Made available in DSpace on 2014-06-11T19:30:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-09Bitstream added on 2014-06-13T19:40:07Z : No. of bitstreams: 1 aragao_ca_dr_botfca.pdf: 1161671 bytes, checksum: afd46a3743d52d4b2ec59f8c3237449e (MD5) / Visando avaliar o potencial produtivo de híbridos simples de milho super doce, bem como, a capacidade de combinação de vinte e cinco linhagens que lhes deram origem, através de um cruzamento dialélico parcial, foram avaliados cento e vinte híbridos, em São Manuel (SP) local 1, SAKATA/Sudameris (SP) local 2 e Arisco (GO) local 3, usando-se látice simples 11x11 com duas repetições por local. Foram tomados os dados de Produção total de espigas com palha corrigida para o estande; Produção comercial corrigida para o estande, Peso de cinco espigas comerciais com palha; Peso de cinco espigas comerciais sem palha; Produção espigas com. Sem palha, corrigida para estande e 76% de água, Comprimento de espigas; Diâmetro de espiga; Atura da planta e Altura de inserção espiga. As análises estatísticas e genéticas mostraram alta significância das interações de híbridos e capacidade geral e específica de combinação com os locais. De maneira geral observou-se maior produção para os caracteres avaliados no local 2 SAKATA/Sudameris. Comparando-se os híbridos testados com o híbrido comercial DO- 04, para todos os locais, observou-se que foi possível o desenvolvimento de híbridos simples (HS) superiores para a maioria dos caracteres avaliados. De maneira geral obteve-se uma boa combinação entre uma bom número de linhagens, sendo que para o caráter PC5Esp (76%), as melhores linhagens quanto à CGC, do grupo 1, foram 657; 750 e 656, do grupo 2, 636; 628 e 333. Foi possível indicar os seguintes híbridos específicos: (44)421x320 e (68)657x320, mostrando grande potencial para programas de melhoramento de milho doce. / One hundred and twenty simple hybrids of super sweet corn were evaluated at São Manuel, SP (site 1), SAKATA/Sudameris, SP (site 2) and at Arisco, GO (site 3), using simple lattice 11x11 with two replications aiming to estimate the producing potential of the hybrids, as well as the combination capacity of 25 inbreds that originated them, by a partial diallel crossing. The data assessed were total husked ear production corrected for stand; commercial production corrected for stand; weight of five commercial husked ears; weight of five commercial dehusked ears; dehusked ears production corrected for stand and 76% humidity; ear length; ear diameter; plant height and height of ear insertion. The statistical and genetic analysis showed high significance of hybrids interactions and general and specific combine ability with the sites. In general, an improved production was observed for the evaluated characters at site 2 SAKATA/Sudameris. Comparing the tested hybrids with the commercial hybrid DO-04, at all the sites superior simple hybrids were developed for every evaluated character. In general, there was a good combination between a great number of inbred. For the dehusked ears production corrected for stand and 76% humidity character, the best CGC inbreds of group1 were 657; 750 e 656, and of group 2 were, 636; 628 e 333. It was possible to indicate the specific hybrids: (44)421 x 320 and (68)657 x 320, which have great potential for sweet corn breeding programs.

