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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.
31

Comparación de efectividad de distintos insecticidas en el control de “Trips” Thrips tabaci L., en el cultivo de cebolla (Allium cepa L.) Cultivar Sivan, En el PROTER – SAMA

Machaca Vargas, Victoria Angélica 14 February 2013 (has links)
El presente trabajo de tesis titulado “COMPARACIÓN DE EFECTIVIDAD DE DISTINTOS INSECTICIDAS EN EL CONTROL DE TRIPS (Trips tabaci L.), EN EL CULTIVO DE CEBOLLA Allium cepa L. CULTIVAR SIVAN, (PROTER) – SAMA”; se realizó con el objetivo de evaluar la efectividad de distintos insecticidas en el control de trips (Trips tabaci), en el cultivo de cebolla cultivar SIVAN en el PROTER – SAMA. Se utilizó el cultivar Sivan y 4 insecticidas T1: EPINGLE 10 EC; T2: PROVADO COMBI; T3: REGENT; T4: FURIA y un testigo T0: Sin aplicación. El área experimental fue de 50,00 m x 15 m teniendo un área total de 750 m2; la siembra se realizó a un distanciamiento de 0,10 m entre plantas y 1,00 m entre líneas. Se empleó el diseño de bloques completos aleatorios con 5 tratamientos y 4 repeticiones, para el análisis estadístico se utilizó el análisis de varianza y para la diferencias de promedios se utilizó la prueba de significación de Duncan y Tukey. La mayor efectividad para el número del thrips tabaci vivos/planta en cultivar Sivan, en las siete aplicaciones, se obtuvieron con los tratamientos T2: PROVADO COMBI y T3: REGENT, sin embargo T1: EPINGLE 10 EC y T4: FURIA no tuvieron una efectividad significativa. Los rendimientos (t/ha) más altos se obtuvieron con los tratamientos T3: REGENT y el T2: PROVADO COMBI con 55,22 t/ha y 54,84 t/ha, respectivamente en el tercer lugar se ubicó el T4: FURIA con 53,06 t/ha.
32

A Synopsis of the Canadian Thysanoptera

Chiasson, Hélène January 1985 (has links)
Note: page 74 is missing from archival and circulating copies / The present state af knowledge of the order Thysanaptera in Canada is reviewed. The aoder has been sorely neglected since Provenchar submitted a list af 35 eastern Canadian species in 1890. In contrast to the latest previaus estimate of 102 species (Heming, 1979), the number of species found in this study is 174 (143 described and 31 undescribed species). One new genus and five new species are reported as well as the European species Odontothrips biuncus which has been found for the first time in North America. Descriptions, illustrations and a dichatamaus key to the Canadian genera of the Thysanaptera ara given for the first time. Also included are lists of the species. hitherto found in Canada along with their localities•• and habitats•• In addition, an alternative computer-compatible key is presented for the suborder Tubullfera. The distribution and study af the order in Canada are discussed and notes on collection, classification, biology and economic importance are given. / Ce travail revise l’etat de nos cannais.ance. sur l’ordre de. Thysanopteres au Canada. Ce groupe a fait l’objet de peu d’etudes depuis la publication de Provencher (1890), qui enumerait 35 especes pour l’est du Canada. Dans la presente etude, nous rapportons . 174 especes (143 especes decrites, 31 especes non decrit••) alors qu’Heming (1979) n’en citait que 102 especes. pour ce pays. On y cree un nouveau genre et 5 nouvelles especes, en plus de recolter pour la premiere fois l’espece europeanne, Odonthrips biuncus en Amerique du Nord. L’auteur decrit et illustre pour la premiere fois. les. genres de Thvsanoptere. representes dans la fauna canadienne. De plus, on y trouve une liste des especes presentes au Canada, accompagnee de notes sur leur repartition geographique et leur habitat. On y inclut un tableau dichotomique conventionnel ainsi qu’un tableau de determination adape a l’ordinateur. pour Ie sous-ordre des Tubuliferes. Ce travail fournit egalemant, pour les Thysanopteres du Canada, une discussion sur leur repartition Geographique et des renseignements sur leur recolte et classification, leur biologie et importance economique.
33

