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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

Produtividade e qualidade de brócolos em função da adubação e espaçamento entre plantas /

Schiavon Júnior, Aparecido Alecio. January 2008 (has links)
Orientador: Arthur Bernardes Cecílio Filho / Banca: Paulo Espíndola Trani / Banca: laila Trevisan Braz / Resumo: No município de Itatiba-SP, no período de março a julho de 2007, foi realizado um experimento,com o objetivo de avaliar o efeito de doses de nitrogênio e potássioe espaçamento entre plantas na produtividade de brócolos. O experimento foi instalado sob delineamento de blocos ao acaso, com os tratamentos em esquema fatorial 5 x 4, e três repetições, sendo avaliadas as doses de nitrogênio-potássio: 105- 105; 157,5-157,5;210-210; 262,5-262,5 e 315-315 kg ha-1N-K20 e os espaçamentos entreplantas: 0,20; 0,30; 0,40 e 0,50 m. O espaçamento entre linhas foi de 0,80 m. As variáveis avaliadas foram: teor de nitrogênio e de potássio na folha diagnóstica do estado nutricional, massa seca do caule, massa seca da folha, área foliar, diâmetro do caulena inserção da inflorescência, comprimento do caule, distúrbios fisiológicos (caule oco, brotação lateral, folhas na cabeça e olho de gato), ciclo, massa fresca da inflorescência, produtividadede inflorescência, diâmetro da inflorescência, classificação da inflorescência (classe 10 (C1O):S 10 cm; classe 13 (C1013): > 10 e S 13 cm; classe 16 (C1316):> 13 e S 16cm; classe 19 (C1619):> 16 e S 19 cm; classe 22 (C1922): > 19 e s 22 cm e classe 25 (C2225):> 22 e S 25 cm), produtividadede floretes, classificaçãodos floretes (PF5 (S 5 cm); PF57 (> 5 e S 7 cm); PF79 (> 7 e S 9 cm) e PF9(> 9 cm)) e rendimento industrial. A menor densidade de plantio proporcionou o maior teor de nitrogênio, massa seca do caule, massa seca da folha, área foliar, diâmetrodo caule na inserção da inflorescência, os distúrbios fisiológicos caule oco e folhasna cabeça, massa fresca da inflorescência, número de inflorescência na classe 19. Enquanto que, o comprimento do caule, ciclo, produtividade de inflorescências, númerode inflorescência nas classes 10 e 13, produtividade de floretes, percentagem de floretes na classe PF5 foram obtidos no menor espaçamento entre plantas. / Abstract: In Itatiba eity, SP state, during the period between Mareh and July of 2007,a study was carried out aiming to appraise the effeet of doses of nitrogen and potassium and spacing between plants on the productivity of broccoli. The experiment was carried out in a randomized block design, with the treatments in a 5 x 4 factorial seheme and three repliections. The following treatments were studied: doses of nitrogen-potassium of 105-105, 157.5-157.5,210-210, 262.5-262.5 and 315-315 kg ha-1 N-K20;the spacing between plants were 0.20, 0.30, 0.40 and 0.50 m. Rows of plants were 0.80 m apart. The characteristics evaluated were: levels of nitrogen and potassium in leaves, stem dry weight, leaf dry weight, leaf area, stem diameter at the height of infloreseenee,stem length, physiologieal disturbanees (hollow stem, lateral budding, leaveson head and eat's eye), eycle, fresh weight of infloreseenee, head produetivity, diameterof infloreseenee,elassifieationof infloreseeneebased on diameter (S 10 em; > 10and S 13 em; > 13 and S 16em; > 16 and S 19 em; > 19 and S 22 em; and > 22 and S 25 em), produetivity of florets based on length (S5 em; > 5 and S 7 em; > 7 and S 9 em; and > 9 em) and eommercial yield. The largest spaeing between plants provided the highest nitrogen level, stem dry weight, leaf dry weight, leaf area, stem diameter at the height of inflorescence, the physiological disturbances hollow stem and leaves in head, fresh weight of inflorescence and inflorescences with diameter> 16 and <= 19 cm. On the other hand, stem length, cycle, head productivity, number of inflorescences<= 13 cm, productivity of florets and percentage of florets in class < 5 cm were obtained with smaller spacing between plants. The maximalhead productivity was 22,082 kg ha-1, obtained with 0.20 m between plants and 150% N-K20 dose (315 kg ha-1 of N and K20). / Mestre
22

Caracteres morfológicos e produtivos da palma forrageira cv. miúda em diferentes sistemas de cultivo

