|
|
|
Registros recuperados: 71 | |
|
| |
|
|
WANG,Y.H.; MA,Y.L.; FENG,G.J.; LI,H.H.. |
ABSTRACT: Large crabgrass is one of the worst exotic weed in tropical, subtropical, and temperate regions of the world. In this study, the abiotic factors affecting seed germination and early seedling emergence of large crabgrass were investigated under laboratory conditions. The optimum temperatures of germination occurred at the range from 25 to 35 oC under 12 h light/12 h dark condition. Some seeds could germinate in the dark, but light exposure significantly stimulated the germination. Large crabgrass seed was tolerant to salinity level range of 0 to 160 and low water potential (11% germination at -0.8 MPa). Medium pH had no significant effect on seed germination and more than 90% seeds germination was obtained over a broad pH range from 4.0 to 10.0.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Temperature; Light; Osmotic potential; Heat-shock; Burial depth. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100268 |
| |
|
|
Tavares,BO; Pereira,DF; Bueno,LGF; Silva,GF. |
ABSTRACT Light is an important factor in the management of laying poultry. The ideal lamp spectrum that provides the best welfare conditions still needs to be determined. Wavelength and light intensity influence poultry behavior and their welfare. This study evaluated the influence of four lamps types with different light spectra on the behavior of seventy 52-week laying hens. Incandescent, fluorescent, and sodium and mercury vapor lamps were set in a different poultry house each and supplied similar light intensities. Layer behavior was video-recorded three times weekly using video cameras installed on the ceiling. The effects of different wavelengths emitted by the light sources on layer behavior were evaluated by the Kruskal-Wallis median test. Results... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Animal behavior; Light; Animal precision. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2015000400511 |
| |
|
| |
|
|
FELFILI,JEANINE MARIA; HILGBERT,LUÍS FERNANDO; FRANCO,AUGUSTO CÉSAR; SOUSA-SILVA,JOSÉ CARLOS; RESENDE,ALBA VALÉRIA; NOGUEIRA,MARIA VALDENETE PEREIRA. |
As perturbações por desmatamentos, queimadas e mineração nas matas de galeria estão se avolumando em função do desenvolvimento econômico, gerando desequilíbrio ecológico e tornando necessários estudos que possibilitem a recuperação deste ecossistema. O objetivo deste trabalho foi o de avaliar, em viveiro, a resposta da espécie Sclerolobium paniculatum submetida a quatro níveis de sombreamento. O delineamento experimental foi inteiramente casualizado, com quatro tratamentos e quinze repetições. Cada tratamento representou uma fase da sucessão em floresta natural: pleno sol, simulando uma condição de área degradada; condição de clareira, com aproximadamente 50% de sombreamento; dossel da mata, em fase de fechamento, com sombreamento médio de 70%; dossel... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Gallery forests; Light; Shading; Brazil. |
Ano: 1999 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84041999000500011 |
| |
|
| |
|
|
Gama,Andréa M. da S; Calazans,Danilo; Fontoura,Nelson F. |
Metamysidopsis atlantica elongata (Bascescu, 1968) is a common mysid in the surf zone of sandy beaches from the state of Rio Grande do Sul, Brazil, where it is frequently recorded forming dense aggregations. Trough laboratory trials, behavioral responses to salinity (10, 20, 25, 28, 30, 40 e 45), temperature (10, 15, 20, 30±1ºC) and light (yes/no) were tested using adult males, adult females and juveniles. Although there was no response to temperature, the species showed clear response to salinity and light. In the presence of light, organisms remained in the bottom of the aquaria, but moved to surface when bottom salinities were increased. In the absence of light, adults moved to the surface. However, juveniles moved down to or remained on the bottom,... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mysids; Behavior; Light; Predation. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212011000100014 |
| |
|
| |
|
|
Mendonça,Giovana Soares de; Martins,Cibele Chalita; Martins,Dagoberto; Costa,Neumárcio Vilanova da. |
The invasive behaviour of sourgrass (Digitaria insularis) in cultivated areas is due to its strategy of aggressive regeneration, which is based on seed germination. Knowledge of the physiological ecology of this species can contribute to the development of management and control strategies. The aim of this research was to understand the effects of provenance, temperature and light on the germination of sourgrass seeds collected in the Brazilian state of São Paulo in the cities of Americana, Botucatu and São José do Rio Preto and in the state of Paraná in the city of São Miguel do Iguaçu. The seeds were left to germinate at temperatures of 15, 25, 35 and 45 °C, both with and without light. The number of normal seedlings was recorded daily from seven to 60... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Sourgrass; Plant physiology; Provenance; Light; Temperature. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902014000400021 |
