Germination, carbohydrate composition and vigor of cryopreserved Caesalpinia echinata seeds

The present study investigated the germination and vigor of Caesalpinia echinata (Brazilwood) seeds stored at negative temperatures. Recently harvested seeds were cryopreserved at -18º or -196ºC and periodically evaluated for germination, seed vigor and carbohydrate composition. The temperatures did not influence the germination percentages or vigor. The germination percentage decreased from 88% in recently harvested seeds to 60% after 730 days of storage. The different temperature and storage times tested did not affect the vigor seed germination as indicated by the measures of plant growth and survival. The different temperatures used did not cause changes in the carbohydrate composition. The tegument cell walls were rich in lignin, arabinose and xylose. The cytoplasm of the cotyledons and embryos had high levels of glucose, fructose, and sucrose. The cryopreservation technique here presented was effective in the conservation of Brazilwood seeds for the medium term

Somatic embryogenesis in Pinus taeda L.

Com o objetivo de determinar um protocolo viável para a biotecnologia de embriogênese somática, analisando os fatores que afetam o processo e suas interações, e fornecer subsídios para sua utilização em processos de melhoramento florestal, foram estabelecidas culturas de embriões imaturos de 4 diferentes clones de Pinus taeda L., coletados em 7 diferentes épocas e utilizando-se 5 diferentes meios de cultura de tecidos, como meios de estabelecimento ou indução. Das espécies de Pinus conhecidas e utilizadas no setor florestal, Pinus taeda é considerada a espécie florestal, sob o aspecto econômico, mais importante do sul dos E.U.A. e a segunda mais importante no mundo. No Brasil, foi introduzida com grande sucesso. Devido a sua excelente adaptação na região sul, principalmente nos Estados do Paraná e Santa Catarina, é utilizada em programas de reflorestamento. O experimento foi conduzido no laboratório de cultura de tecidos da Escola de Recursos Florestais "Daniel B. Wamell", da Universidade da Georgia, em Athens, Estado da Georgia, E.U.A., sob supervisão do prof. Dr. Harry E Sommer e com a colaboração da Comissão Florestal da Georgia e do Serviço Florestal, do Departamento de Agricultura dos Estados Unidos. Os resultados obtidos permitem concluir que o protocolo para indução de embriogênese somática desenvolvido mostrou-se viável, resultando na indução de calos com características embriogênicas. A frequência de indução de calos foi da ordem de 36,6%. Foram também demonstrados efeitos de 3 fatores (clone, meio de cultura e época de coleta) e da interação entre eles sobre a percentagem de indução, indicando que genótipo, ambiente físico e estádio de desenvolvimento afetam a regeneração in vitro. As técnicas de embriogênese somática podem resultar, se bem adequadas, manejadas e incrementadas, em taxas de indução maiores, sendo uma ferramenta auxiliar nos processos de melhoramento florestal.In·order to determine a viable protocol for the biotechnology of somatic embryogenesis, analysing the factors which affect the process and their interactions, and provide subsidies for its use in processes of forest improvement, immature embryos cultures were established from 4 different clones of loblolly pine (Pinus taeda L.), collected in 7 different dates and using 5 different tissue culture media as establishment or induction media. From all the pine species known and used in forestry, loblolly pine is considered, under economical aspects, the most important forest tree in the south of the United States and the second most important in the world. It was successfully introduced in Brazil due to its excellent adaptation in the south, in particular the States of Paraná and Santa Catarina, being used in reforestation programms. The experiment was carried out in the tissue culture laboratory, of the Daniel B. Wamell School of Forest Resources, of The University of Georgia, in Athens, State of Georgia, U.S.A., under supervision of prof. Dr. Harry E. Sommer, and with the collaboration of the Georgia Forestry Comission and the U.S.D.A. Forest Service. The results obtained allow us to conclude that the protocol developed for the induction of somatic embryogenesis was viable, having as result the induction of calli with embryogenic characteristics. The frequency of induction was around 36.6%. The techniques of somatic embryogenesis can result, if well adjusted, managed and improved, in higher induction rates, being a helpful tool for the process of tree improvement

Somatic embryogenesis in Pinus taeda L.