OLIVEIRA, Cristiane Gomes da Silva 29 April 2015 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-03-31T14:10:26Z No. of bitstreams: 1 Cristiane Gomes da Silva Oliveira.pdf: 1111052 bytes, checksum: baa496b92be175b9301405ec24ef15ed (MD5) / Made available in DSpace on 2017-03-31T14:10:26Z (GMT). No. of bitstreams: 1 Cristiane Gomes da Silva Oliveira.pdf: 1111052 bytes, checksum: baa496b92be175b9301405ec24ef15ed (MD5) Previous issue date: 2015-04-29 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The cactus is a culture quite adapted to the climatic conditions of the arid and semiarid regions of northeastern Brazil. However, its production can be affected by several management factors, such as planting density, fertilizing, cutting intensity and other factors. The objective was to evaluate the morphological and productive characteristics of the forage cactus cv. (small) on different cropping systems. The assessments were performed in two experiments conducted at the Experimental Station José Nilson de Melo belonging to Agronomic Institute of Pernambuco (IPA), located in City of Caruaru-PE. In Experiment 1, the cactus cv (small) was cultivated under different planting densities and cutting intensities in randomized block design with a split-plot experimental arrangement, with four repeats, in the period from January to September 2014.The main plot was formed by planting densities (10,417; 20,833; 41,666 e 83,333 plants há-1) and the subplots, by cutting intensities (preservation of primary or secondary cladodes). In Experiment 1, was evaluated levels of organic and mineral fertilizing, in randomized block design with a split-plot experimental arrangement. The main plot was evaluated in terms of organic fertilizer levels of (0, 10, 20 e 30 OM t/ha/year) and subplots, for the nitrogen chemical fertilization levels of (0, 120, 240 e 360 kg N/ha/year) with four repeats from October 2013 to October 2014. In both experiments, the traits evaluated were height and width of the plant, number of cladodes per plant and per order, dimensions of cladodes (length, width, perimeter and thickness), productivity (DMP) t DM/ha-1year-1and the cladode area index (CAI). In experiment 1, greater heights (68.3 cm) and width (80.8 cm) were obtained in plants which cutting intensities based on the preservation of the secondary cladodes. Increased planting density caused a linear reduction in the number of cladodes per plant to the two cutting intensities tested. Increasing the evaluation period led to increments in the morphological characteristics of the spineless cactus. There were no effects (P <0.05) of the treatments for the number of primary cladodes. The higher plant density (83,333 plants ha -1) provided an increase in cladode area index and productivity. In experiment 2, there was no effect of nitrogen fertilization for the variables studied. The number of cladodes/plant ranged from 4.5 to 9.3 in the treatments with 0 to 30 t OM ha-1yr-1of organic fertilizer-1, respectively. The evaluation period also had a positive influence on the number of cladodes per plant. Increased levels of organic fertilization increased the number of primary cladodes quadratically. To the number of secondary cladode there was effect of interaction between organic fertilizer and evaluation period. The dimensions of the cladodes were positively influenced by the interaction between organic fertilizer and evaluation period. The organic fertilization with 30 t ha OM-1 yr-1 increased the height and width of the plant to 50.3 cm and 40.2 cm, respectively. Was observed CAI of 0.48 and 1.0 in the treatments with 0 to 30 t ha-1 OM y-1 respectively. For DMP was observed quadratic effect, with an increments in the production until the organic fertilization level of 20 t ha-1 yr MO-1, with 3.8 t DM / ha-1yr-1. / A palma forrageira é uma cultura bem adaptada às condições climáticas das regiões áridas e semiáridas do Nordeste brasileiro. Porém, a sua produção pode ser afetada por diversos fatores de manejo como, densidade de plantio, adubação e intensidade de corte, entre outros. Objetivou-se avaliar as características morfológicas e produtivas da palma forrageira cv. Miúda em diferentes sistemas de cultivo. Foram realizadas avaliações em dois experimentos conduzidos na Estação Experimental José Nilson de Melo, pertencente ao Instituto Agronômico de Pernambuco (IPA), localizada na cidade de Caruaru-PE. No experimento 1, a palma Miúda foi cultivada sob diferentes densidades de plantio e intensidades de corte, em delineamento casualizado em blocos com arranjo experimental de parcelas subdivididas, com quatro repetições, no período de janeiro a setembro de 2014. A parcela principal foi formada pelas densidades de plantio (10.417; 20.833; 41.666 e 83.333 plantas ha-1) e as subparcelas, pelas intensidades de corte (preservação de cladódios primários ou secundários). No experimento 2, avaliaram-se níveis de adubação orgânica e mineral, em delineamento casualizado em blocos com arranjo experimental de parcela subdividida, em que na parcela principal foi avaliado níveis de adubação orgânica (0, 10, 20 e 30 t/ha/ano) e na subparcela, os níveis de adubação nitrogenada (0, 120, 240 e 360 kg N/ha/ano) com quatro repetições, no período de outubro de 2013 a outubro de 2014. Em ambos os experimentos, os caracteres avaliados foram altura e largura da planta, número de cladódios por planta e por ordem, dimensões dos cladódios (comprimento, largura, perímetro e espessura), produtividade (PMS) t MS/ha-1 ano-1 e o índice de área de cladódio (IAC). No experimento 1, maiores alturas (68,3 cm) e larguras (80,8 cm) de plantas foram obtidas na intensidade em que se preservaram os cladódios secundários. O aumento da densidade de plantio causou uma redução linear no número de cladódios por planta, nas duas intensidades de corte avaliadas. O aumento do período de avaliação proporcionou aumento nas características morfológicas da planta. Não foram observados efeitos (P<0,05) dos tratamentos para o número de cladódios primários. A maior densidade de plantio (83.333 plantas ha-1) proporcionou aumento no índice de área de cladódio e na produtividade. No experimento 2, não houve efeito da adubação nitrogenada para as variáveis estudadas. O nº de cladódios/planta variou de 4,5 a 9,3 no tratamento com 0 e 30 t MO ha-1 ano-1, respectivamente. O período de avaliação também influenciou positivamente sobre o número de cladódios por planta. O aumento das doses de matéria orgânica elevou o nº de cladódios primários de forma quadrática. Para o nº de cladódios secundários foi observado efeito de interação entre a adubação orgânica e período de avaliação. As dimensões dos cladódios foram positivamente influenciadas pela interação entre adubação orgânica e período de avaliação. A adubação orgânica com 30 t MO ha-1 ano-1 elevou a altura e largura da planta para 50,3 cm e 40,2 cm, respectivamente. Foram obtidos IAC de 0,48 e 1,0 no tratamento com 0 e 30 t MO ha-1 ano-1, respectivamente. Para a PMS foi observado efeito quadrático, com acréscimo na produção até a dose de 20 t de MO ha-1 ano-1, com 3,8 t MS/ha-1ano-1.
23