Agricultural production is the main source of income and major employer in many countries in Africa, including Senegal. Commercial sweet corn (Zea mays L. ssp. saccharata) production in Senegal is increasing in response to global marketing opportunities and offers producers the ability to increase income and diversify the cropping base. Production of optimum sweet corn yield and quality depends on adequate nutrient supply, particularly, nitrogen (N). Current N recommendations are based on recommendations specific to corn for grain. This study aimed to identify tools to estimate sweet corn N status and determine the most appropriate fertilizer dosage for sweet corn. Non-destructive remote sensing tools and ion exchange resin membranes (IEMs) were used to evaluate the effect of fertilizer dose. No differences in ear yield or yield components, normalized difference vegetation index (NDVI) values, biomass, N uptake or leaf N concentration due to fertilizer dose were detected at Ndiol. However, significant relationships existed between NDVI values and yield, biomass, and N uptake at the V9 growth stage. Only yield was affected by fertilizer dose at Sangalkam, and no consistent relationships were found between chlorophyll meter readings and others measured parameters. Treatment differences due to fertilizer dose for available NH4+ at V9 (Ndiol), and NO3- at V5 (Sangalkam) were found, however further research is needed to fully evaluate the usefulness of IEMs to measure available soil N. Based on these studies, sweet corn fertilizer rates should likely be based on 75% of the dose applied to field corn, however more work is needed to confirm this finding. Pearl millet (Pennisetum glaucum (L) R. Br.) is the most widely grown staple crop in Senegal. Introduction of drought tolerant millet genotypes has helped mitigate the effect of increased water shortage in the region, but little is known about the nutritional composition of these genotypes. Our objective was to compare millet grain nutritional composition among and between putative drought tolerant and drought sensitive pearl millet lines under drought stress and well-watered conditions. One field experiment was conducted in 2014 at the National Center for Agronomic Research (CNRA) of Bambey, Senegal (16°30' and 16° 28' N; 15o44' and 15o42' W). The experiment utilized a split-plot design with four replications. Water regime was the main plot experimental factor while genotype, a total of 20 was the sub-plot. Pearl millet genotypes were divided into three contrasting groups based on drought tolerance for comparisons. Water stress did not affect 100-grain weight, test weight, protein, soluble protein, starch, sugars, amino acids or vitamin B2 content of grains among VPD-groups. Accumulation of these constituents of pearl millet grain appear to be genetically controlled and are probably not affected by late drought stress. However, differences were noted among genotypes as the sensitive VPD-group accumulated greater soluble protein, starch and soluble sugars (except sucrose) than the tolerant and medium VPD-groups. The tolerant VPD-group, however, accumulated greater protein and vitamin B2 content. Arginine, proline and serine content was greater in the sensitive VPD-group, while lysine, aspartic acid, and glutamic acid were greater in the tolerant VPD-group. Glycine, histidine, threonine, alanine, tyrosine, valine, methionine, leucine, isoleucine, and phenylalanine were relatively equal in tolerant and sensitive VPD-groups. Calcium and Na levels were affected by water stress in the sensitive VPD-group, but differently. Calcium content was greatest for the sensitive group under drought stress, while sodium was the lowest. Iron accumulation in sensitive VPD-group increased under water stress. Potassium decreased for all VPD-groups under stress, while across water regime, K levels in the drought-sensitive group were lower. Selection for drought appears to effect many of the nutritional constituents of pearl millet grain, however many of these differences appear to be directly related to parameters known to effect plant water relations. / Master of Science

