Sunday, July 25, 2010

When Flowers Bloom

Crab Spider Salad- Click to enlarge
Ever wonder how flowers decide it is time to flower?  Me neither, but now that I mention it, that is an interesting question.  Blossom time is critical in both pollination and the timing of seeds which are distributed by wind, insects or other animals.  Further on the food chain, butterfly emergence is important in flower's pollination and predators may be awaiting that time as well, as seen with the crab spider picture from MDC.
It turns out that the flowering season of plants is a response to the length of the day, a process known as photoperiodismTry dropping that one in your next conversation.  And how do they remember when it is best for them to flower?  Part of the answer lies in their genes.
A study of a flowering mutant of Arabidopsis, which had an altered response to photoperiod, was used in a study led by Dr Stephen Jackson, as reported in Science Daily.  He and coworkers discovered a mutant gene which altered the blooming time.  "They then cloned a working version of the gene, known as DAY NEUTRAL FLOWERING (DNF), from a normal Arabidopsis plant and introduced it into the mutant plant to restore its normal flowering response to day length."
Scientists can override complex pathways that control flowering by artificially inducing or inhibiting key flowering genes such as DNF and CONSTANS. This can already be done in the laboratory by spraying an 'inducing agent' onto plants, stimulating them to flower early.
This could be used to extend the length of the harvesting season or to co-ordinate flowering or fruit production to a specific time. Growers already regulate the flowering of a few plants such as Chrysanthemum and Poinsettia, the latter specifically for Christmas and Easter.
Imagine the confusion if Spring Cress started blooming in the fall or Deciduous Holly berries appeared in the spring.  I am always concerned when we mess with Mother Nature, but I might forgive scientists if they could get Sericea Lespedeza to forget about blooming.