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‣ Use of chlrophyll fluorescence sorting to improve soybean seed quality; Utilização de fluorescência de clorofila na separação de sementes esverdeadas de soja

CICERO, Silvio Moure; SCHOOR, Rob Van Der; JALINK, Henk
Fonte: Associação Brasileira de Tecnologia de Sementes Publicador: Associação Brasileira de Tecnologia de Sementes
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
46.872407%
The occurrence of green seeded soybeans [Glycine max (L.) Merrill] is a problem closely related to unfavorable climatic conditions, mainly drought, that occurs during the final stages of seed maturation. This problem causes serious losses to soybean seed quality in Brazil. In these seeds, chlorophyll is not properly degraded during maturation, drastically reducing seed quality. Using the chlorophyll fluorescence technique, it is possible to remove green seeds from the seed lot, improving seed quality in several species in which the occurrence of green seeds is also a problem. The objective of this research was to study the use of the chlorophyll fluorescence technique in sorting green seeds from soybean seed samples and its effects on quality. Five seed samples of soybean, cultivar TMG 113 RR, with 0%, 5%, 10%, 15%, and 20% of green seeds were used in this study. Seeds from each sample were sorted into two fractions based on the chlorophyll fluorescence signals and then compared to the control (non-sorted seeds). The sorting process showed great differences between the low and high chlorophyll fluorescence fractions. It was concluded that: green seeds of soybeans present high chlorophyll fluorescence and that this characteristic affects the quality of the seeds; it is possible to improve the quality of soybean seed by removing green seeds using the chlorophyll fluorescence sorting technique.; A ocorrência de sementes esverdeadas de soja [Glycine max (L.) Merrill] é um problema estreitamente relacionado a condições climáticas desfavoráveis...

‣ Efeito de Colletotrichum dematium var. truncata e Cercospora kikuchii na germinação de sementes de soja

Galli, Juliana Altafin; Panizzi, Rita de Cássia; Fessel, Simone Aparecida; Simoni, Fabiana de; Ito, Margarida Fumiko
Fonte: Associação Brasileira de Tecnologia de Sementes (ABRATES) Publicador: Associação Brasileira de Tecnologia de Sementes (ABRATES)
Tipo: Artigo de Revista Científica Formato: 182-187
Português
Relevância na Pesquisa
46.85609%
A antracnose, causada por Colletotrichum dematium var. truncata, é a principal doença da soja que afeta a fase inicial de formação das vagens, podendo causar a morte das plântulas. Cercospora kikuchii é o fungo causador da doença mancha púrpura nas sementes de soja, responsável por severas reduções no rendimento e na qualidade das sementes. O objetivo deste trabalho foi determinar o tempo mais apropriado para infecção das sementes de soja por C. dematium var. truncata e C. kikuchii, para posterior avaliação dos danos causados pelo fungo na germinação. Tais fungos foram cultivados em meio BDA. As sementes de soja cultivar MSOY 6101 foram colocadas sobre meio contendo o patógeno C. dematium var. truncata por 0 (testemunha), 4, 16, 24, 32 e 40h. As sementes da cv. CD 208 foram inoculadas com C. kikuchii pelos mesmos períodos citados, com adição de 48 e 56h. Após os respectivos tempos de contato, as sementes foram submetidas ao teste de sanidade (papel de filtro), com duas variações, sem e com assepsia superficial (hipoclorito de sódio 1% por três minutos). Determinado o tempo mais adequado de infecção, outras sementes foram infectadas pelo patógeno e, posteriormente, foram realizados testes de germinação em papel e areia com uma mistura de sementes sadias (colocadas sobre o meio BDA) e sementes inoculadas...

