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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.
11

Crescimento e produção de rúcula (Eruca Sativa L.) em função dos espaçamentos e da época de cultivo / Growth and productivity of arugula (Eruca Sativa L.) as a function of spaces and growing seasons

Gonçalves, Edilaine Della Valentina 22 February 2013 (has links)
Made available in DSpace on 2017-07-10T17:36:53Z (GMT). No. of bitstreams: 1 Edilaine_Della_Valentina_Goncalves.pdf: 1155715 bytes, checksum: bd6ed4706efb4fd4744ce4c15060dc2b (MD5) Previous issue date: 2013-02-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / With the goal of providing informations on the best growing season and the best spacing between plants and rows, and in order to achieve higher return and quality of arugula cv. Bella, two experiments were led in Unioeste Marechal Cândido Rondon PR. The first experiment was performed in spring 2011 and autumn and winter 2012, aiming of evaluate arugula‟s growth. The second experiment was realized over spring 2011 and summer, autumn and winter 2012, evaluating the productive performance of arugula‟s plant. The experimental delineation used was a randomized block with four replications in a 3x2 factorial arrangement. The first factor was consisted of three spacings‟ row (0.20, 0.25 and 0.30 m) and the second factor was consisted of two spacings between the plants (0.05 and 0.10 m). The cultivar used was Bella arugula. The first experiment: the highest value of leaf area and total leaf dry mass were obtained in the spring and winter seasons with spacing between row of 0.25 and 0.30 m and between plant‟s spacing of 0.10 m, so that on crops of autumn and winter seasons there was only seasonal effect to this feature. The specific leaf area was higher in spacing of plants with 0.10 m in the springtime, so that in autumn and winter there was only seasonal effect and obtained greater value for the variable in autumn. The absolute growth rate was influenced only by the spring season. In the autumn was verified effect of plants‟ spacings, with highest value of 0.10 m. During the winter crop there was effect of row spacings of 0.25 and 0.30 m and between plants of 0.10 m. These treatments have obtained better returns. About the relative growth rate there was effect in the spring and winter. The best results were obtained for the row spacing of 0.20 and 0.30 m during the autumn and presented a significant effect in plants of 0.10 m. Concerning the rate of net assimilation there was seasonal effect of the seasons of autumn and spring, with the greatest rate values obtained in autumn. The highest growth rate was obtained in plant spacing of 0.10 m. The sencond experiment: there was seasonal effect in plants‟ height, so that was verified taller plants in the spring and winter with values that did not differ statistically. The diameter of plants was higher in the winter, differing from the other seasons. The largest leaf area was noticed during the spring. The taller plants were found in plants‟ spacing of 0.05 m whose values differ from those verified in the spacing of 0.10 m. There was no difference in leaf area and diameter for different spacings. There was no difference in leaf area and diameter of plants for different plants‟ spacing. With regard to the row spacing was not found statistically significant differences for leaf area, leaf number and diameter plants. The unfolding of the interaction between seasons and spacings revealed that the highest number of leaves and total leaf fresh weight was obtained in plant spacing of 0.10 m and in the unfolding spacings in seasons, the highest average were obtained in the spring. Regarding productivity, the unfolding in spacings showed that the greater productivity in the spring, summer and winter was obtained in the spacing of 0.20 m, while the better cultivation spacing was 0.25 m in autumn. Unfolding the spacings in seasons, the best productivity results were obtained in the spring. The greatest productivity of arugula‟s cultivation was obtained in plants‟ spacings of 0.05 m / Com o objetivo de fornecer ao horticultor informações sobre a melhor época de cultivo e o melhor espaçamento entre plantas e entre linhas, visando obter maior rendimento e qualidade das plantas de rúcula cv. Bella foram conduzidos dois experimentos na Unioeste, Marechal Cândido Rondon-PR. O primeiro experimento foi conduzido na época de primavera/2011, outono e inverno/ 2012, visando avaliar o crescimento das plantas de rúcula. O segundo experimento foi conduzido durante a primavera/2011, verão, outono e inverno/2012, avaliando o desempenho produtivo da mesma. O delineamento experimental utilizado foi o de blocos casualizados, em esquema fatorial 3x2, com quatro repetições. O primeiro fator constituiu-se de três espaçamentos entre linhas (0,20; 0,25 e 0,30 m) e o segundo de dois espaçamentos entre plantas (0,05 e 0,10 m). A cultivar de rúcula utilizada foi a Bella. Primeiro experimento: os maiores valores de área foliar, massa seca total e foliar foram obtidas nas épocas de primavera e inverno e nos espaçamentos entre linhas de 0,25 e 0,30 m e entre plantas de 0,10 m. A maior razão de área foliar foi obtida no espaçamento entre plantas de 0,10 m na época de primavera, de modo que nos cultivos de outono e inverno houve somente efeito de época para esta característica. A área foliar especifica foi maior no espaçamento entre plantas de 0,10 m na época de primavera, de modo que no outono e inverno houve somente efeito de época, sendo no outono obtido maior valor para a variável. A taxa de crescimento absoluto foi influenciada somente pela época de primavera. No outono verificou-se efeito dos espaçamentos entre plantas, sendo o maior valor obtido no de 0,10 m. Durante o cultivo de inverno houve efeito dos espaçamentos entre linhas de 0,25 e 0,30 m e entre plantas de 0,10 m, sendo estes os tratamentos que obtiveram melhores resultados. Para a taxa de crescimento relativo verificou-se efeito das épocas de primavera e inverno. Na época de outono os melhores resultados foram verificados para os espaçamentos entre linhas de 0,20 e 0,30 m, que apresentou efeito significativo e entre plantas de 0,10 m. Com relação à taxa de assimilação líquida houve efeito das épocas de outono e primavera, sendo que os maiores valores da taxa foram obtidos na época de outono. A maior taxa de crescimento foi obtida no espaçamento entre plantas de 0,10 m. Segundo experimento: houve efeito da época para altura de plantas, sendo verificadas plantas mais altas na primavera e inverno, cujos valores não diferiram estatisticamente. O diâmetro das plantas foi maior no cultivo de inverno, diferindo das demais épocas. A maior área foliar das plantas foi verificada durante a época de primavera. As plantas mais altas foram encontradas no espaçamento entre plantas de 0,05 m, cujos valores diferiram dos observados no espaçamento de 0,10 m. Não houve diferença de área foliar e diâmetro de planta para os diferentes espaçamentos entre plantas. Com relação ao espaçamento entre linhas não foi verificado diferença estatística para área foliar, número de folhas e diâmetro das plantas. O desdobramento de épocas dentro de espaçamentos revelou que o maior número de folhas, massa fresca total e foliar foi obtida no espaçamento entre plantas de 0,10 m, e ao desdobrar os espaçamentos dentro de épocas, as maiores médias foram obtidas na primavera. Com relação à produtividade o desdobramento de épocas dentro de espaçamentos mostrou que a maior produtividade na primavera, verão e inverno foi obtida no espaçamento entre linhas de 0,20 m, enquanto que no cultivo de outono o melhor espaçamento para o cultivo de plantas de rúcula foi no de 0,25 m. Desdobrando espaçamentos dentro de épocas, os melhores resultados de produtividade foram obtidos na primavera. A maior produtividade da cultura de rúcula foi encontrada no espaçamento entre plantas de 0,05 m
12