Com o objetivo de determinar um protocolo viável para a biotecnologia de embriogênese somática, analisando os fatores que afetam o processo e suas interações, e fornecer subsídios para sua utilização em processos de melhoramento florestal, foram estabelecidas culturas de embriões imaturos de 4 diferentes clones de Pinus taeda L., coletados em 7 diferentes épocas e utilizando-se 5 diferentes meios de cultura de tecidos, como meios de estabelecimento ou indução. Das espécies de Pinus conhecidas e utilizadas no setor florestal, Pinus taeda é considerada a espécie florestal, sob o aspecto econômico, mais importante do sul dos E.U.A. e a segunda mais importante no mundo. No Brasil, foi introduzida com grande sucesso. Devido a sua excelente adaptação na região sul, principalmente nos Estados do Paraná e Santa Catarina, é utilizada em programas de reflorestamento. O experimento foi conduzido no laboratório de cultura de tecidos da Escola de Recursos Florestais "Daniel B. Wamell", da Universidade da Georgia, em Athens, Estado da Georgia, E.U.A., sob supervisão do prof. Dr. Harry E Sommer e com a colaboração da Comissão Florestal da Georgia e do Serviço Florestal, do Departamento de Agricultura dos Estados Unidos. Os resultados obtidos permitem concluir que o protocolo para indução de embriogênese somática desenvolvido mostrou-se viável, resultando na indução de calos com características embriogênicas. A frequência de indução de calos foi da ordem de 36,6%. Foram também demonstrados efeitos de 3 fatores (clone, meio de cultura e época de coleta) e da interação entre eles sobre a percentagem de indução, indicando que genótipo, ambiente físico e estádio de desenvolvimento afetam a regeneração in vitro. As técnicas de embriogênese somática podem resultar, se bem adequadas, manejadas e incrementadas, em taxas de indução maiores, sendo uma ferramenta auxiliar nos processos de melhoramento florestal.In·order to determine a viable protocol for the biotechnology of somatic embryogenesis, analysing the factors which affect the process and their interactions, and provide subsidies for its use in processes of forest improvement, immature embryos cultures were established from 4 different clones of loblolly pine (Pinus taeda L.), collected in 7 different dates and using 5 different tissue culture media as establishment or induction media. From all the pine species known and used in forestry, loblolly pine is considered, under economical aspects, the most important forest tree in the south of the United States and the second most important in the world. It was successfully introduced in Brazil due to its excellent adaptation in the south, in particular the States of Paraná and Santa Catarina, being used in reforestation programms. The experiment was carried out in the tissue culture laboratory, of the Daniel B. Wamell School of Forest Resources, of The University of Georgia, in Athens, State of Georgia, U.S.A., under supervision of prof. Dr. Harry E. Sommer, and with the collaboration of the Georgia Forestry Comission and the U.S.D.A. Forest Service. The results obtained allow us to conclude that the protocol developed for the induction of somatic embryogenesis was viable, having as result the induction of calli with embryogenic characteristics. The frequency of induction was around 36.6%. The techniques of somatic embryogenesis can result, if well adjusted, managed and improved, in higher induction rates, being a helpful tool for the process of tree improvement

Innovation in Propagation and Cultivation of Ornamental Plants

Ornamental plants are constantly being improved by new technologies and cultivation systems to provide new, high-quality plant material for one of the most demanding markets in the horticulture sector [...

In vitro germination and seedling development of cryopreserved Dendrobium hybrid mature seeds

In vitro germination and seedling development from Dendrobium Swartz. hybrid ‘Sena Red’, ‘Mini WRL’, ‘Jaquelyn Thomas’, and ‘BFC Pink’ seeds cryopreserved through vitrification (PVS2) were evaluated. Germination percentages after cryopreservation (LN) were variable among different controls and treatments, despite the initial high seed viability for all hybrids. Seeds exposed to PVS2 at ice temperature from 1 to 3 h prior to LN exhibited significantly higher germination than seeds exposed to PVS2 at room temperature for the same time periods. No significant differences in germination percentages were observed for time exposure to PVS2 at 1, 2 or 3 h for ‘Sena Red’, ‘Mini WRL’, and ‘BFC Pink’. Seeds of ‘Jaquelyn Thomas’ exposed to 1 h prior to LN showed higher germination percentage than for exposure to 2 or 3 h. The combination of a pre-cooling treatment (ice) with a dehydration treatment (PVS2) for a period of time of 1–3 h was essential to allow proper germination of cryopreserved seeds. Although variability in seed germination among different hybrids and treatments was observed, germination was above 50% of the controls and all germinated seeds developed into normal seedlings with healthy shoot and root formation. No abnormalities, nutritional deficiencies, or diseases were observed in developed seedlings and no significant differences were observed for seedling growth and development from germinated seeds among the different hybrids. Seedlings transplanted to pots acclimatized well and developed into normal plants within 6–8 months in greenhouse. Transplanted seedlings exhibited 100% survival for all hybrids

Cryopreservation, early seedling development, and genetic stability of Oncidium flexuosum Sims

An efficient cryopreservation protocol was developed for mature seeds of Oncidium flexuosum Sims. Seed morphology, protocorm formation, and early seedling development were also assessed. The effects of phloroglucinol and Supercool X-1000® as cryoprotectant additives in the vitrification solution were investigated. Dehydration using the plant vitrification solution 2 (PVS2) for 60 and 120 min prior to immersion in liquid nitrogen promoted the highest frequency of in vitro seed germination 6 weeks following culture on half-strength Murashige and Skoog (1/2 MS) medium. Mature seeds submitted to vitrification for 120 min in PVS2 and 1 % phloroglucinol at 0 °C enhanced germination by 68 %, whereas in PVS2 and 1 % Supercool X-1000® germination was just moderately enhanced (26 %). In vitro-germinating seedlings developed healthy shoots and roots without the use of plant growth regulators. After 6 months of growth, there were no differences between in vitro- and ex vitro-grown seedlings for various phenotypic characteristics, including shoot length, number of leaves, number and length of roots, and fresh and dry weight. Seedlings were transferred to greenhouse conditions and successfully acclimatized, further developing into normal plants with over 90 % survival. Comparative analysis of seedlings from control and vitrified seeds using flow cytometry indicated that no change in ploidy levels occurred as a result of cryopreservation, therefore maintaining seedlings genetic stability. In this study, vitrification with PVS2 for 120 min with the addition of 1 % phloroglucinol offers a simple, safe, and feasible protocol for cryopreservation of O. flexuosum mature seeds. © 2013 Springer Science+Business Media Dordrecht

