Uncoupling light quality from light irradiance effects in Helianthus annuus shoots: putative roles for plant hormones in leaf and internode growth.

@article{Kurepin2007UncouplingLQ,
  title={Uncoupling light quality from light irradiance effects in Helianthus annuus shoots: putative roles for plant hormones in leaf and internode growth.},
  author={Leonid V. Kurepin and R J Neil Emery and Richard Persons Pharis and David M. Reid},
  journal={Journal of experimental botany},
  year={2007},
  volume={58 8},
  pages={2145-57}
}
An attempt has been made to uncouple the effects of the two primary components of shade light, a reduced red to far-red (R/FR) ratio and low photosynthetically active radiation (PAR), on the elongation of the youngest internode of sunflower (Helianthus annuus) seedlings. Maximal internode growth (length and biomass) was induced by a shade light having a reduced R/FR ratio (0.85) under the low PAR of 157 micromol m(-2) s(-1). Reducing the R/FR ratio under normal PAR (421 micromol m(-2) s(-1… CONTINUE READING