Seasonal climatic variations influence the efficacy of predatory mites used for control of western flower thrips on greenhouse ornamental crops

Hewitt, Laura 17 January 2013 (has links)
This research investigated seasonal climate changes within greenhouses and the impacts they have on efficacy of the predatory mites Amblyseius swirskii and Neoseiulus cucumeris. Controlled environment chamber, greenhouse small-cage, and commercial greenhouse trials were conducted to determine which biological control agent is more efficacious for control of the pest western flower thrips (WFT), (Frankliniella occidentalis) on ornamental crops. When observed under laboratory conditions, predation and oviposition were increased at higher temperatures. Photoperiod and light intensity also have an impact on predatory mites. Predation rates for both mite species were greater when subjected to short day light conditions (8 h light, 11 W/m2). Climates typical of summer (higher temperature and light intensity, long day length), were most favourable in terms of predation and oviposition for A. swirskii. Neoseiulus cucumeris laid more eggs under short day as opposed to long day settings. In summer and winter greenhouse small cage trials, the performance of N. cucumeris and A. swirskii significantly reduced WFT numbers on potted chrysanthemum plants. However, in summer, A. swirskii provided significantly better thrips control than N. cucumeris. The number of adult mites recovered from plants was similar for both mite treatments in winter, while A. swirskii were present in higher numbers throughout the summer trials. Results from leaf damage assessments indicate that A. swirskii is more effective for control of heavy WFT feeding damage in both summer and winter. Results from commercial greenhouse trials yielded similar trends as those found in the summer and winter small cage trials. / University of Guelph, Agriculture and Agri-Food Canada, Vineland Research and Innovation Center, Flowers Canada
34

Visual miscuing of thrips to reduce the incidence of tomato spotted wilt virus in tomatoes

Croxton, Scott David, Foshee, Wheeler G., January 2008 (has links) (PDF)
Thesis (M.S.)--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references.
35

Comportamento e dano de tripes na cultura do milho (Zea mays L.) /

Albuquerque, Fernando Alves de. January 2004 (has links)
Orientador: Wilson Badiali Crocomo / Banca: Carlos Gilberto Raetano / Banca: Adriana Mascarette Labinas / Banca: Ronaldo Pavarini / Banca: Paulo Sérgio Machado Botelho / Resumo: Com o objetivo de identificar as possíveis espécies de tripes associadas à cultura do milho, a espécie predominante, a proporção de adultos e ninfas, a época de ocor-rência, o período crítico de ataque e a influência do sistema de plantio e das condições climáti-cas sobre a população de tripes e métodos de amostragem, foram conduzidos ensaios na Fa-zenda Experimental de Iguatemi, localizada no Município de Maringá, PR, no período de ou-tubro de 2001 a fevereiro de 2004. As avaliações foram realizadas por meio da coleta de tri-pes com armadilhas adesivas azuis e coletando-se plantas de milho, cortadas rente ao solo, colocadas em sacos plásticos e levadas ao laboratório, onde foram lavadas em álcool 70%, para extração dos tripes. A determinação dos danos provocados pelo tripes foi estudada em cinco experimentos inteiramente casualizados, correlacionando diferentes níveis populacionais de tripes e produtividade. Foi empregado o inseticida thiamethoxan, em tratamento de semen-tes, e pulverizações com metamidofós, em diferentes estágios de desenvolvimento das plantas, para obter parcelas com diferentes níveis de incidência de tripes em períodos pré-determinados. Foram identificadas oito espécies de tripes associadas à cultura do milho, na região, sendo Frankliniella williamsi Hood, 1915, a mais freqüente (99,43%). Verificou-se que a incidência de tripes na cultura de milho em solo coberto com aveia dessecada foi menor do que em solo nu, ou coberto por aveia tombada ou incorporada, sendo que imediatamente após a emergência das plantas a população de tripes era composta quase que exclusivamente por adultos imigrantes. A população de formas jovens começou a aumentar a partir dos 14 dias após a emergência das plantas, indicando a capacidade reprodutiva do tripes na cultura do milho. Foi verificada correlação negativa entre... (Resumo completo, clicar acesso eletrônico abaixo). / Abstract: Aiming to identify the possible species of thrips associated to the corn crop, the predominant species, the adult/nymph rate, occurrence time, critical period of attack, influence of the sowing system and climatic conditions on the population of thrips and sampling methods, essays were carried out at the Experimental Farm of Iguatemi, in Maringá, Paraná State, Brazil, from October 2001 to February 2004. The evaluations consisted in collecting thrips with blue adhesive traps and collecting corn plants cuted at soil level, placed into plastic bags and took to the laboratory, where they were washed in alcohol 70%, for the extraction of thrips. The determination of the damages caused by thrips was studied in five experiments, totally randomized, correlating different population levels of thrips and productivity. The insecticide thiamethoxan was applied in seed treatment and methamidophos, in sprayings in different stages of plant development to obtain areas with different levels of incidence of thrips in periods previously established. Eight species of thrips associated to corn crop were identified in the area, being Frankliniella williamsi Hood, 1915, the most frequent (99.43%). It was verified that the incidence of corn thrips in soil covered with dried oats was smaller than in nude soil or in soils covered by cuted or incorporated oat, considering that, immediately after the plants emergence, the population of thrips was composed almost exclusively by emigrant adults. The young population began to increase from 14 days after plant emergence, on indicating thrips reproductivity capacity in corn crops. Negative correlation was verified between the rainfall index and the number of thrips collected in blue traps, but it was not observed any correlation among the number of thrips by corn plant and the number of thrips collected in those traps. It was verified that more than 30 thrips... (Complete abstract, click electronic address below). / Doutor
36

