BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Green light effects on plant growth and development - Professor Ke
 vin Folta\, University of Florida
DTSTART:20071004T150000Z
DTEND:20071004T160000Z
UID:TALK8074@talks.cam.ac.uk
CONTACT:3901
DESCRIPTION:In the developing seedling light quality\, quantity\, and dura
 tion strongly influence establishment. A rich history of reports clearly s
 how that red\, blue and far-red light have specific effects that control t
 he processes in this developmental transition. During acclimation to the l
 ight environment\, light drives many morphological and molecular-genetic p
 rocesses\, such as inhibition of hypocotyl elongation and increase in plas
 tid transcripts encoding proteins required for photosynthesis. Our laborat
 ory has demonstrated specific effects of narrow-bandwidth green light that
  oppose these processes\, independently of known sensory systems. Addition
 ally\, we have expanded on recent evidence that indicates a role for green
  light in directly reversing cryptochrome-mediated responses. Our findings
  support a hypothesis that green light signals integrate and balance the d
 evelopmental effects induced by red and/or blue light acting through the p
 hytochrome and cryptochrome systems. Co-irradiation with red\, blue and gr
 een light using our specialized LED chambers indicates that green light ca
 n conditionally reverse stem elongation and anthocyanin driven by blue and
 /or red light. This effect is cryptochrome dependent. Supplemental green l
 ight induces changes in plant architecture reminiscent of shaded growth ha
 bits. When dark-grown seedlings were treated with a short\, single pulse o
 f red light\, a pulse of dim green light (1/500th the fluence\, approximat
 ely "safelight" fluence rates)\, or a combination of both treatments\, the
  minor green treatment can negate red-induced transcript accumulation. The
  effects of green are apparent only during specific windows in seedling de
 velopment. Together\, these data support a hypothesis that a green light s
 ensing system works carefully in concert with known sensory systems to opt
 imize seedling morphology and physiology during establishment\, and are mo
 st relevant in low light environments.\nhttp://www.arabidopsisthaliana.com
 /
LOCATION:Department of Plant Sciences\, Large Lecture Theatre
END:VEVENT
END:VCALENDAR