• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 9
  • Tagged with
  • 9
  • 9
  • 9
  • 7
  • 5
  • 4
  • 4
  • 4
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 2
  • 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.
1

Controle de qualidade de sementes de gergelim / The quality control of sesame seeds

Jesus, Lorena Le?o January 2014 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2014-12-22T15:33:12Z No. of bitstreams: 2 lorena_leao_jesus.pdf: 826450 bytes, checksum: 3a10a7ec4a4676a5ccb38e308ea778fb (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2014-12-22T15:33:34Z (GMT) No. of bitstreams: 2 lorena_leao_jesus.pdf: 826450 bytes, checksum: 3a10a7ec4a4676a5ccb38e308ea778fb (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2014-12-22T15:34:18Z (GMT) No. of bitstreams: 2 lorena_leao_jesus.pdf: 826450 bytes, checksum: 3a10a7ec4a4676a5ccb38e308ea778fb (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Made available in DSpace on 2014-12-22T15:34:18Z (GMT). No. of bitstreams: 2 lorena_leao_jesus.pdf: 826450 bytes, checksum: 3a10a7ec4a4676a5ccb38e308ea778fb (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Previous issue date: 2014 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes) / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / A cultura do gergelim, Sesamum indicum L., por possuir cerca de 50% de teor de ?leo em suas sementes, surge como uma alternativa para produ??o de biocombust?veis podendo competir com outras oleaginosas. No entanto, a utiliza??o de sementes de alta qualidade ? de fundamental import?ncia para o estabelecimento da cultura. Para a cultura do gergelim n?o existem metodologias adequadas para avalia??o da qualidade fisiol?gica de suas sementes. Objetivou-se com esta pesquisa adequar as metodologias dos testes de condutividade el?trica, envelhecimento acelerado, lixivia??o de pot?ssio e tetraz?lio para avalia??o da qualidade de sementes de gergelim. Foram testadas as metodologias do teste de condutividade el?trica utilizando embebi??o por 4, 8, 12, 16, 20 e 24 horas e combina??es n?mero de sementes/volume de ?gua deionizada (25/25 mL; 25/50 mL; 25/75 mL; 50/25 mL; 50/50 mL e 50/75 mL), para o teste de envelhecimento acelerado testou-se a metodologia tradicional com ?gua e com solu??o saturada de NaCl por 0, 24, 48, 72 e 96 horas, para o teste de lixivia??o de pot?ssio, embebi??o por 30, 60, 90, 120, 150 e 180 minutos, nas combina??es n?mero de sementes/volume de ?gua destilada (25/25 mL; 25/50 mL; 50/25 mL; 50/50 mL) e no teste de tetraz?lio foram testadas as concentra??es de 0,075%; 0,5% e 1,0% de solu??o de tetraz?lio a 25 ?C, por 3, 6, 8, 12, 18 e 24 horas. Concluiu-se que no teste de condutividade el?trica o per?odo de embebi??o de 4 horas e a combina??o de 25 sementes com 75 mL e 50 sementes com 75 mL ? eficiente para a distin??o da qualidade fisiol?gica de sementes de gergelim. Para o teste de envelhecimento acelerado o per?odo de envelhecimento de 48 horas pelo m?todo tradicional ou 72 horas e 96 horas com solu??o saturada de NaCl permite separar as cultivares de gergelim em diferentes n?veis de vigor. No teste de lixivia??o de pot?ssio a combina??o 25 sementes, 25 mL de ?gua e 60 minutos ou 90 minutos de embebi??o ? adequada para avalia??o do potencial fisiol?gico das sementes. A embebi??o das sementes sobre papel por 60 minutos, seguida de corte longitudinal e imers?o em solu??o de tetraz?lio na concentra??o de 0,075% por 12 horas e 1,0% por 3 horas ? eficiente na avalia??o da viabilidade das sementes de gergelim. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2014. / ABSTRACT The culture of, Sesamum indicum L., possess a circa of 50% content of oil within the seeds, surge as an alternative for the production of biofuels able to compete with other oilseeds. However, the utilization of high quality seeds is of fundamental importance for the establishment of cultivation. For the cultivation of sesame seeds, there exists no adapted methodologies for the evaluation of physical quality of the seeds. The objective of this study is to adapt a methodology to tests of electrical conductivity, accelerated aging, tetrazolium and potassium leachate to evaluate the quality of the seeds. The methodology of the electrical conductivity test were tested using imbibition for 4, 8, 12, 16, 20 and 24 hours and a number of combinations of seeds/volume in deionized water (25/25 mL; 25/50 mL; 25/75 mL; 50/25 mL; 50/50 mL e 50/75 mL), for the accelerated aging test tested the traditional methodology applied was with water and saturated solution NaCl for 0, 24, 48, 72 and 96 hours, for potassium leachate, imbibition for 30, 60, 90, 120 and 180 minutes with a number of combinations of seeds/volume in distilled water (25/25 mL; 25/50 mL; 50/25 mL and 50/50 mL) and tetrazolium test concentrations were 0.075%, 0.5% and 1.0% of the tetrazolium solution, at 25 ?C, for 3, 6, 8, 12, 18 and 24 hours. The conclusion of the electrical conductivity test demonstrate that the period of imbibition for 4 hours and the combination of 25 seeds with 75 mL of water and 50 seeds with 75 mL of water is efficient for the distinction of the physiological quality of the sesame seeds. For the test of accelerated aging, the period of aging for 48 hours by the traditional method or 72 hours and 96 hours with the saturated solution NaCl, permits the separation of the cultivars of sesame seeds in different levels of vigor. In the potassium leachate test, a combination of 25 seeds with 25 mL of water for 60 minutes or 90 minutes of imbibition is adequate for the evaluation of the physiological potential of the seeds. The imbibition of the seeds on paper for 60 minutes, following a longitudinal cut and immersion in the tetrazolium solution with a concentration of 0.075% for 12 hours and 1.0% for 3 hours is efficient in the evaluation of the viability of the sesame seeds.
2

Adequa??es metodol?gicas para os testes de vigor em sementes de Brachiaria brizantha. / Methodological adjustments to the vigor tests in Brachiaria brizantha seeds.

