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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.
21

Avaliação de sistemas de manejo em Nitossolo Vermelho distroférrico e na cultura do girassol

Fernandes, Jairo Costa [UNESP] 01 December 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-12-01Bitstream added on 2014-06-13T19:41:53Z : No. of bitstreams: 1 fernandes_jc_dr_botfca.pdf: 1115073 bytes, checksum: 2801ee5f0b4afe076eb6fd7a690f282d (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O girassol é uma oleaginosa de reconhecida importância na alimentação animal, humana, sendo, atualmente, uma das principais matérias-prima para produção de biocombustível. Existem poucos estudos relacionados aos sistemas de manejo do solo adotados para esta cultura. Objetivou-se no presente trabalho quantificar e analisar os efeitos dos sistemas de manejo nos atributos físicos e químicos de um Nitossolo Vermelho Distroférrico (NVdf), após a colheita do girassol, em uma área cultivada durante 11 anos sob o sistema de semeadura direta, e identificar a velocidade na operação de semeadura que permite o melhor desenvolvimento do girassol. O experimento foi instalado na Fazenda Experimental do Lageado, pertencente à Faculdade de Ciências Agronômicas da UNESP, localizada no município de Botucatu-SP. O delineamento experimental foi em blocos ao acaso, seguindo o esquema de parcela subdividida, com quatro repetições. Os tratamentos efetuados nas parcelas foram: os sistemas de manejo do solo (semeadura direta com mecanismo sulcador tipo haste- SDh; semeadura direta com mecanismo sulcador tipo disco duplo-SDd; cultivo reduzido-CR e cultivo convencional-CC). Nas subparcelas, as velocidades utilizadas para a semeadura foram de 3; 5; 6 e 8 km h-1. Amostras de solo foram coletadas na camada superficial, após a colheita do girassol e analisou-se a textura do solo, densidades, porosidade, diâmetro médio ponderado, percentagem de agregados, resistência do solo à penetração e análise química do solo. Para o desempenho operacional dos equipamentos de preparos do solo e semeadura, foram analisadas as seguintes variáveis: velocidade de semeadura, patinagem das rodas motrizes, força média de tração na barra, resistência específica operacional, potência média de tração na barra, consumo horário e operacional de combustível, capacidade de campo teórica e área de solo... / The sunflower is an oleaginous plant of recognized importance in the animal and human feeding, being, at present, one of the main raw materials for bio-fuels production. There are few researches to the soil management systems for this crop. It was objectified in the present work to quantify and to analyze the effect of the management systems in the physical and chemical attributes of a Paleudult, after the harvest of the sunflower, in an area cultivated during 11 years under the system of direct sowing, identify the speed in the sowing operation that allows the best development in the productivity of the sunflower. The experiment was installed in “UNESP – São Paulo State University”, in the Experimental Farm of the Lageado of the Agronomic Sciences College- Botucatu-SP. The experimental was in randomized block design in split plot, with four repetitions. The effected treatments in the plots were: the soil management systems (no-till using furrow opener with mechanism type rod-SDh; no-till using furrow opener with mechanism type double disk-SDd record; minimum tillage-CR and conventional tillage-CC). In the sub plots, the used speeds for the sowing were 3; 5; 6 and 8 km h-1. Soil samples were collected in the surface layer, after the harvest of sunflower and analyzed to soil texture, density, porosity, mean weight diameter, percentage of aggregates, soil resistance to penetration and soil chemistry analysis. For the operational performance of equipment for soil preparation and seeding, were analyzed the following variables: speed of sowing, skating wheels driving, the average tensile strength in the bar, resistance specific operational, average power of the traction bar, time consumption and operational fuel, field capacity and theoretical area of soil mobilized. The variables of the culture of sunflower were evaluated: plant population, longitudinal distribution of plants... (Complete abstract click electronic access below)
22

