Effects of size and vertical distribution of buds on sprouting and plant growth of the clonal emergent macrophyte Miscanthus sacchariflorus (Poaceae)

Abstract

Sprouting from bud bank is important in plant regeneration to maintain population dynamics in clonal plants. The plant regeneration may be directly determined by the bud properties since buds are the primary shoot-producing meristematic organs. The aim of this study was to investigate sprouting and plant growth as affected by bud sizes (large and small) and vertical distribution in soil layer (0–10cm and 10–20cm) of the clonal emergent macrophyte Miscanthus sacchariflorus through a sprouting experiment. Sprouting ratio (i.e. the ratio of sprouted buds to total buds) was highest in large buds from the 0 to 10cm soil layer (80%), intermediate in small buds from the 0 to 10cm layer (70%) and in large buds from the 10 to 20cm layer (60%), and lowest in small buds from the 10 to 20cm layer (33.7%). Both plant height and accumulated biomass correlated with bud size, except for a higher accumulated biomass in small buds from 0 to 10cm soil layer than those between 10 and 20cm. The content of soluble sugar was highest in the large buds from the 0 to 10cm soil layer (594.23μgg−1), and lowest in the small buds from the 10 to 20cm layer (433.9μgg−1). Starch content was not affected by either bud size or soil layer. These data indicate that both bud size and distribution soil layer have significant effects on sprouting capacity and plant growth, which might be closely related to soluble sugar content in buds.