The effect of field pea (<i>Pisum sativum </i> L.) basal branching on optimal plant density and crop competitiveness

Spies, Joshua Michael 09 April 2008
Field pea is an important crop in western Canada. The current recommended seeding rate in field pea is 88 plants m-2. As certain pea genotypes have the ability for increased branching, it may be possible for a producer to seed at a lower plant population without reduced yield or to choose a highly branched cultivar to have reduced risk of yield loss under conditions of poor emergence. The objective of this research was to determine how differences in branching among seven representative pea cultivars affected crop yield at different seeding rates, and to determine if branching affected the competitive ability of pea cultivars. In the plant population experiment, seven pea cultivars were seeded at five target plant populations (10, 30, 90, 120, and 150 plant m-2) during 2005 and 2006 at Rosthern and Saskatoon, Saskatchewan. The competition experiment involved eight cultivars being seeded at 50 plants m-2 to measure competitiveness with weeds. Plant emergence, number of branches, light interception, harvest index and grain yield were measured. Growth, seasonal temperature and rainfall were near normal in 2005. Severe terminal drought occurred in 2006 which may have lead to decreased yields. Branching was greatest at low plant densities and decreased as plant density increased. Grain yield increased as plant density increased until it plateaued at 80 100 plants m-2. The response of yield to plant density differed to some extent among cultivars, with CDC Acer and CDC Bronco achieving more of their potential yield at lower densities, while Carrera and Courier required higher densities to reach the same proportion of potential yield. Weed biomass was lowest in plots sown to longer vined cultivars with normal leaf type. Branching habit did not affect the competitiveness of pea cultivars. Potential exists to plant highly branched cultivars to reduce risk of yield loss in situations where low plant emergence might occur.
13