Oliveira, Ariadne Santos 01 February 2013 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-27T13:30:35Z No. of bitstreams: 5 41.pdf: 467693 bytes, checksum: 46ea478cf12119fee773189de4a6bf91 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-27T18:50:14Z (GMT) No. of bitstreams: 5 41.pdf: 467693 bytes, checksum: 46ea478cf12119fee773189de4a6bf91 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Made available in DSpace on 2015-02-27T18:50:14Z (GMT). No. of bitstreams: 5 41.pdf: 467693 bytes, checksum: 46ea478cf12119fee773189de4a6bf91 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) Previous issue date: 2013 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes) / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / Dentre as esp?cies mais utilizadas na implanta??o de pastagens est?o as do g?nero Brachiaria. Os benef?cios do uso de sementes de alta qualidade para forma??o de pastagem podem ser facilmente constatados pelo r?pido estabelecimento da forrageira, pastagem formada uniformemente e cobertura mais r?pida do solo, resultando em uma utiliza??o da pastagem em menor espa?o de tempo. Por?m, as metodologias utilizadas para avaliar a qualidade de suas sementes ainda n?o est?o bem definidas. O uso de testes de vigor ? uma ferramenta imprescind?vel para a avalia??o do potencial fisiol?gico dos lotes de sementes. Assim, objetivou-se com este estudo adequar os testes de envelhecimento acelerado e de condutividade el?trica, para avaliar o potencial fisiol?gico de lotes de sementes de Brachiaria brizantha das cultivares Marandu e Xara?s, cada uma delas representada por quatro lotes. Para o teste de envelhecimento acelerado as sementes foram submetidas ao envelhecimento acelerado tradicional e com solu??o saturada de NaCl, em cinco per?odos de envelhecimento, 0; 24; 48; 72 e 96 horas. Para o teste de condutividade el?trica, as sementes foram submetidas a 12 per?odos de imers?o em ?gua, por 2; 4; 6; 8; 10; 12; 14; 16; 18; 20; 22 e 24 horas, utilizando-se 25 sementes em 25 mL e em 50 mL, 50 sementes em 50 mL e em 75 mL de ?gua. Para caracterizar o perfil dos lotes, foi determinado o grau de umidade, os testes de germina??o, primeira contagem da germina??o, ?ndice de velocidade de germina??o, estande inicial, emerg?ncia e ?ndice de velocidade de emerg?ncia. Conclui-se que o teste de envelhecimento acelerado possibilita a separa??o dos lotes de B. brinzatha cv. Marandu e cv. Xara?s, pelo m?todo com solu??o saturada de NaCl por 72 horas e 24 horas, respectivamente. No teste de condutividade el?trica, o per?odo de imers?o de 14 horas, utilizando-se 50 sementes em 50 mL, para a cv Marandu, e utilizando-se 25 sementes em 25 mL ou 50 sementes em 50 mL de ?gua, para a cv Xara?s ? adequado para avalia??o do potencial fisiol?gico das sementes. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2013. / ABSTRACT Among the species most commonly used in the implementation of the pastures are of the genus Brachiaria. The benefits of using high quality seeds for pasture formation can be easily found by the rapid establishment of forage, pasture formed uniformly and cover the ground more quickly, resulting in a pasture utilization in shorter time. However, the methodologies used to evaluate the quality of their seeds are still poorly defined. The use of vigor testing is an essential implement for the evaluation of the physiological potential of seed lots. The objective of this research was adjust the accelerated aging tests and electrical conductivity, to evaluate the physiological potential of seed lots from Brachiaria brizantha Marandu and Xara?s cultivars, each represented by four lots. For the accelerated aging test, seeds were submitted to traditional accelerated aging and with saturated NaCl solution, five periods of aging, 0, 24, 48, 72 and 96 hours. For the electrical conductivity test, seeds were submitted to 12 periods of imbibitions in water for 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22 and 24 hours, using samples of 25 seeds in 25 mL and 50 mL, 50 seeds in 50 mL and 75 mL of water. To characterize the profile of lots, were determined moisture content, germination tests, first count of germination, speed of germination, initial stand, emergence, and? speed of emergence index. The accelerated aging test makes possible the separation of lots of B. brinzatha cv Marandu and cv Xara?s by the method with saturated NaCl solution for 72 hours and 24 hours, respectively. For the electrical conductivity test, the imbebition period during 14 hours using 50 seeds in 50 mL to Marandu and using 25 seeds in 25 mL or 50 seeds in 50 mL of water for cultivar Xara?s is appropriate for evaluating the seed physiological potential.
3

Testes de vigor para avalia??o da qualidade de sementes de crambe (Crambe abyssinica Hochst). / Vigor tests assessing the quality of crambe seeds.

