Abstract: Biological invasion is the second major driver for biodiversity loss. Understanding the invasion mechanism can improve our ability to control invasive species. Phenotypic plasticity, which has a genetic basis, is considered as one of the most important mechanisms for the successful invasion of alien plants. In the past 30 years, the research on phenotypic plasticity has been surging. To explore the phenotypic plasticity mechanism of successful invasion of alien plants, the combinations of field investigations and transplantation experiments, crossdisciplinary research of macroecology and molecular ecology have been used. We reviewed the phenotypic plasticity of alien plant invasion from the concept, the research and development of phenotypic plasticity and its ecological significance in plant invasion. Perspectives in future researches of phenotypic plasticity of invasive plants were also proposed. The ecological role of phenotypic plasticity is a hotspot in current research. Phenotypic plasticity, along with genetic differentiation, is an important strategy for alien species to adapt to new environment, which enhances adaptability and intrusion capability. In the future, comprehensive multidisciplinary research is the trend for studies on phenotypic plasticity. The research of the invasion mechanism of alien plants is expected to combine environmental factors, such as climate change and land use, with phenotypic plasticity, applications of the methods of genomics and molecular biology, and quantitative analysis and comparison of phenotypic plasticity across individuals, populations, and species.

Key words: phenotypic plasticity, biological invasion, adaptability, invasive ability.