Morphological and physiological responses of spring wheat (Triticum aestivum L.) to spatial arrangements

Tolmay, John Peter Cleggenett 12 1900 (has links)
Thesis (PhD(Agric) (Agronomy))--Stellenbosch University, 2008. / The adoption of the no-till planting method brought about changes to the way the wheat crop is established in the Mediterranean climate of the Western Cape. Row widths have to increase from the normal narrow rows (170-180 mm) to at least 250 mm to allow for sufficient stubble handling. Furthermore, planters are designed to place seed accurately in the soil at uniform depth, which may increase seedling survival rates. The main objective of this study was to determine the influence of the use of wide row widths on yield, the components of yield and grain quality parameters and to revisit planting density recommendations to be used with the notill planting method. On-farm, producer managed trials which included cultivars, row widths and planting density treatments were planted at Riversdale, Swellendam and Caledon in the Southern Cape region and at Moorreesburg and Hopefield in the Swartland during the 2004 to 2006 production seasons. All trials were factorial RCB designs with split-split plot arrangements. Grain yield, grain protein, hectolitre mass (HLM) and the yield components, seedlings m-2, seedling survival (%), number of heads m-2, number of heads plant-1, number of kernels head-1 and thousand kernel mass (TKM) were determined at all sites in 2005 and 2006. Seedling survival rates of 80% were easily achieved in all trials with the exception of Caledon and Swellendam in 2005. The no-till planting method may be efficient to improve on survival rates of 50-70% found with the conventional planting methods. The yield component response that raised the most concern was the clear trend of the reduction in the number of heads m-2 as row widths increased, which was significant in eight out of the nine experiments. The number of heads plant-1 decreased significantly as planting density increased in all experiments. Cultivars differed in the grain quality parameters grain protein (%) and HLM but were influenced minimally by the other treatments. Reductions in grain yield occurred in three out of eight trials in the Southern Cape and in three out of six trials in the Swartland, with reductions of between 6.8% and 33% in some seasons. The risk of yield loss due to wide row widths could not be excluded by this study and therefore the row widths used by producers should remain as narrow as practically possible. Grain yield response to increasing planting density differed between the two regions. No significant yield benefits were found in any of these trials if planting densities were increased above 175 target plants m-2. Planting densities may be reduced to between 70 and 87.5 kg seed ha-1 to achieve this target if the crop is planted in time and seedling survival rates of at least 80% can be achieved.
24

Produção e qualidade de cultivares de alface americana em função do espaçamento de plantio / Production and quality of lettuce cultivars as a function of planting spacing

Medeiros, Felipe Bruno Araújo de 16 March 2015 (has links)
Made available in DSpace on 2016-08-12T19:15:33Z (GMT). No. of bitstreams: 1 FelipeBAM_DISSERT.pdf: 755090 bytes, checksum: 07907a158d8ff73e0317a12403354630 (MD5) Previous issue date: 2015-03-16 / The lettuce when grown at high temperature and light conditions, fails to express all their genetic potential, with a reduction of the cycle and advance the reproductive stage. These conditions contribute to low productivity and lower quality of this vegetable. In order to assess the quality and yield performance of lettuce cultivars as a function of planting spacing, an experiment was conducted from August to October 2014, in Horta's Departamento de Ciências Vegetais, in Universidade Federal Rural do Semi-Árido, Mossoró/RN. The experimental design was a randomized complete block design with four replications in a factorial 3 x 4. The treatments consisted of the combination of three lettuce cultivars (Amelia, Angelina and Taina) and four planting spacing (15 x 15 cm, 20 x 20 cm, 25 cm and 30 x 25 x 30 cm). Production and quality characteristics were evaluated: average plant height (cm), medium plants diameter (cm), number of leaves per plant, fresh weight of aerial parts (g plant-1), dry weight of shoots (g plant -1), productivity (t ha-1), soluble solids (%), titratable acidity (%), soluble solids / titratable acidity, pH and total soluble sugars (%). The cultivars showed similar yields, with an average of 9,58 t ha-1. The reduction in planting spacing resulted in increased productivity without, however, interfere with the fresh mass of plants. The cultivars showed similarity in titratable acidity and soluble solids/titratable acidity, soluble solids while for Amelia and Angelina proved superior to Taina. The soluble solids and soluble solids/titratable acidity increased by planting spacing / A alface quando cultivada em condições de temperatura e luminosidade elevadas, deixa de manifestar todo seu potencial genético, havendo redução do ciclo e antecipação da fase reprodutiva. Essas condições concorrem para uma baixa produtividade e menor qualidade desta hortaliça. Com o objetivo de avaliar o desempenho produtivo e qualitativo de cultivares de alface americana em função do espaçamento de plantio, foi desenvolvido um experimento no período de agosto a outubro de 2014, na Horta do Departamento de Ciências Vegetais na Universidade Federal Rural do Semi-Árido em Mossoró, RN. O delineamento experimental usado foi o de blocos casualizados com quatro repetições, em esquema fatorial 3 x 4. Os tratamentos consistiram da combinação de três cultivares de alface americana (Amélia, Angelina e Tainá) e quatro espaçamentos de plantio (15 x 15 cm, 20 x 20 cm, 25 x 25 cm e 30 x 30 cm). Foram avaliadas características de produção e qualidade: altura média de plantas (cm), diâmetro médio de plantas (cm), número de folhas por planta, massa fresca da parte aérea (g planta-1), massa seca da parte aérea (g planta-1), produtividade (t ha-1), sólidos solúveis (%), acidez titulável (%), relação sólidos solúveis/acidez titulável, pH e açúcares solúveis totais (%). As cultivares apresentaram produtividades semelhantes, com uma média de 9,58 t ha-1. A redução no espaçamento de plantio resultou em maior produtividade sem, no entanto, interferir na massa fresca das plantas. As cultivares demonstraram semelhança quanto à acidez titulável e a relação sólidos solúveis/acidez titulável, enquanto para sólidos solúveis, Amélia e Angelina mostraram-se superiores à Tainá. Os sólidos solúveis e a relação sólidos solúveis/acidez titulável aumentaram com o espaçamento de plantio
25