‣ Uso da restrição hídrica na inoculação de fungos em sementes de algodoeiro (Gossypium hirsutum)

Machado,José da Cruz; Oliveira,João Almir de; Vieira,Maria das Graças G.C.; Alves,Marcelo de C.
Fonte: Associação Brasileira de Tecnologia de Sementes Publicador: Associação Brasileira de Tecnologia de Sementes
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2004 Português
Relevância na Pesquisa
46.85609%
A disponibilidade de sementes com diferentes níveis de infecção por fungos ou outros patógenos transmissíveis por esta via é extremamente importante para diversos estudos em patologia de sementes. A presente pesquisa teve como objetivo avaliar o uso da restrição hídrica na inoculação de sementes de algodoeiro com vistas à obtenção de sementes infectadas por Colletotrichum gossypii, C. gossypii var. cephalosporioides, Botryodiplodia theobromae e Fusarium oxysporum f. sp. vasinfectum. A premissa foi baseada no fato de que infecção de sementes pode ser assegurada e controlada pela manutenção das sementes em contato com a colônia fúngica em desenvolvimento em meio agarizado contendo manitol em potencial osmótico que impeça, temporariamente, a germinação por períodos de incubação mais prolongados. Neste trabalho manitol foi testado nos potenciais hídricos de 0, -0,4, -0,6, -0,8 e -1,0 MPa. As sementes foram incubadas em câmara de crescimento vegetal a 25ºC, com fotoperíodo de 12 horas, permanecendo nestas condições por tempos variáveis, de acordo com o potencial hídrico utilizado. As sementes foram retiradas do meio e secadas sobre papel de filtro, em condições de laboratório e submetidas aos testes de germinação...

‣ Efeito de Colletotrichum dematium var. truncata e Cercospora kikuchii na germinação de sementes de soja

Galli,Juliana Altafin; Panizzi,Rita de Cássia; Fessel,Simone Aparecida; Simoni,Fabiana de; Ito,Margarida Fumiko
Fonte: Associação Brasileira de Tecnologia de Sementes Publicador: Associação Brasileira de Tecnologia de Sementes
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2005 Português
Relevância na Pesquisa
46.85609%
A antracnose, causada por Colletotrichum dematium var. truncata, é a principal doença da soja que afeta a fase inicial de formação das vagens, podendo causar a morte das plântulas. Cercospora kikuchii é o fungo causador da doença mancha púrpura nas sementes de soja, responsável por severas reduções no rendimento e na qualidade das sementes. O objetivo deste trabalho foi determinar o tempo mais apropriado para infecção das sementes de soja por C. dematium var. truncata e C. kikuchii, para posterior avaliação dos danos causados pelo fungo na germinação. Tais fungos foram cultivados em meio BDA. As sementes de soja cultivar MSOY 6101 foram colocadas sobre meio contendo o patógeno C. dematium var. truncata por 0 (testemunha), 4, 16, 24, 32 e 40h. As sementes da cv. CD 208 foram inoculadas com C. kikuchii pelos mesmos períodos citados, com adição de 48 e 56h. Após os respectivos tempos de contato, as sementes foram submetidas ao teste de sanidade (papel de filtro), com duas variações, sem e com assepsia superficial (hipoclorito de sódio 1% por três minutos). Determinado o tempo mais adequado de infecção, outras sementes foram infectadas pelo patógeno e, posteriormente, foram realizados testes de germinação em papel e areia com uma mistura de sementes sadias (colocadas sobre o meio BDA) e sementes inoculadas...

‣ Qualidade física e fisiológica de sementes de Eremanthus erythropappus (DC.) Mac. Leish