Cruz, Sara Michelly 19 February 2013 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-27T13:30:36Z No. of bitstreams: 5 54.pdf: 760236 bytes, checksum: c96473cb1f96d0ebd32276b921d2f10d (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-27T19:26:35Z (GMT) No. of bitstreams: 5 54.pdf: 760236 bytes, checksum: c96473cb1f96d0ebd32276b921d2f10d (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Made available in DSpace on 2015-02-27T19:26:35Z (GMT). No. of bitstreams: 5 54.pdf: 760236 bytes, checksum: c96473cb1f96d0ebd32276b921d2f10d (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) Previous issue date: 2013 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes) / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / A cultura do crambe (Crambe abyssinica Hochst) tem se destacado no cen?rio nacional pelo seu potencial para produ??o de biodiesel devido ? facilidade de cultivo, qualidade do ?leo e possibilidades de uso dos subprodutos da extra??o do ?leo. Para o estabelecimento da cultura no pa?s ? necess?rio que sejam usadas sementes de qualidade. No entanto, as informa??es sobre metodologias para avalia??o da qualidade de sementes dessa cultura s?o escassas. Dessa forma, objetivou-se adequar as metodologias dos testes de envelhecimento acelerado e condutividade el?trica para avalia??o do vigor de sementes de crambe e investigar a atividade enzim?tica em rela??o ?s diferen?as de vigor. Foram utilizados cinco lotes de sementes da cultivar FMS Brilhante das safras 2008, 2009, 2010 e 2011. Foram realizadas a caracteriza??o morfol?gica de sementes e pl?ntulas e a composi??o centesimal da semente de crambe. Para caracteriza??o do perfil dos lotes realizou-se a determina??o do grau de umidade e os testes de primeira contagem de germina??o, germina??o, ?ndice de velocidade de germina??o, emerg?ncia, estande inicial, ?ndice de velocidade de emerg?ncia e sanidade. Foi tamb?m realizada a an?lise eletrofor?tica das isoenzimas super?xido dismutase, esterase, catalase, ?lcool desidrogenase e malato desidrogenase. Para o teste de envelhecimento acelerado, as sementes foram submetidas ao m?todo tradicional e com solu??o saturada de NaCl, pelos per?odos de envelhecimento de 0; 24; 48; 72 e 96 horas. No teste de condutividade el?trica, as sementes foram submetidas aos per?odos de 2; 4; 6; 8; 10; 12; 14; 16 e 18 horas de embebi??o utilizando-se 25 sementes em 25 mL e 50 mL e 50 sementes em 50 mL e 75 mL. Concluiu-se que ? poss?vel avaliar o vigor de sementes de crambe pelo m?todo tradicional do teste de envelhecimento acelerado a 42 ?C por 96 horas. O teste de condutividade el?trica n?o foi adequado para avalia??o da qualidade fisiol?gica de crambe. Quando associado ? atividade das isoenzimas observou-se que o lote de maior vigor teve maior atividade dos grupos enzim?ticos super?xido dismutase, catalase e esterase. O lote de menor vigor n?o teve atividade das enzimas isocitrato liase e ?lcool desidrogenase. N?o houve altera??o na atividade da isoenzima malato desidrogenase. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2013. / ABSTRACT Crambe (Crambe abyssinica Hochst) has been highlighted in the national scenery for its potential in producing biodiesel due to its ease of cultivation, quality of the oil and possibilities of use of the oil extraction byproducts. In order to establish the culture in the Country, the use of quality seeds is necessary. However, the information on methodologies for seed quality evaluation for this culture is scarce. Thus, we aimed at adapting the methodologies to the accelerated aging and electric conductivity tests to evaluate the vigor of crambe seeds and investigate the enzymatic activity in relation to the vigor differences. Five seed lots of cultivar FMS Brilhante of the 2008, 2009, 2010 and 2011 harvests were used. We performed the morphologic characterization of seeds and seedlings and the centesimal composition of crambe seeds. For the profile characterization of the lots, we performed the determination of the humidity degree and the tests for first germination count, germination, germination speed index, emergence, initial stand, emergence speed index and sanity. We also performed the electrophoretic analysis of the superoxide dismutase, esterase, catalase, alcohol dehydrogenase and malate dehydrogenase isoenzymes. For the accelerated aging test, the seeds were submitted to the traditional method and with NaCl saturated solution, for the aging periods of 0; 24; 48; 72 and 96 hours. In the electrical conductivity test, the seeds were submitted to the periods of 2; 4; 6; 8; 10; 12; 14; 16 and 18 hours of soaking using 25 seeds in 25 mL and 50 mL, and 50 seeds in 50 mL and 75 mL. We concluded that it is possible to evaluate crambe seed vigor by the traditional method of the accelerated aging test at 42 oC for 96 hours. The electric conductivity test was not adequate for evaluating crambe physiological quality. When associated with isoenzymes activity, we observed that the lot with highest vigor presented the highest activity of the superoxide dismutase, catalase and esterase isoenzymes groups. The lot of lowest vigor did not present activity of the isocitrate liase and alcohol dehydrogenase enzymes. There was no interaction of the activity of the malate dehydrogenase isoenzymes.
4

Testes para a avalia??o da qualidade fisiol?gica de sementes de Moringa oleifera Lam

