Root Anatomy of Clonal Species from Czech Republic: Diversity of Root Buds

The production of belowground bud-bank by development of shoot from roots (root-sprouting) is an example of the successful strategy that plants from disturbed areas employ after injury. In Czech Republic about 10 % of vascular plants are capable of producing buds on roots. The formation of buds may be induced by partial or total damage of aerial organs (regenerative buds), or may be spontaneous (spontaneous buds), related to plant life cycle. In woody plants, regenerative buds are exogenous and do not have traces connected to the root center whereas spontaneous buds have these traces and their growth follows secondary thickening. Two different origins of root buds were also described for herbaceous species (exogenous and endogenous), however the old anatomical data available have not been well documented and cannot be used for comparative studies. In order to understand the diversity of anatomical traits behind the success of vegetative multiplication of root-sprouters we examined the root-bud anatomy of 50 species from Czech flora (Table 1) with different sprouting capabilities. The roots were collected during the plant flowering from different communities; root fragments were excised and cultivated in climate chamber to induce bud formation. The samples were fixed and stored in ethanol 70%; standard anatomical procedures were applied for confection of permanent slides. The analysis showed that buds have different sizes, may be formed along root fragments or also emerged from callus. In all cases, without respect to spontaneity of bud formation, buds displayed vascular traces connected to root center and their growth often followed secondary thickenning, which imply that in herbs even regenerative root buds are preformed in roots and are capable immediately grow into new sprouts. In next studies we will focus on early ontogeny of root buds to be able to distinguish a tissue of their origin.