The effect of field pea (<i>Pisum sativum </i> L.) basal branching on optimal plant density and crop competitiveness

Spies, Joshua Michael 09 April 2008 (has links)
Field pea is an important crop in western Canada. The current recommended seeding rate in field pea is 88 plants m-2. As certain pea genotypes have the ability for increased branching, it may be possible for a producer to seed at a lower plant population without reduced yield or to choose a highly branched cultivar to have reduced risk of yield loss under conditions of poor emergence. The objective of this research was to determine how differences in branching among seven representative pea cultivars affected crop yield at different seeding rates, and to determine if branching affected the competitive ability of pea cultivars. In the plant population experiment, seven pea cultivars were seeded at five target plant populations (10, 30, 90, 120, and 150 plant m-2) during 2005 and 2006 at Rosthern and Saskatoon, Saskatchewan. The competition experiment involved eight cultivars being seeded at 50 plants m-2 to measure competitiveness with weeds. Plant emergence, number of branches, light interception, harvest index and grain yield were measured. Growth, seasonal temperature and rainfall were near normal in 2005. Severe terminal drought occurred in 2006 which may have lead to decreased yields. Branching was greatest at low plant densities and decreased as plant density increased. Grain yield increased as plant density increased until it plateaued at 80 100 plants m-2. The response of yield to plant density differed to some extent among cultivars, with CDC Acer and CDC Bronco achieving more of their potential yield at lower densities, while Carrera and Courier required higher densities to reach the same proportion of potential yield. Weed biomass was lowest in plots sown to longer vined cultivars with normal leaf type. Branching habit did not affect the competitiveness of pea cultivars. Potential exists to plant highly branched cultivars to reduce risk of yield loss in situations where low plant emergence might occur.
14

NOVEL CORN HYBRIDS FOR SILAGE PRODUCTION

Warren Whitaker, 01 January 2007 (has links)
Four corn (Zea mays) hybrid types at three plant densities and two nitrogen rates were evaluated for forage yield, forage quality and ensilage quality. The four hybrid types over the first two year of the study included nutri-dense, waxy, leafy, and dualpurpose, the third year a second dual purpose hybrid was added; while the three target plant densities were 54 000, 68 000, and 81 000 plants per hectare; and the nitrogen rates were 134 and 224 kilograms per hectare. The dual-purpose hybrid consistently had high forage yields compared with the other types. When averaged over nitrogen rate and hybrid type, the two highest plant densities typically had higher yields. Across all hybrids nitrogen had no effect on forage yield when averaged across plant density. The leafy hybrid had a lower harvest index than other hybrid types indicating that leaves accounted for much of the harvested weight. Hybrids were examined both at harvest (green chop) and after ensiling for protein and digestibility. Higher nitrogen rates increased crude protein when averaged over all hybrids and plant densities. Dual purpose and waxy hybrid types typically had the lowest acid detergent fiber (ADF) and neutral detergent fiber (NDF) and the highest relative feed values (RFV); while the nutri-dense and leafy hybrids typically had the highest ADF and NDF values and lowest RFV.
15