Medeiros, Maria Luiza de Souza 17 December 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-06-27T17:39:00Z No. of bitstreams: 1 MariaLuizaDeSouzaMedeiros_DISSERT.pdf: 778297 bytes, checksum: 3012a0a9e0e06a0f632900e02f88e311 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-06-29T20:16:49Z (GMT) No. of bitstreams: 1 MariaLuizaDeSouzaMedeiros_DISSERT.pdf: 778297 bytes, checksum: 3012a0a9e0e06a0f632900e02f88e311 (MD5) / Made available in DSpace on 2016-06-29T20:16:49Z (GMT). No. of bitstreams: 1 MariaLuizaDeSouzaMedeiros_DISSERT.pdf: 778297 bytes, checksum: 3012a0a9e0e06a0f632900e02f88e311 (MD5) Previous issue date: 2015-12-17 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A avalia??o do vigor de sementes ? um fator importante para a detec??o de lotes de sementes de alta qualidade, de modo que o desenvolvimento de procedimentos para avaliar o potencial fisiol?gico tem sido importante ferramenta dentro de programas de controle de qualidade de sementes. Nesse sentido, este trabalho teve como objetivo adequar as metodologias dos testes de envelhecimento acelerado, condutividade el?trica e lixivia??o de pot?ssio para a avalia??o do vigor de sementes de Moringa oleifera LAM.. Para tanto, quatro lotes de sementes foram submetidos aos testes de germina??o, emerg?ncia de pl?ntula, ?ndice de velocidade de emerg?ncia, primeira contagem de emerg?ncia, comprimento e massa seca de pl?ntulas e teste frio, para a sua caracteriza??o fisiol?gica, al?m dos testes de envelhecimento acelerado, condutividade el?trica e lixivia??o de pot?ssio. O delineamento experimental utilizado foi o inteiramente casualizado, com quatro repeti??es de 50 sementes, e as m?dias comparadas pelo teste de Tukey a 5% de probabilidade, sendo realizada a an?lise de regress?o polinomial no teste de condutividade el?trica. Para o teste de envelhecimento acelerado, foram estudados os per?odos de envelhecimento de 12, 24 e 72 horas, a 40, 42 e 45 ?C. Para o teste de condutividade el?trica, utilizou-se a temperatura de 25 ?C por per?odos de 4, 8, 12, 16 e 24 horas de imers?o, em 75 e 125 mL de ?gua destilada, utilizando-se 25 e 50 sementes e, para o teste de lixivia??o de pot?ssio, utilizou-se amostras de 25 e 50 sementes, colocadas em copos pl?sticos contendo 70 e 100 mL de ?gua destilada ? 25 ?C por per?odos de 1, 2, 3, 4, 5 e 6 horas. A partir dos resultados obtidos, pode-se inferir que as metodologias que melhor se ajustaram para o teste de envelhecimento acelerado em sementes de moringa foram a temperatura de 40 ?C por 12 e 72 horas, 42 ?C a 72 horas e 45 ?C a 24 horas. Para o teste de condutividade el?trica em sementes de moringa, a combina??o de 50 sementes em 75 mL de ?gua destilada por per?odo de embebi??o de 4 horas e, 50 sementes em 125 ml por 4 horas foram eficiente para a diferencia??o dos lotes de sementes de moringa quanto ao vigor e, para o teste de lixivia??o de pot?ssio em sementes de moringa, a combina??o de 50 sementes /100 mL de ?gua destilada permitiu a separa??o dos lotes em quatro n?veis de vigor, a partir de 2 horas de imers?o, mostrando-se promissor na avalia??o da qualidade de sementes de moringa. / The evaluation of seed vigor is an important factor for detection of lots of high quality seeds, so that development of procedures to evaluate the physiological potential has been an important tool in quality control programs seeds. In this sense the study aimed to adapt the methodologies of accelerated aging, electrical conductivity and potassium leaching to evaluate Moringa oleifera seed vigor LAM.. Therefore, four lots of moringa seeds were subjected to the germination tests, seedling emergence, speed of emergence index, emergence first count, length and dry mass of seedlings and cold test for their physiological characterization, in addition to accelerated aging, electrical conductivity and potassium leaching. The experimental design was completely randomized with four replications of 50 seeds and the means compared by Tukey test at 5% probability. For accelerated aging the periods were studied aging 12, 24 and 72 hours at 40, 42 and 45?C. For the electrical conductivity test was used to a temperature of 25?C for periods of 4, 8, 12, 16 and 24 hours of immersion in 75 to 125 mL of distilled water, using 25 to 50 seeds, and for potassium leaching test samples were used 25 to 50 seeds, placed in plastic cups containing 70 and 100 mL of distilled water at 25?C for periods of 1, 2, 3, 4, 5 and 6 hours. From the results obtained, it can be inferred that the methods best fit for the accelerated aging test Moringa seeds were a temperature of 40?C for 12 to 72 hours, 42?C 72 hours 45?C 24 hours . In the electrical conductivity test Moringa seeds, the combination of 50 seeds in 75 mL distilled water for a period of immersion of 4 hours and 50 seeds in 125 mL of 4 hours were efficient for the differentiation of lots of Moringa seeds as to vigor and for potassium leaching test moringa seeds, the combination of 50 seeds in 100mL of distilled water allowed the separation of lots of four levels of vigor, at 2 hours of immersion, showing promise in evaluate the quality of moringa seeds.
5

Ocorr?ncia de leite inst?vel na regi?o semi?rida do Rio Grande do Norte e sua correla??o com a qualidade do leite

