Some very interesting work has been done to identify how smoke promotes germination. A compound called Karrikinolide that is present in smoke is believed to be the primary factor that breaks seed dormancy. It appears to act similarly to gibberellin or works synergistically with giberellin. It can have an effect at very low concentrations, so not much needs to reach the seed to have an effect. Karrikinolide has been found soil after fire, so it may not be necessary for direct contact between smoke and the seed to have an effect. > I think the actual material which breaks down germination inhibitors is, in > the majority of cases, charate. Smoke probably doesn’t come into contact > with seeds long enough for anything to happen. -- William A. Hoffmann Associate Professor Department of Plant Biology North Carolina State University Raleigh, NC, 27695-7612 Phone: (919) 513-7668 http://www4.ncsu.edu/~wahoffma/labhome/… _______________________________________________ pbs mailing list pbs@lists.ibiblio.org http://pacificbulbsociety.org/list.php http://pacificbulbsociety.org/pbswiki/