Effective and easy way of establishing in vitro culture of mosses, Bryum argenteum Hedw. and Bryum capillare Hedw. -Bryaceae

Abstract

There is today a general unawareness of the fact that the technique of culturing plant tissues and organs under axenic conditions was first established and profitably employed in bryophytes, especially mosses (S e r vet t a z 1913). However, despite such a promising start, bryophytes did not retain for long their rightful place as highly favored research objects, so that most studies of plant morphogenesis are now being done on vascular plants. Apart from the favorable economic aspect, of experimenting on bryophytes, many fundamental and applicative physiological, genetic, morphogenetic, evolutionary and other problems can be tackled more easily by using bryophytes than vascular plants. Bryophytes are the second largest group of higher plants after flowering plants [Magnoliopsiday; with approximately 28.000 species found worldwide. However, most bryophyte species have no commercial value, and are therefore less attractive in a wide range of studies. Some 40% of these tiny species are endangered at present and in urgent need of active protection and conservation. Despite a long history of growing bryophytes in culture and the existing of different-sized collections maintained by some investigators, any newcomer wishing to start their cultures faces a stiff challenge (S a r g e n t 1988). One of the latest ideas is to establish sterile in vitro cultures, then micropropagate plants and later consider methods of their reintroduction into potential native habitats. The first relevant steps in Yugoslavia have already been made and are presented in this communication. Bryum argenteum Hedw. and Bryum capillare Hedw. (Bryaceae) were chosen for this experiment as they are unendangered cosmopolitan species and a model system for further in vitro investigation of mosses. These species are easily accessible because their habitats include urban and suburban areas. Bryum argenteum Hedw. is quite frequent while Bryum capillare Hedw is sporadic. The plants grow up to 5 mm in height and in the form of very small cushions. Reproduction of these species is mostly vegetative, although both are known to produce gametangias. In Bryum capillare Hedw., sporphytes are not usually seen, while in Bryum argenteum Hedw. they are quite rare (S