Produção e qualidade de cultivares de alface americana em função do espaçamento de plantio / Production and quality of lettuce cultivars as a function of planting spacing

Medeiros, Felipe Bruno Araújo de 16 March 2015 (has links)
Made available in DSpace on 2016-08-12T19:18:50Z (GMT). No. of bitstreams: 1 FelipeBAM_DISSERT.pdf: 755090 bytes, checksum: 07907a158d8ff73e0317a12403354630 (MD5) Previous issue date: 2015-03-16 / The lettuce when grown at high temperature and light conditions, fails to express all their genetic potential, with a reduction of the cycle and advance the reproductive stage. These conditions contribute to low productivity and lower quality of this vegetable. In order to assess the quality and yield performance of lettuce cultivars as a function of planting spacing, an experiment was conducted from August to October 2014, in Horta's Departamento de Ciências Vegetais, in Universidade Federal Rural do Semi-Árido, Mossoró/RN. The experimental design was a randomized complete block design with four replications in a factorial 3 x 4. The treatments consisted of the combination of three lettuce cultivars (Amelia, Angelina and Taina) and four planting spacing (15 x 15 cm, 20 x 20 cm, 25 cm and 30 x 25 x 30 cm). Production and quality characteristics were evaluated: average plant height (cm), medium plants diameter (cm), number of leaves per plant, fresh weight of aerial parts (g plant-1), dry weight of shoots (g plant -1), productivity (t ha-1), soluble solids (%), titratable acidity (%), soluble solids / titratable acidity, pH and total soluble sugars (%). The cultivars showed similar yields, with an average of 9,58 t ha-1. The reduction in planting spacing resulted in increased productivity without, however, interfere with the fresh mass of plants. The cultivars showed similarity in titratable acidity and soluble solids/titratable acidity, soluble solids while for Amelia and Angelina proved superior to Taina. The soluble solids and soluble solids/titratable acidity increased by planting spacing / A alface quando cultivada em condições de temperatura e luminosidade elevadas, deixa de manifestar todo seu potencial genético, havendo redução do ciclo e antecipação da fase reprodutiva. Essas condições concorrem para uma baixa produtividade e menor qualidade desta hortaliça. Com o objetivo de avaliar o desempenho produtivo e qualitativo de cultivares de alface americana em função do espaçamento de plantio, foi desenvolvido um experimento no período de agosto a outubro de 2014, na Horta do Departamento de Ciências Vegetais na Universidade Federal Rural do Semi-Árido em Mossoró, RN. O delineamento experimental usado foi o de blocos casualizados com quatro repetições, em esquema fatorial 3 x 4. Os tratamentos consistiram da combinação de três cultivares de alface americana (Amélia, Angelina e Tainá) e quatro espaçamentos de plantio (15 x 15 cm, 20 x 20 cm, 25 x 25 cm e 30 x 30 cm). Foram avaliadas características de produção e qualidade: altura média de plantas (cm), diâmetro médio de plantas (cm), número de folhas por planta, massa fresca da parte aérea (g planta-1), massa seca da parte aérea (g planta-1), produtividade (t ha-1), sólidos solúveis (%), acidez titulável (%), relação sólidos solúveis/acidez titulável, pH e açúcares solúveis totais (%). As cultivares apresentaram produtividades semelhantes, com uma média de 9,58 t ha-1. A redução no espaçamento de plantio resultou em maior produtividade sem, no entanto, interferir na massa fresca das plantas. As cultivares demonstraram semelhança quanto à acidez titulável e a relação sólidos solúveis/acidez titulável, enquanto para sólidos solúveis, Amélia e Angelina mostraram-se superiores à Tainá. Os sólidos solúveis e a relação sólidos solúveis/acidez titulável aumentaram com o espaçamento de plantio
26

Produção de arroz vermelho manejado organicamente sob irrigação localizada e densidade de plantio / Red rice production under organic management, drip irrigation and planting densities

Lira, José Flaviano Barbosa de 27 August 2015 (has links)
Made available in DSpace on 2016-08-16T13:31:43Z (GMT). No. of bitstreams: 1 JoseFBL_DISSERT.pdf: 724427 bytes, checksum: 3f95af98a8e1bce47de6a150408e6016 (MD5) Previous issue date: 2015-08-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The study was conducted at the Federal Institute of Rio Grande do Norte, in Ipanguaçu-RN, to determine the technical feasibility of planting and behavior of red rice (Oryza sativa L.) yield components under drip irrigation, organic management and different planting densities. The treatments consisted of the number of plants per hole (1, 3, 5, 7 and 9) which were tested in a randomized block design with five replications. The variables analyzed were: number of tillers per hill, plant height, number of panicles per plot, average panicle mass, numbers of filled and of empty grains, percentage of empty grains, mass of one hundred grains and yield. Conclusions appoint the technical feasibility of the red rice crop and indicate the density of one plant per hill as the most appropriate for the site, the planting configuration employed, drip irrigation and organic management of red rice / O trabalho foi desenvolvido nas dependências do Instituto Federal do Rio Grande do Norte em Ipanguaçú-RN, para determinar a viabilidade técnica do plantio e o comportamento de componentes de produção de Arroz Vermelho (Oryza sativa L.) sob irrigação localizada, manejo orgânico e diferentes densidades de plantio. Os tratamentos constaram do número de plantas por cova (1, 3, 5, 7 e 9) que foram testados em delineamento de blocos ao acaso com cinco repetições. As variáveis estudadas foram: número de perfilhos por touceira, altura de plantas, número de panículas por parcela, massa média de panículas, números de grãos cheios e de grãos vazios, percentagem de grãos vazios, massa de cem grãos e produtividade. Concluiu-se pela viabilidade técnica da cultura do arroz vermelho e pela indicação da densidade de uma planta por cova como a mais adequada para o local, configuração de plantio utilizada, irrigação localizada e manejo orgânico do arroz vermelho
27