INFLUENCE OF VARIOUS PLANT POPULATIONS ON WEED REMOVAL TIMING IN GLYPHOSATE-RESISTANT SOYBEAN

Sarver, Jason 01 January 2009 (has links)
Reduced plant population in glyphosate-resistant soybean [Glycine max (L) Merr.] may influence the critical time of herbicide application. Field studies were conducted in 2007 and 2008 at two locations in Kentucky to determine the effect of four weed control programs on soybean seed yield, seed quality, crop canopy, and weed pressure when planted at three densities - 185,000, 309,000, and 432,000 plants ha-1. Plots were treated with glyphosate at either 3 weeks after planting (WAP), 5 WAP, 7 WAP, 3 & 7 WAP, representing common weed control protocols within the state. No differences in seed yield were discovered between plant densities in two of four siteyears. 254,500 plants ha-1 was sufficient for maximum yields in all site-years and was also sufficient to achieve maximum canopy amongst those populations tested in the study. Sequential applications at 3 and 7 WAP provided the highest seed yield, while the 5 WAP and 7 WAP application timings were generally the single applications that allowed for the highest yield and canopy closure, along with the highest visual estimate of weeds controlled. Plant density did not influence the critical period for weed control.
16

TWIN AND NARROW ROW WIDTH EFFECTS ON CORN (ZEA MAYS L.) YIELD AND WEED MANAGEMENT

Mackey, Grant 01 January 2013 (has links)
Corn or maize (Zea mays L.) has been grown in North America for many centuries, and an increase in corn production will continue to be needed. Agriculture producers must meet the demands of feeding and providing for an increasing population of people. In order to meet those needs, different production practices are being investigated as a way to increase grain yield. Field plots were conducted across the state of Kentucky in 2011 and 2012 to evaluate the interaction between hybrid, row width, and plant density on corn yield. The primary objectives were to test if 1) narrower rows increase grain yield, 2) higher plant densities increase yield in narrow and twin rows, and 3) the interactions among all factors. Three hybrids were evaluated in three row widths (76, 38 cm or twin) at target densities ranging from 74 000 to 124 000 plants ha-1. Interactions between hybrid, row width, and plant density occurred; however, effects on grain yield and plant physiological characteristics were small and variable across all environments. Plant density had the greatest impact on IPAR and grain yield. Field trials were conducted near Lexington and Princeton, Kentucky in 2011 and 2012 to evaluate the effects of row width on different weed management treatments in corn. The objectives were to 1) evaluate five weed management methods in three row widths (76, 38 cm or twin) and 2) estimate the effect of these practices on corn yield. Herbicides used within each weed management strategy included the residual herbicide S-metholachlor + atrazine (1.4 + 1.8 kg/ha) applied preemergence (PRE) and/or glyphosate (0.86 kg/ha) postemergence (POST). Weed management treatments consisted of a PRE only, PRE followed by POST, POST only, POST + PRE, and an untreated control. Row spacing had little effect on weed suppression and control except for two cases. In general, PRE followed by POST and POST + Residual treatments controlled weeds better compared to PRE only and POST only treatments. Corn yields were higher when a herbicide was used compared to applying no herbicide application. KEYWORDS: Row spacing, Plant Density, Corn Hybrids, Weed Management, Herbicide Application Timing
17

Produtividade de melância em função da adubação nitrogenada, potássica e população de plantas /