Faria, Priscilla Fernandes de 05 August 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-06-15T00:32:07Z No. of bitstreams: 1 PriscillaFernandesDeFaria_DISSERT.pdf: 470162 bytes, checksum: fa888637c9b8d78f143bf6e83736bce1 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-06-20T19:25:08Z (GMT) No. of bitstreams: 1 PriscillaFernandesDeFaria_DISSERT.pdf: 470162 bytes, checksum: fa888637c9b8d78f143bf6e83736bce1 (MD5) / Made available in DSpace on 2016-06-20T19:25:08Z (GMT). No. of bitstreams: 1 PriscillaFernandesDeFaria_DISSERT.pdf: 470162 bytes, checksum: fa888637c9b8d78f143bf6e83736bce1 (MD5) Previous issue date: 2015-08-05 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O objetivo deste trabalho foi identificar a ocorr?ncia de leite inst?vel n?o ?cido nasmesorregi?es oeste e central do Rio Grande do Norte, bem como avaliar a qualidade doleite. Foram analisadas 92 amostras, ao longo de 4 meses, provenientes de 23 tanques deresfriamento. Foi realizado o teste do ?lcool a 68%, 72% e 76%, al?m da mensura??o dopH, acidez, gordura, prote?na, s?lidos totais, nitrog?nio ureico, lactose, case?na e contagemde c?lulas som?ticas. A incid?ncia de LINA foi de 15,91%, e n?o houve diferen?asignificativa na composi??o do LINA em rela??o ao leite est?vel em nenhuma dasgradua??es alco?licas. Nenhuma amostra de LINA apresentou coagula??o na prova dafervura. Tais resultados permitem concluir que apesar das in?meras adversidades clim?ticase nutricionais existentes na regi?o, o LINA n?o representa um problema aparente / The unstable non acid milk (UNAM) is characterized by coagulation in the alcohol test and wanted acidity (14-18?D). Among Brazilian regions, the South and Southeast have the highest occurrence of LINA, which has been causing problems for both producers and for industries, due to the disposal or undervaluation of milk. In the Northeast there are few studies that indicate their occurrence and quality. The objective of this study was to identify the occurrence of unstable non-acid milk in the west and central mesoregions of Rio Grande do Norte, determine their physicochemical characteristics, test alcoholic graduations and evaluate their correlation with the quality of milk. 176 raw milk samples were analyzed in the period from September to December /2014 from 23 APASA?s cooling tanks, located in 7 cities of west and central mesoregions RN. The samples were collected in duplicate, one sample used for alcohol testing at 68, 72 and 76%, measurement of pH, acidity, electrical conductivity and boiling proof, made in LABOLEITE / UFRN; and the other sample containing Bronopol? preservative, was sent to the APCBRH (Cattle Breeders Association Paranaense Holstein) laboratory in Curitiba-PR, which were analyzed fat, protein, total solids, lactose, casein, urea nitrogen and somatic cell count. The test alcohol samples disapproved 31.82%, of which 30% proved to be non-acid, and 30% had high acidity. The samples were divided into three classes: Stable Milk, UNAM and acid milk. 3% Tukey test was used for comparison of stable milk components and UNAM and there was no significant difference between them. Both classes obtained averages within the standard required by IN 62. The average value of electric conductivity was 4.84 mS/cm for stable milk, 4.55 mS/cm for unstable and acid milk and 4.53 mS/cm for non-acid unstable milk. The electrical conductivity was positively correlated with alcohol stability of milk and negative correlation with acidity and pH. Could not observe direct relationship between the electrical conductivity and the somatic cell count.The boiling test was negative for all samples UNAM. It can be concluded that the incidence of UNAM in the studied region is low, although the predisposing factors such as heat stress, drought and nutritional deficiency. In conclusion, the UNAM has quality similar to stable milk, conform the norms required by Agriculture Ministry, and with adequate thermal stability, which proves that there is no reason to reject this milk by industry.
6

Impactos do estresse salino e da cobertura morta nas caracter?sticas qu?micas do solo e no desenvolvimento do amaranto / Impacts on the soil chemical characteristics and development of amaranth under saline stress and mulch

Costa, Djeson Mateus Alves da 30 November 2007 (has links)
Made available in DSpace on 2014-12-17T15:01:43Z (GMT). No. of bitstreams: 1 DjesonMAC.pdf: 1628748 bytes, checksum: b6ef63ced97de5a10b49f957a2292346 (MD5) Previous issue date: 2007-11-30 / Availability of good quality water has been reduced vertiginously, over the last decade, in the world. In some regions, the water resources have high concentration of the dissolved salts, these characteristics of the water make it s use impossible. Water quality can be a limitation for irrigated agriculture, principally in regions of arid or semiarid climate where the water resources are generally saline and are exposed at high evaporation ratio. For that reason, precipitation of the salts occurs near the soil surface and those salts themselves cumulate in the vegetal tissue, reducing the soil fertility and crop production. The adoption of tolerant crop to the water salinity and soil salinity, adaptable to the climatic conditions is other emergent necessity. This work had the goal of studying the effects of four salinity levels of the irrigation water salinity and use of mulch, dried leaves of Forest mangrove (Acacia mangiumWilld), in cultivated soil with amaranth (Amaranthus cruentus, BRS Alegria variety), in greenhouse. It