[Module structure and growth pattern of Stipa baicalansis clone in Songnen Plain of China]

By the method of digging up whole tiller tuft, this paper quantitatively analyzed the module structure and growth pattern of Stipa baicalansis clone under the cultural conditions in the Songnen Plain of Northeast China. The results showed that after two growth seasons of vegetative reproduction, the tuft size of the clone in its growth stopping period at the end of September was 9.4 +/- 3.24 cm, and the total number of the clonal modules was 161.5 +/- 85.2, among which, the individuals of reproductive and vegetative tillers were 14.6 +/- 11.48 and 146.9 +/- 78.70, occupying 9.25% and 90.75% of the total, respectively. The total biomass of the clonal modules was 53.8 +/- 34.22 g, and the biomass of reproductive and vegetative tillers was 25.0 +/- 20.34 g and 28.8 +/- 19.43 g, occupying 43.75% and 56.25% of the total, respectively. With the increase of tuft size, the number of different modules was in a linear isogony growth, while their biomass was in an power allometry growth. There was a significant (P < 0.05) or very significant (P < 0.01) power positive correlation between the biomass of different modules and the number and total biomass of clonal modules. The mean productivity of unit reproductive tiller was about ten times higher than that of unit vegetative tiller, and the phenotype plasticity of the number and biomass of reproductive tiller was larger than that of vegetative tiller.