Effects of nitrogen addition on clonal integration between mother and daughter ramets of Moso bamboo: a 13C-CO2 pulse labeling study

Abstract

Abstract Aims 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. Methods 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 were separated via single-ramet 13CO2-labeling. Important Findings 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 through this way.