| |
|
|
Jacob,FG; Salgado,DA; Nää,IA; Baracho,MS. |
ABSTRACT The present study had the objective of analysing the impact of the use of environmental enrichment (music and light stimuli), broiler sex, and age in broiler chickens’ weight during growth. The observational study was carried out on a commercial farm. The environmental enrichment consisted of broilers’ stimulation by sound and light, and a house was kept without stimulus (control). The music stimuli consisted of different music styles and was played during the experiment to promote motivation for the birds. The light stimuli came from a coloured (red and green) LED strobe projector. Both stimuli were applied once a day for about 6 minutes, for five weeks. The broilers were weighed at the end of each week of growth. Throughout the growth period,... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Broiler production broiler welfare; Music; Light. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2020000200303 |
| |
|
|
Simão,Edson; Takaki,Massanori. |
The effect of light and temperature on Tibouchina mutabilis seed germination was analyzed by isothermic incubations in the range of 10 to 40 °C, with 5 °C intervals under both continuous white light (32.85 µmolm-2s-1) and darkness and alternating temperatures (15-20; 15-25; 15-30; 15-35; 20-25; 20-30; 20-35; 25-30; 25-35 and 30-35 °C) under both photoperiod of 12 hours and continuous darkness. The seeds of T. mutabilis need light to trigger the germination and no germination was observed in darkness. The range of optimum temperatures for germination was between 25 to 30 °C and the 20-25 °C alternating temperatures. These results indicate that T. mutabilis behaves as a pioneer species and daily alternating temperatures did not change the light sensitivity... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Light; Phytochrome; Seed germination; Tibouchina. |
Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032008000200006 |
| |
|
| |
|
|
Rezvani,Mohammad; Zaefarian,Faezeh; Amini,Vajihe. |
Shepherd's purse (Capsella bursa-pastoris) is a problematic weed in citrus orchards and crop fields in northern Iran. In a series of laboratory and greenhouse experiments, we evaluated the effects that treatment with gibberellic acid (GA3) and potassium nitrate (KNO3), as well as environmental factors, including temperature, the duration of pre-chilling (wet and dry), drought stress, salt stress, pH, and sowing depth, have on seed dormancy breaking and germination in C. bursa-pastoris. Treatment with GA3 strongly stimulated germination of C. bursa-pastoris in conditions of light/dark and continuous darkness. The germination rate was highest (40.08%) for seeds treated with 400 ppm of GA3 in the light/dark condition. Treatment with KNO3 did not significantly... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Drought and salt stress; Gibberellic acid; Light; Temperature; Sowing depth. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062014000400002 |
| |
|
|
XIONG,RC.; MA,Y.; WU,HW.; JIANG,WL.; MA,XY.. |
ABSTRACT: Velvetleaf, an annual broadleaf weed, is a common and troublesome weed of cropping systems worldwide. Laboratory and field experiments were conducted to determine the effects of environmental factors on germination and emergence of velvetleaf. Seeds germinated over a range of constant temperatures from 10 to 40 oC regardless of light conditions, but no germination occurred at temperature below 5 oC and beyond 50 oC. Seeds germinated at alternating temperature regimes of 15/5 to 40/30 oC, with maximum germination (>90%) at alternating temperatures of 40/30 oC. Germination was sensitive to water stress, and only 0.4% of the seeds germinated at the osmotic potential of -0.4 MPa. There was no germination at ? 0.6 MPa. Moreover, germination was... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Burial depth; Light; Osmotic potential; Saline and alkaline stress; Temperature. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100321 |
| |
|
| |
|
| |
|
| |
|
|
Cognat, Mathis; Ganthy, Florian; Auby, Isabelle; Barraquand, Frederic; Rigouin, Loic; Sottolichio, Aldo. |
The relative impact of light, depth, hydrology, hydrodynamics, sediment and nutrients on growth of the seagrass Zostera noltei was investigated in Arcachon Bay, where the extent of seagrass beds has been decreasing for 20 years. A comprehensive multi-parameter survey of 9 sites was conducted monthly over one year. A three-parameter logistic growth model was fitted to biomass data to unravel the relative contributions of environmental factors on seagrass growth. The present study highlights the fact that, in addition to the dominant positive effect of light on plant growth, the hydrological and hydrodynamic parameters were important drivers for Z. noltei growth at the scale of the whole Bay. At the scale of individual sites, other factors such as macroalgal... |
Tipo: Text |
Palavras-chave: Physical parameters; Light; Hydrodynamics; Adaptation; Statistical growth model. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00451/56229/57789.pdf |
| |
|
| |
|
| |
Registros recuperados: 71 | |
|
|
|