Soybean Seeding Rate and Row Spacing Effects on Plant Establishment and Yield

Schmitz, Peder January 2018 (has links)
North Dakota soybean [Glycine max (L.) Merrill] management varies across the state, resulting in yield differences. Eight soybean seeding rates (starting at 197600 and increasing by 49400 live seed ha-1 increments) and row spacing (30 and 61 cm) were evaluated in 15 North Dakota environments in 2017-2018 to determine plant densities, seed yield, and plant loss, which were compared with soybean producer field data. Planting 30 cm row spacing yielded 183 kg ha-1 greater than 61 cm row spacing. On farm, maximum yields occurred at 414000 live seed ha-1 and final plant densities of 352000 plants ha-1. In research plots, 494000 live seed ha-1 had the highest yield. On farm, 8.9% plant loss occurred after plant establishment while research data observed 6.9% plant loss. North Dakota soybean producers should use narrow row spacing, use final plant density to estimate yields, and 444600 live seed ha-1 provided the highest net revenue. / North Central Soybean Research Program / North Dakota Soybean Council
23

Adaptive Vertical Farm for space farming

Bagnerini, Patrizia, Chnib, Echrak, Gaggero, Mauro, Zemouche, Ali 24 March 2023 (has links)
This work concerns a new concept of vertical farms that can be installed in orbital stations and future lunar settlements in order to produce fresh food for astronauts. The main novelty of this kind of greenhouse lies in the possibility of continuously adapting the volume assigned to each crop to the level of plant growth by automatically moving the shelves, thus allowing to grow a greater number of crops per unit of volume than existing solutions based on vertical farms with fixed shelves. The main results on the production yield estimation of this structure, compared to conventional vertical farms, are presented together with the prospect of future research work.
24

Overseeding Clovers into Permanent Pastures

Schlueter, David Henry 22 September 2011 (has links)
Benefits of establishing legumes into permanent pastures have been well studied. Successful establishment of legumes in pastures can be challenging, however, and more information is needed about different seeding methods and variables that affect legume establishment. A pasture and a small plot experiment were conducted in Blacksburg, Va from 2009 to 2011to gain better understanding of how seeding method and management variables affected red clover (Trifolium pratense L.) and white clover (Trifolium repens L.) establishment into permanent cool season grass pasture and sod. In the pasture experiment, seedling density was measured two months after sowing and grass, white clover, red clover, and weed biomass were periodically measured during the experiment. Broadcast seeding treatment had 93% more clover seedlings than drill treatment (P = 0.1087) two months after sowing. No difference (P > 0.10) for clover biomass was observed between sowing treatments in any year and clover establishment was considered successful (over 25% of pasture composition) in both treatments. In the drill treatment, clover seedling density was negatively affected by the residual grass biomass at sowing (P = 0.0196). In the broadcast treatment, a quadratic relationship between clover seedling density and residual grass biomass at sowing was found (P = 0.0516). Clover seedling density in April 2009 determined the amount of clover biomass in August 2009 (P = 0.0008) and the 2010 clover biomass mean (P = 0.0249). Further exploration of the influence fertilization with P and K, grass biomass at sowing, and defoliation frequency on clover establishment were studied in a split-split plot study. Fertilization with P and K was assigned to whole plots that were split in half and assigned a high or low grass biomass at sowing treatment, the subplots were split in and designated either a high or low cutting frequency. Prior to cutting, samples from each plot were sorted to grass, white clover, red clover, and weed. Plots with a low grass biomass at sowing (232 seedlings m-2) had a higher seedling density (P < 0.0001) compared with plots with a high grass biomass at sowing plots (111 seedlings m-2). Greater biomass of white and red clover depended both on having a low grass biomass at sowing and a high frequency of defoliation (P = 0.0026 and P < 0.0001, respectively). Red clover yield was also determined by interactions between fertilization and a high frequency of defoliation (P < 0.0001), as well as between fertilization and low grass biomass at sowing (P = 0.0026). Dry conditions resulted in low clover yields (6% of total herbage mass) with red clover producing four times the herbage mass of white clover. These data show that creating a favorable environment for seedlings to germinate and establish was more important than seeding method. / Master of Science
25

Caracteres morfológicos e produtivos do algodoeiro em diferentes configurações de semeadura / Morphologic and productive cotton characters indifferent sow configuration

