Prelimimary Research On The Role Of Auxin In Physcomitrella Leaflet Explants Regeneration Process

Plant regeneration is an important part of plant physiology research, and is the physiological basis of plants genetically modified and fast reproduction. All parts of Physcomitrella can regenerate into new whole plants without any additional phytohormones. The Physcomitrella leaf has only one cell layer. That means, the effect of external phytohormones to every cell is equal. Therefore the leave explants of Physcomitrella are quite suitable for regeneration researches.In this study, a stable system of Physcomitrella leaves excising, cultivating and continuous observation were established. And the auxin signal was observed in regeneration process of Physcomitrella leave explants. The GUS staining results showed that the endogenous auxin content was increased and distributed in a polar pattern which was major in midrib and leaflet base. Exogenous auxin application could accelerate the speed of leaflet explants regenerate out new protonema. Exogenous NPA has no obvious influence on the regeneration process of Physcomitrella leaflet explants. The regeneration position may be determined by the location of the wound. The results above suggest that there is polar auxin transportation mechanism which could be suppressed by KOH in Physcomitrella.