Sensitivity of brazilian-pine (Araucária angustifolia) embryos to desiccation and temperature
Autor(a) principal: | |
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Data de Publicação: | 2004 |
Outros Autores: | , |
Tipo de documento: | Artigo |
Idioma: | por |
Título da fonte: | Pesquisa Florestal Brasileira (Online) |
Texto Completo: | https://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/1603 |
Resumo: | The “recalcitrant” behavior of Araucaria angustifolia (Bert.) O. Kuntze seeds (Brazilian pine) limits the conservation of genetic resources of this important species in ex situ genebanks. As initial steps in developing storage protocols, we studied the interaction of water content and temperature on embryo survival. Embryos were excised from seeds and “flash-dried” to water contents as low as 0.29 g water/g dry mass and then exposed to 0°C, -5°C and -18°C for 4 h. Drying rate was calculated from drying time courses and expressed as (g water / g dry weight) / hour. Other authors have studied the effects of desiccation of whole seed of A. angustifolia on viability. In order to compare moisture content of whole seeds to that of embryonic axes, seeds of A. angustifolia were placed on the bench (25°C and 25%RH) and left to dry. Fresh weight of intact seeds and embryos excised from these seeds were also measured. Water contents were calculated and expressed on dry weight basis as g water / g dw. Increasing drying rate improved survival at lower water contents. Further, survival of embryos dried up to 0.29 g/ g and exposure to 25°C (25% survival) and 0°C (37.5% survival) suggests that cryopreservation using ultra-rapid cooling techniques may provide a method for long-term conservation of this important species. We suggest new studies towards technical approaches. |
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Sensitivity of brazilian-pine (Araucária angustifolia) embryos to desiccation and temperatureSensibilidade de embriões do pinheiro-brasileiro (Araucaria angustifolia) à desidratação e baixa temperaturaSeedsGermplasmBrazilian pineDesiccationGenetic conservationSementesGermoplasmaSecagemConservaçãoThe “recalcitrant” behavior of Araucaria angustifolia (Bert.) O. Kuntze seeds (Brazilian pine) limits the conservation of genetic resources of this important species in ex situ genebanks. As initial steps in developing storage protocols, we studied the interaction of water content and temperature on embryo survival. Embryos were excised from seeds and “flash-dried” to water contents as low as 0.29 g water/g dry mass and then exposed to 0°C, -5°C and -18°C for 4 h. Drying rate was calculated from drying time courses and expressed as (g water / g dry weight) / hour. Other authors have studied the effects of desiccation of whole seed of A. angustifolia on viability. In order to compare moisture content of whole seeds to that of embryonic axes, seeds of A. angustifolia were placed on the bench (25°C and 25%RH) and left to dry. Fresh weight of intact seeds and embryos excised from these seeds were also measured. Water contents were calculated and expressed on dry weight basis as g water / g dw. Increasing drying rate improved survival at lower water contents. Further, survival of embryos dried up to 0.29 g/ g and exposure to 25°C (25% survival) and 0°C (37.5% survival) suggests that cryopreservation using ultra-rapid cooling techniques may provide a method for long-term conservation of this important species. We suggest new studies towards technical approaches.O comportamento “recalcitrante” das sementes de Araucaria angustifolia (Bertoloni.) Otto Kuntze (pinheiro-brasileiro) limita a conservação ex-situ dos recursos genéticos dessa importante espécie, em bancos de sementes. A interação entre o conteúdo de água e temperatura sobre a sobrevivência do embrião foi estudada como ponto de partida para o desenvolvimento de um protocolo para o armazenamento dessa espécie. O objetivo principal deste estudo foi verificar se embriões de Araucaria angustifolia sobreviveriam à secagem ultra-rápida, utilizando o método “flash-drying”, e adicionalmente, expondo os embriões à baixas temperaturas. Os embriões foram extraídos das sementes e submetidos à secagem ultra-rápida a teores de 0,29 g de água/g de matéria seca, e em seguida expostos a 0°C, -5°C e –18°C por 4 horas. A taxa de secagem foi calculada à partir do processo de secagem e expressa em (g de água / g matéria seca)/ hora. Outros autores vêm estudando os efeitos da dessecação na viabilidade em sementes inteiras. Para que fosse possível comparar o teor de água de sementes inteiras, adotado por outro autor, com o de embriões, sementes de A. angustifolia foram expostas a 25°C e 25 %UR e deixadas a secar. Foram obtidos o peso fresco de sementes inteiras e de seus embriões, também expressos em g de água / g matéria seca. O aumento na rapidez de desidratação melhorou a taxa de sobreviência dos embriões a 25°C e 0°C. A sobrevivência de embriões desidratados a 0,29 g/g e expostos a 25°C (25,0% de sobrevivência) e 0°C (37,5% de sobrevivência), sugere que a criopreservação de embriões após terem sido submetidos à secagem ultra-rápida do método “flash-drying” e utilizando-se técnicas de congelamento ultra-rápido, talvez seja um método de conservação a longo prazo para essa importante espécie e abre uma promissora linha de pesquisa permitindo a eventual conservação a médio e longo prazo de sementes de outras espécies classificadas como recalcitrantes. Sugere-se novos estudos para aprimorar