Silva, Ariana Vieira 20 July 2007 (has links)
O presente estudo teve por objetivo avaliar o comportamento morfológico e produtivo da linhagem de algodão 96/319 sob espaçamentos ultra-adensado, adensado e convencional entre fileiras e número de plantas por metro linear. Os experimentos foram conduzidos em área experimental pertencente ao Instituto Agronômico de Campinas, município de Campinas e, em área agrícola no município de Leme, ambos no Estado de São Paulo, nos anos agrícolas de 1999/00 e 2000/01. O delineamento experimental foi o de blocos ao acaso em esquema fatorial, com 6 repetições, sendo três espaçamentos entre linhas (0,30, 0,60 e 0,90 m) e duas densidades de plantas por metro linear (7 e 10). Em cada parcela experimental foram marcadas quatro plantas ao acaso e analisados os seguintes parâmetros: altura média final das plantas, altura de inserção do 1º ramo frutífero, número de ramos vegetativos e reprodutivos e número de capulhos por planta. Na área útil de cada parcela foi determinada a produção de algodão em caroço e, em amostras de 20 capulhos por parcela, foram realizadas as análises dos caracteres agronômicos de laboratório (massa média de um capulho, massa de 100 sementes e porcentagem de fibra) e das características tecnológicas da fibra (comprimento, uniformidade de comprimento, tenacidade e micronaire e maturidade). De acordo com os dados experimentais obtidos, pôde-se concluir que: no espaçamento ultra-adensado, a produção de algodão em caroço foi, em média, 16% superior em relação ao espaçamento convencional; quanto à interação espaçamento entre linhas e densidade de plantas na linha, maior população de plantas resultam em menor número de capulhos por plantas e maior a produção de algodão em caroço por unidade de área; quanto menor o espaçamento entre linhas, maior a altura média final das plantas e o número de ramos vegetativos e, menor o número de ramos frutíferos e o número de capulhos por planta; quanto maior a densidade de plantas na linha, maior a altura de inserção do primeiro ramo frutífero e o número de ramos vegetativos; quanto menor o espaçamento entre linhas, menor a massa de um capulho, a massa de 100 sementes e a porcentagem de fibra; e, quanto maior a densidade de plantas na linha, menor a massa de um capulho; dentre as características tecnológicas da fibra, quanto menor o espaçamento, menor o índice micronaire e a maturidade da fibra. / The main objective of the present work was to study the morphological and productive behavior of cotton line 96/319 under ultra-narrow row, narrow row and conventional row and plants per linear meter. The experiments were carried out in an experimental area belonging to the Instituto Agronômico de Campinas, Campinas city and in commercial agricultural area in Leme city, both in São Paulo state, during the 1999/00 and 2000/01 season. The experimental design was in randomized blocks with six replications, three rows (0,30, 0,60 and 0,90 m between lines) and two densities (7 and 10 plants per linear meter). Four plants per plot were labeled and analyzed for the average plant height, insertion height of the first fruit branch, number of vegetative and fruit branches and open bolls per plant. The cotton yield was determinated in the useful area of each plot and samples of 20 open bolls randomized chosen per plot were analyzed for agronomical lab characteristics (average open boll mass, mass of 100 seeds and fiber percentage) and fiber technological characteristics (length, length uniformity, strength, micronaire and maturity). According to the experimental data obtained it was possible to conclude: cotton yield for the ultra-narrow was average 16% higher than the yields for the conventional row; for row and plant density interaction, higher plant population resulted smaller number of open bolls per plant and higher cotton yield per unit area; smaller row resulted higher average plant height and number of vegetative branches, and smaller number of fruit branches and open bolls per plant; higher plant density resulted higher insertion height of the first fruit branch and number of vegetative branches; smaller row resulted smaller average open boll mass, mass of 100 seeds and fiber percentage; and higher plant density resulted smaller average open boll mass; among fiber technological characteristics, smaller row resulted smaller micronaire and fiber maturity.
26

Rokovi i gustine setve u funkciji prinosa ozime pšenice u dugotrajnom poljskom ogledu / Sowing dates and densities in a function of winter wheat yield in the long-term field trial

