Abstract:

Resource sharing among connected ramets (i.e. clonal integration) is one of the distinct traits of clonal plants. Clonal integration confers Moso bamboo (Phyllostachys pubescens) a strong adaptability to different environmental conditions. But the mechanisms of how clonal integration makes Moso bamboo has better performance are still poorly understood. In this study, acropetal and basipetal translocation of photosynthates between Moso bamboo ramets were analyzed separately to investigate how clonal fragments obtain higher benefits under heterogeneous N conditions. Clonal fragments of Moso bamboo consisting of two interconnected mother–daughter ramets were used, each of the ramets was subjected to either with or without N addition. The acropetal and basipetal translocation of ¹³C-photosynthates was separated via single-ramet ¹³CO₂-labeling. Mother ramets translocated more ¹³C-photosynthates to daughter ramets with N addition, and the translocation of ¹³C-photosynthates to mother ramets was more pronounced when daughter ramets were treated with N addition. The ¹³C-photosynthates that were translocated from mother ramets without and with N addition were mainly invested in the leaves and roots of daughter ramets with N addition, from daughter ramets with N addition were mainly invested in the leaves and roots of mother ramets with and without N addition, respectively. These results suggest that mother ramets preferentially invest more resources in nutrient-rich daughter ramets, and that daughter ramets serve as efficient resource acquisition sites to specialize in acquiring abundant resources based on the resource conditions of mother ramets. Clonal plants can improve their resource acquisition efficiency and maximize the overall performance in this way.

Key words: carbon allocation, habitat heterogeneity, ¹³C-CO₂ labeling, resource integration, Moso bamboo