Germination, Carbohydrate Composition and Vigor of Cryopreserved Caesalpinia echinata Seeds

The present study investigated the germination and vigor of Caesalpinia echinata (Brazilwood) seeds stored at negative temperatures. Recently harvested seeds were cryopreserved at -18 degrees or -196 degrees C and periodically evaluated for germination, seed vigor and carbohydrate composition. The temperatures did not influence the germination percentages or vigor. The germination percentage decreased from 88% in recently harvested seeds to 60% after 730 days of storage. The different temperature and storage times tested did not affect the vigor seed germination as indicated by the measures of plant growth and survival. The different temperatures used did not cause changes in the carbohydrate composition. The tegument cell walls were rich in lignin, arabinose and xylose. The cytoplasm of the cotyledons and embryos had high levels of glucose, fructose, and sucrose. The cryopreservation technique here presented was effective in the conservation of Brazilwood seeds for the medium term.Fundacao BiodiversitasFundacao BiodiversitasFundo de Apoio a Ciencia e Tecnologia da Prefeitura Municipal de Vitoria (FACITEC)Fundo de Apoio a Ciencia e Tecnologia da Prefeitura Municipal de Vitoria (FACITEC)e Fundacao de Apoio a Ciencia e Tecnologia do Espirito Santo (FAPES)e Fundacao de Apoio a Ciencia e Tecnologia do Espirito Santo (FAPES)PetrobrasPETROBRA

Meios de cultura, reguladores de crescimento e fontes de nitrogênio na regulação da calogênese do pau-brasil (Caesalpinia echinata Lam.) Culture media, growth regulators and nitrogen sources in callus formation regulation of Brazilwood (Caesalpinia echinata Lam.)

A regulação da calogênese é o primeiro passo para a embriogênese somática indireta in vitro. Nesse sentido, foram investigados os efeitos de diferentes meios de cultura, reguladores de crescimento e fontes nitrogenadas no desenvolvimento de calos em tecidos foliares de Caesalpinia echinata (pau-brasil). Explantes foliares foram cultivados em meios de cultura MS, B5, White e WPM. Testou-se, também, o efeito dos compostos nitrogenados (NH4NO3, KNO3 e glutamina) e a interação entre auxinas (2,4-D, AIA e AIB) e citocininas (BAP e KIN) na desdiferenciação celular indicado pela formação de calos. Os meios MS, B5 e White não foram significantemente diferentes e proporcionaram melhores resultados. Em meio MS contendo as fontes nitrogenadas 2,4 g L-1 NH4NO3 e 1,35 g L-1 glutamina + 4,11 g L-1 de KNO3 na presença de 1,0 mg L-1 2,4-D e 5,0 mg L-1 BAP ocorreu maior proliferação celular indicada pela massa fresca dos calos. As combinações dos reguladores 0,5 mg L-1 2,4-D + 5 mg L-1 BAP e 0,5 mg L-1 AIB + 5,0 mg L-1 BAP suplementado com 2,4 g L-1 NH4NO3 em meio MS estimularam o crescimento dos calos. De maneira geral, os calos apresentaram aspectos friáveis, não embriogênicos, com acúmulo de fenóis e presença de áreas meristemáticas (meristemóides).<br>The regulation of callus formation is the first step to indirect somatic embryogenesis in vitro. Therefore, we investigated hormonal and nutrient factors on development of callus in leaf tissues of Caesalpinia echinata (Brazilwood). Explants were cultivated in culture media MS, B5, WPM, and White. The effect of nitrogen sources (NH4NO3, KNO3 and glutamine) and the interaction between auxins (2,4-D, IAA and IBA) and cytokinins (BAP and KIN) were also evaluated. Media MS, B5 and White were not significantly different and provided better results. MS medium containing 2.4 g L-1 NH4NO3, 1.35 g L-1 glutamine, and 4.11 g L-1 of KNO3 in the presence of 1 mg.L-1 2,4-D and 5 mg.L-1 BAP increased cellular proliferation as determined by fresh weight of callus. The combination of plant growth regulators at 0.5 mg L-1 2,4-D + 5.0 mg L-1 BAP and 0.5 mg L-1 IBA + 5.0 mg L-1 BAP supplemented with 2.4 g L-1 NH4NO3 in MS medium stimulated growth of callus. In general, callus showed friable, non-embryogenic characteristics, with accumulation of phenolics and the presence of meristematic areas (meristems)