Tripes (Insecta: Thysanoptera) associados a espécies de Fabaceae no meio-norte do Brasil / Thrips (Insecta: Thysanoptera) associated to Fabaceae species in the Brazilian Mid-North

Élison Fabrício Bezerra Lima 25 January 2012 (has links)
Foram coletados tripes em 25 das 40 espécies de fabáceas amostradas em quatro municípios do estado do Maranhão e em dois municípios do estado do Piauí. Foram examinados 818 exemplares de tripes pertencentes a 22 espécies. Doze foram identificadas: Bradinothrips musae (Hood, 1956); Caliothrips phaseoli (Hood, 1912); Dolichothrips indicus (Hood, 1919); Frankliniella brevicaulis Hood, 1937; F. gardeniae Moulton, 1948; F. insularis (Franklin, 1908); F. schultzei (Trybom, 1910); F. tritici (Fitch, 1855); Haplothrips gowdeyi (Franklin, 1908); Heliothrips haemorrhoidalis (Bouché, 1833); Salpingothrips minimus Hood, 1935 e Selenothrips rubrocinctus (Giard, 1901). Cinco são provavelmente novas espécies: Aulacothrips sp.; Frankliniella sp. 3; Hydatothrips sp.; Neohydatothrips sp. e Scolothrips sp. Não foi possível identificar cinco outras espécies, porque o conhecimento taxonômico de um gênero não ainda não está esclarecido (Xylaplothrips Priesner, 1928), porque as espécies pertencem a grupos próximos (Frankliniella sp. 1 e Frankliniella sp. 2) ou devido a diferenças, possivelmente intraespecíficas, com espécies descritas (Plesiothrips sp. e Scirtothrips sp.). Para 17 espécies de fabáceas foram estabelecidos os primeiros registros de associações com tripes. Dolichothrips indicus e Xylaplothrips sp. são novos registros de gêneros no Brasil. Além dessas, B. musae, F. gardeniae, F. tritici, Sa. minimus e Se. rubrocinctus são novos registros para o Meio-Norte do Brasil. Nessa sub-região, indivíduos amarelos e marrons de F. schultzei ocorrem simultaneamente. Foram estabelecidas as primeiras associações de Sa. minimus com espécies vegetais no Brasil. Algumas espécies de tripes conhecidas como pragas de fabáceas, principalmente no sul e sudeste do Brasil, não foram coletadas no Meio-Norte. Uma chave de identificação ilustrada foi elaborada. Os exemplares-testemunhas estão depositados na coleção do Departamento de Entomologia e Acarologia da Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo (ESALQ/USP). / Thrips were collected on 25 out of 40 species of Fabaceae sampled in four municipalities in the state of Maranhão and two municipalities in the state of Piaui. A total of 818 thrips specimens, belonging to 22 species, were examined. From those species, twelve were identified: Bradinothrips musae (Hood, 1956); Caliothrips phaseoli (Hood, 1912); Dolichothrips indicus (Hood, 1919); Frankliniella brevicaulis Hood, 1937; F. gardeniae Moulton, 1948; F. insularis (Franklin, 1908); F. tritici (Fitch, 1855); F. schultzei (Trybom, 1910); Haplothrips gowdeyi (Franklin, 1908); Heliothrips haemorrhoidalis (Bouche, 1833); Salpingothrips minimus Hood, 1935 and Selenothrips rubrocinctus (Giard, 1901). Five probably belong to new species: Aulacothrips sp.; Frankliniella sp. 3; Hydatothrips sp.; Neohydatothrips sp. and Scolothrips sp. It was not possible to identify five other species, because the current taxonomic knowledge of one genus is not clear (Xylaplothrips Priesner, 1928) or the species belong to closely related groups (Frankliniella sp. 1 and Frankliniella sp. 2) or due to slight differences, possibly