A study was made to determine (1) the influence of plant spacing and nitrogen fertilizer on the yield, percentage of soluble solids, the toughness of the pericarp, and protein content of embryos and kernels of hybrid sweet corn, and (2) the influence of locally on the protein content of field corn varieties. The highest yield and weight of ears of sweet corn are obtained with plants spaced 6 inches apart. Of the three varieties, the medium-late maturing Seneca Chief is more desirable from the standpoint of higher yields and weight of ears. Northern Cross had the lowest number of total ears when grown 9 inches apart, and the other two varieties with 12 inches between plants in the row. Differences in earliness, yield, the weight of ears, and the number of ears per plot are found among the varieties studied. The number of shoots or tillers of Seneca Chief is higher than that of Northern Cross or Seneca Arrow; with increases in spacing the number of shoots per plant increases. The early maturing variety Northern Cross was less desirable in that the kernels at harvest contained a lower percentage of soluble solids, had the toughest pericarp; however, it contained a higher average percentage of total protein (15.31) than either Seneca Arrow (14.50) and Seneca Chief (13.56). Northern Cross also contained a higher average percentage of total protein in the embryos (17.00) than either Seneca Chief (16.44) and Seneca Arrow (14.87). The embryo protein, considered to be more digestible than the protein of the endosperm was not influenced by spacing treatments. Under the conditions of this experiment, there was no association between the amount of nitrogen fertilizer and the percentage of soluble solids, toughness of the pericarp, protein content, and yield of sweet corn. The supply of nitrogen seemed adequate since the corn crop followed a crop of soybeans. Considering the entire experiment, regardless of variety, spacing, and fertilizer levels, the increase in yield decreased the food value of sweet corn in terms of the protein content of the kernels but did not influence the protein content of the embryos this cannot be considered conclusive because of the limited experimental period and small number of hybrid studied. lt was found that the total protein content of kernel: of three field corn varieties grown in Central America varied more between locations than between varieties grown at the same location. The average protein content of the three field corn varieties ranged from 8.44% to 12.12%. Embryos of the field corn varieties contained a higher percentage of total protein than embryos of sweet corn. Thie fact suggests that field corn, which is low in quality from the standpoint of sweetness, contained a higher digestible protein content than sweet corn. / Master of Science

Typescript (photocopy). / Digitized by Kansas Correctional Industries

Orientador: Norberto da Silva / Resumo: Visando avaliar o potencial produtivo de híbridos simples de milho super doce, bem como, a capacidade de combinação de vinte e cinco linhagens que lhes deram origem, através de um cruzamento dialélico parcial, foram avaliados cento e vinte híbridos, em São Manuel (SP) local 1, SAKATA/Sudameris (SP) local 2 e Arisco (GO) local 3, usando-se látice simples 11x11 com duas repetições por local. Foram tomados os dados de Produção total de espigas com palha corrigida para o estande; Produção comercial corrigida para o estande, Peso de cinco espigas comerciais com palha; Peso de cinco espigas comerciais sem palha; Produção espigas com. Sem palha, corrigida para estande e 76% de água, Comprimento de espigas; Diâmetro de espiga; Atura da planta e Altura de inserção espiga. As análises estatísticas e genéticas mostraram alta significância das interações de híbridos e capacidade geral e específica de combinação com os locais. De maneira geral observou-se maior produção para os caracteres avaliados no local 2 SAKATA/Sudameris. Comparando-se os híbridos testados com o híbrido comercial DO- 04, para todos os locais, observou-se que foi possível o desenvolvimento de híbridos simples (HS) superiores para a maioria dos caracteres avaliados. De maneira geral obteve-se uma boa combinação entre uma bom número de linhagens, sendo que para o caráter PC5Esp (76%), as melhores linhagens quanto à CGC, do grupo 1, foram 657; 750 e 656, do grupo 2, 636; 628 e 333. Foi possível indicar os seguintes híbridos específicos: (44)421x320 e (68)657x320, mostrando grande potencial para programas de melhoramento de milho doce. / Abstract: One hundred and twenty simple hybrids of super sweet corn were evaluated at São Manuel, SP (site 1), SAKATA/Sudameris, SP (site 2) and at Arisco, GO (site 3), using simple lattice 11x11 with two replications aiming to estimate the producing potential of the hybrids, as well as the combination capacity of 25 inbreds that originated them, by a partial diallel crossing. The data assessed were total husked