Very high levels of sunlight can be hazardous to plants, overwhelming their ability to photosynthesise. This effect is exaggerated when there is a shortage of water or extreme temperatures. The resulting damage to the delicate photosynthetic membranes in the plant leads to impaired growth, cell destruction and, eventually, plant death. The scientists, funded by the Biotechnology and Biological Sciences Research Council (BBSRC), have found that plants are able to turn unwanted absorbed light into heat by altering the structure of one of the proteins in these membranes. This unique nanoscale safety valve prevents plant damage by harmlessly dissipating the lethal excess radiation. This photoprotective process was found to be aided by a special carotenoid molecule called zeaxanthin and plants with higher levels of this molecule appear to be better protected.
Professor Peter Horton, research leader at the University of Sheffield, said, "Plants use a range of processes to adapt to harsh and potentially damaging environmental conditions. We are beginning to understand the mechanisms plants have at a molecular level to prevent damage from excess sunlight. We hope that this knowledge could be used to improve photosynthesis rates, and therefore productivity, in staple crops that feed millions in parts of the world where environmental conditions can be particularly harsh."
Professor Horton continued, "To fully apply this research to improving the productivity of
Source:Biotechnology and Biological Sciences Research Council