Effects of light environments on the phenotypic plasticity of three shrubs in southern China grassland
Phenotypic plasticity is a crucial pathway for plants to adapt to the heterogeneous environments.It is essential to investigate the adjustments of plant morphological traits and biomass allocation patterns,which contributes to understanding the adaptation of plants to different environmental gradients.In order to illustrate their adjustments of morphological traits and biomass allocation patterns to the two comparative environments of high light (outside of the forest) and low light (inside of the forest),we studied three typical shrubs (Salix etosia,Rubus setchuenensis,and Hydrangea aspera) at the Qishan pasture in Chongqing Municipality,southwest of China.The results indicated that the plant height,crown width,crown length,and crown area of H.aspera increased significantly under low light,while S.etosia and R.setchuenensis showed no significant difference between the two light environments.For R.setchuenensis and H.aspera,individual leaf area and specific leaf area were significantly higher in low light than in high light,while S.etosia showed no significant change.Furthermore,H.aspera had greater new branch biomass allocation and aging branch biomass allocation under low light,while S.etosia and R.setchuenensis did not.In addition,root biomass allocation ofR.setchuenensis was significantly higher under low light,while neither of S.etosia and H.aspera showed significant difference between the two light environments.Higher logarithm of root to shoot ratio (R/S) ofH.aspera was observed under low light,but not for S.etosia or R.setchuenensis.Finally,morphological plasticity indexes were higher in R.setchuenensis and H.aspera than in S.etosia but biomass allocation plasticity index showed no significant difference among the three shrubs.The results demonstrated that the adjustment of the morphological traits and biomass allocation patterns for the three shrubs is species-specific under different light environments.
southern China grasslandSalix etosiaRubus setchuenensisHydrangea asperalight environmentmorphological traitsbiomass allocationphenotypic plasticity