Root exudate is allelopathic in invaded community but not in native community: Field evidence for the novel weapons hypothesis

Abstract

Invasion by exotic species threatens natural ecosystems (Wilcove et al. 1998) and has severe economic ramifications (Pimentel et al. 2000). In many cases, exotic species that form near monocultures in their invaded range are much rarer in their native communities (Lonsdale & Segura 1987; Braithwaite et al. 1989; Malecki et al. 1993; Eckert et al. 1996; Meyer & Florence 1996; Bruce et al. 1997; Paynter et al. 1998; Memmott et al. 2000). Interactions of invasive plants with above-ground enemies (Wolfe 2002; Mitchell & Power 2003), the soil ecosystem (Beckstead & Parker 2003; Reinhart et al. 2003; Callaway et al. 2004; Thorpe et al. 2006; Callaway et al. 2008), and other plant species (Callaway & Aschehoug 2000; Prati & Bosdorf 2004; Vivanco et al. 2004; Callaway et al. 2005a) appear to be altered in a manner that favours the growth of the invasive plant in invaded communities. However, experimental studies of invasive species in situ in both the native and invaded ranges have rarely been performed (Maron et al. 2004; Hierro et al. 2006).

Citation

Thorpe, Andrea S.; Thelen, Giles C.; Diaconu, Alecu; Callaway, Ragan M. 2009. Root exudate is allelopathic in invaded community but not in native community: Field evidence for the novel weapons hypothesis. Journal of Ecology. 97: 641-645.