ear production corrected for stand; commercial production corrected for stand; weight of five commercial husked ears; weight of five commercial dehusked ears; dehusked ears production corrected for stand and 76% humidity; ear length; ear diameter; plant height and height of ear insertion. The statistical and genetic analysis showed high significance of hybrids interactions and general and specific combine ability with the sites. In general, an improved production was observed for the evaluated characters at site 2 SAKATA/Sudameris. Comparing the tested hybrids with the commercial hybrid DO-04, at all the sites superior simple hybrids were developed for every evaluated character. In general, there was a good combination between a great number of inbred. For the dehusked ears production corrected for stand and 76% humidity character, the best CGC inbreds of group1 were 657; 750 e 656, and of group 2 were, 636; 628 e 333. It was possible to indicate the specific hybrids: (44)421 x 320 and (68)657 x 320, which have great potential for sweet corn breeding programs. / Doutor

Orientador: Fernando Broetto / Banca: Roberto Lyra Villas Bôas / Banca: Marcelo Leonardo / Resumo: A deficiência hídrica é uma modalidade de estresse físico que afeta o desenvolvimento de diversas culturas agrícolas, causando impactos sociais e econômicos em regiões com baixa disponibilidade hídrica. Diversas pesquisas vêm trazendo como principal foco o estudo da deficiência hídrica na cultura do milho em épocas consideradas críticas a escassez hídrica. O objetivo do presente estudo foi avaliar o comportamento fisiológico e bioquímico de plantas de milho doce sob deficiência durante o estádio vegetativo. A hipótese principal é que as plantas de milho produzirão respostas fisiológicas interativas, no sentido de minorar o impacto dos tratamentos aplicados. O experimento foi conduzido em ambiente protegido em vasos 30L, irrigados via gotejamento, sob delineamento em blocos casualizados em esquema fatorial (3x3) sendo três lâminas de irrigação e três épocas de avaliação em parcelas subdivididas. Os tratamentos foram delimitados com objetivo de simular três níveis de deficiência hídrica (DH): T1 (Tratamento controle) - conduzidos dentro da faixa de umidade ótima para a cultura do milho até o final do ensaio (Tensão de 10 KPa); T2 (Deficiência hídrica moderada-DHM) - Plantas mantidas em tensão mínima de 50 KPa - e T3 (Deficiência hídrica severa-DHS) - Plantas mantidas sob tensão mínima de 70 KPa. As avaliações foram divididas em três épocas durante a imposição do estresse, visando monitorar alterações fisiológicas e bioquímicas das plantas, aos 45, 52 e 59 DAE. Cada tratamento f... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Water deficiency (WD) is a form of physical stress that affects the development of several agricultural crops, causing social and economic impacts in regions with low water availability. Several researches have been focusing on the study of water deficiency in maize crop in phenological stages critical to water scarcity. The aim of the present study was to evaluate the physiological and biochemical responses of sweet corn plants growing under water deficiency during the vegetative stage. The main hypothesis is that corn plants will produce interactive physiological responses, in order to reduce the impact of applied treatments. The experiment was conducted in protected environment in 30 L pots, irrigated via drip irrigation, under a randomized block design in a factorial scheme (3 x 3), three irrigation levels and three evaluation periods in subdivided plots. The treatments were delimited with the objective of simulating three levels of water deficiency: T1- Control (10 KPa) - conducted within the optimum humidity range for the maize crop until the end of the experiment; T2- Moderate water deficiency (50 KPa) and T3- Severe water deficiency (70 KPa). The evaluations were divided in three seasons during the imposition of stress treatments, aiming to monitor the physiological and biochemical changes of the plants at 45, 52 and 59 DAE (days after seed emergence). Each treatment was composed of 4 replicates and the soil moisture was monitored by tensiometry, maintaining the vessels in field capacity until the beginning of the treatments. When the plants entered the V7 stage, the proposed treatments with water deficiency were started. At this stage, the first collection (E1) was performed to analyze different parameters, which consisted of the initial point of evaluations. Under moderate and severe WD there were alterations of the main physiological and biochemical parameters. The growth and biomass ... / Mestre