was utilized the transplant of plants to PVC columns, containing 30 kg of silty loam soil, 10 days after emerging, with space of 50 x 50 cm between lines. Treatments were composed by combination of four levels of salinity (0.147; 1.500; 3.000 e 4.500 dS m-1), obtained by addition NaCl (commercial) to irrigation water and soil with and without protection, by mulch. A factorial system 4 x 2 was used with four repetitions, totalizing 32 parcels. The concentrations of nutrients in soil solution have been evaluated, in the dry matter of the vegetal tissue (roots, stem, leaves and raceme residue), at the end of the vegetative cycle. The use of soil protection reduced time for the beginning inflorescence of plants, at the same time, the increase of the salinity delayed this phase of amaranth development. The use of the mulch effectively increased the height, stem diameter, area of the larger leaf, humidity and dry matter content and amaranth grain production. The vegetal species showed salinity tolerance to experimented levels. The adopted treatments did not affect the pH values, exchangeable cation contents, electrical conductivity of soil solution (EC1:5) and saturated extract (ECSE), and Ca+2, Mg+, Fe+2 and Mn+2 contents, in the soil solution. The increase of the salinity concentration in the irrigation water inhibited the mineralization process of the organic matter (OM) and, consequently, the efficiency in the it?s utilization by plants, at the same time, produced increase in the values of the exchangeable sodium percentage (ESP), sodium adsorption ratio (SAR) and potassium adsorption ratio (PAR), in the soil solution. Therefore, the use of the mulch did not affect the first three parameters. The protein and nutrient contents: K+, Ca+2, P, Mg+2 e Cu+2, in amaranth grains, were improved by tillage condition. The raceme residues showed chemical/nutritional composition that makes advantageous its application in animal ration. In this context, it follows that amaranth tolerate the saline stress, of the irrigation water, until 4.500 dS m-1, temperature and relative humidity of the air predominant in the experimental environment / A disponibilidade de ?gua de boa qualidade tem diminu?do vertiginosamente nas ?ltimas d?cadas, em todo o mundo. Em algumas regi?es os recursos h?dricos dispon?veis apresentam altos teores de sais dissolvidos, inviabilizando a sua utiliza??o. A qualidade da ?gua pode ser um fator limitante para a agricultura irrigada, principalmente nas regi?es de clima ?rido ou semi-?rido onde os recursos h?dricos s?o geralmente salinos e se encontram expostos a altas taxas de evapora??o que ocasiona a precipita??o de sais na superf?cie do solo e ac?mulo no tecido vegetal, diminuindo, respectivamente, a fertilidade e o rendimento da cultura. Logo, a ado??o de cultivares tolerantes ? salinidade da ?gua de irriga??o e do solo, assim como, resistentes ?s condi??es clim?ticas ? outra necessidade emergente na atualidade. Este trabalho teve o objetivo de estudar os efeitos de quatro n?veis de salinidade da ?gua de irriga??o e da cobertura morta, folhas secas de ac?cia (Acacia mangiumWilld), em solo cultivado com amaranto (Amaranthus cruentus, variedade BRS Alegria), conduzido em casa de vegeta??o. Foi utilizado o sistema de forma??o de mudas, transplantadas 10 dias ap?s emerg?ncia para colunas de PVC contendo 30 kg de solo franco-siltoso, no espa?amento de 0,50 x 0,50 m. Os tratamentos foram compostos pela combina??o de quatro n?veis de salinidade (0,147; 1,500; 3,000 e 4,500 dS m-1), obtidos pela adi??o de NaCl (comercial) ? ?gua de irriga??o, e solo com e sem prote??o por cobertura morta. Utilizou-se um arranjo fatorial 4x2 com quatro repeti??es, perfazendo um total de 32 parcelas. Foram avaliados os teores de nutrientes presentes na solu??o do solo e na mat?ria seca do tecido vegetal (ra?zes, caule, folhas, gr?os e res?duo de pan?cula), ao final do ciclo vegetativo. O uso de prote??o do solo reduziu o tempo para o in?cio da flora??o das plantas, ao mesmo tempo em que o aumento da salinidade retardou essa fase do desenvolvimento do amaranto. O uso da prote??o do solo proporcionou aumentos significativos na altura, no di?metro de caule, na ?rea da folha mais desenvolvida, na quantidade de mat?ria fresca e seca e na produ??o de gr?os do amaranto. A esp?cie vegetal apresentou toler?ncia ? salinidade, para os n?veis experimentados. Os tratamentos adotados n?o afetaram os valores de pH, capacidade de troca de c?tions (CTC), condutividade el?trica da solu??o do solo (CE1:5) e extrato saturado (CEES), e teores de Ca+2, Mg+2, Fe+2 e Mn+2, na solu??o de solo. O aumento da concentra??o salina na ?gua de irriga??o inibiu o processo de mineraliza??o da mat?ria org?nica (MO) e, consequentemente, a efici?ncia de seu aproveitamento pelas plantas, ao mesmo tempo em que provocou aumento nos valores da porcentagem de s?dio troc?vel (PST), da raz?o de adsor??o de s?dio (RAS) e de pot?ssio (RAP) na solu??o de solo. No entanto, o uso de prote??o do solo n?o afetou os tr?s primeiros fatores. Os teores de prote?na bruta e dos nutrientes: K+, Ca+2, P, Mg+2 e Cu+2, nos gr?os do amaranto, foram beneficiados pelas condi??es de cultivo. Os res?duos de pan?culas apresentaram composi??o qu?mica/nutricional que favorece a sua utiliza??o como complemento para ra??o animal. Neste contexto, pode-se concluir que o amaranto ? tolerante ao estresse salino, da ?gua de irriga??o, at? o n?vel de 4,500 dS m-1 e ?s condi??es de temperatura e umidade relativa do ar predominantes no ambiente experimental
7