Tonetti,Olivia Alvina Oliveira; Davide,Antonio Claudio; Silva,Edvaldo Aparecido Amaral da
Fonte: Associação Brasileira de Tecnologia de Sementes Publicador: Associação Brasileira de Tecnologia de Sementes
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2006 Português
Relevância na Pesquisa
46.879287%
Este trabalho teve como objetivo identificar e sugerir métodos para avaliação da qualidade física e fisiológica de sementes de candeia (Eremanthus erythropappus). As sementes utilizadas foram colhidas nos anos de 2001 e 2002, respectivamente nos municípios de Carrancas e Lavras, no estado de Minas Gerais. As sementes foram secas, limpas e guardadas em sacos semipermeáveis, em câmara fria a 5ºC e 60% de umidade relativa até o início dos experimentos. Para facilitar a identificação de sementes vazias foi desenvolvido protocolo com a utilização de raios-x, combinando potência de radiação (Kv) e tempo de exposição das sementes à radiação (segundos). Para a eliminação das sementes vazias foi realizado experimento utilizando soprador de sementes, tipo South Dakota, combinando as aberturas do aparelho e tempo. Para os testes de germinação, as sementes foram passadas pelo soprador, lavadas em hipoclorito de sódio e colocadas para germinar sobre papel, em gerbox. O primeiro experimento avaliou temperaturas de germinação e foi realizado em mesa termogradiente, o segundo experimento testou sensibilidade à luz e alternância de temperatura e foi conduzida em germinadores tipo Mangelsdorfii. Foram determinadas curvas de embebição...

‣ Ocorr??ncia de sementes com casca aberta na produ????o de sementes de arroz h??brido irrigado no estado de Roraima; Open husk seeds ocurrence in hybrid rice seed production in lowland areas in the state of Roraima

SOARES, Maur??cio Jur??
Fonte: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR Publicador: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
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The production of hybrid rice seeds in the state of Roraima takes place in two crops per year. About 70% of which is held between the months October to March the following year, called the summer crop, and the remaining 30% occur in the winter season (April to September of that year). Yields of winter of 2009, 2010 and 2011 were limited by the occurrence of shelled seeds in open fields to produce the Hybrid rice seeds, cultivar Avaxi CL. The objective of this study was to survey the occurrence of seeds in shell open in the three growing seasons of winter and their problems in losses in seed processing and seed quality. Data were presented on the loads of trucks coming from the seed production fields. The procedures for obtaining samples and the sampling intensity were performed in accordance with Rules for Seed Analysis. The data of the percentage of open shelled seeds was systematized by the truck loads of seeds, depending on the time of seed harvest and according to the different areas used for seed production. Data were also taken for germination of seed lots produced and thousand seed weight. Yields were low harvests in 2009, 2010 and 2011, for this season, in relation to productivity typically observed in summer crops. The occurrence of seeds with open shells ranged from 15.1% to 29.9%...

‣ Aplica????o de c??lcio/magn??sio e sil??cio nas sementes de soja; Application of clacium and magnesium + silicon in soybean seeds

RUFINO, Cassyo de Ara??jo
Fonte: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR Publicador: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
46.879287%
The aim of this study was to evaluate the effect of coating of soybean seeds with calcium / magnesium and silicon verified through the physiological quality, yield components and plant growth. We used two micronutrients, calcium and silicon (limestone and kaolin), both at a dose of 50 g/kg-1 seed. The treatments were a combination of coating seeds and cultivars: RR Power BMX - T1 (Ca / Mg Si), T2 (Ca / Mg), T3 (Si) and T4 (No micronutrients), CD 226 RR - T1 (Ca / Mg Si), T2 (Ca / Mg), T3 (Si) and T4 (No micronutrients). For the growth analysis were analyzed the following variables: leaf area, plant height, shoot dry matter, crop growth rate (CBT), relative growth rate (RGR) and net assimilation rate (NAR). For the physiology and yield components, were performed the following tests: germination, first count germination, accelerated aging, weight of thousand seeds, seed mass per plant, plant height, stem diameter, number of pods and seeds per plant, harvest index, biological yield, total seedling length, shoot and root. For all variables analyzed were used an experimental design of randomized blocks in factorial 2x4 (two cultivars and four combinations of seed coating with Ca and Mg + Si). The coating of soybean seeds can be an alternative to seed treatment because it promotes greater leaf area and dry matter production. The plants originated from the seed coating with calcium and magnesium + silicon produced good results for the growth rate...