Aćin Vladimir 08 December 2016 (has links)
<p>Vreme (rok) setve jedan je od najvažnijih faktora u proizvodnji strnih žita i praktično određuje intenzitet delovanja svih ostalih činilaca proizvodnje p&scaron;enice. Među brojnim faktorima koji određuju visinu prinosa, najče&scaron;ći uzrok malih prinosa ozime p&scaron;enice vezan je za vreme setve izvan optimalnog roka, upotreba neadekvatnih količina semena i izbor sorti nedovoljno prilagođenih datim agroekolo&scaron;kim uslovima. Osim toga, vreme setve predstavlja ekonomski najjeftiniju agrotehničku meru i najisplativiji način za povećanje prinosa zrna ozime p&scaron;enice, međutim eventualno ka&scaron;njenje u setvi ne može se na adekvatan način nadoknaditi ni jednom drugom agrotehničkom merom. Ekstremne vremenske prilike već predstavljaju izazov za proizvođače, a mnogobrojni klimatski scenariji predviđaju dalje povećanje njihove učestalosti u budućnosti. Upravo će u ovakvim promenljivim vremenskim uslovima optimalno vreme steve uz adekvatnu gustinu useva i izbor odgovarajućih genotipova biti od velike važnosti u cilju ublažavanja negativnog delovanja vremenskih činioca na visinu i stabilnost prinosa, kao i na tehnolo&scaron;ki kvalitet zrna ozime p&scaron;enice.<br />Prevashodni cilj istraživanja u disertaciji bio je proučavanje uticaja različitog vremena, gustina setve i njihove interakcije na prinos, komponente prinosa i kvalitet zrna različitih sorti p&scaron;enice. Istraživanje interakcije vremena, gustina setve i sorti ozime p&scaron;enice izvedeno je na oglednim poljima Instituta za ratarstvo i povrtarstvo na Rimskim &scaron;ančevima, u periodu od proizvodne 1981/82. do 2012/13. godine, na ogledu pod nazivom &bdquo;Rokovi setve&ldquo;. Ogled se postavlja svake godine, na zemlji&scaron;tu tipa karbonatni černozem, a izvodi se kao trofaktorijalni (Split-split-plot dizajn), u četiri ponavljanja, sa rasporedom varijanti po slučajnom blok sistemu.<br />Tokom 32-godi&scaron;njeg ispitivanog perioda, prinos zrna je znatno varirao u zavisnosti od vremenskih uslova i kretao se u proseku za sve tretmane od 4,35 t ha-1 u 2003., do 8,70 t ha-1 u 2013. godini. Na osnovu jednačine trenda prinosa, uočeno je da je godi&scaron;nje povećanje prinosa, u proseku za sve tretmane iznosilo 10,7 kg ha-1. Iz 32 analizirane godine izdvojeno je 5 godina sa najvećim prinosima, 12 godina sa malim prinosima p&scaron;enice, dok se preostalih 15 godina moglo označiti kao srednje rodne godine. U pogledu temperaturnih uslova i uslova vlažnosti u rodnim, srednje rodnim i nerodnim godinama postojale su značajne razlike između ovih grupa. U rodnim godinama, variranje prinosa u zavisnosti od rokova setve bilo je najmanje. Najveći prinos zrna, tokom posmatranog perioda, u proseku za sve ispitivane sorte i gustine setve ostvaren je setvom u II roku (11-20. X), i bio je značajno veći u odnosu na sve ostale rokove izuzev I roka. Između I i III roka, nije ostvarena statistički značajna razlika u visini prinosa, ali su prinosi u oba ova roka bili značajno veći u odnosu na novembarske i decembarski rok setve. Drugi rok odlikovao se najmanjim variranjem prinosa tokom istraživanog perioda. Novembarska setva smanjivala je prinos u proseku za 11%, a decembarska za 27%, u odnosu na prinose iz optimalnih agrotehničkih rokova. Prosečno dnevno smanjenje prinosa zrna iznosilo je 38 kg dan-1. Najmanje smanjenje prinosa prilikom ka&scaron;njenja u setvi bilo je u rodnim, zatim u srednjerodnim, a najveće u nerodnim godinama. U optimalnim rokovima setve (I i II rok) gustina od 500 kl. zrna m-2 bila je optimalna, dok je u kasnim rokovima (novembarskim i decembarskom), povećanje količine semena (do najvi&scaron;e 700 kl. zrna m-2),<br />imalo opravdanja. Odlaganje setve od I do V roka, uticalo je na povećanje sadržaja proteina, vlažnog glutena, moći upijanja vode, sedimentacionu vrednost, zapreminu i vrednosnog broja sredine hleba, kod obe sorte. Na osnovu prosečnih vrednosti za sve rokove setve, sorta Zvezdana ostvarila je bolje parametre kvaliteta u odnosu na NS 40S.