Desempenho de cultivares de cebola em função do espaçamento entre plantas / Performance of onion cultivars in function the spacing between plants

Santos, Jandeilson Pereira dos 17 February 2017 (has links)
Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2017-06-26T20:37:46Z No. of bitstreams: 1 JandeilsonPS_DISSERT.pdf: 2017152 bytes, checksum: b179723b01d0825959758fd95f3a9f43 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-06-27T14:25:50Z (GMT) No. of bitstreams: 1 JandeilsonPS_DISSERT.pdf: 2017152 bytes, checksum: b179723b01d0825959758fd95f3a9f43 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-06-27T14:25:57Z (GMT) No. of bitstreams: 1 JandeilsonPS_DISSERT.pdf: 2017152 bytes, checksum: b179723b01d0825959758fd95f3a9f43 (MD5) / Made available in DSpace on 2017-06-27T14:26:25Z (GMT). No. of bitstreams: 1 JandeilsonPS_DISSERT.pdf: 2017152 bytes, checksum: b179723b01d0825959758fd95f3a9f43 (MD5) Previous issue date: 2017-02-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In Brazil, The onion is traditionally cultivated by the transplant system of seedlings, However, the system of direct sowing comes been adopted by the producers of Minas Gerais, São Paulo and Goiás. In the Northeast region, in addition to Bahia, many producers uses this method of sowing, together with hybrid cultivars in dense planting and drip irrigation, However the responses regarding productivity and bulb quality are not always as expected. The objective of this work was to evaluate the performance of onion cultivars in function of the spacing between plants. The experimental design was in randomized complete block in a 3 x 4 factorial scheme, with four replications. The treatments consisted of three onion cultivars (Vale Ouro IPA 11, Serena and Rio das Antas) and four plant spacings (3, 6, 8 and 10 cm). The evaluated characteristics were: plant height, number of leaves, percentages of bulbs classes 1, 2, 3 and 4, total, commercial and non-commercial productivity of bulbs, average bulb mass, bulb mass weight, Bulb format, soluble solids, titratable acidity, soluble solids ratio / titratable acidity. The cultivars Rio das Antas and Serena obtained higher productive performance, being the most suitable for cultivated crops. The IPA 11 cultivar, regardless of the spacing between plants, provided higher pungency and soluble solids content, being the most suitable for industrial processing and preserves / No Brasil, a cebola é tradicionalmente cultivada pelo sistema de transplante de mudas, no entanto, o sistema de semeadura direta vem sendo adotado pelos produtores de Minas Gerais, São Paulo e Goiás. Na região Nordeste, além da Bahia, muitos produtores utilizam esse método de semeadura, juntamente com cultivares híbridas em plantio adensado e irrigação por gotejamento, porém, nem sempre as respostas com relação à produtividade e qualidade de bulbos são às esperadas. O objetivo deste trabalho foi avaliar o desempenho de cultivares de cebola em função do espaçamento entre plantas. O delineamento experimental utilizado foi em blocos casualizados completos em esquema fatorial 3 x 4, com quatro repetições. Os tratamentos foram constituídos da combinação de três cultivares de cebola (Vale Ouro IPA 11, Serena e Rio das Antas) e quatro espaçamentos entre plantas (3, 6, 8 e 10 cm). As características avaliadas foram: altura de plantas, número de folhas, porcentagens de bulbos de classes 1, 2, 3 e 4, produtividades total, comercial e não comercial de bulbos, massa média de bulbos, massa seca de bulbos, pungência, relação de formato de bulbos, sólidos solúveis, acidez titulável, relação sólidos solúveis/acidez titulável. As cultivares Rio das Antas e Serena obtiveram maior desempenho produtivo, sendo as mais indicadas para cultivos adensados. A cultivar IPA 11, independentemente do espaçamento entre plantas, proporcionou maior pungência e teor de sólidos solúveis, sendo a mais indicada para processamento industrial e conservas / 2017-06-26
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Capacidade competitiva de cultivares de feijão-caupi (Vigna unguiculata (L.) Walp) combinada com espaçamento na supressão de plantas daninhas.