‣ Gradiente de umidade na matura????o de sementes de milho doce e sua qualidade fisiol??gica; Moisture gradient in the maturation of the sweet corn seed and it s physiological quality

PERRETTO, ??lcio Luiz
Fonte: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR Publicador: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR
Tipo: Tese de Doutorado Formato: application/pdf
Português
Relevância na Pesquisa
46.85609%
The aim of this study was to identify the ideal sweet corn seed harvest moment by different determinations like moisture gradient in each harvest, moisture content, seeds dry matter, Hot Unity and physiological quality. Four genotypes of sweet corn, carrier of gene shrunken 2 (sh2) and nominated super sweet was used in this study. Ears from plants in the same development stage were collected. Seed harvest for the first genotype began 39 days after the flowering at intervals of two days until to complete eight harvest periods. Morphological determinations evaluated were moisture gradient between the seeds in each harvest, moisture content, seeds dry matter and Hot Unity. Seeds physiological quality was evaluated by germination test, first count of germination, soil emergence and cold test, without soil. Based on the results, the conclusions are: 1) the ideal moment to harvest sweet corn was with seed moisture content between 40 and 60% depending on genotype; 2) the ideal period to harvest the seed of sweet corn varies among genotypes; 3) the Hot Unity between 2007 to 2160??C relates to the best times to harvest the genotypes of sweet corn; 4) the moisture gradient of the seeds in a ear of sweet corn can reach more than 40 percentage points; 5) the seed moisture loss on the ear reaches around 1.5 percentage points per day after 40 days of flowering.; O objetivo deste trabalho foi identificar o momento ideal de colheita de sementes de milho doce...

‣ Produ????o e beneficiamento de sementes de trigo na empresa Sementes Estrela Erechim,RS; Case of study: wheat seed production and conditioning at "sementes estrela" seed company in Erechim, RS, Brazil

WEBBER, Tiago Antonio
Fonte: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR Publicador: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
46.89111%
The objective of the present study was to analyze the efficiency of wheat seed production and conditioning at the Sementes Estrela seed company located in the Erechim county, RS state, Brazil, during 2006/07, 2007/08 and 2008/09 crop seasons. Data of area and volume registered for seed production, receiving, conditioning and aprovation, germination and comercialization of wheat seed lots. Cultivars studied were: Abalone; Safira; Alcover; Pampeano; Onix; Quartzo; Marfim; BRS Timbauva; BRS Guamirim; BRS 208; Fundacep Nova Era; Fundacep 52; Fundacep Cristalino e Fundacep Raizes. The results shown that wheat seed production at Sementes Estrela represents 3.87% of the state of Rio Grande do Sul production. There is a difference between registered volume and volume received of wheat seeds of about 15%. The efficiency of wheat seed conditioning is increasing each crop season, being the seed loss of about 22%. In the last two crop seasons the wheat seed conditioned and approved is 100%. Germination of approved seed lots is above the standard stablished by the seed company in all crop seasons. Commercialization of wheat seeds at Sementes Estrela company is above 90% of seed lots conditioned but shows a tendency of reducing in the last crop season.; O presente estudo teve como objetivo analisar a efici??ncia da produ????o e do beneficiamento de semente de trigo na empresa Sementes Estrela localizada em Erechim...

