Phenotypic Plasticity And Spatial Expansion Strategy Of Potentilla Anserine Clonal Population In Heterogeneity Habitat

This research is designed to deal with soil nutrients("nutrient experiment" for short) and light intensity("light experiment" for short) of field experiment,we set three levels of the same factor in a experiment area,i.e.,different combinations of three heterogenous habitat which is high - medium - low,medium - high - low and high - low - medium,in this way,we can simulate habitat heterogeneity of natural grassland.We studied the plasticity of plant height,leaf length,leaf width,stolon length,spacer length of Potentilla anserine Focke in response to differing levels of light intensity and soil nutrient gradient;compared colonization rate of ramets and numbers of stolons,ramets in heterogenous habitats;discussed spatial expansion strategy of clonal plant populations.In nutrient experiment,plant height of 2007,2008 and leaf length of 2008 were significantly higher in high-nutrient patches and medium -nutrient patches than low-nutrient patches(p＜0.05).Leaf length in medium -nutrient patches was significantly higher than low-nutrient patches(p＜0.05) in 2007,there was no significant difference in the three types of leaf width in 2007,Leaf width in high-nutrient patches and medium -nutrient patches was significantly higher than low-nutrient patches(p＜0.05) in 2008,primary spacer length in medium -nutrient patches was significantly higher than high-nutrient patches and low-nutrient patches in 2007.Stolon length,internode length,secondary spacer length had no significant difference in three heterogenous habitats in 2007.In light experiment,plant height and leaf length in low- light patches was significantly higher than high- light patches and medium - light patches(p＜0.05) in 2007,plant height in medium - light patches and low - light patches was significantly higher than high- light patches in 2008(p＜0.05),with the light intensity decreased, leaf length increased significantly in 2008(p＜0.05).Leaf width had no significant difference in the three heterogenous habitats in 2007.With the light intensity decreased,leaf width increased significantly in 2008(p＜0.05),internode length in medium - light patches was significantly higher than high- light patches in 2007, primary spacer length in low - light patches was significantly higher than high- light patches in 2007,secondary spacer length in low - light patches and medium - light patches was significantly higher than high- light patches(p＜0.05) in 2007,stolon length had no significant difference in the three heterogenous habitats in 2007.In nutrient and light experiment,numbers of stolons and ramets showed no significant difference in both sides of parent-ramet patches,colonization rate of both sides of parent-ramet patches showed significant difference only in the high-low - medium patch in light experiment of 2008.The main conclusions are as follows:The main phenotypic characteristics of Potentilla anserine clonal population showed plasticity in response to different levels of light intensity and nutrient availability.It is an adaptive strategy for Potentilla anserine population in heterogenous habitat.There is no obvious orientation of stolon extension and ramet placement,which parent ramet placed in different levels of light intensity and nutrient availability.It's considered that,direction of spatial extension of Potentilla anserine Focke population is random.