</p> / <p>Sowing date is one of the most important field crop management measures in the production of small grains and it practically determines the intensity of all other factors in wheat production. Among many factors which determine yield, sowing outside the optimum period, use of inappropriate seed rates and selection of cultivars insufficiently adapted to a given agro-ecological conditions, are recognized as the most common causes of low yields of winter wheat. Moreover, sowing date is economically cheapest field crop management measure and a cost-effective way to increase grain yield. However, eventual delay in sowing cannot be adequately compensated by any other field crop management measure. Extreme weather events are already a significant challenge for grain producers and are predicted to increase under numerous future climate scenarios. In these altered weather conditions, optimal sowing date with an adequate sowing density and choice of appropriate genotypes will be of great importance in order to mitigate the negative effects of climate factors on yield stability, as well as on the bread making quality of winter wheat.<br />The aim of this research was to investigate the effects of different sowing dates, sowing densities and their interactions on yield, yield components and grain quality of different wheat cultivars. The study of interaction of sowing dates, sowing densities and cultivars of winter wheat was carried out on experimental fields of the Institute of Field and Vegetable Crops, in the 1981/82. &ndash; 2012/13. period. The experiment was set each year, on the calcareous chernozem soil, as a three factor trial (split-split-plot design), in four replications, with variants in the randomized block design.<br />During the 32-year studied period, grain yield has varied considerably depending on weather conditions and ranged from 4.35 t ha-1 in 2003., to 8.70 t ha-1 in 2013., on average for all treatments. It was observed that the annual increase in yields during the investigated period was 10.7 kg ha-1. From the 32 years analyzed there were 5 years with high yields, 12 years with low grain yields, while the remaining 15 years could be identified as a medium yielding years. There were significant differences in temperature regimes and moisture conditions between these three types of years. Yield variation caused by the different sowing date was much lower in high yielding in comparison to low yielding years. For the entire examined period, on average of all tested cultivars and planting densities, the highest grain yields were obtained in the II sowing date (11-20. X), and were significantly higher in comparison to all other sowing dates, except the earliest (I sowing date). There were no statistically significant differences in yields between I and III sowing date, but they were significantly higher in comparison to sowing in November and December. Second sowing date had the lowest yield variation during the studied period. Sowing in November reduced yield by 11% and December sowing by 27% on average, compared to optimal (October) sowing dates. During the investigated period, average daily reduction of grain yield was 38 kg day-1. The smallest decline in yields caused by the delay in sowing was in high yielding years, followed by medium yielding, and the largest yield decline was found in low yielding years. In the optimal sowing dates (I and II), a density of 500 viable kernels m-2 proved to be optimal, while in the later sowing dates (November and December), increasing the sowing density up to 700 viable kernels m-<br />2, was justified. Delay in sowing from I to V sowing date caused an increase in the bread-making quality parameters such as protein content, wet gluten content, water absorption capacity, Zeleny sedimentation value, bread loaf volume and value number of bread, for both cultivars examined. On average for all sowing dates and densities, cultivar Zvezdana achieved higher values for almost all bread-making quality parameters tested in comparison to NS 40S.</p>
27