‣ Sil??cio oriundo da cinza de casca de arroz carbonizada como promotor do rendimento e da qualidade fisiol??gica de sementes de soja; Silicon derived ash rice hulls as a promoter yield and seed quality of soybean

OLIVEIRA, Sandro de
Fonte: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR Publicador: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
46.85609%
Soybean is an important crop for Brazilian agriculture. The use of quality seeds, as well as appropriate plant nutrition and the adoption of modern techniques of cultivation are fundamental to the success of the crop. The use of silicon is a clean technology to environmentally and in addition may offer several benefits to plants. The aims of this study were to evaluate the effect of application of silicon from carbonized rice husk through the seed treatment and from soil in two soybean cultivars, and evaluate physiological quality of treated seeds, morphologic characteristics, yield components, yield and physiological quality of the seed produced. Four experiments were performed in randomized complete block design, using carbonized rice husk as a source of silicon. The experiments differ as the application form of carbonized rice husk and five doses of silicon were applied using seed coating (0, 30, 60, 90, and 120 g 100 kg seed-1) and throught soil were used the following doses (0, 1, 2, 3, and 4 tons ha-1). The soybean cultivars used in this study were (BMX Turbo RR and NA 5909 RR). Physiological quality of treated seeds and seed produced were evaluated by germination test and vigor tests. Morphological characteristics and yield components were also analyzed. The results showed that the application rates of silicon in the soil increases productivity...

‣ Plantabilidade de sementes de soja classificadas por largura; Plantability soybean seed classified by size

RODRIGUES, Claiton
Fonte: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR Publicador: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR
Tipo: Tese de Doutorado Formato: application/pdf
Português
Relevância na Pesquisa
46.85609%
The change in the profile of soybean varieties which favor the reduction of population is accompanied by the necessity of enhancement in the process for classifying seeds by size, standardizing the distribution in the sowing row. The present study aimed to characterize the classification of soybean seeds by size with the purpose of precision sowing. The first experiment conceptualized sorted lots at intervals of 0.5mm, 1.00mm, and unrated by size. To that end, the retention in the dominant sieve and number of diameters found in each of the intervals evaluated were used as parameters. In the second experiment combinations of intervals of classification by size of 0.5mm, 1.00mm, and unrated by size with different seed base diameters in a soybean cultivar. 5.0mm, 5.5mm, 6.0mm, and 6.5mm diameters were used. We evaluated the percentage of sowing at normal spacing, double spacing, spacing at failure, spacing at double failure, average spacing, number of seeds per linear meter, and population per hectare. A speed of 6.5km/hr was set for evaluation and desired sowing density of 14 seeds per linear meter. In the Experiment 3 the same parameters of the Experiment 2 were evaluated, but in four different soybean cultivars. The equipment used in the Experiments 2 and 3 to evaluate the plantability was Corn Counter from Syngenta. In the Experiment 4 the evaluation involved 182 samples of soybean seed lots collected in the warehouses of seeds buying companies. A quality assessment of classification by seed company size from Brazil...

‣ M??todo de estufa para determina????o do grau de umidade de sementes de arroz e soja; The oven drying method for determination of the moisture content of rice and soybean seeds

LOPES, Madelon Schimmelpfennig
Fonte: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR Publicador: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR
Tipo: Tese de Doutorado Formato: application/pdf
Português
Relevância na Pesquisa
46.872407%
The aim of this work was to a) compare the standard official methodology in Brazil for the determination of the moisture content of rice and soybean seeds (i.e. oven dried at 105??C for 24 hours) to the ISTA standard method (103??C for 17 hours), and b) test the possibility to determine whether the moisture content (MC) of rice and soybean seeds can be accurately estimated drying for a period shorter than 24h. Previously, a study was performed to establish the influence of the sample position within the oven, aimed to reduce the variation of the results on MC among different seed samples. The rice and soybean seeds tested in the experiment showed MC as determined by oven drying at 105??C/24h of 9.0%; 17.6% and 7.5%; 16.8%, respectively. The MC of whole rice and soybean seeds was estimated through oven drying at temperatures of 70, 103, 105 e 130??C for periods of 1, 3, 5, 7, 17, 24, 48, 72 and 96 hours for each level of temperature. Following ISTA standards, ground seeds were employed to determine their MC through the standard procedure (oven dried at 103??C/17h), whereas for the alternative procedure rice seeds were oven dried at 130??C for two hours. It was concluded that drying at 105??C/24h either underestimate the MC of rice and soybean seeds...