Feltrim, Anderson Luiz. January 2010 (has links)
Resumo: Foram conduzidos dois experimentos no período de 05/08/2009 a 31/10/2009, no município de Tupã-SP, cujas coordenadas geográficas são latitude 21º56'05" S, longitude 50º30'49" W e altitude de 524 metros, com objetivo de avaliar doses de N e K2O (79,8 e 106,7; 106,4 e 142,2; 133,0 e 177,7; 159,6 e 213,2 kg ha-1), via fertirrigação, e espaçamentos entre plantas (0,5; 1,0; 1,5 e 2,0 m) na produtividade de dois híbridos de melancia. Os híbridos utilizados foram Shadow e Top Gun, sem e com semente, respectivamente. O delineamento utilizado foi o de blocos casualizados, em parcela subdividida, com três repetições. Na parcela e na subparcela foram casualizadas doses de NK2O e espaçamentos para cada híbrido, respectivamente. O espaçamento entre as linhas foi de 2,0 m. As mudas foram formadas em bandejas com capacidade de 200 mudas e transplantadas quando apresentavam duas folhas. Foram avaliados os teores de nitrogênio e potássio na folha diagnóstico e na solução do solo, massa média de frutos, número de frutos e as produtividades total, comercial e classificação dos frutos, por planta e por área, para os dois híbridos. A dose de 79,8 kg ha-1 de N e 106,7 kg ha-1 de K2O, correspondente a 75% da dose de referência avaliada, é a recomendada para ser aplicada por fertirrigação tanto no híbrido Shadow como no híbrido Top Gun. O espaçamento de 0,5 m entre plantas proporcionou menor quantidade e produção de frutos por planta dos híbridos Shadow e Top Gun, com incremento significativo de quantidade de frutos e produção por área. Com o desenvolvimento da planta houve redução nas concentrações de nitrato e potássio na solução do solo / Abstract: Two experiments were conducted in the period from August 6 to October 31 of 2009, in Tupa, Sao Paulo State, Brazil, whose geographic coordinates are 21°56'05" S latitude, 50°30'49" W longitude and altitude of 524 meters, the objective of this work was to evaluate the doses of N and K2O (79.8 and 106.7, 106.4 and 142.2, 133.0 and 177.7, 159.6 and 213.2 kg ha-1) by fertigation and within-row plant spacing (0.5, 1.0, 1.5 and 2.0 m) in the productivity of two watermelon hybrids. The hybrids used were Shadow and Top Gun without and with seeds, respectively. The experimental design was randomized block in split-plot with three replications. The fertilizers doses were randomized at the plot, while the within-row spacing was randomized at the subplots. The row spacing was 2.0 m. The seedlings were formed in trays with capacity for 200 plants and transplanted when had two leaves. The variables evaluated were concentrations of nitrogen and potassium in the diagnosis leaf and in the soil solution, fruit mean mass, total and commercial fruit number, total and commercial productivity and classification of fruits per plant and per area of the two hybrids. The dose of 79.8 kg ha-1 N and 106.7 kg ha-1 K2O representing 75% of the reference dose evaluated it is recommended to be applied by fertigation in Shadow and Top Gun hybrids . The spacing of 0.5 m among plants provided a smaller amount and production per plant of Shadow and Top Gun hybrids with increased significantly in the amount of fruits and yield per area.The concentrations of nitrate and potassium in the soil solution decreased with the development of the plant / Orientador: Arthur Bernardes Cecílio Filho / Coorientador: Luiz Carlos Pavani / Coorientador: José Carlos Barbosa / Banca: Renato de Mello Prado / Banca: Mara Cristina Pessôa da Cruz / Banca: Roberto Lyra Villas Boas / Banca: Braulio Luciano Alves Rezende / Doutor
18

