Data/hora: 10/06/2024 06:43:14

Provedor de dados: | 69
País: | Chile
Título: | Growth responses of Betula pendula ecotypes to red and far-red light
Autores: | Tsegay,Berhanu A.; Lund,Leidulf; Nilsen,Jarle; Olsen,Jorunn E.; Molmann,Jorgen M.; Ernsten,Arild; Juntttila,Olavi.
Data: | 2005-04-01
Ano: | 2005
Palavras-chave: | Diode; Ecotype; Monochromatic; Photomorphogenesis; Phytochrome; Photosynthetically active radiation; PAR.
Resumo: | The effect of Red light (R), Far-red light (FR) and R/FR combinations on shoot growth of latitudinal ecotypes of B. pendula was studied using special diodes that emit monochromatic lights. When a 12 hrs PAR (110 &amp;micro;mol m-2 s-1) was extended with R, FR or R/FR ratios, lower intensities of monochromatic lights could not prevent growth cessation. At 25 &amp;micro;mol m-2 s-1, FR compared to R enhanced stem elongation in all ecotypes. This was due to the inhibitive effect of R on internode elongation. When day-length was extended by R/FR at various ratios, there was continuous shoot elongation, but was found to be declining with increasing ratios. The more the R, the shorter were the internodes of each plant. B. pendula ecotypes produced branches when PAR light during the day was extended by incandescent light, but did not do so when the light extensions were made by monochromatic R or FR or their combination. Branching increased with decreasing latitude of the ecotype
Tipo: | Journal article
Idioma: | Inglês
Identificador: | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000100005
Editor: | Pontificia Universidad Católica de Valparaíso
Formato: | text/html
Fonte: | Electronic Journal of Biotechnology  v.8 n.1 2005