ABSTRACT
Figure 3.1 (See color insert.) Pictorial representation of the novel weapon hypothesis: In the native range, chemicals released by the plants exhibit positive interactions toward neighboring plants, herbivores, and microbes possibly due to tolerance acquired over the years. In the invaded range, on the other hand, chemicals released by the exotic plants serve as novel weapons to the other naive neighboring plants, herbivores (generalists), and microbes that were not earlier exposed to such chemicals. Thus, there is no evolved tolerance in them toward novel chemicals; this results in negative interactions that provide selective advantage to the exotic plant (donor of novel chemicals).