‣ Potencial fisiol??gico e teor de macro e micronutrientes em sementes de feij??o utilizando material crioulo e melhorado por sele????o participativa; Potential physiological and content of macro and micronutrients of bean seeds using landraces and improved cultivars by participatory selection

Alves, Carla Xavier
Fonte: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR Publicador: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
46.879287%
The bean is consumed by a large part of the population and is an important source of nutrients, which may have their levels increased with the use of genotypes that have naturally high levels of these nutrients. In Brazil, the beans is grown mainly by small farmers, who often use seeds from previous years, selected by the farmers themselves for years, characterizing them as native seeds. These seeds are great source of genetic variability, with high potential for direct use by farmers and use in breeding programs. Knowledge of characteristics that influence the quality of seeds is crucial for the selection of the best genotypes to be used. A characteristics mentioned is the concentration of nutrients in the seeds. The study aimed to evaluate the physiological quality and nutrient content in seeds of landraces and improved cultivars for participatory selection, and the influence of the content of these nutrients in seed vigor. The seeds used were produced in S??o Luiz Gonzaga and Sobradinho, RS, from cultivar evaluation trials of 2011/2012 season. Were evaluated seeds: germination, accelerated aging, cold, electrical conductivity and root length and shoot length in seedlings. We also evaluated the levels of phosphorus, calcium, potassium...

‣ Comportamento de plantas de arroz h??brido em fun????o da qualidade fisiol??gica das sementes; Hybrid rice plants behavior regarding the seeds physiological quality

MIELEZRSKI, Fabio
Fonte: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR Publicador: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
46.86472%
The work had the objective of evaluating the behavior of populations of hybrid rice plants which were cultivated isolated, and the individual behavior and plants originated from seeds of high and low vigor of hybrid rice, inside of populations that were constituted of different combinations of seed line distributions. The experiment was conducted in the didactic experimental area of the agronomy school. It was used seeds of hybrid rice of the cultivar Avaxi, which belongs to the Ricetec??, including two types characterized as low and high vigor. Two studies were conducted. On the first, the effect of seed vigor on isolated plants, cultivated in hollows of 50 cm of depth, was evaluated. Two treatments were tested; plants originated from low and high vigor seeds, being each parcel composed by only one plant. On the second study, the evaluation was on the individual behavior of plants inside a population, as long as the entire population behavior established with different systems of distribution of plants originated from high and low vigor seeds, on the seed line. The experiment had 5 different combinations of seed line distribution of the plants originated from high and low vigor seeds, in seed lines of 4 meters of length. The plants were obtained by sowing each lot in distinct treys with soil as subtract...

‣ Variabilidade gen??tica e a efici??ncia de sele????o no car??ter dorm??ncia de sementes em aveia-preta(Avena strigosa Schreb.); Genetic variability and breeding efficiency for seed dormancy in blac oat (Avena strigosa Schreb.)

MOLITERNO, Enrique Alfredo Parachu
Fonte: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR Publicador: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR
Tipo: Tese de Doutorado Formato: application/pdf
Português
Relevância na Pesquisa
46.86472%
Seed dormancy is a trait shown by a large variety of weedy plants, which helps the purpose of perpetuating the species through space and time by delaying germination until specific environmental cues happen. Black oat, a temperate forage grass, is widely used for pasture and as a cover crop in minimum tillage systems in Southern Brazil. However, the largest portion of the seed sown belongs to an old variety, which has no genetic identity, contributing to the appearance of undesirable agronomic traits in a crop species such as seed dormancy. This trait is hold responsible for turning black oat into a potential weedy species in areas sown to other cool season cereals, such as wheat and barley. Three methods were used to screen and select for black oat genotypes expressing low seed dormancy, i.e. screening of lines collected throughout different agricultural regions of the state of Rio Grande do Sul; subjecting a specific line of the species to the effects of two chemical and one physical mutagens and crossbreeding between selected lines and commercial cultivars of the species. All three methods were undertaken under a glasshouse environment (without temperature control), and since there are no known vegetative morphological traits associated to seed dormancy the procedure consisted on selecting seedlings from non dormant seeds. These were grown in the glasshouse environment and their progeny seeds tested for germinability...