The effect of serial (multiple-year) organic matter (OM) amendment on soil properties has been described in some cropping systems, although less is known about the effect of serially amended field soils on soil-borne plant diseases. The objectives of this study were to describe the effects of the third and fourth years of annual, serial amendment with dairy manure solids on 1) soil physical and biological properties and 2) severity of sweet corn root rot. Plots were amended with five rates of separated dairy manure solids annually for three years. In the fourth year, plots were split and only half of each plot was re-amended. Soil physical properties [bulk density, free and occluded particulate organic matter (POM), soil water retention, total porosity, gravimetric moisture content] and biological properties [microbial activity (as hydrolysis of fluorescein diacetate; FDA) and microbial biomass-C] were assessed each year in all treatments. Root rot severity was assessed in situ and in the greenhouse with multiple sweet corn (Zea mays L. cv Golden Jubilee) bioassays conducted in the amended field soils. Necrosis of the radicle and nodal roots was assessed when plants reached the 6- leaf stage. Amendment rate was positively associated with increases in soil properties that serve as indicators of soil quality, such as POM content, total porosity, microbial biomass, and FDA activity. In the third year after amendment, weak root rot suppression was observed in-field and was associated with FDA activity. By the fourth year of serial amendment this trend was no longer evident, however evidence from the high-rate treatment that was not re-amended (3HNRA) pointed to an emerging suppressive mechanism that persisted up to 13 months after the third amendment. Factors that may be interacting over time to generate observed disease suppression in these serially amended soils include: short-term post-amendment microbiostasis, soil moisture retention, inoculum potential, and a novel suppressive mechanism. / Graduation date: 2006

Thesis (Ph. D.)--Oregon State University, 2007. / Printout. Includes bibliographical references. Also available on the World Wide Web.

Made available in DSpace on 2014-06-11T19:28:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-09Bitstream added on 2014-06-13T19:37:06Z : No. of bitstreams: 1 ferreira_ac_me_jabo.pdf: 206579 bytes, checksum: ae1661430b2626c1ec623bac6a3fbb05 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / As sementes de milho-doce apresentam a espessura reduzida do pericarpo e maior quantidade de açúcares no endosperma e estas características tornam-nas mais suscetíveis aos danos mecânicos, à entrada e proliferação de patógenos e à deterioração, quando comparadas às de milho comum. Assim, as sementes de milho-doce apresentam menor longevidade no armazenamento e baixo desempenho em campo. O condicionamento fisiológico de sementes e o uso de fitorreguladores podem ser utilizados como técnicas para melhorar o desempenho de sementes. Este trabalho teve como objetivo avaliar os efeitos do condicionamento fisiológico, de fitorreguladores e do armazenamento no desempenho de sementes de milho-doce. Os seguintes tratamentos foram aplicados às sementes: tratamento 1 – sem condicionamento fisiológico; tratamento 2 – com condicionamento fisiológico; tratamento 3 – com condicionamento fisiológico + auxina (50 ppm); tratamento 4 – com condicionamento fisiológico + ácido giberélico (50 ppm) e tratamento 5 – com condicionamento fisiológico + auxina (50 ppm) + ácido giberélico (50 ppm). As sementes foram armazenadas em câmara fria com temperatura de 10 ºC ±1 ºC e umidade relativa do ar de 50% ±5% durante quatro meses. Imediatamente após o condicionamento fisiológico e após quatro meses, foram utilizados os testes de teor de água, teste de germinação, teste de envelhecimento acelerado, teste de frio com solo, teste de condutividade elétrica e teste de emergência de plântulas para avaliar o ensaio. O condicionamento fisiológico com e sem fitorreguladores não teve efeito sobre a germinação e o vigor de sementes de milho-doce, permitindo concluir que estas técnicas não tiveram efeitos positivos na qualidade das sementes de milho-doce nas condições do ensaio / The seeds of sweet corn have reduced the thickness of the pericarp and higher amount of sugars in the endosperm and these characteristics make them more susceptible to mechanical damage at the