Caracterização de variedades de amendoim cultivadas em diferentes populações

Bulgarelli, Elisangela Maria Bernal [UNESP] 13 November 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-11-13Bitstream added on 2014-06-13T19:54:06Z : No. of bitstreams: 1 bulgarelli_emb_me_jabo.pdf: 236415 bytes, checksum: 527cf344cf8f231a39b406fdcbabe5e1 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Para obtenção de bons resultados de produtividade com menor custo, o uso do espaçamento entrelinhas e densidades de plantas na linha devem ser adequados, pois, a população de plantas é um dos fatores que se destacam por afetar diretamente os componentes de produção. Tendo em vista a escassez de informações relacionadas ao comportamento de variedades de amendoim, principalmente as rasteiras, cultivadas em diferentes populações, propôs-se no presente trabalho estudar os efeitos da densidade de plantas no desenvolvimento e produtividade do amendoim. Foram conduzidos três experimentos envolvendo três cultivares, sendo duas rasteiras Runner IAC 886 e IAC Caiapó e uma ereta IAC Tatu ST. Foram estudadas quatro densidades de plantas (22, 18, 12 e 6 plantas/m) mantendo-se o espaçamento entrelinhas em 0,90 m. Utilizou-se o delineamento em blocos ao acaso com quatro repetições, sendo a parcela experimental constituída de 7 linhas de 5 m de comprimento. Os resultados foram submetidos à análise de variância pelo teste F e as médias foram comparadas pelo teste de Tukey a 5% de probabilidade. As características relacionadas ao crescimento vegetativo foram pouco influenciadas pelas densidades de plantas. A cultivar Runner IAC 886 apresentou maior número de ramificações na menor densidade de plantas e a IAC Caiapó, apresentou maior comprimento de ramificações na maior densidade de plantas. Dentre as características relacionadas à produtividade, a mais afetada pela densidade de plantas foi o número de vagens por planta. A cultivar IAC Caiapó apresentou maior número de vagens por planta na menor densidade testada. As cultivares rasteiras Runner IAC 886 e IAC Caiapó apresentaram produtividades semelhantes nas diferentes densidades testadas e a ereta IAC Tatu ST, maiores produtividades nas maiores densidades de plantas. / The row spacing and plants density must be adequate for obtaining yield increases with lower costs, since the plants population is one of the main factors directly affecting the yield components. Once the information related to peanut varieties behavior in different populations is scarce, the aim of the present work was to study the effect of plants density on peanut yield and development. Experiments were carried out using three cultivars, the runner type ones Runner IAC 886 and IAC Caiapó and the bunch type IAC Tatu ST. Four plants density (22, 18, 12 and 6 plants per meter of row) were evaluated in 0.90 m row spacing. The randomized block design was used with four replicates, being the experimental plots composed by 7 rows of 5 m length each. Data were submitted to the variance analysis by the F test and means were compared by the Tukey test (5% probability). Traits related to vegetative growth were lightly affected by the different plants density. The higher plant branching was observed at the lower density for the Runner IAC 886 cultivar, while the IAC Caiapó showed higher plant branching at the higher density. Among the yield components, the number of pods per plant was the most affected trait by the plants density change. The IAC Caiapó cultivar showed the higher number of pods per plant at the lower tested density. Otherwise, the runner type cultivars Runner IAC 886 and IAC Caiapó showed similar results for yield at the different tested densities, whereas the bunch type IAC Tatu ST had higher yield at higher plants density.
19

Produtividade de melância em função da adubação nitrogenada, potássica e população de plantas

Feltrim, Anderson Luiz [UNESP] 20 January 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-01-20Bitstream added on 2014-06-13T19:04:50Z : No. of bitstreams: 1 feltrim_al_dr_jabo.pdf: 435086 bytes, checksum: ace9a4c65adff27ef33998e6a9e8c571 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Foram conduzidos dois experimentos no período de 05/08/2009 a 31/10/2009, no município de Tupã-SP, cujas coordenadas geográficas são latitude 21º56'05 S, longitude 50º30'49 W e altitude de 524 metros, com objetivo de avaliar doses de N e K2O (79,8 e 106,7; 106,4 e 142,2; 133,0 e 177,7; 159,6 e 213,2 kg ha-1), via fertirrigação, e espaçamentos entre plantas (0,5; 1,0; 1,5 e 2,0 m) na produtividade de dois híbridos de melancia. Os híbridos utilizados foram Shadow e Top Gun, sem e com semente, respectivamente. O delineamento utilizado foi o de blocos casualizados, em parcela subdividida, com três repetições. Na parcela e na subparcela foram casualizadas doses de NK2O e espaçamentos para cada híbrido, respectivamente. O espaçamento entre as linhas foi de 2,0 m. As mudas foram formadas em bandejas com capacidade de 200 mudas e transplantadas quando apresentavam duas folhas. Foram avaliados os teores de nitrogênio e potássio na folha diagnóstico e na solução do solo, massa média de frutos, número de frutos e as produtividades total, comercial e classificação dos frutos, por planta e por área, para os dois híbridos. A dose de 79,8 kg ha-1 de N e 106,7 kg ha-1 de K2O, correspondente a 75% da dose de referência avaliada, é a recomendada para ser aplicada por fertirrigação tanto no híbrido Shadow como no híbrido Top Gun. O espaçamento de 0,5 m entre plantas proporcionou menor quantidade e produção de frutos por planta dos híbridos Shadow e Top Gun, com incremento significativo de quantidade de frutos e produção por área. Com o desenvolvimento da planta houve redução nas concentrações de nitrato e potássio na solução do solo / Two experiments were conducted in the period from August 6 to October 31 of 2009, in Tupa, Sao Paulo State, Brazil, whose geographic coordinates are 21°56'05 S latitude, 50°30'49 W longitude and altitude of 524 meters, the objective of this work was to evaluate the doses of N and K2O (79.8 and 106.7, 106.4 and 142.2, 133.0 and 177.7, 159.6 and 213.2 kg ha-1) by fertigation and within-row plant spacing (0.5, 1.0, 1.5 and 2.0 m) in the productivity of two watermelon hybrids. The hybrids used were Shadow and Top Gun without and with seeds, respectively. The experimental design was randomized block in split-plot with three replications. The fertilizers doses were randomized at the plot, while the within-row spacing was randomized at the subplots. The row spacing was 2.0 m. The seedlings were formed in trays with capacity for 200 plants and transplanted when had two leaves. The variables evaluated were concentrations of nitrogen and potassium in the diagnosis leaf and in the soil solution, fruit mean mass, total and commercial fruit number, total and commercial productivity and classification of fruits per plant and per area of the two hybrids. The dose of 79.8 kg ha-1 N and 106.7 kg ha-1 K2O representing 75% of the reference dose evaluated it is recommended to be applied by fertigation in Shadow and Top Gun hybrids . The spacing of 0.5 m among plants provided a smaller amount and production per plant of Shadow and Top Gun hybrids with increased significantly in the amount of fruits and yield per area.The concentrations of nitrate and potassium in the soil solution decreased with the development of the plant
20