‣ Avalia????o t??cnica e comercial da empresa Sementes Iru??a - Paraguai; Technical and commercial evaluation of Iru??a Seeds company - Paraguay

RODRIGUES, Claiton
Fonte: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR Publicador: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
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The seeds company Iru??a is located at km 162, Cruce Raul Pe??a, in Alta Parana state Paraguay. It has begun its seeds production activities in 1983 with the commercialization of 3.129 forty kilos bags of soy seeds. Lately, the foreseen commercialization of seeds is approximately to 4.400 t of soy seeds and 2.500 t of wheat seeds. Internally, the intended seed commercialization until 2011 is 8.000 t of soy seeds and 4.000 t of wheat seeds. This paper intended a technical and commercial evaluation of the company with an emphasis on the soy crop abtaing a helpful data base for the company s decision makess, so to reach the stipulated goals. It was gathered data of what was produced internally during the period of 1983-2008. To reach the stipulated goal, problems such as the company s high discard after conditioning which is around 18,17%/year, average, must be lowered. It was observed the need in bedbug damage control and mechanical damages, which according to historical average is 17,3% for bedbugs and 12,4% levels for mechanical damages. The harvest of seeds with low humidity influenced negatively the seeds quality. Historically, 61,32% of the soy seed volume was harvested with less than 13% of humidity. The usage of inadequate machinery as inappropriate metallic commercial silos for seeds decreased the quality of soy seeds. The benefit of fields for seeds...

‣ Vigor de sementes e desempenho de campo de arroz h??brido; Hybrid rice seed vigor and culture performance

NEVES, M??rcio Blanco das
Fonte: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR Publicador: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
46.879287%
The aim of this study was to evaluate the effect of seed vigor on hybrid rice plant performance, grown in communities consisting of different combinations of plants originated from different vigor levels seeds along the line of seeding, individually or in arrangements of plants. Two experiments were conducted at the Experimental and Didactic Plant Science Department, Faculty of Agronomy "Eliseu Maciel . Two batches of hybrid rice seed from the RiceTec Company, Avaxi CL ??, characterized as high and low vigor were used for this aim. The first experiment evaluated the effect of seed vigor on the behavior of individually analyzed plants grown at different population densities. It was tested three different arrangements of plants: exclusive plants from high vigor seeds, exclusive plants from low vigor seeds, and half plants from high vigor seeds interspersed with half of plants from low vigor seeds. The arrangements were distributed in two densities: 125 plants per square meter and 63 plants per square meter. In the second study, the rice plants had their behavior evaluated individually within the community, and also, the general behavior of the community, formed by arrangements of plants from high and low vigor seeds in accordance the ratio of 100:0...

‣ Longevidade de sementes de arroz e de bi??tipos vermelho e preto no solo; Seed longevity of rice cultivars, strawhull and blackhull biotypes into the soil

Amato, Ana Laura Pereira
Fonte: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR Publicador: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR
Tipo: Tese de Doutorado Formato: application/pdf
Português
Relevância na Pesquisa
46.86472%
RACT. The objective was to evaluate seed longevity of rice cultivars, strawhull (SH) and blackhull (BH) biotypes in soil seed bank of the main rice production area of Uruguay. Longevity of seeds buried in June 1993 was evaluated in two experiments: - experiment 1 (EXP1) with seeds of the rice cultivars El Paso 144, INIA Tacuar?? and EEA 404; - experiment 2 (EXP2) with seeds of SH and BH. A split-plot experimental design was used with three replications in both experiments, were burial depths of 5 or 15 cm treatments were located in the big plots. In EXP1, burial time treatments of 10years for El Paso 144 and 5 years for INIA Tacuar?? and EEA 404 were located in the subplots, where cultivars were considered as subsubplots. In EXP2, biotypes treatments were located in the subplots and buried for 20 years. Each treatment consisted of 200 seeds buried in PVC open cylinders. Seeds were exhumed for the first time in September 1993, after three months of burial. After that, seeds were exhumed on the same date each year until no viable seeds were found. Exhumed seeds were classified for viability and dormancy by germination and tetrazolium tests. SH and BH biotypes seed samples were classified for percentage of viable seeds, dead seeds...

