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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.
1

Efeito de subdoses de maturadores de cana-de-açúcar na cultura do milho / Sublethal rates effect of sugarcane ripeners in maize

Felisberto, Patrícia Aparecida de Carvalho 23 February 2015 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-05-26T13:09:56Z No. of bitstreams: 2 Dissertação - Patrícia Aparecida de Carvalho Felisberto - 2015.pdf: 5137723 bytes, checksum: 1a2d107b747e1e556b5cc29325451197 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-05-26T13:14:03Z (GMT) No. of bitstreams: 2 Dissertação - Patrícia Aparecida de Carvalho Felisberto - 2015.pdf: 5137723 bytes, checksum: 1a2d107b747e1e556b5cc29325451197 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-05-26T13:14:03Z (GMT). No. of bitstreams: 2 Dissertação - Patrícia Aparecida de Carvalho Felisberto - 2015.pdf: 5137723 bytes, checksum: 1a2d107b747e1e556b5cc29325451197 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-02-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In the field aerial application of sugarcane ripeners, spraying should reach its target without drifting occurs, avoiding contamination of surrounding crops. The aim of this research was to evaluate the effects of sugarcane ripeners simulated drift using sublethal rates in maize when applied to V4 and V8 stages of development. For this purpose were installed two trials on the Federal University of Goiás, Regional Jataí. Each plot contained 10 rows of SYN 7G17 maize hybrid. Each trial consisted of eight treatments established in design with randomized blocks where the treatments were arranged at factorial design of 2 x 4, plus one control treatment, with four replications. First factor corresponds to spraying at the V4 and V8 stages of maize and the second factor to sublethal rates of 3; 6; 9 to 12% of 475.2 g a.i. ha-1 ethephon (Trial I), 216.0 g a.e. ha-1 glyphosate (Trial II) and 15.0 g a.i. ha-1 sulfometuron methyl (Trial III). At 20 and 36 days after sowing, when the maize were in V4 and V8, respectively, applications of ripeners were performed.The phytotoxicity effects were noticeable in both stages at 7, 14, 21, 28 and 42 days after spraying only for Trial III. For glyphosate, the length and diameter of ear were reduced in size to both stages. Maize is sensitive to sublethal rates starting from 0.45 g a.i. ha-1 sulfometuron methyl in V4 and V8 stages of development. The lower grain yield was only to plants subjected to sublethal doses of sulfometuron methyl, being lower yield when drift occurs in the V8 stage of development compared to the V4 stage. / Na aplicação aérea de maturadores de cana-de-açúcar, a pulverização deve atingir o seu alvo sem que ocorra deriva, evitando a contaminação de culturas circunvizinhas. Objetivou-se com a pesquisa avaliar o efeito de subdoses de maturadores de cana-de-açúcar na cultura do milho quando aplicadas em estádios de desenvolvimento V4 e V8. Foram instalados três ensaios na Fazenda da Universidade Federal de Goiás, UFG, Regional Jataí. Cada parcela continha 10 linhas do híbrido de milho SYN 7G17. Cada ensaio foi constituído de oito tratamentos estabelecidos em delineamento com blocos casualizados em esquema fatorial 2 x 4 mais um tratamento controle (sem aplicação de maturador), com quatro repetições. O primeiro fator corresponde a aplicação nos estádios V4 e V8 da cultura do milho e o segundo fator às subdoses de 3; 6; 9 e 12% de 475,2 g i.a. ha-1 de ethephon (Ensaio I), 216,0 g e.a. ha-1 de glyphosate (Ensaio II) e 15,0 g i.a. ha-1 de sulfometuron methyl (Ensaio III). Aos 20 e aos 36 dias após a semeadura, quando as plantas de milho se encontravam em V4 e V8, respectivamente, foram realizadas as aplicações dos maturadores. Os efeitos de fitotoxicidade foram perceptíveis em ambos os estádios aos 7, 14, 21, 28 e 42 dias após a aplicação apenas para o Ensaio III. Para glyphosate, o comprimento e diâmetro de espigas foram afetados para ambos os estádios. A cultura do milho é sensível a subdoses a partir de 0,45 g i.a. ha-1 de sulfometuron methyl em estádios de desenvolvimento V4 e V8. A produtividade de grãos foi menor apenas para as plantas submetidas às subdoses de sulfometuron methyl, com menos efeito quando a deriva ocorre no estádio de desenvolvimento V8 em comparação ao estádio V4.
2

Loblolly Pine Growth and Competition Response to Varied Chemical Site Preparation Treatments 14 Years After Establishment in the Piedmont of Virginia

