R. e 14 h. de fotofase. Após a seleção da linhagem pela análise dos parâmetros biológicos, foram realizados dois experimentos de liberação em campo. No experimento 1, 100 mil parasitóides por hectare foram liberados e avaliados semanalmente, levando em consideração as plantas que sofreram ou não, o ataque da lagarta-do-cartucho, observando os danos foliares, como raspagem e perfuração. No experimento 2, 200 mil parasitóides por hectare foram liberados e avaliados semanalmente, levando em consideração os mesmos danos causados pela Spodoptera citado no experimento anterior. Foi selecionado a L2, devido esta linhagem apresentar maior número de ovos parasitados e maior quantidade de fêmeas em relação aos machos para posterior uso em campo. No geral, pode se concluir que em ambos os experimentos (1 e 2) houve redução significativa do número de plantas danificadas por S. frugiperda em áreas tratadas com T. pretiosum.

The effect of some micronutrients on the resistance of highland bentgrass to fall armyworms

Watson, Stephen Lawrence January 2011 (has links)
Digitized by Kansas Correctional Industries

Functional role of recombinant cysteine protease on Spodoptera frugiperda peritrophic matrix

Mohan, Srinidi, January 2006 (has links)
Thesis (Ph.D.) -- Mississippi State University. Department of Biochemistry and Molecular Biology. / Title from title screen. Includes bibliographical references.

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