关键词: 进化生物学, 基因组学, 入侵植物, 入侵性, 模式物种

Abstract

Invasive alien species threaten both native ecosystems and local economies and thus, considerable efforts have been expended to understand why certain alien species invade their non-native ecosystems so successfully and what consequences their successful invasions have for the invaded ecosystems. However, the mechanisms underlying the successful invasions by alien plants remain highly controversial as little is known about the determinants of plant invasiveness; this information is critical in understanding the mechanisms of successful invasions. With the development of new techniques, a new area, ‘invasive plant genomics’, emerged recently, in which genomic approaches are used for understanding plant invasiveness, and hence plant invasions at the genetic level. Here we review three genomic approaches that could be used in plant invasion biology, and discuss the selection of model invasive species and future research directions in invasive plant genomics. First, comparative genomics offers a way to analyze genome constitution and structure based on genome mapping and full sequencing. Second, functional genomics allows us to identify candidate genes that contribute to the invasive characteristics through natural selection experiments, and determine their functions using “forward ecology” methods. Third, epigenetic genomics complements to the above two approaches, and provides information on gene expression patterns, thereby helping us to understand interactions between genes and the environment. With these genomic approaches, it is possible to dissect the invasiveness-related genes and their expression and regulation patterns, identify invasive genotypes and hence understand plant invasiveness. With this information it is theoretically possible to disassemble plant invasion mechanisms and define the evolutionary patterns during plant invasions. Through use of genomic tools, much progress has already been made in two aspects of plant invasions, namely the molecular basis of weed herbicide-resistance and rhizome development in invasive plants. However, invasive plant genomics is still at an early stage. We urgently need to identify ideal model invasive plants or model systems for use in invasive plant genomics. Other important issues that need to be addressed in future research include genomic information accumulation, molecular responses to varying environmental conditions and systems biology of invasive plants.

Key words: evolutionary biology, genomics, invasive plants, invasiveness, model species