Consulta: subjectFacets:"Photoperiodism"
Registros recuperados: 5
Data/hora: 10/06/2024 09:11:06

High irradiance responses involving photoreversible multiple photoreceptors as related to photoperiodic induction of cell division in Euglena
Provedor de dados: 19
Autores: Bolige, Aoen; Goto, Ken.
Little is known about the photoreceptors involved in the photoperiodism of unicellular organisms, which we elucidated by deriving their action spectra. The flagellated alga Euglena gracilis exhibits photoperiodism, with a long-day response in cell reproduction. The underlying clock is a circadian rhythm with photoinductive capability, peaking at subjective dusk and occurring at the 26th hour in continuous darkness (DD) when transferred from continuous light (LL); it regulates photoinduction, a high-irradiance response (HIR), of a dark-capability of progressing through cell division. We derived the action spectra by irradiating E. gracilis with monochromatic light for 3 h at around the 26th hour; the action maxima occurred at 380, 450–460, 480, 610, 640,...
Palavras-chave: Cell division cycle; Complementary chromatic adaptation; Circadian; Euglena; End-of-day; Photoperiodism; Phytochrome; Shade avoidance.
Ano: 2007
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/719

Phytochrome-like responses in Euglena: a low fluence response that reorganizes the spectral dependence of the high irradiance response in long-day photoperiodic induction of cell division
Provedor de dados: 19
Autores: Bolige, Aoen; Goto, Ken.
Irradiance spectra change spatiotemporally, and angiosperms adapt accordingly, mainly through phytochromes. This study challenges the long-held belief that the flagellated alga Euglena gracilis lacks phytochromes and is therefore unaffected by spectral changes. We photoautotrophically cultured the alga under continuous light (LL), then transferred it to darkness. After about 26 h in darkness, different irradiations for 3 h enabled cell division in dark-arrested G2 cells evoking a high-irradiance response (HIR). The spectral characteristics of the irradiation during the LL period (pre-irradiation) defined the spectral sensitivity in the subsequent dark period. LL with light rich in the red spectrum led to a HIR to the red spectrum (R-HIR), whereas light...
Palavras-chave: Cell division; Circadian rhythms; End-of-day; Euglena; Photoperiodism; Phytochrome; Shade avoidance.
Ano: 2007
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/720

Estudo de desenvolvimento de Viguiera robusta Gardn., uma Asteraceae do cerrado
Provedor de dados: 88
Autores: Ruggiero,Patricia G. C.; Zaidan,Lilian B. P.
RESUMO - (Estudos de desenvolvimento de Viguiera robusta Gardn., uma Asteraceae do cerrado). Com o objetivo de se conhecer alguns aspectos da fisiologia de plantas do componente herbáceo da vegetação de cerrado, foram estudados aspectos do desenvolvimento de Viguiera robusta. As plantas, obtidas a partir de sementes (aquênios), foram mantidas sob condições fotoperiódicas controladas, acompanhando-se seu crescimento vegetativo e floração, no subseqüente período de crescimento. Os aquênios germinaram melhor sob luz constantes e às temperaturas de 30ºC e 20/30ºC permanecendo viáveis após 12 meses de armazenamento a 5ºC em frascos de vidro fechados. Sob fotoperíodo de 8 h houve menor crescimento vegetativo. A floração ocorre inicialmente nos fotoperíodos mais...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Flowering; Growth; Photoperiodism; Cerrado; Viguiera robusta.
Ano: 1997
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84041997000100001

Efeito do fotoperíodo no crescimento e no padrão de acúmulo de frutanos em plantas aclimatizadas de Gomphrena macrocephala St.-Hil. (Amaranthaceae)
Provedor de dados: 88
Autores: MOREIRA,MÍRIAM FERRAZ; VIEIRA,CANDIDA C. J.; ZAIDAN,LILIAN B. P.
Gomphrena macrocephala é uma espécie herbácea perene, nativa do cerrado brasileiro, que apresenta propriedades medicinais e potencial ornamental. Como outras espécies do cerrado, apresenta fases fenológicas bem definidas. A espécie tem sido estudada em função do acúmulo de carboidratos do tipo frutano em sua raiz tuberosa, cujo padrão de variação está relacionado com as fases fenológicas. O presente estudo utilizou plantas micropropagadas e aclimatizadas, com o objetivo de investigar a presença de frutanos em raízes tuberosas, além de verificar se as condições fotoperiódicas interferem no crescimento, no comportamento fenológico e no acúmulo de frutanos dessas plantas. Dias curtos (8 h) proporcionaram menor crescimento vegetativo, induziram o aparecimento...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Gomphrena; Photoperiodism; Fructan accumulation.
Ano: 1999
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84041999000300008

Influence of photoperiod and air temperature on the growth, flowering and maturation of soybean (Glycine max (L.) Merrill)
Provedor de dados: 63
Autores: Câmara,G.M.S.; Sediyama,T.; Dourado-Neto,D.; Bernardes,M.S.
With the purpose to evaluate the effect of short (12 hours) and long (13 and 14 hours) photoperiods and air temperature regimes (winter and summer growing seasons) on soybean behaviour, greenhouse experiments were installed at the Federal University of Viçosa, Brasil, from June 1984 to December 1985. In each experiment, under a completely randomized design with 12 treatments (soybean cultivars) and eight replicates: duration of vegetative period from emergency to stage R1 or flowering (DVP, in days); plant height (PH, m); number of nodes per plant at stage R1 (NNP); and duration of soybean cycle from emergency to stage R7 or physiological maturity point (DC, days), were evaluated. The results permit to conclude that: the vegetative period from emergency to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Phenology; Plant height; Photoperiodism.
Ano: 1997
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90161997000300017