Consórcio de milho com forrageiras: atributos físicos do solo e produtividade / Corn consortium with forage: attributes physical soil and productivity

Santos, Paulo Ricardo Alves dos January 2016 (has links)
SANTOS, Paulo Ricardo Alves dos. Consórcio de milho com forrageiras: atributos físicos do solo e produtividade. 2016. 84 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia Agrícola, Programa de Pós-Graduação em Engenharia Agrícola, Fortaleza, CE, 2016. / Submitted by demia Maia (demiamlm@gmail.com) on 2016-08-01T13:27:48Z No. of bitstreams: 1 2016_dis_prasantos.pdf: 1948037 bytes, checksum: e1770d22fe7e64bae84ffa607d041a49 (MD5) / Approved for entry into archive by demia Maia (demiamlm@gmail.com) on 2016-08-01T13:28:25Z (GMT) No. of bitstreams: 1 2016_dis_prasantos.pdf: 1948037 bytes, checksum: e1770d22fe7e64bae84ffa607d041a49 (MD5) / Made available in DSpace on 2016-08-01T13:28:25Z (GMT). No. of bitstreams: 1 2016_dis_prasantos.pdf: 1948037 bytes, checksum: e1770d22fe7e64bae84ffa607d041a49 (MD5) Previous issue date: 2016 / The intensification of agricultural production systems is increasing in the current agriculture. In this sense, the simultaneous planting forage to grain crops, constitutes an alternative in the intensification of the production system, which can increase or not the productivity of the main crop, and produce straw for mulching. In order to check the occurrence of changes in the physical properties of the soil and in corn yield and dry matter production due to the corn consortium / forage in two sowing dates, this study was conducted in the experimental area of the Department of Agricultural Engineering of the Federal University of Ceará. The design was used in a randomized block design in a factorial scheme (3x2) + 1 with four replications, totaling 28 experimental units. The treatments consisted of three forages: Brachiaria, Panicum maximum cv. Mombaça and Crotalaria spectabilis intercropped with maize in two of fodder sowing dates, between the lines of simultaneous sowing maize (season 1 - E1) and corn leading the V4 stage of corn (season 2 - E2), and the control. The results showed that intercropping maize / forage did not interfere in phytotechnical characteristics of corn, nor in productivity, however produced changes in soil physical properties when the day of sowing in season 1. Despite the changes that have occurred in the soil, they were not sufficient to enhance the productivity of maize, which could possibly be related assessments on only one crop cycle. But when the goal was the production of dry straw, it is concluded that fodder Brachiaria brizantha and Mombasa at the time 1 (E1) are recommended / A intensificação dos sistemas de produção agrícola é cada vez maior na atual agricultura. Nesse sentido, o plantio simultâneo de forrageiras com culturas produtoras de grãos, constitui em uma alternativa na intensificação do sistema de produção, que poderá incrementar ou não a produtividade da cultura principal, além de produzir palha para cobertura do solo. Com o objetivo de verificar a ocorrência de mudanças nas propriedades físicas do solo, bem como na produtividade do milho e produção de matéria seca em função do consórcio milho/forrageiras em duas épocas de semeadura, o presente trabalho foi conduzido na área experimental do Departamento de Engenharia Agrícola da Universidade Federal do Ceará. Foi utilizado o delineamento em blocos ao acaso, no esquema fatorial (3x2) + 1 com quatro repetições, totalizando 28 unidades experimentais. Os tratamentos foram constituídos por três forrageiras: Brachiaria brizantha, Panicum maximum cv. Mombaça e Crotalária spectabilis consorciadas com o milho em duas épocas de semeadura das forrageiras, na entrelinha do milho simultâneo a semeadura (época 1 – E1) e na entrelinha do milho no estádio V4 do milho (época 2 – E2), além da testemunha. Os resultados permitiram concluir que a consorciação milho/forrageiras não interferiram nas características fitotécnicas do milho, nem tampouco, na produtividade, porém proporcionaram modificações nas propriedades físicas do solo quando da realização da semeadura na época 1. Apesar das modificações ocorridas no solo, as mesmas não foram suficientes em incrementar a produtividade do milho, o que possivelmente pode estar relacionado as avaliações em apenas um ciclo da cultura. Já quando o objetivo foi a produção de matéria seca de palha, conclui-se que as forrageiras Brachiaria Brizantha e Mombaça na época 1 (E1) são recomendadas
28

Caracteres morfológicos e produtivos do algodoeiro em diferentes configurações de semeadura / Morphologic and productive cotton characters indifferent sow configuration