Uma proposta de integra??o curricular entre o ensino de f?sica e o tema solos no curso t?cnico em meio ambiente do Instituto Federal do Amap? - campus Laranjal do Jari / A proposal for curriculum integration between physical education and the theme soils in the technical course in the environment of the Federal Institute of Amap? - campus Laranjal of the Jari

ALMEIDA, Willians Lopes de 28 July 2016 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-08-04T17:38:06Z No. of bitstreams: 1 2016 - Willians Lopes de Almeida.pdf: 1770532 bytes, checksum: d6cb976721bbde35acc6e8eb811e7c46 (MD5) / Made available in DSpace on 2017-08-04T17:38:06Z (GMT). No. of bitstreams: 1 2016 - Willians Lopes de Almeida.pdf: 1770532 bytes, checksum: d6cb976721bbde35acc6e8eb811e7c46 (MD5) Previous issue date: 2016-07-28 / The concepts and laws of physics are widely used in research aimed at improving environmental quality, providing theoretical bases / practical solution to the problems of the environmental pollution. Such problems are made up of various aspects ranging from contamination of water, air and soil, to landscape changes. On the ground, this is not just a piece of ground; it is very complex and consists of several elements such as organic matter, water, air and especially life. Considering the importance that the study of soil has been the need to bring this knowledge to the basic cycle of education, in order to wake up early on the aspects of the practice of conscious use of this ecosystem element. Given this, it is clear that there is a range of possibilities to work with the subject in the school context, given its importance, ease of viewing changes resulting from the misuse or disorderly occupation of land and also its transdisciplinary character. One such possibility is the soil resistivity of the study, which harnesses knowledge of physics, as well as composition and soil contamination. Many students question the importance of studying physics considering that this curriculum component will not be useful to you in your everyday life or professional activities. In this perspective, thinking teaching strategies that engage students in both their educational background as a professional in order to make them recognize the role of science in the transformation of society, it is the role that the teacher has and his commitment to each education better. Thus, with the support of the theory of meaningful learning, could be assessed, opposite the existing transdisciplinary relationship between physical and thematic soil, through the study of soil electrical resistivity in a low cost experiment, recognition and learning more dynamically and satisfactory. Based on the results it can be said that the transdisciplinary proposal, through experimentation, from the concept of electrical resistivity as curriculum integration component between physics and soil, was successful, given the good evaluation that students employed in job. The role of experimentation in the teaching-learning process in physical education, in this context, reflected in improvements in student learning and made them recognize the relationships between the two curriculum components: physical and soils. The methodological strategy used in this study contributed to the characterization of vocational training in the technical environment and this allowed the study subjects were able to understand the content taught in a more meaningful way. The results obtained in the post-test and evaluation of the work by the students, it was found that they have recognized the significance of the concept of soil electrical resistivity and experienced a significant learning, given all the context that passed during the execution of this research. / Os conceitos e leis da f?sica s?o amplamente utilizados em pesquisas que visam melhorar a qualidade ambiental, proporcionando bases te?rico/pr?ticas para solu??o dos problemas decorrentes da polui??o do meio ambiente. Tais problemas s?o constitu?dos por diversos aspectos que v?o desde a contamina??o da ?gua, do ar e do solo, at? a modifica??o da paisagem. Em rela??o ao solo, este n?o se resume a um peda?o de ch?o; ele ? bastante complexo e constitu?do por diversos elementos como mat?ria org?nica, ?gua, ar e, principalmente, vida. Considerando a import?ncia que o estudo do solo tem, vem a necessidade de levar este conhecimento ao ciclo b?sico da educa??o, de modo a despertar desde cedo os aspectos relativos ? pr?tica consciente de utiliza??o deste elemento do ecossistema. Diante disto, percebe-se que h? um leque de possibilidades para se trabalhar o tema no contexto escolar, dada a sua import?ncia, facilidade de visualizar modifica??es decorrentes do mau uso ou ocupa??es desordenadas da terra e tamb?m o seu car?ter transdisciplinar. Uma dessas possibilidades est? no estudo da resistividade do solo, a qual atrela conhecimentos de f?sica, bem como de composi??o e contamina??o do solo. Muitos alunos questionam a import?ncia de se estudar f?sica considerando que este componente curricular n?o lhe ser? ?til em sua vida cotidiana ou atua??o profissional. Nessa perspectiva, pensar estrat?gias de ensino que envolva os alunos, tanto em seu contexto formativo como profissional, de modo a faz?-los reconhecer o papel da ci?ncia na transforma??o da sociedade, representa a fun??o que o educador tem e seu compromisso com uma educa??o cada vez melhor. Assim, com apoio da teoria da aprendizagem significativa, foi poss?vel avaliar, frente ? rela??o transdisciplinar existente entre a f?sica e a tem?tica solos, atrav?s do estudo da resistividade el?trica do solo num experimento de baixo custo, o reconhecimento e a aprendizagem de forma mais din?mica e satisfat?ria. Com base nos resultados pode-se dizer que a proposta transdisciplinar, por meio da experimenta??o, a partir do conceito de resistividade el?trica como componente de integra??o curricular entre a f?sica e solos, foi bem sucedida, haja vista a boa avalia??o que os alunos empregaram no trabalho. O papel da experimenta??o no processo de ensino-aprendizagem no ensino de f?sica, para este contexto, repercutiu em melhorias na aprendizagem dos alunos e os fizeram reconhecer as rela??es entre os dois componentes curriculares: f?sica e solos. A estrat?gia metodol?gica utilizada neste trabalho contribuiu com a caracteriza??o da forma??o profissional do t?cnico em meio ambiente e isto permitiu que os sujeitos pesquisados conseguissem compreender o conte?do ensinado de forma mais significativa. Atrav?s dos resultados obtidos no p?s-teste e na avalia??o do trabalho por parte dos alunos, foi poss?vel constatar que estes reconheceram a signific?ncia do conceito de resistividade el?trica do solo e experimentaram uma aprendizagem significativa, dado todo contexto que passaram ao longo da execu??o desta pesquisa.
8

Obten??o e Caracteriza??o F?sico-Qu?mica do Sistema Comp?sito PEG-TiO2

Maria, Roberta Patr?cia Medeiros de 24 February 2011 (has links)
Made available in DSpace on 2014-12-17T15:41:57Z (GMT). No. of bitstreams: 1 RobertaPMM_DISSERT.pdf: 3172444 bytes, checksum: 159d519d0473cdce848696ecb3f8e8f6 (MD5) Previous issue date: 2011-02-24 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Hybrid systems formed from polymers and transition metals have now their physical and chemical properties extensively investigated for use in electronic devices. In this work, Titanium Dioxide (TiO2) from the precursor of titanium tetrabutoxide and the composite system Poly(Ethylene Glycol)-Titanium Dioxide (TiO2-PEG) were synthesized by sol-gel method. The PEG as acquired and TiO2 and composites powders were analyzed by X-Ray Diffraction (XRD), Spectroscopy in the Infrared region with Fourier transform (IRFT), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM) and Electrochemical Impedance Spectroscopy (EIS). In the XRD analysis were observed in the TiO2 crystal faces of one of its polymorphs - anatase phase, crystal planes in Poly (Ethylene Glycol) with considerable intensity and in the composite systems the mixture of crystal faces of their precursors isolated and reduction of crystallinity. The TG / DTG suggested increasing the thermal instability of PEG in the composite powders as TiO2 is incorporated into the system. Spectral analysis presented in the infrared overlapping bands for the polymer and metal oxide, reducing the intensity of symmetric stretching of ligand groups in the main chain polymer and angular deformations; were observed using SEM micrographs of the morphological changes suffered by composite systems with the variation of the oxide concentration. Analyses by impedance spectroscopy indicated that the increased conductivity in composite occurs in line with the addition of the metal oxide concentration in the composite system / Sistemas h?bridos formados a partir de pol?meros e metais de transi??o atualmente t?m suas propriedades f?sicas e qu?micas extensivamente investigadas para aplica??o em dispositivos eletr?nicos. Neste trabalho, o Di?xido de Tit?nio (TiO2) a partir do precursor Tetrabut?xido de Tit?nio e o sistema comp?sito Poli (Etileno Glicol)-Di?xido de Tit?nio (PEG-TiO2) foram sintetizados pelo m?todo sol-gel. O PEG como adquirido e os p?s de TiO2 e comp?sitos obtidos foram analisados por Difra??o de Raios X (DRX), Espectroscopia de Absor??o na regi?o do Infravermelho com Transformada de Fourier (EIV-TF), An?lise Termogravim?trica (TG), Microscopia Eletr?nica de Varredura (MEV) e Espectroscopia de Imped?ncia Eletroqu?mica (EIE). Nas an?lises por DRX foram observadas no TiO2, faces cristalinas de um de seus polimorfos fase anat?sio, planos cristalinos no PEG com intensidade substancial e nos sistemas comp?sitos a mistura de faces cristalinas dos seus precursores na forma isolada, bem como, redu??o da cristalinidade. As curvas TG/DTG sugeriram o aumento da instabilidade t?rmica do PEG nos p?s comp?sitos ? medida que TiO2 ? incorporado ao sistema. A an?lise espectral na regi?o do infravermelho apresentou sobreposi??o de bandas relativas ao pol?mero e ao ?xido met?lico, redu??o da intensidade de estiramentos sim?tricos dos grupos ligantes da cadeia principal polim?rica e deforma??es angulares; foram observadas atrav?s das micrografias de MEV modifica??es morfol?gicas sofridas pelos sistemas comp?sitos com a varia??o da concentra??o do ?xido. As an?lises por imped?ncia eletroqu?mica indicaram que o aumento da condutividade nos comp?sitos ocorre em conson?ncia com a adi??o da concentra??o do ?xido met?lico no sistema comp?sito
9