intraspecific, with described species (Plesiothrips sp. And Scirtothrips sp.). For 17 species of Fabaceae, the first records of association with thrips were established. Dolichothrips indicus and Xylaplothrips sp. are new records of genera in Brazil. In addition, B. musae, F. gardeniae, F. tritici, Sa. minimus and Se. rubrocinctus are new species records for the Mid-North. In this area, yellow and brown individuals of F. schultzei occur simultaneously. It was established the first association of Sa. minimus with plant species in Brazil. Some thrips species known as pests in Fabaceae in Brazil, mainly in southern and southeastern, were not found in Mid-North. An illustrated key was elaborated. Voucher-specimens are deposited in the collection of the Department of Entomology and Acarology, Escola Superior de Agricultura \"Luiz de Queiroz\", Universidade de São Paulo (ESALQ/USP).
37

Characterizing global gene expression and antiviral response in Frankliniella occidentalis infected with Tomato spotted wilt virus

Schneweis, Derek Joseph January 1900 (has links)
Doctor of Philosophy / Department of Plant Pathology / Dorith Rotenberg / Frankliniella occidentalis, the western flower thrips, transmits the plant-pathogenic virus, Tomato spotted wilt virus (TSWV), through a circulative-propagative transmission strategy. The virus infects and replicates in the insect, traversing membrane barriers as it moves from the midgut to the salivary glands for subsequent inoculation of a plant host. Based on well-characterized virus-vector systems, many molecular interactions occur as the virus completes an infection cycle in the vector, and knowledge of transcriptome-wide response of thrips to TSWV has been limited. My research goals were to gain insight into i) the molecular responses that occur in thrips vectors of orthotospoviruses, ii) the role of antiviral defense in viruliferous thrips, and iii) plant transgenic-based strategies for studying thrips gene function and crop-pest control. To this end, my specific research objectives were to: 1) generate, assemble, and annotate a RNA-Seq-derived transcriptome for F. occidentalis using the thrips genome, and to quantify global gene expression in response to TSWV activity in larval, pre-pupal, and adult developmental stages, 2) conduct a time-course experiment to determine the effect(s) of challenging TSWV-exposed and non-exposed thrips with dsRNAs of F. occidentalis Dcr-2 or AGO2 by hemocoel injection, and 3) construct transgenic plants expressing a thrips-gene specific dsRNA hairpin to target a vital gene. My research has catalogued insect response to TSWV activity in thrips during development and provides candidate sequences for functional analysis of genes involved in insect development and defense. Successful silencing of the antiviral RNAi pathway in thrips revealed increased mortality and decreased offspring production in both virus-exposed and non-exposed insects. Arabidopsis plants were developed to express dsRNA of vacuolar ATP synthase (V-ATPase) and preliminary feeding bioassays to explore the effect of these transgenics on thrips fitness indicate a need for further description of thrips dsRNA uptake. In total, my research contributes new basic knowledge underpinning the complex and dynamic relationship between thrips vectors and the plant viruses they transmit.
38