Ariana Vieira Silva 20 July 2007 (has links)
O presente estudo teve por objetivo avaliar o comportamento morfológico e produtivo da linhagem de algodão 96/319 sob espaçamentos ultra-adensado, adensado e convencional entre fileiras e número de plantas por metro linear. Os experimentos foram conduzidos em área experimental pertencente ao Instituto Agronômico de Campinas, município de Campinas e, em área agrícola no município de Leme, ambos no Estado de São Paulo, nos anos agrícolas de 1999/00 e 2000/01. O delineamento experimental foi o de blocos ao acaso em esquema fatorial, com 6 repetições, sendo três espaçamentos entre linhas (0,30, 0,60 e 0,90 m) e duas densidades de plantas por metro linear (7 e 10). Em cada parcela experimental foram marcadas quatro plantas ao acaso e analisados os seguintes parâmetros: altura média final das plantas, altura de inserção do 1º ramo frutífero, número de ramos vegetativos e reprodutivos e número de capulhos por planta. Na área útil de cada parcela foi determinada a produção de algodão em caroço e, em amostras de 20 capulhos por parcela, foram realizadas as análises dos caracteres agronômicos de laboratório (massa média de um capulho, massa de 100 sementes e porcentagem de fibra) e das características tecnológicas da fibra (comprimento, uniformidade de comprimento, tenacidade e micronaire e maturidade). De acordo com os dados experimentais obtidos, pôde-se concluir que: no espaçamento ultra-adensado, a produção de algodão em caroço foi, em média, 16% superior em relação ao espaçamento convencional; quanto à interação espaçamento entre linhas e densidade de plantas na linha, maior população de plantas resultam em menor número de capulhos por plantas e maior a produção de algodão em caroço por unidade de área; quanto menor o espaçamento entre linhas, maior a altura média final das plantas e o número de ramos vegetativos e, menor o número de ramos frutíferos e o número de capulhos por planta; quanto maior a densidade de plantas na linha, maior a altura de inserção do primeiro ramo frutífero e o número de ramos vegetativos; quanto menor o espaçamento entre linhas, menor a massa de um capulho, a massa de 100 sementes e a porcentagem de fibra; e, quanto maior a densidade de plantas na linha, menor a massa de um capulho; dentre as características tecnológicas da fibra, quanto menor o espaçamento, menor o índice micronaire e a maturidade da fibra. / The main objective of the present work was to study the morphological and productive behavior of cotton line 96/319 under ultra-narrow row, narrow row and conventional row and plants per linear meter. The experiments were carried out in an experimental area belonging to the Instituto Agronômico de Campinas, Campinas city and in commercial agricultural area in Leme city, both in São Paulo state, during the 1999/00 and 2000/01 season. The experimental design was in randomized blocks with six replications, three rows (0,30, 0,60 and 0,90 m between lines) and two densities (7 and 10 plants per linear meter). Four plants per plot were labeled and analyzed for the average plant height, insertion height of the first fruit branch, number of vegetative and fruit branches and open bolls per plant. The cotton yield was determinated in the useful area of each plot and samples of 20 open bolls randomized chosen per plot were analyzed for agronomical lab characteristics (average open boll mass, mass of 100 seeds and fiber percentage) and fiber technological characteristics (length, length uniformity, strength, micronaire and maturity). According to the experimental data obtained it was possible to conclude: cotton yield for the ultra-narrow was average 16% higher than the yields for the conventional row; for row and plant density interaction, higher plant population resulted smaller number of open bolls per plant and higher cotton yield per unit area; smaller row resulted higher average plant height and number of vegetative branches, and smaller number of fruit branches and open bolls per plant; higher plant density resulted higher insertion height of the first fruit branch and number of vegetative branches; smaller row resulted smaller average open boll mass, mass of 100 seeds and fiber percentage; and higher plant density resulted smaller average open boll mass; among fiber technological characteristics, smaller row resulted smaller micronaire and fiber maturity.
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Adubação nitrogenada e densidade de semeadura em soja / Nitrogen fertilization and plant population for soybean