Oliveira, Odiluza Maria Saldanha de 24 February 2014 (has links)
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No. of bitstreams: 1 Tese - Odiluza Maria Saldanha de Oliveira.pdf: 778336 bytes, checksum: d9880fba205424a41ded1fcbc88afd94 (MD5) Previous issue date: 2014-02-24 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / The weed interferencein in crop areas of cowpea reduces their yield of cowpea at 90%, varying in intensity that depends on factors related to weeds community Among the options for weed management, is the cultural method in which the use of cultivars with high competitive ability coupled with narrow row spacing provides conditions for the culture to be established effectively on the soil surface. However, in order not to compromise the yield of cowpea proper use of plant density, which depends on the intrinsic characteristics of the cultivar as size, growth habit, plant architecture and management system used is required. Analysis of the correlation coefficient is a complementary tool to assess the contribution of each factor in the productivity of cowpea under this stress situation. The objective of this experiment was to evaluate the competitiveness of cowpea cultivars at different spacings in upland soil in the state of Amazonas. The experimental design was a randomized complete block with three replications, arranged in sub-subplots. In the plots was used the row spacings of 0,50 m (recommended); 0,40 m and 0,30 m; in the subplots two system of control of weeds, and in sub-subplots cultivars of cowpea caupi BR8 Caldeirão, IPEAN V69, BRS Guariba e BR 17 Gurguéia. Were evaluated: leaf area, dry weight of leaves and of the aerial part, size of pods, number of pods per plant, number of pods, number of seeds per pod, harvest index, one hundred seed weight and yield, leaf area ratio, specific leaf area and leaf area index. Weed evaluation was carried at intervals of 7 days with the use of a square of 0.25 m2 that was carried out with in the useful area subplot for identification, counting and collecting weeds bounded by the square to verify the dry weight of shoots. The phytosociological parameters of frequencies, densities and abundances relative and absolute indices and importance value of species were calculated. It was used the path analysis to decompose the different correlations and their direct and indirect effects. The cv. BR8 Caldeirão had the highest values for measured characteristics followed in order of decreasing values for BRS Guariba, BR 17 Gurguéia IPEAN V69 viii respectively. The yield of cvs. showed a similar trend to the other variables analyzed. The spacing between rows of plants was not significant for productivity, but the cultivars differed from each other between different linear arrangements. The weeds highest IVI in row spacing of 0,5 e 0,4 m were Croton glandulosus and Mimosa pudica for 0,3 m. The most important species for the quantity cvs. were Paspalum multicaule for BR8 Caldeirão, Elephantopus mollis to BRS Guariba and Cleome affinis to IPEAN V69 and BR 17 Gurguéia. IPEAN V69 was the most susceptible to weed competition for dry matter production.The number of pods per plant and leaf area were the features most correlated with productivity. These features showed to be efficient for indirect selection to obtain genetic gains on the productivity of grains. Moreover, these features are also important on the indirect effects of the number of seeds per pod, plant height and dry weight of the aerial parts. / Plantas daninhas em área de cultivo de feijão-caupi causam interferência que pode reduzir a obtenção de grãos em até 90%, o que dependerá de fatores ligados à comunidade infestante. Dentre as opções de manejo das plantas daninhas, encontra-se o método cultural em que o uso de cultivares com elevada capacidade competitiva aliado à redução do espaçamento entrelinhas fornece condições para que a cultura se estabeleça eficazmente na superfície do solo. Entretanto, para não comprometer a produtividade da cultura de feijão-caupi é necessária a utilização adequada da densidade das plantas, o que depende das características intrínsecas da cultivar como porte, hábito de crescimento, arquitetura de planta e do sistema de manejo utilizado. Para quantificar a contribuição de cada fator na produtividade do feijão-caupi nesta situação de estresse competitivo é realizada complementarmente a análise de coeficiente de correlação. O objetivo deste experimento foi avaliar a capacidade competitiva de cultivares de feijão-caupi em diferentes espaçamentos em solo de terra firme no estado do Amazonas. O experimento foi delineado em parcelas sub-subdivididas em blocos casualizados com três repetições. Na parcela foram usados os espaçamentos de 0,50 m (recomendado); 0,40 m e 0,30 m; nas subparcelas os dois sistemas de manejo das plantas daninhas com e sem capina e nas sub-subparcelas as cultivares de feijão-caupi IPEAN V69, BR8 Caldeirão; BRS Guariba; BR 17 Gurguéia. Foram determinadas a área foliar, massa seca das folhas e da parte aérea, tamanho das vagens, número de vagens por planta, número total de vagens, número de sementes por vagem, índice de colheita, peso de cem sementes e produtividade, razão da área foliar, área foliar especifica e índice de área foliar. A avaliação da infestação de plantas daninhas foi realizada em intervalos de 7 dias com a utilização de um quadrado de 0,25 m2, lançado aleatoriamente na área útil da sub-subparcela não-capinada para identificação, contagem e coleta das plantas daninhas delimitadas pelo quadrado para verificar a massa seca da parte aérea. Foram calculados os parâmetros fitossociológicos das espécies. Estimou-se as vi correlações genotípicas entre pares de caracteres e seus efeitos diretos e indiretos considerando os componentes de produção. A cv. BR8 Caldeirão apresentou os maiores valores para as características avaliadas, seguida respectivamente em ordem decrescente de valores por BRS Guariba, BR 17 Gurguéia e IPEAN V69. A produtividade das cvs. seguiu tendência similar às demais variáveis analisadas. Os espaçamentos entre linhas não foram significativos para a produtividade, mas as cultivares diferiram entre si dentro de cada espaçamento. As plantas daninhas com maior IVI foram Croton glandulosus nos espaçamentos de 0,5 e 0,4 m, Mimosa pudica para 0,3m e Paspalum multicaule para BR8 Caldeirão, Elephantopus mollis para BRS Guariba e Cleome affinis para IPEAN V69 e BR 17 Gurguéia. A cultivar IPEAN V69 foi a mais susceptível aos problemas de competição com a flora infestante quanto à produção de matéria seca. O número de vagens.planta-1 e a área foliar foram os caracteres mais correlacionados com a produtividade e se mostram eficientes em praticar-se seleção indireta, com o intuito de obter ganhos genéticos sobre o rendimento de grãos. A cultivar BR8 Caldeirão foi a que demonstrou maior habilidade competitiva com base nos parâmetros avaliados.
29

Agronomical and physiological factors affecting growth, development and yield of sweet potato in Ethiopia

