Bais Harsh P, Vepachedu Ramarao, Gilroy Simon, Callaway Ragan M, Vivanco Jorge M
Department of Horticulture and Landscape Architecture, Cell and Molecular Biology Program, and Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO 80523, USA.
Science. 2003 Sep 5;301(5638):1377-80. doi: 10.1126/science.1083245.
Here we present evidence that Centaurea maculosa (spotted knapweed), an invasive species in the western United States, displaces native plant species by exuding the phytotoxin (-)-catechin from its roots. Our results show inhibition of native species' growth and germination in field soils at natural concentrations of (-)-catechin. In susceptible species such as Arabidopsis thaliana, the allelochemical triggers a wave of reactive oxygen species (ROS) initiated at the root meristem, which leads to a Ca2+ signaling cascade triggering genome-wide changes in gene expression and, ultimately, death of the root system. Our results support a "novel weapons hypothesis" for invasive success.
在此，我们提供证据表明，美国西部的入侵物种斑点矢车菊（Centaurea maculosa）通过从根部分泌植物毒素（-）-儿茶素取代本土植物物种。我们的结果表明，在（-）-儿茶素的自然浓度下，田间土壤中本土物种的生长和发芽受到抑制。在拟南芥等敏感物种中，这种化感物质会在根分生组织引发一波活性氧（ROS），进而导致Ca2+信号级联反应，触发全基因组范围的基因表达变化，最终导致根系死亡。我们的结果支持入侵成功的“新武器假说”。