Byers, Alexander M. 16 June 2021 (has links)
Chemical site preparation is used to enhance the productivity of loblolly pine plantations; however, it is most often combined with other methods and/or chemical release, and has been studied little on its own. Our study, conducted in the Virginia piedmont, compares the effects of various site preparation applications of imazapyr and their timings (July 23rd, September 3rd, and October 1st 2005) against a year-two chemical release (September 12th 2007), and an untreated check, all following a site preparation burn (June 15, 2005). Testing for additive effects, site preparation treatments were conducted with and without, sulfometuron methyl (SMAX) which targets herbaceous vegetation. Half of all treatments, including the check and release, received a year-one weed control treatment (H) of imazapyr and SMAX. Pines were measured every few years, including the latest measurement in year 14 (2019). Competing hardwood vegetation basal area was measured in year 14. All site preparation treatments reduced competition levels compared to the check, and an inverse relationship exists between competition level and pine volume. Adding SMAX resulted in less effective competition control, but had little effect on pine volumes. Adding H decreased average competition levels, and increased pine volumes. H treatments had the most effect at improving early season (July) applications. September and October treatments generally had more effect than July and the year-two release at controlling competing vegetation, and also showed higher individual pine tree volumes than all other treatments. Chemical site preparation treatments, even performed alone, appear to be valid means of improving pine stands. / Master of Science / Competing vegetation has a negative effect on planted pine production. Areas are often prepared with herbicides or mechanical removal of vegetation before crop-trees are planted (site preparation), or receive herbicide treatments after planting (release), to reduce levels of competition. Our study focuses on pre-planting herbicide (imazapyr with and without sulfometuron methyl) use at different timings (July 23rd, September 3rd, and October 1st). A chemical that targets herbaceous vegetation (sulfometuron methyl) was included in half of the pre-planting treatments, and half of all treatments, including the otherwise untreated check and year-two release, received an added weed control treatment in year-one. This was done to test for potential additive effects of chemical vegetation control options on pine productivity. September and October treatments have a greater effect at controlling competition 14 years since treatment and increasing pine volumes than the July, year-two release, and check. The added herbaceous control increased competition levels on average, without having an effect on the planted pine volumes. The year-one weed control decreased competition levels, and increased pine productivity, particularly within the July treatments. Overall, preparing sites with herbicide is beneficial to the pine stand, even when performed alone. Adding the herbaceous vegetation control is likely not necessary, and the extra year-one weed control may provide a boost to herbicide treatments applied earlier in the season.
3

Eficácia da mistura de glifosato a outros maturadores na cana-de-açúcar (Saccharum spp.)

Siqueira, Gabriela Ferraz de [UNESP] 28 August 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-08-28Bitstream added on 2014-06-13T19:07:35Z : No. of bitstreams: 1 siqueira_gf_me_botfca.pdf: 855761 bytes, checksum: 59ef306636208d8e19ab66bbdaa297ed (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A maturação natural, em início de safra, pode ser deficiente, mesmo em variedades precoces e o emprego de maturadores químicos destaca-se como uma ferramenta importante para antecipar o processo de maturação, promover melhorias na qualidade da matéria-prima a ser processada, otimizar os resultados agro-industriais e econômicos e auxiliar no planejamento da safra. Dentre os produtos utilizados, o glifosato é um dos que proporciona maior eficiência na antecipação da colheita, contudo, frequentemente diminui a rebrota da soqueira reduzindo a produtividade do canavial na safra posterior. Técnicos e produtores têm misturado o glifosato a outros maturadores, sem embasamento técnico-científico, acreditando melhorar a eficiência desses e como forma de redução de custo. O projeto teve por objetivo estudar a eficácia da mistura de glifosato a sulfometuron metil ou etil-trinexapac, e as alterações fisiológicas na cana-de-açúcar bem como suas implicações na produtividade, qualidade tecnológica e na rebrota da soqueira, em aplicação em início de safra. O projeto de pesquisa foi instalado e conduzido nos anos agrícolas de 2007 e 2008 em cana soca, em área pertencente ao GRUPO COSAN, Unidade Barra, no município de Igaraçu do Tietê, Estado de São Paulo. O delineamento experimental utilizado foi em blocos casualizados com cinco repetições. O experimento foi constituído de seis tratamentos: 1 – testemunha, sem aplicação de maturador, 2 - aplicação de glifosato (produto comercial Roundup), 3 - aplicação de sulfometuron metil (produto comercial Curavial), 4 - aplicação de etil-trinexapac (produto comercial Moddus), 5 - aplicação da mistura glifosato + sulfometuron metil e 6 - aplicação da mistura glifosato + etil-trinexapac. As doses... / The natural maturation, early harvest, may be poor, even in early varieties and the use of chemical ripeners stands out as an important tool to advance the maturation process, further improvements in the quality of raw material to be processed, optimize results agro-industrial and economic and assist in the planning of the harvest. Among the products used, glyphosate is one that provides greater efficiency in anticipation of the harvest, however, often reduces the regrowth of the ratoon cane reducing the productivity of sugarcane in crop later. Technicians and producers have mixed the glyphosate with other ripeners, without basement technical-scientific, believing to improve the efficiency and as to reduce costs. The project aimed to study the effectiveness of the mixture of glyphosate to sulfometuron methyl or ethyltrinexapac, and physiological changes in sugar cane and its implications on productivity, technological quality and in the regrowth of the ratoon cane in application beginning of the season. The study was installed and conducted in the years 2007 and 2008 in ratoon cane, in area belonging to the COSAN GROUP, Barra Unit, in Igaraçu do Tietê, São Paulo. The experimental design was in a randomized block design with five replications. Each experiment consisted of six treatments (1 - control, without application of ripener, 2 - application of glyphosate (commercial product Roundup), 3 - application of sulfometuron methyl (commercial product Curavial), 4 - application of ethyl-trinexapac (commercial product Moddus), 5 - application of the mixture glyphosate + sulfometuron methyl and 6 - application of the mixture glyphosate + ethyl-trinexapac. The doses were, respectively: 0,4 L c.p. ha-1, 20 g ha-1, 0,8 L c.p. ha-1, 0,2 L c.p. ha-1 + 15 g c.p. ha-1 e 0,2 L c.p. ha-1 + 0,5 g c.p. ha-1. The variety... (Complete abstract click electronic access below)
4