Belehu, Terefe 26 July 2004 (has links)
Morphological and anatomical studies demonstrated the root formation characteristics of sweet potato. The presence and importance of preformed root primordia is recorded for the first time. On the vines root primordia are present in sets of four to ten adjacent to the leaf bases. These roots originate from the procambium on both sides of the leaf gap. Macroscopically the root tips of preformed root primordia protruding through the cortex and epidermis of the stems are prominent. The preformed root primordia produce adventitious roots, with pentarch, hexarch or septarch steles. Storage roots will under normal circumstances only originate from undamaged root primordia on the nodes of cuttings, or on nodes of newly formed vines, or from wound roots originating from the cut ends of the stem or leaf cuttings. Lateral roots originating from damaged root primordia, or directly from the adventitious roots, exhibit tetrarch steles and develop into fibrous roots without the potential to develop into storage roots. This understanding of the origin, anatomy and morphology of sweet potato roots should improve production practices, which will contribute to improved crop establishment and increased yield. Differences in the contribution of individual subterranean nodes to storage root yield were studied. On average cuttings with three subterranean nodes produced 3.7 storage roots, with 33.2% on subterranean node 1, 30.0% on node 2 and 36.8% on node3. However, in terms of fresh mass of the storage roots node 1 contributed 45.4%, node 2 contributed 27.1% and node 3 contributed 27.4%. The effect of temperature (20, 24, 28 and 32oC constant), orientation of cuttings (vertical vs. horizontal) and size of cuttings (1 or 3 nodes) on the development of adventitious roots was observed in plant growth chambers. Twenty-one days after planting, the longest total root length of 4m per plant was recorded from the 24oC growth chamber. The effect of soil moisture content on early root development was investigated by wetting and equilibrating sandy soil to 100, 80, 60 and 40% of field capacity. Although the 80% of field capacity treatment resulted in the best root development, differences among treatments were small, demonstrating the capacity of cuttings to successfully establish under a range of soil moisture contents. Changes in dry mass of storage roots, stems, and leaves of three sweet potato cultivars (Awasa-83, Bareda and Falaha) were studied at Awasa and Melkassa. At the final sampling the early maturing cultivar Falaha had diverted a higher proportion of the total dry mass into storage roots at Melkassa because of the early initiation and growth of storage roots. The late maturing cultivar Awasa-83 had a smaller proportion of the total dry mass diverted into the storage roots at both locations because of late root initiation and growth. The high yielding cultivars Bareda at Melkassa, and Awasa-83 at Awasa, had higher crop growth rates and higher net assimilation rates than the other cultivars. The effects of cultivar (Kudadie, Bareda and Awasa-83), planting position (horizontal and vertical), type of planting material (terminal cuttings with and without leaves) and cutting length (20, 25 and 30 cm) on the number and yield of storage roots were quantified in field trials at Awasa and Melkassa. Cultivar Kudadie produced the highest storage root yield at both locations. Horizontal planting of cuttings resulted in the highest total storage root yield at both locations. Cutting length did not affect storage root number and yield. The effect of population density (50,000, 55,555, 75,000, and 100,000 cuttings per hectare) on the performance of the three Ethiopian sweet potato cultivars was studied at Awasa. The highest planting density consistently produced the best root yield, indicating the potential to increase yields with plant populations much higher than normally used. Early maturing cultivar Falaha produced more small and medium storage roots per plant, while the intermediate cultivar Bareda produced more large storage roots. Copyright 2003, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Belehu, T 2003, Agronomical and physiological factors affecting growth, development and yield of sweet potato in Ethiopia, PhD thesis, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-07262004-141704 / > / Thesis (PhD (Plant Production and Soil Science))--University of Pretoria, 2005. / Plant Production and Soil Science / unrestricted
30