entrance and proliferation of pathogens and the deterioration when compared to normal corn. Thus the seeds of sweet corn in storage have reduced longevity and poor performance on the field. Priming and the growth regulators can be used as techniques to improve the performance of seeds. This study aimed to evaluate the effects of priming, growth regulators and storage on sweet corn performance. The following treatments were applied to seeds: treatment 1 - no priming; treatment 2 - priming; treatment 3 - priming + auxin (50 ppm); treatment 4 - priming + gibberellic acid (50 ppm) and treatment 5 - priming + auxin (50 ppm) + gibberellic acid (50 ppm). The seeds were stored in cold chamber with temperature of 10 ºC ± 1 ºC and relative humidity of 50% ± 5% for four months. Immediately after the priming and after four months, were used the water content test, germination test, accelerated aging, cold test with soil, electrical conductivity test and seedling emergency test to evaluate the assay. The priming with and without growth regulators had no effect on germination and seed vigor of sweet corn, the report concludes that these techniques did not have positive effects on quality of sweet corn seeds in the assay conditions

Orientador: Roberval Daiton Vieira / Banca: Ana Dionisia da Luz Coelho Novembre / Banca: Claudio Cavariani / Resumo: As sementes de milho-doce apresentam a espessura reduzida do pericarpo e maior quantidade de açúcares no endosperma e estas características tornam-nas mais suscetíveis aos danos mecânicos, à entrada e proliferação de patógenos e à deterioração, quando comparadas às de milho comum. Assim, as sementes de milho-doce apresentam menor longevidade no armazenamento e baixo desempenho em campo. O condicionamento fisiológico de sementes e o uso de fitorreguladores podem ser utilizados como técnicas para melhorar o desempenho de sementes. Este trabalho teve como objetivo avaliar os efeitos do condicionamento fisiológico, de fitorreguladores e do armazenamento no desempenho de sementes de milho-doce. Os seguintes tratamentos foram aplicados às sementes: tratamento 1 - sem condicionamento fisiológico; tratamento 2 - com condicionamento fisiológico; tratamento 3 - com condicionamento fisiológico + auxina (50 ppm); tratamento 4 - com condicionamento fisiológico + ácido giberélico (50 ppm) e tratamento 5 - com condicionamento fisiológico + auxina (50 ppm) + ácido giberélico (50 ppm). As sementes foram armazenadas em câmara fria com temperatura de 10 ºC ±1 ºC e umidade relativa do ar de 50% ±5% durante quatro meses. Imediatamente após o condicionamento fisiológico e após quatro meses, foram utilizados os testes de teor de água, teste de germinação, teste de envelhecimento acelerado, teste de frio com solo, teste de condutividade elétrica e teste de emergência de plântulas para avaliar o ensaio. O condicionamento fisiológico com e sem fitorreguladores não teve efeito sobre a germinação e o vigor de sementes de milho-doce, permitindo concluir que estas técnicas não tiveram efeitos positivos na qualidade das sementes de milho-doce nas condições do ensaio / Abstract: The seeds of sweet corn have reduced the thickness of the pericarp and higher amount of sugars in the endosperm and these characteristics make them more susceptible to mechanical damage at the entrance and proliferation of pathogens and the deterioration when compared to normal corn. Thus the seeds of sweet corn in storage have reduced longevity and poor performance on the field. Priming and the growth regulators can be used as techniques to improve the performance of seeds. This study aimed to evaluate the effects of priming, growth regulators and storage on sweet corn performance. The following treatments were applied to seeds: treatment 1 - no priming; treatment 2 - priming; treatment 3 - priming + auxin (50 ppm); treatment 4 - priming + gibberellic acid (50 ppm) and treatment 5 - priming + auxin (50 ppm) + gibberellic acid (50 ppm). The seeds were stored in cold chamber with temperature of 10 ºC ± 1 ºC and relative humidity of 50% ± 5% for four months. Immediately after the priming and after four months, were used the water content test, germination test, accelerated aging, cold test with soil, electrical conductivity test and seedling emergency test to evaluate the assay. The priming with and without growth regulators had no effect on germination and seed vigor of sweet corn, the report concludes that these techniques did not have positive effects on quality of sweet corn seeds in the assay conditions / Mestre