Eficácia da mistura de glifosato a outros maturadores na cana-de-açúcar (Saccharum spp.) /

Siqueira, Gabriela Ferraz de, 1980. January 2009 (has links)
Orientador: Carlos Alexandre Costa Crusciol / Banca: Marcelo de Almeida Silva / Banca: Raffaella Rossetto / Resumo: A maturação natural, em início de safra, pode ser deficiente, mesmo em variedades precoces e o emprego de maturadores químicos destaca-se como uma ferramenta importante para antecipar o processo de maturação, promover melhorias na qualidade da matéria-prima a ser processada, otimizar os resultados agro-industriais e econômicos e auxiliar no planejamento da safra. Dentre os produtos utilizados, o glifosato é um dos que proporciona maior eficiência na antecipação da colheita, contudo, frequentemente diminui a rebrota da soqueira reduzindo a produtividade do canavial na safra posterior. Técnicos e produtores têm misturado o glifosato a outros maturadores, sem embasamento técnico-científico, acreditando melhorar a eficiência desses e como forma de redução de custo. O projeto teve por objetivo estudar a eficácia da mistura de glifosato a sulfometuron metil ou etil-trinexapac, e as alterações fisiológicas na cana-de-açúcar bem como suas implicações na produtividade, qualidade tecnológica e na rebrota da soqueira, em aplicação em início de safra. O projeto de pesquisa foi instalado e conduzido nos anos agrícolas de 2007 e 2008 em cana soca, em área pertencente ao GRUPO COSAN, Unidade Barra, no município de Igaraçu do Tietê, Estado de São Paulo. O delineamento experimental utilizado foi em blocos casualizados com cinco repetições. O experimento foi constituído de seis tratamentos: 1 - testemunha, sem aplicação de maturador, 2 - aplicação de glifosato (produto comercial Roundup), 3 - aplicação de sulfometuron metil (produto comercial Curavial), 4 - aplicação de etil-trinexapac (produto comercial Moddus), 5 - aplicação da mistura glifosato + sulfometuron metil e 6 - aplicação da mistura glifosato + etil-trinexapac. As doses... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The natural maturation, early harvest, may be poor, even in early varieties and the use of chemical ripeners stands out as an important tool to advance the maturation process, further improvements in the quality of raw material to be processed, optimize results agro-industrial and economic and assist in the planning of the harvest. Among the products used, glyphosate is one that provides greater efficiency in anticipation of the harvest, however, often reduces the regrowth of the ratoon cane reducing the productivity of sugarcane in crop later. Technicians and producers have mixed the glyphosate with other ripeners, without basement technical-scientific, believing to improve the efficiency and as to reduce costs. The project aimed to study the effectiveness of the mixture of glyphosate to sulfometuron methyl or ethyltrinexapac, and physiological changes in sugar cane and its implications on productivity, technological quality and in the regrowth of the ratoon cane in application beginning of the season. The study was installed and conducted in the years 2007 and 2008 in ratoon cane, in area belonging to the COSAN GROUP, Barra Unit, in Igaraçu do Tietê, São Paulo. The experimental design was in a randomized block design with five replications. Each experiment consisted of six treatments (1 - control, without application of ripener, 2 - application of glyphosate (commercial product Roundup), 3 - application of sulfometuron methyl (commercial product Curavial), 4 - application of ethyl-trinexapac (commercial product Moddus), 5 - application of the mixture glyphosate + sulfometuron methyl and 6 - application of the mixture glyphosate + ethyl-trinexapac. The doses were, respectively: 0,4 L c.p. ha-1, 20 g ha-1, 0,8 L c.p. ha-1, 0,2 L c.p. ha-1 + 15 g c.p. ha-1 e 0,2 L c.p. ha-1 + 0,5 g c.p. ha-1. The variety... (Complete abstract click electronic access below) / Mestre

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