‣ Tamanho de sementes e danifica????o mec??nica em soja no estado do Paran??; Soybean seed size and mechanical damage in the state of Paran??

SILVA, Jos?? Donizeti da
Fonte: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR Publicador: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
46.879287%
This study aimed to determine the mechanical damage in soybean seeds and the efficiency of seed grading from samples collected at sowing time in the Paran?? state. For this study, it was used the method of sampling in drill box survey. The number of samples was determined for the Paran?? state, for a percentage of damage in soybean seeds of 20%, that 243 samples would be sufficient to estimate with 95% of probability this parameter of seed quality. The seeds evaluations were the mechanical damage and retention of small seeds with the large ones in the classification process. The mechanical seed damage was evaluated by the method of immersion in 5% sodium hypochlorite. According to this method, it was used 100 seeds which were soaked in the solution for 10 minutes. For the analysis of the retention of small seeds in the classification process, it was used 314 samples. For this process, two replicates of 100 seeds per sample were used. Based on the results, it was obtained the following conclusions: 1 - In the process of seed classification, over than 25% of the lots had more than 10% of small seeds that remain along with the large ones; 2 - Over than 50% of the seed lots, present more than 12% of mechanical damage; 3 - There are cultivars that are less affected by mechanical damage...

‣ Incrustamento em sementes de azev??m anual(Lolium multiflorum lam.): caracter??sticas f??sicas e qualidade fisiol??gica; Incrustamento em sementes de azev??m anual(Lolium multiflorum lam.): caracter??sticas f??sicas e qualidade fisiol??gica; Ryegrass (Lolium multiflorum Lam.) seed incrusting: physical characteristics and physiological quality of seeds; Ryegrass (Lolium multiflorum Lam.) seed incrusting: physical characteristics and physiological quality of seeds

PERES, Wilner Brod
Fonte: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR Publicador: Universidade Federal de Pelotas; Agronomia; Programa de P??s-gradua????o em Ci??ncia e Tecnologia de Sementes; UFPel; BR
Tipo: Tese de Doutorado Formato: application/pdf
Português
Relevância na Pesquisa
46.905176%
The objective of the present research was to increase ryegrass seed weight thought addition of inert materials by the process of incrusting (seed weight increase without change its form), to reduce drifting and to uniform its distribution improving it ballistic power when sowed by airplane. Two seed lots were used harvested in 2007/2008. After air separation to remove light materials and impurities, seeds were screened through two oblong holes screens: 1,2 x 20 mm and 0,8 x 12 mm, being used seeds over the 0,8 x 12 mm screen. Seeds were treated with insecticide Standak??, fungicide Vitavax?? - Thiram 200 SC and Giberellic acid ProGibb?? (10%). Inert materials used were Vermiculite and natural Phosphate of ARAD grinded and passed by n?? 100 screen. Adhesive materials were used Rigrantec polymers Polyseed 70?? and Polyseed CF?? diluted in water in proportion of 1:1. Those materials were added to the seeds in four individual layers including a drying period among each layer. The physical characteristics of seeds were determined by 1000 seeds weight, test weight, repose angle and terminal velocity. The physiological quality of the seeds was evaluated by the following tests: standard germination, first count of germination, accelerated ageing...