Apical meristem differentiation in reproductive and vegetative shoots in rhizomatous Leymus chinensis

Abstract

To explore the difference in apical meristem (SAM) differentiation between reproductive shoots and vegetative shoots, as well as the effects of low winter temperature on spiking of Leymus chinensis (L. chinensis) using paraffin-embedded slices, we compared the changes in SAM differentiation of grasses after regreening but before spiking date, of vegetative shoots after spiking, and of grass that grew continuously in a greenhouse throughout winter. For the grass after regreening but before spiking data, SAM differentiation was observed in the early stage, elongation stage, single ridge stage, double ridge stage and subsequent stages simultaneously. For the vegetative shoots that were measured after spiking, SAM differentiation was observed only in the early stage, elongation stage and single ridge stage but not in the double ridge stage or subsequent stages. For grass that grew in a greenhouse through the winter, new leaves developed continuously, increased in stem length and had no spiking, and SAM differentiation was observed only in the early stage, elongation stage and single ridge stage. Only grass experiencing SAM differentiation in the double ridge stage can head. The study also determined that low winter temperature played an extremely important role in the spiking of L. chinensis. Key words: Leymus chinensis, reproductive shoots and vegetative shoots, shoot apical meristem differentiation, spike formation, low winter temperature.