Testes bioqu?micos para avalia??o do vigor em sementes de Mimosa caesalpiniaefolia Benth

Avelino, Mirella Carvalho Souza 21 March 2014 (has links)
Made available in DSpace on 2014-12-17T14:17:54Z (GMT). No. of bitstreams: 1 MirellaCSA_DISSERT.pdf: 648930 bytes, checksum: 06627ea14cbf2543775d82cecd4ee6ec (MD5) Previous issue date: 2014-03-21 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Mimosa caesalpiniaefolia Benth. is a forest species of the Mimosaceae family, recommended for recovery of degraded areas. The evaluation of vigor by biochemical tests have been an important tool in the control of seed quality programs, and the electrical conductivity and potassium leaching the most efficient in the verifying the physiological potential. The objective, therefore, to adjust the methodology of the electrical conductivity test for seeds of M. caesalpiniaefolia, for then compare the efficiency of this test with the potassium in the evaluation of seed vigor of different lots of seeds M. caesalpiniaefolia. To test the adequacy of the electrical conductivity were used different combinations of temperatures , 25 ?C and 30 ?C, number of seeds , 25 and 50, periods of imbibition , 4 , 8 , 12 , 16 and 24 hours , and volumes deionized water, 50 mL and 75mL. For potassium leaching test, which was conducted from the results achieved by the methodology of the adequacy of the electrical conductivity test, to compare the efficiency of both tests , in the classification of seeds at different levels of vigor, and the period 4 hours also evaluated because the potassium leaching test can be more efficient in the shortest time . The best combination obtained in experiment of electrical conductivity is 25 seeds soaked in 50 mL deionized or distilled water for 8 hours at a temperature of 30 ? C. Data were subjected to analysis of variance, the means were compared with each other by F tests and Tukey at 5 % probability, and when necessary polynomial regression analysis was performed. The electrical conductivity test performed at period eight hour proved to be more efficient in the separation of seed lots M. caesalpiniaefolia at different levels of vigor compared to the potassium test / Mimosa caesalpiniaefolia Benth. ? uma esp?cie florestal pertencente ? fam?lia Mimosaceae, recomendada para recomposi??o de ?reas degradadas. A avalia??o do vigor por meio de testes bioqu?micos tem sido importante ferramenta dentro de programas de controle de qualidade de sementes, sendo os testes de condutividade el?trica e lixivia??o de pot?ssio um dos mais utilizados na verifica??o do potencial fisiol?gico. Objetivou-se, portanto, adequar a metodologia do teste de condutividade el?trica para sementes de M. caesalpiniaefolia, para ent?o comparar a efici?ncia deste teste com o de lixivia??o de pot?ssio na avalia??o de vigor das sementes dos diferentes lotes de M. caesalpiniaefolia. Para o teste de adequa??o da condutividade el?trica foram utilizadas diferentes combina??es de temperaturas, 25 e 30 ?C, de n?mero de sementes, 25 e 50, de per?odos de tempo de embebi??o, 4, 8, 12, 16 e 24 horas, e de volumes de ?gua deionizada, 50 e 75 mL. Para o teste de lixivia??o de pot?ssio, que foi realizado a partir dos resultados alcan?ados pela metodologia da adequa??o do teste de condutividade el?trica, p?de-se comparar a efici?ncia de ambos os testes, na classifica??o dos lotes das sementes em diferentes n?veis de vigor, sendo o per?odo de 4 horas tamb?m avaliado devido o teste de lixivia??o de pot?ssio poder ser mais eficiente em menor espa?o de tempo. A melhor combina??o obtida no experimento de adequa??o da condutividade el?trica ? a combina??o de 25 sementes embebidas em 50 mL de ?gua deionizada durante 8 horas a uma temperatura de 30 ?C. Os dados foram submetidos ? an?lise de vari?ncia, as m?dias comparadas entre si pelos testes F e de Tukey a 5% de probabilidade, e quando necess?rio foi realizada an?lise de regress?o polinomial. O teste de condutividade el?trica realizado no per?odo de oito horas mostra ser mais eficiente na separa??o de lotes de sementes de M. caesalpiniaefolia em diferentes n?veis de vigor comparativamente ao teste de lixivia??o de pot?ssio

Page generated in 0.4613 seconds