The ecology of the South African citrus thrips, Scirtothrips aurantii Faure and its economic implications

Gilbert, Martin Jeffray January 1993 (has links)
The South African Citrus Thrips, Scirtothrips aurantii Faure (Thysanoptera: Thripidae) has been a serious pest of the citrus industry of Southern Africa for over 70 years. It is indigenous to Africa and has no recorded parasitoids and, in most citrus-growing regions, predators are not economically effective. Firstly, in this study, the general ecology of thrips was reviewed along with the recorded history of S. aurantii and its control. Host plant relationships of S. aurantii were then examined and wild hosts were not found to be important in promoting citrus thrips outbreaks in the orchard after flowering. In addition, Scirtothrips dorsalis Hood, which attacks citrus in Asia, was collected for the first time in Africa, but from Castor Oil plant. It is therefore a potential pest of citrus here. Notes on its appearance compared to that of S. aurantii were prepared. Weekly sampling of S. aurantii adults was carried out from June 1984 to May 1990. Population fluctuations were then correlated with phenology of the citrus trees and the direct and indirect effects of weather. Temperature and rainfall were not found to be significantly directly correlated with thrips numbers recorded. However, the indirect effects of rainfall were important in promoting a large winter thrips population in certain years. Relatively high rainfall during March and April compared to that of the previous January and February stimulated atypical flushing of the citrus trees during autumn and the setting of out-of-season fruit. S. aurantii then exploited this unusual food source and high numbers were subsequently recorded in the following winter; as well as in spring. Thus the mild winter climate alone could not suppress thrips numbers at Letaba. Dispersal/Emergence traps, which are used in the U.S.A. for the monitoring of Scirtothrips citri, were evaluated over 24 months, and were effective in recording population peaks of S. aurantii. The emergence rate of adults in relation to second instar larvae trapped was 43.7%. 35.7% of adults caught after emerging from the soil were males and 64.3 were females. In contrast, yellow traps had recorded 59.1% males and 40.9% females over the same period. The yellow traps were subsequently found to be biased towards male catches when young fruit and/or soft flush was present on the citrus trees. Relative inhibition of female flight activity during times of food abundance is known in other thrips species. During times of food scarcity, the bias in the yellow trap results disappeared. At Letaba Estates, availability of food rather than the direct effects of weather was seen to be the most important factor in governing S. aurantii numbers. Because of the importance of soft flush in the promotion of S. aurantii population increase, it is recommended that more attention should be given to the control of thrips on, as well as conducting surveys for, this food source. As the climate at Letaba is so favourable for citrus thrips, even during winter, it is further recommended that trapping for S. aurantii is carried out throughout the year. Furthermore, males and females should be recorded separately in trapping results as the sex ratio gives an indication of the phenological state of the tree.
39

Evolutionary relationships between pollination and protective mutualisms in the genus Macaranga (Euphorbiaceae) / オオバギ属植物(トウダイグサ科)における送粉共生と被食防衛共生の進化的関係

Yamasaki, Eri 24 March 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第18113号 / 理博第3991号 / 新制||理||1576(附属図書館) / 30971 / 京都大学大学院理学研究科生物科学専攻 / (主査)准教授 酒井 章子, 教授 山内 淳, 准教授 永益 英敏 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
40

A Synopsis of the Canadian Thysanoptera

Chiasson, Hélène January 1985 (has links)
Note: page 74 is missing from archival and circulating copies

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