>I have found gemmae (sidebuds) for P. villosa who is self pollinating =20
>while for P. alpina, who is cross pollinated, I haven't found any gemmea.
>However, P. villosa seems to be a weird species. I haven't sofar found=20
>any seedlings for it and seedproduction and survival is low. How does it=20
>make it?
I introduced my statement concerning vegetative/generative propagation with
'as a general rule', meaning there are exeptions. One exeption is - I
agree with you - P. alpina which is not self pollinating but does not form
gemmae. P. alpina is a special case as it is the only winter bud forming
species with perennial roots. In all other species the roots decay in
winter and the hibernaculum forms new roots in spring. P. alpina forms no
gemmae in the classical sense but sometimes the central root trunk produces
one or more sideplants (which are in fact very short stolons) resulting in
one plant with several vegetative axes. This is in particular the case in
plants infected by the microfungus _Ustilago pinguiculae_ . These plants
are very vigorous, have an overaverage size and an overaverage number of
flowers as they obviously profit from the infection (infected specimens are
easiliy identified by their violet-brownish pollen).
I didn't notice gemmae in P. villosa up to now but you certainly saw much
more specimens than I. P. villosa makes rather large seed capsules (in
comparison to the very small plant size) with relatively large, highly
fertile seeds. This was also observed and described by Casper (Ping.
monography). As only those seedlings will survive which fall into a
suitable place in the uppermost Sphagnum layer - not totally on the surface
(to dry) but not to deep (to dark) - survival may in fact be low. But
anyhow this old species made it for already a few million years.
KInd regards Juerg
___________________________________________________
Juerg Steiger, Institut fuer Aus-, Weiter- und Fortbildung IAWF
University of Bern, Inselspital 37a, CH-3010 Bern, Switzerland
Office: ++41 31 632 98 87, Fax: ++41 31 632 98 71