Influência das plantas daninhas na cultura do feijoeiro em função do espaçamento e da densidade de plantas

Parreira, Mariana Casari [UNESP] 22 June 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-06-22Bitstream added on 2014-06-13T19:37:09Z : No. of bitstreams: 1 parreira_mc_me_jabo.pdf: 280264 bytes, checksum: c5017d337f8118a62da5ed012e703826 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Objetivou-se determinar o período anterior à interferência das plantas daninhas em convivência com a cultura do feijoeiro, cultivar Carioca em resposta a densidade de semeadura e ao espaçamento entrelinhas. Os tratamentos foram constituídos de oito períodos de convivência da cultura com as plantas daninhas: 0-10, 0-20, 0-30, 0-40, 0-50, 0-60, 0-70 e 0-80 dias após a emergência e mais uma testemunha sem convívio com as plantas daninhas. Os períodos de convivência foram realizados em dois experimentos, utilizando dois espaçamentos, de 0,45 m e 0,60 m e em duas densidades de semeadura, de 10 e 15 plantas por metro. O delineamento experimental utilizado foi em blocos casualizados, com quatro repetições por tratamento. As espécies de maior importância relativa da comunidade infestante na área experimental foram: Acanthospermum hispidum, Cenchrus echinatus, Raphanus raphanistrum e Cyperus rotunduns. Houve redução de 16%, 40%, 36% e 58% na produtividade de grãos da cultura do feijoeiro quando em convivência durante todo o ciclo da cultura com as plantas daninhas, a produtividade de grãos passou a ser afetada negativamente a partir de 28, 22, 26 e 14 dias após emergência, constituindo-se nos períodos anteriores à interferência da cultura para o espaçamento de 0,45 m e densidades de semeadura de 10 e 15 plantas m-1; e espaçamento de 0,60 m e densidades de semeadura de 10 e 15 plantas m-1, respectivamente. / The research aim to determine the period prior to weed interference on common beans (Phaseolus vulgaris) ‘Carioca’. The treatments had been made out of eight periods of coexisting by the culture with the weed 0-10, 0-20, 0-30, 0-40, 0-50, 0- 60, 0-70 e 0-80 days after crop emergence the coexistence periods were done in two row spacing, with two seed density of 10 and 15 plants per meter. For each row spacing and seed density, the experimental delineation used was the randomized blocks, with four repetitions per treatment. The species of greatest importance on the weed community in the experimental area were: Acanthospermum hispidum, Cenchrus echinatus, Raphanus raphanistrum e Cyperus rotunduns. It had reduction of 16%, 40%, 36% and 58% the productivity of grains in the culture of the common bean when the coexistence with the weed was during all the cycle of the culture for row spacing of 0,45 m and seeding density of 10 and 15 plants per meter; and row spacing of 0,60 m and seeding density of 10 and 15 plants per meter, respectively. The period prior to weed interference (PPI) occurred in 28, 26, 22 e 14 days after crop emergence respectively.

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