Abstract: Leaf construction cost (CC) is an important indicator in measuring the energy demand for plant leaf construction, and reflects the energy utilization strategy of plant leaf. Lower leaf CC has been hypothesized to give invasive plants a growth advantage through efficient energy utilization. In this paper, the invasive plant Flaveria bidentis and its cooccuring native plants Xanthium sibiricum, Amaranthus retroflexus, Setaira viridis, Chenopodium glaucum, and Vigna radiata were selected as the objects to compare their differences in leaf CC and related characteristics. The construction cost per unit leaf mass (CC_mass) of F. bidentis was significantly lower than that of the five cooccuring native plants, being 76.6% of the average CC_mass of the native plants. Likewise, the construction cost per unit leaf area (CC_area) of F. bidentis was significantly lower than that of the native plants except S. viridis, being 74.4% of the average CC_area of the native plants. The leaf carbon and nitrogen concentrations of F. bidentis were significantly lower than those of the cooccuring plants. The leaf ash content of F. bidentis was significantly higher than that of X. sibiricum, A. retroflexus, S. viridis, and V. radiate, but had less difference with that of C. glaucum; while the leaf ashfree calorific value of F. bidentis was significantly lower than that of the native plants except C. glaucum. For all test plants, their leaf CC_mass was significantly positively correlated with their leaf carbon concentration and leaf ashfree calorific value, but negatively correlated with the leaf ash content. As compared with that of the cooccuring plants, the lower leaf CC of F. bidentis could be one of the reasons causing the successful invasion of this invasive plant.

Key words: biochar, accumulation,  seed quality., tree peony, nitrogen, translocation