Effect of agronomic management on growth and yield of selected leafy vegetables

Maseko, Innocent 06 1900 (has links)
African leafy vegetables have been shown and suggested to have potential to contribute to human diets and alleviate malnutrition; however, their levels of utilisation are currently low especially in South Africa. This is because there is limited access to these crops due to low availability in the market. Limited access is attributed, in part, to the lack of commercialisation as a result of limited agronomic information describing optimum management options for these leafy vegetables. Availability of such information would contribute to successful commercialisation of these crops. The primary objective of this study was to establish optimum agronomic management factors for Amaranthus cruentus, Corchorus olitorius, Vigna unguiculata and Brassica juncea for irrigated commercial production in South Africa. Seeds of Amaranthus cruentus, Corchorus olitorius were obtained from the Agricultural Research Council seed bank; Vigna unguiculata were obtained from Hydrotech and Brassica juncea seeds were obtained from Stark Ayres. The project consisted of three field studies whose overall objective was to evaluate growth and yield responses of the selected African leafy vegetables to agronomic factors under irrigated commercial production. These field studies comprised of two single factors; summer trials (planting density and nitrogen on three selected crops) and a combined winter trial (nitrogen, irrigation, plant density and planting date on a winter crop). Chapter three (3) investigated the effect of plant density on growth, physiology and yield responses of Amaranthus cruentus, Corchorus olitorius and Vigna unguiculata to three plant densities under drip irrigated commercial production. The plant density levels of 100 000, 66 666 and 50 000 plants/ha were used in the 2011/12 and 2012/13 summer seasons. Parameters measured included chlorophyll content index (CCI), chlorophyll fluorescence (CF), stomatal conductance (SC), leaf number, leaf area index (LAI) and biomass. Amaranthus cruentus and Corchorus olitorius showed better leaf quality at lower plant density of 50 000 plants ha-1 than at 66 666 plants ha-1 and 100 000 plants ha-1. These results are based on bigger leaves expressed as leaf area index (LAI), better colour expressed as chlorophyll (CCI) and higher biomass per plant observed in these crops at 50 000 plants ha-1 in comparison to 66 666 plants ha-1 and 100 000 plants ha-1. In Vigna unguiculata there were no responses observed in LAI and CCI. In Amaranthus cruentus, Corchorus olitorius and Vigna unguiculata fresh and dry mass yield of leaves were higher at 100 000 plants ha-1 compared to other treatments. In A. cruentus and C. olitorius, higher leaf quality parameters (CCI, plant height, leaf number, biomass per plant and LAI) indicated that these crops can perform better at lower densities of 50 000 than at 66 666 plants ha-1 and 100 000 plants ha-1 Therefore, using 50 000 plants ha- 1 is suitable for commercial production of A. cruentus and C. olitorius. In Vigna unguiculata, a plant density of 100 000 plants ha-1 produced the highest fresh and dry mass per unit area without compromising quality in terms of the leaf size (LAI) and colour (CCI). Therefore 100 000 plants ha-1 is a density recommended for commercial production in V. unguiculata.Chapter four (4) was conducted to investigate growth, physiology and yield responses of A. cruentus, C. olitorius and V unguiculata to nitrogen application under drip irrigated commercial production. Three nitrogen treatments levels were used viz. 0, 44 and 88 kg N ha- 1 in 2011/12 season and four nitrogen treatments levels viz. 0, 50, 100 and 125 kg N ha-1 were used in 2012/13 summer season. The nitrogen levels selected for each season were based on recommendations for Amaranthaceae species, Swiss chard (Beta vulgaris L.var cicla) derived from soil analysis of the trial (field) site. Parameters measured included chlorophyll content index (CCI), chlorophyll fluorescence (CF), stomatal conductance (SC), leaf number, leaf area index (LAI) and biomass. Results showed that application of nitrogen at 44 kg N ha- 1 in 2011/12 summer season and 100 kg N ha-1 in 2012/13 summer season improved LAI, CCI, biomass per plants and yield in A. cruentus. A similar trend was observed in C. olitorius except that 44 kg N ha-1 improved stem fresh yield. Further increase in nitrogen fertiliser above 44 kg N ha-1 during the 2011/12 season and above 100 kg N ha-1 in 2012/13 summer season reduced leaf quality and yield in both crops. In V. unguiculata, nitrogen application showed a slight increase in yield values from 0 to 44 kg N ha-1 followed by decrease at 88 kg N ha-1 in 2011/12 summer season; however, this increase in yield was not significant. During the 2012/13 summer season, yield in terms of fresh weight was significantly (P<.001) reduced by applying nitrogen at various levels. However, leaf dry matter content increased significantly (P<.001) with increase in nitrogen from 0 kg up to 100 kg N ha-1, then remained unchanged at 125 kg N ha-1. Therefore, the current study recommends that C. olitorius and A. cruentus could be commercialised at 44 kg N ha-1 and 100 kg N ha-1 which were lower nitrogen application rates than those recommended for Amaranthaceae species. In V. unguiculata, 50 kg N ha-1 improved leaf number; however, this did not translate to any fresh yield advantage, implying that the optimum rate for nitrogen application might be lower than 50 kg N ha-1. Therefore, nitrogen rates less than the ones used in the current study are recommended for V. unguiculata. Chapter five (5) was conducted in winter and it was necessitated by observations made primarily in the previous studies which focused on the effects of single factors such as plant density, planting date and nitrogen deficits. Therefore, there was a need to address interactions between irrigation, nitrogen, spacing and planting date. The objective of this study was to evaluate growth, physiology and yield responses of Brassica juncea to different agronomic and management factors in the 2012 and 2013 seasons. The treatments were as follows: two planting dates in main plot (1 June and 18 July, 2012); two irrigation frequency in sub main plot (once and three times a week); three nitrogen levels (0, 50, 100 kg N ha-1) and three plant densities (133 333, 80 000, 50 000 plants ha-1) as subplots. Parameters measured included chlorophyll content index (CCI), chlorophyll fluorescence (CF), stomatal conductance (SC), leaf number, leaf area index (LAI) and biomass. Results from this study showed a significant interaction effect on plant height, LAI, CCI and CF. Crops irrigated thrice or once a week with 50 kg N ha-1 combined with 50 000 plants ha-1 produced tall plants and bigger leaves (LAI) in the early planting date (1 June) compared to other combinations. Irrigating three times a week combined with nitrogen application at 100 or 50 kg N ha-1 improved CF for late planting date (18 July) in comparison to other combinations. Irrigating once a week combined with nitrogen application at 100 kg N ha-1 increased CCI. There was no significant interaction effect on yield. Application of nitrogen at 50 and 100 kg N ha-1 significantly (P>0.05) increased yield in early and late planting dates compared to the control (0 kg N ha-1), in 2012 and 2013 winter season. Irrigating three times a week led to a significant (P<0.05) increase in yield in the late planting date (18th July) and early planting date (1st June) in 2013 season. Higher plant density of 133 333 plants ha-1 resulted in significantly (P<0.05) higher yield in terms of fresh mass and leaf number in the late planting date 18 July in 2012 and 2013 seasons. However, leaf quality parameters such as leaf size and colour was compromised at 133 333 plants ha-1 relative to 50 000 plants ha-1. Therefore, farmers are recommended to plant early, apply 50 kg N ha-1, irrigate thrice a week and utilise a spacing of 50 000 plants ha-1. The current study indicates that growth and yield of traditional leaf vegetables can be optimised through improved agronomic practise. / Agriculture and Life Sciences / D. Litt. et. Phil. (Agriculture)

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