Uhry, Daniel 19 February 2010 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / In cultivars with a cycle shorter than 120 days it is known that there is a relationship between the speed of canopy closure and the grain yield. Aiming at a better initial growing and consequently a quickest canopy closure the aim of this study was to determine the effect of starting rates in genetically modified soybean cultivars in the late sowing and with a cycle shorter than 120 days. Experiments have been performed during the 2009 late sowing in Santa Maria, RS, Brazil. The cultivars used were A 6001 RG, FUNDACEP 53RR and BMX Apolo RR in the sowing density of 250 and 500 thousand viable seeds ha-1. The applied nitrogen rates were 0, 15 and 30 kg of N ha-1 as urea. The experimental design was randomized blocks with four replications with cultivars in the main plot and sowing density in the subplots and nitrogen rates in the sub-subplots. The covering rate was evaluated in two different periods of the cycle, in the full flowering and grain filling period, yield components and grains yield. It was not possible to show the effect of the starting rate for any of the cultivars in the tested conditions. For the yield variable there were differences between populations and cultivars. In the average of the three cultivars the population of 500.000 plants ha-1 showed better productivity with 3068 kg versus 2821 kg ha-1 in 250.000. On the other hand, among the cultivars, FUNDACEP 53RR obtained better yield followed by BMX Apolo RR and A 6001 RG. The right choice of the genotype with more suitable sowing is fundamental for soybean to obtain higher yields in the late sowing in Rio Grande do Sul. / Nas cultivares com o ciclo menor de 120 dias sabe-se que existe uma relação entre a velocidade de fechamento do dossel e o rendimento de grãos. Visando a um melhor crescimento inicial e, por conseqüência um fechamento mais rápido do dossel, o objetivo deste trabalho foi determinar o efeito de doses de arranque em cultivares transgênicas de soja semeadas na safrinha e com ciclo menor do que 120 dias. Foram realizados experimentos durante a safrinha agrícola 2009, em Santa Maria/RS. As cultivares utilizadas foram A 6001 RG, FUNDACEP 53 RR e BMX Apolo RR nas densidades de semeadura de 250 e 500 mil sementes aptas ha-1. As doses de nitrogênio aplicadas foram 0, 15 e 30 Kg de N ha-1 na forma de uréia. O delineamento experimental foi o de blocos ao acaso e quatro repetições, sendo cultivares na parcela principal e densidade de semeadura nas subparcelas e doses de nitrogênio nas subsubparcelas. Foi avaliada a taxa de cobertura do solo pela cultura da emergência até a floração, índice de área foliar em dois momentos distintos do ciclo, no florescimento pleno e enchimento de grãos, componentes do rendimento e rendimento de grãos. Não foi possível evidenciar o efeito de dose de arranque para nenhuma das cultivares nas condições testadas. Para a variável rendimento ocorreu diferenças entre populações e entre cultivares. Na média das três cultivares a população de 500.000 plantas ha-1 apresentou melhor produtividade com 3068 kg ha-1 contra 2821 kg ha-1 em 250.000. Já entre as cultivares, a FUNDACEP 53RR obteve melhor rendimento, seguida da BMX Apolo RR e A 6001 RG. A escolha correta do genótipo com a densidade de semeadura mais apropriada, é primordial para que a soja possa obter rendimentos mais elevados na safrinha no Rio Grande do Sul.
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Metody a možnosti regulace plevelů v jarních obilninách

DVOŘÁK, Jan January 2019 (has links)
The thesis focused on description and characteristics of spring wheat and barley and their life cycles. Thesis deals with the issue of very dangerous weed plants and deals with the possibilities of their regulation by using herbicidal preparations in the growth spring cereals. Weeds are problematic plants that negatively affect the quality of production and also the economy of cultivation. Part of the thesis is the evaluation of a small plot experiment, which was performed in the crop of the spring barley on the land of the company AGRO Dolní Bukovsko in the cadastral area of the village Sedlíkovice in the direction (of Veselí nad Lužnicí) and in the spring wheat on the land of the above mentioned company in the cadastral territory of the municipality of Radonice in year 2017. Results of weed frequency and economic evaluation of the experiment are presented in tables and graphs.

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