a técnica e o desenvolvimento de protocolo para o desenvolvimento de embriões de A. angustifolia que sobreviverem.Embrapa Florestas2004-06-30info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionapplication/pdfhttps://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/1603Pesquisa Florestal Brasileira; n. 48 (2004): jan./jun.; 129-137Pesquisa Florestal Brasileira; No. 48 (2004): jan./jun.; 129-1371983-26051809-3647reponame:Pesquisa Florestal Brasileira (Online)instname:Empresa Brasileira de Pesquisa Agropecuária (Embrapa)instacron:EMBRAPAporhttps://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/1603/656Medeiros, Antonio Carlos de SouzaWalters, CristinaHill, Lisainfo:eu-repo/semantics/openAccess2018-03-22T17:55:25Zoai:pfb.cnpf.embrapa.br/pfb:article/1603Revistahttps://pfb.cnpf.embrapa.br/pfb/index.php/pfb/PUBhttps://pfb.cnpf.embrapa.br/pfb/index.php/pfb/oaipfb@embrapa.br || revista.pfb@gmail.com || patricia.mattos@embrapa.br1983-26051809-3647opendoar:2018-03-22T17:55:25Pesquisa Florestal Brasileira (Online) - Empresa Brasileira de Pesquisa Agropecuária (Embrapa)false |
dc.title.none.fl_str_mv |
Sensitivity of brazilian-pine (Araucária angustifolia) embryos to desiccation and temperature Sensibilidade de embriões do pinheiro-brasileiro (Araucaria angustifolia) à desidratação e baixa temperatura |
title |
Sensitivity of brazilian-pine (Araucária angustifolia) embryos to desiccation and temperature |
spellingShingle |
Sensitivity of brazilian-pine (Araucária angustifolia) embryos to desiccation and temperature Medeiros, Antonio Carlos de Souza Seeds Germplasm Brazilian pine Desiccation Genetic conservation Sementes Germoplasma Secagem Conservação |
title_short |
Sensitivity of brazilian-pine (Araucária angustifolia) embryos to desiccation and temperature |
title_full |
Sensitivity of brazilian-pine (Araucária angustifolia) embryos to desiccation and temperature |
title_fullStr |
Sensitivity of brazilian-pine (Araucária angustifolia) embryos to desiccation and temperature |
title_full_unstemmed |
Sensitivity of brazilian-pine (Araucária angustifolia) embryos to desiccation and temperature |
title_sort |
Sensitivity of brazilian-pine (Araucária angustifolia) embryos to desiccation and temperature |
author |
Medeiros, Antonio Carlos de Souza |
author_facet |
Medeiros, Antonio Carlos de Souza Walters, Cristina Hill, Lisa |
author_role |
author |
author2 |
Walters, Cristina Hill, Lisa |
author2_role |
author author |
dc.contributor.author.fl_str_mv |
Medeiros, Antonio Carlos de Souza Walters, Cristina Hill, Lisa |
dc.subject.por.fl_str_mv |
Seeds Germplasm Brazilian pine Desiccation Genetic conservation Sementes Germoplasma Secagem Conservação |
topic |
Seeds Germplasm Brazilian pine Desiccation Genetic conservation Sementes Germoplasma Secagem Conservação |
description |
The “recalcitrant” behavior of Araucaria angustifolia (Bert.) O. Kuntze seeds (Brazilian pine) limits the conservation of genetic resources of this important species in ex situ genebanks. As initial steps in developing storage protocols, we studied the interaction of water content and temperature on embryo survival. Embryos were excised from seeds and “flash-dried” to water contents as low as 0.29 g water/g dry mass and then exposed to 0°C, -5°C and -18°C for 4 h. Drying rate was calculated from drying time courses and expressed as (g water / g dry weight) / hour. Other authors have studied the effects of desiccation of whole seed of A. angustifolia on viability. In order to compare moisture content of whole seeds to that of embryonic axes, seeds of A. angustifolia were placed on the bench (25°C and 25%RH) and left to dry. Fresh weight of intact seeds and embryos excised from these seeds were also measured. Water contents were calculated and expressed on dry weight basis as g water / g dw. Increasing drying rate improved survival at lower water contents. Further, survival of embryos dried up to 0.29 g/ g and exposure to 25°C (25% survival) and 0°C (37.5% survival) suggests that cryopreservation using ultra-rapid cooling techniques may provide a method for long-term conservation of this important species. We suggest new studies towards technical approaches. |
publishDate |
2004 |
dc.date.none.fl_str_mv |
2004-06-30 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
https://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/1603 |
url |
https://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/1603 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.relation.none.fl_str_mv |
https://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/1603/656 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Embrapa Florestas |
publisher.none.fl_str_mv |
Embrapa Florestas |
dc.source.none.fl_str_mv |
Pesquisa Florestal Brasileira; n. 48 (2004): jan./jun.; 129-137 Pesquisa Florestal Brasileira; No. 48 (2004): jan./jun.; 129-137 1983-2605 1809-3647 reponame:Pesquisa Florestal Brasileira (Online) instname:Empresa Brasileira de Pesquisa Agropecuária (Embrapa) instacron:EMBRAPA |
instname_str |
Empresa Brasileira de Pesquisa Agropecuária (Embrapa) |
instacron_str |
EMBRAPA |
institution |
EMBRAPA |
reponame_str |
Pesquisa Florestal Brasileira (Online) |
collection |
Pesquisa Florestal Brasileira (Online) |
repository.name.fl_str_mv |
Pesquisa Florestal Brasileira (Online) - Empresa Brasileira de Pesquisa Agropecuária (Embrapa) |
repository.mail.fl_str_mv |
pfb@embrapa.br || revista.pfb@gmail.com || patricia.mattos@embrapa.br |
_version_ |
1783370936700895232 |